Dairy Plant Design And Layout PDF

DAIRY PLANT DESIGN AND LAYOUT Sunil M. Patel A.G. Bhadania  Dairy Plant Design & Layout Course Developers Sunil M. Patel & A.G. Bhadania Department of Dairy Engineering AAU, Anand...

DAIRY PLANT DESIGN AND LAYOUT Sunil M. Patel A.G. Bhadania  Dairy Plant Design & Layout Course Developers Sunil M. Patel & A.G. Bhadania Department of Dairy Engineering AAU, Anand Editor Dairy Plant Design and Layout www.AgriMoon.Com 2  Course Outline 3 (2+0+2) Module 1. Introduction of Dairy Plant Design and Layout Lesson 1.Types of Dairies and Perishable nature of milk Lesson 2.Importance of Dairy Plant Design Lesson 3.Milk Procurement Lesson 4.Milk Reception Lesson 5.Classification of Dairy Plants Module 2. Location and Site Selection for Dairy Plants Lesson6. Location of Dairy Plant and Types of Locations Lesson 7.Location of Fluid Milk Plant and Milk Product Plant Lesson 8.Site Selection Lesson 9. Location of Milk Product Plant Module 3. Planning and principles of dairy plant layout Lesson 10.Importance of planning and principles of dairy plant design Lesson 11. Dairy building planning Lesson 12.Preparation of process schedule Lesson 13.Space requirement for dairy plant Lesson 14.Estimation of service requirements including peak load consideration Module 4. Design aspects of dairy plant Lesson 15.General points of consideration for designing dairy plant Lesson 16.Different types of layouts Lesson 17. Single or multilevel design Lesson 18.Service accommodation Lesson 19. Arrangement of different sections Lesson 20. Service pipe- line layout Lesson 21.Equipment layout Dairy Plant Design and Layout www.AgriMoon.Com 3 Lesson 22.Layout of offices and workshops Lesson 23. Material handling Lesson 24.Preparation of detail layout with model planning Lesson 25.Common Problems Module 5. Building construction materials and type of building construction Lesson 26.Choice of building construction materials - Brick, sand, cement, lime etc. Lesson 27.Building materials – stones, wood, metal, glass etc. Lesson 28. General requirement of dairy floors and floors for different sections Lesson29.Structural Aspects of Foundations, Roofs, Ceilings, Walls, Doors and windows Lesson 30.Drain and drain layout for small and large dairies Lesson 31.Ventilation, Illumination and fly control Lesson 32.Paints, coatings and mold prevention Dairy Plant Design and Layout www.AgriMoon.Com 4  Module 1. Introduction of Dairy Plant Design and Layou t Lesson 1. Types of Dairies and Peris hable nature of milk 1.1 Introduction Since India is the leading country in milk production in the world at a fast rate, it has been lead to a need of very scientific layout and planning for the dairies being set up by the dairy designers, engineers and architects. In some organized sectors, milk collection and chilling of milk is done, before it is transported for processing at dairy factory. The dairy technology commences with processing of milk at dairy plant for market milk and various dairy products. The dairy plant layout and design means designing a layout plan for dairy plant. i.e layout of various sections in dairy building, equipment layout, laying of dairy machines in each section for economical and efficient movement of men and material in the plant. Milk and milk products, however, impose certain requirements which do not occur elsewhere in food or other industries. These special requirements affect the structure and the layout of the building, the provision and distribution of services and the choice of site. The products of dairy industry – milk for liquid consumption, yoghurt, curd, cream, butter, ghee and similar products, cheese, milk powder and so on- are foods which play a fundamental part in human nutrition. Materials and methods used in building must be such as to give the longest practical life with the minimum of maintenance, in spite of working conditions which are often relatively severe from both the mechanical and chemical point of view. It should also be seen that most of the repairs, alterations or extensions could be done without stopping the production. These characteristics demand closest attention during planning. There is a need for highest standard of hygiene. Milk is most suitable medium for the growth of microorganism, therefore every possible measure should be taken to reduce the possibility of contamination, especially after processing. A good layout design and use of proper materials and techniques make great contribution towards hygiene. The dairy layout needs careful thought and planning keeping in view manufacture of the products and their commercial aspects. 1.3 Peris hable nature of milk Milk by its nature is perishable. The following three factors contribute to its being perishable: (i) Contamination with bacteria due to widely dispersed and unhygienic collection methods (ii) Warm temperatures of tropical climate (iii) Prolonged time before cooling or processing In practice, none of these factors can be eliminated completely, so if any one is accentuated, the life of milk will decrease. Therefore, every effort must be made to minimise these factors on the farm, during collection at milk plant and during distribution to consumers. At the farm, the aim must be to cool milk as soon as possible after milking. Ideally, the milk should be chilled to 4˚C within two hours after milking. If for any reason this can not be done at farm, quick transport of milk to the plant is essential. If milk can be stored conveniently at the farm or local collecting depot at low temperature, the organization of transport to milk processing plant is simplified to greater extent by transporting bulk quantity in insulated tankers. The type, size and number of vehicles Dairy Plant Design and Layout www.AgriMoon.Com 5 necessary are, therefore determined not only by the usual factors such as distance or nature of roads but also by the condition of milk production. When the milk is drawn from the udder of the milch animals (cows, buffaloes, goat, sheep, etc.), the quality of milk is almost sterile. The milk has its own anti- microbial system present which is active till 2 to 3 hours of milking. The components in milk such as lacto-peroxidase system, immunoglobulins, lactoferrin, etc. have the anti- microbial effect. The perishable nature of milk comes into picture with the contamination from air, huma n, and milking utensils. The temperature of milk during milking is equal to body temperature i.e., 37°C. The milk being very rich in nutrients such as carbohydrates, fats, proteins, minerals, vitamins and water, becomes good media for the growth of micro-organisms. So the milk should be immediately sent to the dairies within 2 or 3 hours of milking, before it gets sour. If the dairy is very far away from the milk collection area, it should be chilled to below 10°C in the bulk milk coolers at the farm level (village co-operatives and/or chilling centres) so that the microbial activity is inactivated. 1.2 Types of Dairies: ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 6  Lesson 2. Importance of Dairy Plant Design 2.1 Introduction: Dairy Plant design, involves the estimation of capacity, process scheduling and proper layout so as to achieve the objective of handling milk at the least cost and greatest safety. However, the dairy industry and the plant design has to meet certain special requirements and need to be focused on these. The following are the few aspects that make the dairy industry as a unique one. Special Characteristics of Dairy Industry: 1. Perishable nature of milk: Milk is one of the most perishable of the agricultural commodities, and has only few hours of shelf life unless it is chilled and processed. Hence, the TIME factor is the most important aspect to be involved in the dairy plant design and la y out 2. Milk is an essential commodity. It provides nutrition especially to children and aged. Hence the dairy industry has a high profile in the society, and its functioning is very essential to the well being of the society. 3. Seasonal nature: The dairy industry has to deal with availability of raw milk fluctuations depending on the season. It is available in certain months, called Flush season when most of the calving and green fodder is available. During summer months, when milk availability dips due to most of the animals coming to end of their lactation period. Hence, OVER CAPACITY is the factor to be considered in plant design and layout, as the plant is to meet the peak procurement of the flush season, while in the remaining months it is having excess capacity. Also flexibility of the plant design and layout has to be considered. 4. Milk is a food item, which has to be consumed, especially by children and old people. Hence, PLANT HYGIENE is the important factor in plant layout and design. 5. Effluent disposal of dairy plant is essential as the volume and BOD value of the dairy effluent is high. Sufficient planning is required to handle this high volume of effluent to be handled by Effluent Treatment Plant (ETP). 6. Dairy Industry has to meet the various legal aspec ts and mandatory requirements. It has to meet the Industrial act, Labor act, Boiler act, Pollution control act. It also has to meet the HACCP and FSSAI guidelines. 2.2 Importance and economics of plant design: The products of dairy industry i.e., liquid milk, yoghurt, curds/dahi, cream, butter, ghee, ice-creams, cheese, milk powders, shrikhand, traditional Indian dairy products etc. are foods which are very important for human nutrition. Therefore, it is very necessary that the milk and milk products should be available to everyone at the lowest possible rate. Also the profit margin that the dairy entrepreneur expects is limited. Therefore, the capital outlay of the building and plant should be economical. Planning must be done wisely to make best use of the labor employed and to keep operating costs to a minimum. Materials and method used in building must be such as to give the longest practical life with the minimum maintenance, in spite of working conditions which are often relatively severe from both mechanical and chemical points of view. It should also be without stopping the production. Dairy Plant Design and Layout www.AgriMoon.Com 7 To extend the shelf- life some techniques like quick heating, quick cooling, acidification etc. are applied and also various advanced packaging techniques are used. The Dairy Technology starts with milk processing till the final products such as market milk and conversion into various products. So the subject Dairy Plant Design and Layout is the designing of layout plan for a dairy plant, i.e., layout for different sections in the dairy building, equipment layout, laying of dairy machines in such a manner that it allows efficient and economical movement of men and material in the plant in each section. The subject contains several applications of fundamental topics, such as locations site selection, building materials, specific requirements of each section including service sections. 2.3 Legal and comme rcial aspects of plant design: Care should be taken to provide adequate natural and artificial lighting. Every possible effort should be made to ensure that the building and the site will be pleasant to look at. The architect can provide a good landscape and an attractive outlook. The welfare of the employees must be kept in view. Canteen facilities are essential to meet the requirement of Labor act. Ultimately, the dairy plant layout requires careful thought and planning keeping in view manufacture of the products and their commercial aspects. A sound layout engineering contains allowance for increase in capacity by arranging the production departments and selecting the type of building that can be expanded at low cost. It should be easy to increase the output capacity which may be required in the future. A floor arrangement that contributes to the low cost production planning a nd control are achieved in good plant layout. Material control and steady amount of production capacity can be easily attained with minimum idleness of machinery and man. Finally leading to the delivery of products in short notices can be achieved. Safety and good working conditions are very necessary in a proper plant layout. Minimized hazards at the working stations, in material handling, storage, maintenance operations and so on are features of good plant layout. Minimum man hour losses, reduction in cap ital equipment and material losses incorporate improved working conditions. Increased employee moral tends to reduce production costs and helps develop a stable operating force. In planning the building, several important factors have to be studied in deta il before the plant could be developed to the stage of construction. The size of the building and the floor space to be provided depend upon the processes and choice of appropriate steps, numbers and associated equipment to be accommodated and the most important factor of rearrangement of facilities in the initially built building and provision for expansion of the building without costly modifications. A high degree of sanitation is necessary to ensure protection from contamination, odours, chemicals, organisms, etc. This includes the interior and exterior of the building and sanitary conditions of the environment. Simple pleasing design with high utility value without undue importance to architectural factors is necessary. Civil Engineering aspects of plant design : The type and methods of use of civil construction is evolving day by day. New materials are being developed to meet specific requirements of industries. The planning of civil construction is very much related now to meet the requirements of HACCP and FSSAI acts, which are more stringent in nature. Structural modules of RCC Columns and beams gives good flexibility in the location of the equipment and layout of service lines. The height of the ceiling is another important factor. Plain smooth surface of the underside of the ceiling with embedded fixtures for lighting and pipe supports, etc. , into the ceiling is best. Dairy Plant Design and Layout www.AgriMoon.Com 8 2.4 Advantages of a good plant layout 1. A good layout reduces a. the effort in normal material handling of a worker b. cost of handling by direct labor and hence increased productivity per man hour and c. indirect manufacturing cost by decreasing spoilage under difficult handling situation 2. It uses only essential space required and eliminate congestion and accident, permits flexib ility for methods improvement and future expansion besides making supervision easier. 3. It also facilitates scheduling and despatching operation. ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 9  Lesson 3. Milk Procurement 3.1 Introduction: The wide range of milk procurement methods and handling has an affect on the plant design and layout. The method of milk procurement is also changing over the years. The recent trend of Bulk Milk Cooling at village clusters is altogether eliminating the procurement of milk by cans at the Dairy plants. Lack of attention during procurement, processing and storage leads to decrease in the milk shelf- life. Quick chilling of milk should be done during the procurement if the dairy is far away from the Dairy Processing Plant and such milk is to be transported in bulk in insulated tankers to the dairies. In India, milk production is carried out in rural areas from where it is transported to milk processing plant. Thereafter distribution to consumers is done through depots and/or milk parlours. 3.2 Milk procurement: In most of the countries, milk production is carried out in rural areas from where it is transported to milk processing plant. Under Indian conditions, milk has to be regularly collected and transported twice a day, morning and evening. The usual methods of milk collection and reception at dairy plant are: (i) Milk procurement through individual producers: In this milk is brought to the dairy plant by the individual producers in their own vessels of any type. This is possible for those producers who are located nearby milk collection centre. (ii) Milk collected through co-operative organizations: Here, co-operative societies form an organization which is responsible for uninterrupted supply of milk to the dairy plant. Supply of milk can also be affected by single co-operative society formed by milk producers. This is beneficial to the producers as there is no middle man to share profit. (iii) Milk procured through contractors: In this method the contrac tor supplying milk to the dairy plant collects the milk from producers at a cheaper rate and transports the milk to the dairy. Therefore, there is less return to the milk producers, as milk contractor will keep his share in the profit. (iv) Milk reception from milk collection cum chilling centres: This method is generally possible and is prevalent in organized sectors, and dairy operations in India. Milk is collected at various milk collection centres from nearby villages in 40 litre cans usually belonging to the organization. The milk is weighed, tested for fat content and kept ready to be dispatched to the milk chilling centre. From collection centre milk is picked up in an open truck and brought to milk chilling centre or dairy plant, where milk cans are emptied, washed through can washer and sent back to milk collection centres for next day collection of milk. Dairy Plant Design and Layout www.AgriMoon.Com 10 3.3 Three tier structure of ‘Anand Patte rn’ The Anand pattern for collection of milk, processing and marketing of milk and milk product is very popular for co-operative structure in Gujarat, and few other states. Fig. 3.1 shows three tier system of „Anand Pattern‟. i) The Village Society An Anand Pattern village dairy cooperative society (DCS) is formed by milk producers. Any milk producer can become a DCS member by buying a share and committing to sell milk only to the society. Each DCS has a milk collection centre where members supply milk every day. Each member's milk is tested for quality with payments based on the percentage of fat and SNF. At the end of each year, a portion of the DCS profits is used to pay each member a patronage bonus based on the quantity of milk poured. ii) The District Union A District Cooperative Milk Producers' Union is owned by dairy cooperative societies. The Union buys all the societies' milk, then processes and markets fluid milk and products. Most Unions also provide a range of inputs and services to DCSs and their members: feed, veterinary care, artificial insemination to sustain the growth of milk production and the cooperatives' business. Union staff train and provide consulting services to support DCS leaders and staff. iii) The State Federation The cooperative milk producers' unions in a state form a State Federation which is responsible for marketing the fluid milk and products of member unions. Some federations also manufacture feed and support other union activities. The transportation of milk to milk collection centre by various methods has an important bearing on the quality and time constraints placed on the milk procurement. Dairy Plant Design and Layout www.AgriMoon.Com 11  ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 12  Lesson 4. Milk Reception 4.1 Introduction: The objective of handling the milk as quickly as possible continues even at the milk reception, as the milk is still vulnerable to the spoilage, till it is chilled and taken into milk storage tank, and processed. The crucial stage of milk reception also involves the responsibility of checking the quantity, quality for acceptance, and the time management of handling many vehicles. As mentioned earlier the timing is an important parameter while decid ing about the mode of reception and transport. The load, distance to be covered and relative merits are given below in Table 4.1 and 4.2. Dairy Plant Design and Layout www.AgriMoon.Com 13 4.2 Reception at the Dock: The milk as soon as it is received at plant, is weighed, dumped into the dump tank (we igh tank) and has to be chilled before it is stored for processing. This has to be done in quick succession through equipment well planned and installed at milk reception dock and receiving room. The reception of milk at the Raw Milk Reception Dock (RMRD) is done in three ways i.e., in cans, in milk tankers and combination of both. The type, size and number of vehicles can be determined by factors such as distance or nature of the roads and condition of milk production. In the chilling centres or BMCs, the milk is received only in cans (may be 40 lit or 20 lit capacity cans). In case of Marketing Dairies, the milk is received only in milk tankers where as in feeder dairies the milk is received in both cans as well as in tankers. The trend of establishing BMCs at village clusters has changed the mode of reception and monitoring of quality and quantity at Dairies. There are some products that depend on the type of milk like cow and buffalo milk. Therefore, the reception dock may consists of two separate systems for cow milk reception and buffalo milk reception at chilling centres as well as in feeder dairy plants. In most of the dairy plants however, the milk is received as mixed milk. If the milk is received in bulk through tankers, the arrangement has to be made for quick transfer of milk through milk pumps installed at milk reception dock to milk storage tanks. The milk received in the evening may be chilled and the stored for processing next day. All this will need careful planning of layout of equipment at milk reception dock and milk receiving room. Roads leading to milk reception dock and dispatch dock have to be planned in such a manner so as to avoid traffic congestion inside the factory or road blockage. 4.2.1 Essential features of RMRD : The RMRD dock should be of height suitable (usually 1.5 m) to receive milk from whatever mode of transport without spillage during unloading. For Milk tankers, the Tanker Bay must be spacious, suitable for washing and unloading at least two tankers at a time. The pump should be of 20,000 l/h capacity to unload faster. If the milk quantity is to be measured by weigh bridge, it should be properly calibrated and inspected periodically by local weights and measure authorities. If the quantity is to be measured by dip stick alone, then the tanker by must be suitably leveled to avoid errors in measurement. 4.3 The important equipme nts for reception of milk processing plant on the RMRD are: · Can conveyor: It should be of suitable type and length to transport easily the cans from the edge of the dock to the can tilting bar at the dump tank. The rate of reception and capacity of the dairy plant are also important in deciding about the type of can conveyor, like whether a Roller type or motorized chain conveyor. · Milk weighing tank: The equipment involves a weigh bowl and dump tank. The capacity of weigh bowl should be able to weigh at least 4 cans, which may be an average quantity received from each village. Weigh bowl may be linked to indicate on a dial type of scale or through load cells in digital form of indication and recording · Weighing scale: The weigh scale must at least be of 300 kg, so that the normal range of quantity of milk received from village is between 40 to 60% of the scale. The trend of digital indication through load cells are catching up, which has the advantage of recording as well as print out simultaneously, for easy monitoring and documentation. This is improving the confidence level between milk collection centres and dairy that is receiving the milk. · Dump tank with cover: The capacity of Dump tank is at least twice the capacity of weigh bowl, so that while the milk quantity of one village is being weighed, the other quantity is being pumped out from dump tank to the Dairy Plant Design and Layout www.AgriMoon.Com 14 milk chiller. Recent trend is to link the level sensors and milk pump to get started and stopped when the milk level is high and low respectively. · Drip saver: The drip saver must be of SS and should have drain leading to the dump tank, or to a separate can, which is emptied to dump tank from time to time. · Can washer: The capacity of can washer should meet the rate of reception and dumping. Mostly Straight through can washers are chosen, and the empty can conveyor leads the washed cans to the dock or to the edge of RMRD to be loaded into vehicles. · Milk pump: The milk pump used for pumping milk from dump tank to the plate chiller through in- line filter, should match the rate of reception. It is installed at a level lower than the dump tank and has flow control valve at the discharge side, The filter is sometimes located on the suction side to avoid threads, tags, etc connected with cans getting jammed into the pump impeller. The pump, in recent times is linked with control system to operate as per the level in the dump tank, to prevent overflo w of dump tank or pump running dry by oversight of the operator. · Plate chiller: The Plate chiller is usually of PHE type and used for chilling milk to 4 o C. The Plate chiller is sized to meet the reception rate, and may sometimes be two in number, one eac h to receive milk by cans or road tankers. If the chiller is to receive milk from road tankers, the capacity is usually much larger, to meet the higher rate of reception to unload tanker rapidly. · Raw milk silo: This is a vertical storage tank or a battery of storage tanks, that are specifically identified to store raw milk only. The silos can be located outside the processing hall, but connected to the hall through an opening called „Alcove‟. The operation of opening, closing of inlet and outlet valves, measuring the temperature, controlling the agitator etc are done from inside of the processing hall itself, though the silo is located outside. The tank overflow line will be positioned to inside of hall, so that the operator can know if the tank is full and overflowing. · Milk testing laboratory: This is a preliminary testing laboratory, to perform so called Platform tests, like COB, acidity, turbidity, etc. The Reception dock is essentially separated from the processing hall by partition doors, or walls, w ith fly proof devices like air curtains, or mesh doors. The trend now is to provide even the RMRD dock with provisions to prevent entry of flies and insects. The crucial design calculations of the rate of dumping is illustrated by following example : 1. Milk to be received by Dairy Plant: 10,000 LPD 2. Milk to be received by AM and PM in the ratio of: 60:40 3. Milk to be received in the AM: 10,000 x 0.60 = 6,000 lts 4. Milk to be received in two hours 5. Milk reception per hour: 6,000 / 2 = 3000 LPH Hence the design of all the reception dock equipment will be to meet the above requirement of 3,000 LPH. Dairy Plant Design and Layout www.AgriMoon.Com 15  Lesson 5 Classification of Dairy Plants 5.1 Introduction: The design and layout of the dairy plant depend much on the quantity of milk handled and the type of the product made. Some may need refrigerated condition for the distribution of the product, while others may not need such requirement. Some of the products may not need a daily delivery and need to be transported once a week or so. There is a wide variation in the size and type of dairy plants. Fig. 5.1 and Fig 5.2 shows broad classification of milk plants. Dairy Plant Design and Layout www.AgriMoon.Com 16 The milk plants can be classified broadly into two groups – · Liquid Milk Plant This type of plant should be situated/located as close as possible to the consumer area i.e., generally in or on the outskirts of a large city or town. It supplies market milk in chilled condition in small retail packs. · Product Milk Plant Here, there is the production of products like cheese, butter, ice-creams, etc. which do not require daily distribution to the consumers. So the plant should be located near the producing areas. The difference in the location areas of both plants results in the minimized transportation cost. Milk plants can be classified based on its capacity also : · Small Capacity Milk Plants These are usually below 10,000 LPD and may need to load milk in road tankers and send to larger dairies. Very limited local sales of liquid milk could be possible, as these are essentially located in small towns. · Medium Capacity Milk Plants The capacity of the medium sized dairy plant ranges from 20,000 lit to 1,00,000 litres of milk handling per day. Layout for products like market milk, butter & ghee and cheeses can be designed. Each room should be planned separately and arranged with forward flow of product as per requirement. · Large Capacity Milk Plants Here, the plant building may have few floors having multi-product manufacture, where the reception is done at the ground floor and should have both milk treatment and tank storage on the first floor. If products like milk powder are to be manufactured, then the powder plant should placed in different building. The classification in general may be subject to change in the capacities and there can be a certa in overlap in the type and products handled. Some dairies could be handling both liquid milk as well as products, to maximize their market reach and profitability. Though there were certain restrictions in the area of operation of dairies, the same is not strictly enforced or adhered to at present. ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 17  Module 2 - Location and site selection for dairy plants Lesson 6 Location of Dairy Plant and Types of Locations 6.1 Introduction: Location and site selection for dairy plants forms the important first step in plant design and layout. It has a bearing on the profitability of the dairy and initial quality of the milk. The step is further an important one as any mistake here cannot be corrected easily. The size and operation of the plant also gets restricted if the decision is not made properly at this stage. 6.2 Selection of Location: The problem of selecting a location for a dairy plant has been given considerable thought by many authorities. Selecting a location involves large commitments of capital, as a result it must be done with the utmost care. The problem involves selecting a region as well as specific site within that region. The most difficult part of a plant location analysis is determining the criteria by which various location alternatives can be evaluated. As the dairy plant construction involves a very large initial capital investment, numerous considerations must be evaluated at the very beginning in the planning of a new plant. Out of these, the location and site selection requires utmost care as it forms a large single capital investment. It involves selecting a region as well as a specific site within the region, of which the most difficult part is determining the criteria by which various location alternatives can be evaluated. Location is a strategic issue, and the decision where to locate cannot be taken lightly. It is the first decision in the implementation of a project. Upon the decision to proceed, an investment is made which is irreversib le. That investment in bricks and mortar cannot physically be transferred to another location if the decision turns out to be wrong. The most favorable location is one, which attains the lowest unit cost in producing and distributing the product or service to consumers. Traditionally, a location was selected for reasons of economic geography like, 1. Proximity to raw material source 2. Proximity to relatively cheap and abundant energy 3. Availability of relatively inexpensive manpower or specialist skills 4. Proximity or good transport links with materials suppliers and markets. But nowadays, the location decision has become more complex with newer intervening factors like more sophisticated markets, increased competition, short supply of skills, technological change that soon outdate newly installed processes, shooting costs of land and materials, government influences, legal requirements, corporate matters and peoples‟ influences. In general, in selecting an area to locate a plant, following consideration should be given to the following factors Dairy Plant Design and Layout www.AgriMoon.Com 18 1. Availability of spacious land for immediate requirements of all buildings, roads, service facilities, garden, tree plantation for wind break etc., with provision of land for expansion at a future date 2. Accessibility and availability of raw materials 3. Accessibility of market 4. Adequacy & availability of labor 5. Adequacy of transportation facilities 6. Volume of power and fuel 7. Water supply and its quality 8. Soil conditions for heavy loading 9. Site cost 10. Elevation in location to facilitate removal of dairy effluent, suitable treatment and disposal 11. Climatic conditions, including direction of prevailing wind and probable increase in dust and smoke nuisance from the surroundings, and 12. Government laws 13. Market Potential 14. Clean environment The two terms location and site are often confused with each other. It must be clearly understood that, the term „location‟ implies to Area, Region or Territory, while „site‟ is the place, within a selected location, where building is to be constructed. 6.3 Plant location Location is primarily influenced by the nature of the product manufactured. The general location and the specific site should be selected with the aim of attaining as nearly as possible the ideal over-all economic situation for the particular enterprise, may it be a fluid milk plant or milk product dairy. The most favorable location is one that attains the lowest unit cost in producing and distributing the product or service to consumers. 6.3.1 Differences between location and site The two terms location and site are often confused with each other. It must be clearly understood, that, the term „Location‟ implies to Area Region or Territory, while site is the place, where building is to be constructed. Dairy Plant Design and Layout www.AgriMoon.Com 19 6.3.2 Location problem Location problem has to be solved at two levels, first Territory or Region level and second site level. Some location factors may be applicable to both the levels. Still region level and site level are to be given specific consideration. 6.3.3 Types of Location Three types of locations are possible for dairy plants viz. i) city location ii) suburban location and iii) country location. 6.3.3.1 City location: When a city is planned by a town planner, all areas are marked for future buildings. The industries likely to come up are marked in area called „Industrial area‟ and usually dairy plants are allotted a plot in that area only. Dairy plant in the neighborhood of other industry or factories emitting smoke, dust, offensive smell, gases, carries great risk. It is therefore essential, that the location marked for milk plant should be free from all pollution. 6.3.3.2 Suburban location: Suburban location means suburban town or outer skirts of large city. The dairy plant located in this situation has advantages of being close to consumption area with possibility of availing all facilities such as electricity, water, waste disposal and labor etc. 6.3.3.3 Country location: Country location means sitting dairy plant in country or milk producing area. There will be little competition from other industries and land will be cheap. The plant will not create a noise problem and it is unlikely that atmospheric pollution will cause any difficulty. There will be no traffic congestion. Milk supply routes will be short. But it will be away from the city consumption area. For all the dairy plants in whatever region they are, there are some important points which are common and essential to be considered in determining the location. Moreover there are some problem factors applicable to both region level and site level. The former is covered in the subsequent chapters while latter is given in the Table. 6.1. Dairy Plant Design and Layout www.AgriMoon.Com 20 Dairy Plant Design and Layout www.AgriMoon.Com 21  Lesson 7 Location of Fluid Milk Plant and Milk Product Plant 7.1 Introduction: The location of the fluid milk and product plant differ in more ways than one. The fluid milk plant has the requirement of disposing the milk in retail containers or packets, at refrigerated condition to consumer on day to day basis. On the contrast, milk powder factory has to dispose product at room temperature itself, and not on daily basis. The wide variation in the scale and method of disposal of the products does have a bearing on the location. For example cheese manufacturing needs cow milk. Hence the location of cheese factory should preferably be in cow milk producing area. A market milk plant that handles only fluid milk should preferably be located in a city or its outskirts due to the following reasons: 1. Nowadays good transport facilities are available, that connect the country milk shed areas to the cities 2. Even after pasteurization, milk has got a lower shelf life when compared to other products, hence it should be disposed as soon as possible 3. Bulk transport of pasteurized milk can increase the chances of contamination 4. If glass bottles are used which are to be returned for re-use, location near the market will reduce the costs 5. Increased advertising value of the plant, when it is near the market Usually space is allotted for dairy plants in the industrial areas; hence environmental aspects are to be considered as Industrial areas tend to be highly polluted. Preferably the plant should be located on a side road to a major road, because 1. Easy access to the major road 2. Pollution, noise and dust of major road avoided 3. Traffic blocks won‟t create a problem at the gate for incoming and outgoing vehicles 7.2 Location and site selection for dairy plants. The problem of selecting a location for a dairy plant has been given considerable thought by many authorities. Selecting a location involves large commitments of capital, as a result it must be done with the utmost care. The Dairy Plant Design and Layout www.AgriMoon.Com 22 problem involves selecting a region as well as specific site within that region. The most difficult part of a plant location analysis is determining the criteria by which various location alternatives can be evaluated. 7.3 Location of Milk Products plant: The location of milk product plant is decided based on milk product consumption, availability of milk, and other services required. It is advantageous to locate manufacturing plant close to areas where surplus milk is available after meeting the daily requirement of liquid milk. The activities of milk product manufacturing should be centralized to get advantage of economic handling of fluid milk, seasonal surplus milk and milk products with a better management control. A few points mentioned below will help in determining the location milk product of plant: (i) The plant should be located at a place where transportation facilities are available, such as railway siding or near highway. It should be noted that, suitable site would always provide easy transport of raw material to the plant and disposal of finished products. (ii) To avoid contamination, the bulk transport of pasteurized milk should be discouraged. If pasteurized milk is to be distributed in glass bottles or small containers which are to be returned for reuse, the dairy should be situated close to consumption area. For any reason, if dairy is situated far away from consump tion area, it is necessary to transport bottled milk in large quantity to local depots equipped with cold storage facilities. (iii) Advertising value also affects the location of the plant. For instance a plant installed by the side of a heavily traveled highway naturally commands good sales. (iv) Location of building should be such, that, all necessary services e.g. electricity, water, waste disposal are available at reasonable cost. (v) The site must be large enough and of suitable shape to give freedom in planning the building and to allow space for future expansion. (vi) The area should be free from atmospheric pollution. (vii) Adequate labor must be available at site and it may be necessary to provide housing facilities to workers. (viii) Traffic congestion around the plant should always be avoided. Larger plant will require more land for smooth control of traffic pattern. For any entrepreneur desirous of setting up a dairy industry, it is advisable to go through the following check list on „Location‟ to assess its suitability. A milk product plant can be located preferably in a village location due to the following reasons; 1. Proximity to the milk shed, reduced transportation cost for raw material 2. Increased shelf life of the product when compared to the raw material 3. Availability of cheap land and labor 4. Reduced noise and pollution Dairy Plant Design and Layout www.AgriMoon.Com 23 5. In many cases the volume of the final product is less than the milk used, hence reduction in transport and handling cost eg: Cheese, Butter 6. Solid products can be transported in trucks 7. Some products doesn‟t even require cold-storage. ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 24  Lesson 8 Site Selection 8.1 Introduction: Once the broad location for the dairy plant is decided, within that limited area of location, a site is to be chosen depending on some factors that maximize the operational flexibility and minimize the operational cost as well as contamination. The site should also be selected keeping in view the future expansion of the plant. Before any work can be done on the building‟s design, a site for the plant must be chosen, which requires careful thinking. If the site is wrongly chosen, it may lead to a costly venture and difficult to correct situations such as: 1. Heavy transportation rates for incoming and outgoing materials from the plant 2. Heavy cost for labor and difficulty in having services like water, electricity and waste disposal 3. Reduced profits due to competition for getting raw materials as we ll as sale of products. 4. Legal complications if the local community objects to have the plant in the area 5. Restricted future expansion due to site conditions 8.2 Selection Criteria for dairy building site After selecting the general location for the plant, one needs then to select the actual site on which the building can be constructed. In order to make this decision one needs to consider the following: (i) Whether a sloping or level site is required? (ii) Access to the location - are roads suitable and is a rail link required? (iii) Has the land or site been contaminated and what is the underlying geology? (iv)Will planning permission be granted? (v) At what level is the water table and what is drainage like? (vi)What utilities are available - water, gas, electricity, etc. (vii) Security, in particular access and boundaries. Since dairy plant and products and products manufactured in it have direct public reaction, it is therefore important, that, the site should have a good landscape. Advertising value plays a great part in site selection as well as in external plant appearance. To have a good business and sales, it is suggested to have a thorough check up on the topography of the place and the other factors. Dairy Plant Design and Layout www.AgriMoon.Com 25 Topography of the site means detail description or representation of natural and artificial features on the map of the place where dairy building is to be constructed. The topography will immediately point out to local services available, location of the sewer line, municipal water lines, zoning and planning of area, restrictions, conditions obtaining in the area and nearby surrounding etc. After studying topography of place, necessary corrective measures may be taken to ensure the suitability of the site Some typical factors for site selection include size of area available, layout and orientation, drainage, freedom from flooding, any utilities already in place, subsoil, excavation and foundation considerations. Further, Gullies, streams etc. have to be bridged. Any abnormal grading or landscaping problems, any pipelines or other utilities to be relocated. approach to main road and highway. Certain commercial services near the site selected, which are to be considered include facilities for major repair shops, electric motor maintenance, product distr ibutors, lubricants, sanitary materials, engineering department supplies, stationary, local trucking, railway, postal service, air conditioning service and professional service. The site selected for dairy plant should be suitable for space requirements as well as for the needs of future expansion. The cost of site should be considered together with the development cost, including such items as the provision of rail road or dock if waterfront site is selected. The availability of drainage facilities and the costs of sewage disposal should be checked. Level and firm bottom land is desirable for all sites. The character of the underlying strata and their suitability to support structures at low cost should be considered. Soft underlying formations increase costs because expensive piling is required. Although top-rock formation raises the cost of constructing sewage disposal system, pipelines undergoing tanks and deep foundations required for equipment, it reduces cost of building construction. The cost of plant, therefore, is to some extent determined by the site. The shape and size of the land plot on the site may have an important influence on the layout. It must allow for possible future expansion requirements. The plot plan of the site should be developed in such a way that there is no wastage of areas. It is important, that the nature of ground at the site conforms to certain requirements. The upper layers of the soil must allow easy drainage as is the case with gravel, sand and the like, so that, water quickly disappears from the surface. At the same time, the ground should provide a firm foundation for roadways and surfaced areas. The subsoil should be firm at the depth for the foundations of the building. Sites with loose clay, shifting sand or high water table should be avoided, as the foundation work on such ground will be both expensive and time consuming. Before making a final choice of site, trial holes should be dug where the building is to be erected. At the same time the subsoil water level in the wet season should be checked to make sure that it is at an appropriate depth. It is also necessary that the site selected should have transportation facilities, so that, raw material can be easily transported to the milk processing plant and disposal of dairy products to local depots, milk booths or milk parlours does not pose any problem. Delivery trucks, insulated milk tankers, and other vehicles directly or indirectly related to dairy factory should have ample parking space at site along with garage facilities for washing and lubrication. There should be wide roads, and traffic pattern has to be planned in such a manner at site so that, incoming vehicles do not block the passage of outgoing vehicles. Site should have convenient approach from main road or highway. If the site selected is near railway station, it will be beneficial to have railway siding touching the dock at dairy plant. In addition to the dairy company deciding if a site is suitable to meet its requirements, the impact of the factory on the surrounding area needs to be assessed. The normal method of assessing the impact of a factory on the surroundings is to carry out an environmental impact assessment. In addition one may also wish to carry out lifecycle analysis. The assessment should include the following key issues: (i) Waste disposal (ii) Potential hazards to local community Dairy Plant Design and Layout www.AgriMoon.Com 26 (iii) Pollution - gas, liquid and solid (iv) Noise levels - day and night (v) Effect of the facility on the use of local raw materials (vi) Transportation infrastructure 8.3 Planning the dairy building on site: 1. Locate the building about 45 m back from highway. This will allow some space surrounding the building even after a highway-widening project. 2. Traffic should be planned to ensure safe movement of all vehicles and pedestrians. Places where pedestrians need to cross roads should be avoided. Truck and automobile driveways should be segregated close to the entrance with clear distinction for visitors. Soiled vehicles that could pose a sanitation risk to the product should be routed in a different way to avoid contamination. Roads should be kept in good condition to avoid damage to products in transit. 3. Provide driving access to all sides of the buildings, if possible. This allows for one-way circulation and will allow fire-fighting vehicles to have access where needed. 4. Rail sidings, parking lots for trucks and automobiles, trash collection areas, and “surplus” equipment dumps can become a source of contamination and a breeding place for vermin. These areas sho uld be kept groomed and drained to prevent contamination to food products by seepage. 5. Locate loading bays at the rear of the building. A gentle slope from the front to the rear will cause the floor of the building to be about 1 m above grade without cutting or filling. 6. Grade the site for natural drainage to ditches. In some areas, grading must be done so that all surface water will be channeled into a storm drain system. Surface water must never be allowed to enter the waste drain system, because water treatment costs are also based on volume. 7. Provide access to the truck building and weigh scale. 8. Locate employee and visitor parking at convenient entry points to the building. 9. Truck parking should be separate from the other parking areas and co uld be fenced. 10. Raising outside equipment about 20 cm above the pavement will prevent it from being used by rodents as a breeding place. 11. Landscaping and gardens contribute to the company image. Good planning will ensure low initial costs and low maintenance costs. Small recreation areas outside of the plant improve employee morale. Employees should eat in the space provided for them and should not take food outside. Dropped food attracts birds, rodents, and insects, and feeding stray cats or birds on site should be prohibited. 12. Around the base of the buildings, a 1 m grass- free strip covered with gravel or stones are advisable. This controls weeds and is a good area for placing traps and bait. Dairy Plant Design and Layout www.AgriMoon.Com 27 13. The perimeter should be fenced for security reasons and to prevent children from entering the grounds. This is important if bait-accessible bait boxes are placed outside the plant. Chain- link fences, more than 2 m high, are normally sufficient. The fences will catch pieces of paper, and cleaning them must be part of the overall housekeeping on the site. 14. Orient the building so that its best features and sign face the busiest street. ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 28  Lesson 9 Location of Milk Product Plant 9. 1 Introduction The location of milk product plant is decided based on milk product consumption, availability of milk, and other services required. It is advantageous to locate manufacturing plant close to areas where surplus milk is available after meeting the daily requirement of liquid milk. The activities of milk product manufacturing should be centralized to get advantage of economic handling of both fluid milk, seasonal surplus milk a nd milk products with a better management control. The location of the plant is as per the requirement of dairy machinery and its installation requirements, which decides the building should be of single storey or multi- storey and accordingly site is selected looking to the topological requirements considering water level and application of super structure concept for the building. 9.2 Classification of Dairy plants · Product Milk Plant Here, there is the production of products like cheese, butter, ice-creams, etc. which do not require daily distribution to the consumers. So the plant should be located near the producing areas. The difference in the location areas of both plants results in the minimized transportation cost. Milk plants can be classified based on its capacity: · Small Capacity Milk Plants These are usually on ground floor i.e., one level like for liquid milk plant. The milk storage tanks can be easily be placed in the processing rooms. Also the laboratory is connected to the milk reception room. The despatch should be placed next to the storage. The arrangement should be such that keeps the flow in view and all pipes should be kept as short as possible. A wall should be made in such manner that allows a provision for future expansion. · Medium Capacity Milk Plants The capacity of the medium sized dairy plant ranges from 20,000 lit to 1, 00,000 liters of milk handling per day. Layout for products like market milk, butter & ghee and cheeses can be designed. Each room should be planned separately and arranged with forward flow of product as per requirement. · Large Capacity Milk Plants Here, the plant building may have few floors having multi-product manufacture, where the reception is done at the ground floor and should have both milk treatment and tank storage on the first floor. If products like milk powder are to be manufactured, then the powder plant should placed in different building. A few points mentioned below will help in determining the location of milk product plant: (i) The plant should be located at a place where transportation facilities are available, such as railway siding or near highway. It should be noted that, suitable site would always provide easy transport of raw material to the plant and disposal of finished products. Dairy Plant Design and Layout www.AgriMoon.Com 29 (ii) To avoid contamination, the bulk transport of pasteurized milk should be discouraged. If pasteurized milk is to be distributed in glass bottles or small containers which are to be returned for reuse, the dairy should be situated close to consumption area. For any reason, if dairy is situated far away from consumption area, it is necessary to transport bottled milk in large quantity to local depots equipped with cold storage facilities. (iii) Advertising value also affects the location of the plant. For instance a plant installed by the side of a heavily traveled highway naturally commands good sales. (iv) Location of building should be such, that, all necessary services e.g. electricity, water, waste disposal are available at reasonable cost. (v) The site must be large enough and of suitable shape to give freedom in planning the building and to allow space for future expansion. (vi) The area should be free from atmospheric pollution. (vii) Adequate labor must be available at site and it may be necessary to provide housing facilities to workers. (viii) Traffic congestion around the plant should always be avoided. Larger plant will require more land for smooth control of traffic pattern. For any entrepreneur desirous of setting up a dairy industry, it is advisable to go through the following check list on „Location‟ to assess its suitability. A milk product plant can be located preferably in a village location due to the following reasons; 1. Proximity to the milk shed, reduced transportation cost for raw material 2. Increased shelf life of the product when compared to the raw material 3. Availability of cheap land and labor 4. Reduced noise and pollution 5. In many cases the volume of the final product is less than the milk used, hence reduction in transport and handling cost eg: Cheese, Butter 6. Solid products can be transported in trucks 7. Some products doesn‟t even require cold-storage ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 30  Module 4. Planning and principle of dairy plant layout Lesson 10 Importance of planning and principles of dairy plant design 10.1 INTRODUCTION Dairy Plants are engaged in processing of milk and manufacture of various dairy products. It is estimated that about 20-25 % of the milk produced in India is being processed by organized dairy plants. The planning of dairy and principles of dairy plant layout mainly depends on the type of the products manufactured and the capacity of the plant. It is necessary to consider both the supply of raw milk and market for processed milk. The earlier concept of locating liquid milk plant near the urban areas is changing and the trend is to locate the plant where the availability of milk is more. The availability of manpower, transportation, source of water and disposal of effluent are also to be considered for the planning of dairy plant. Dairy processing plants can be divided into two categories. · Fluid milk processing plants involving the pasteurization, flavored milk, butter milk, dahi, paneer etc. · Composite product plant engaged in processing of milk and manufacture of different products such as cheese, butter, milk powders, frozen products etc. Dairy processing aspects are changing continually and many new technologies are being used in dairy industry in order to improve productivity, use of automation, manufacture of value added products and conservation of energy. 10.2 Raw Milk Collection and Reception The milk is collected from the milk producers‟ society and the collected milk in milk cans is transported through truck to milk processing plants. As the time spent for transportation of milk from remote places together with warm environmental conditions, the sour milk percentage was higher. Therefore, the concept of establishing chilling center at appropriate location came in to existence to cool the milk in the respective chilling center and the chilled milk is transported to the milk processing plant. When the milk is received in cans, it requires milk reception dock having facility of milk weighing, can conveyer, can washer etc. is required at planning stage of dairy plant. Conversely, chilled milk collection and transportation in insulated tanker requires bay to unload the milk from the tanker. The present trend is to chill the milk immediately as soon as it is received at the milk producers‟ society by using BMC which has improved the quality of raw milk received on the plant. Therefore, based on the way of reception of milk, different principles are required for dairy plant layout. The capacity of the plant and level of automation required in the plant are also important in design of dairy plant. It is also necessary to consider CIP method at the stage of planning a dairy plant. Source of water and its distribution is a factor to be considered at planning stage of a dairy plant. Depending on the method of milk collection and reception, it is necessary to plan the reception dock. 10.3 Processing of milk The equipments such as milk pasteurizer, separator, homo genizer, cream separator, etc. are required to be installed in the processing room. The planning of this section is carefully done considering size of the Dairy Plant Design and Layout www.AgriMoon.Com 31 equipments and working space required for ease of operation. Cream separator and bactofugation require more working space in order to dismantle and assemble these equipments. This section also requires to accommodate milk pipelines to transfer the milk. In many dairies, the cream separation and clarification is carried out using self-cleaning separators. The separator also discharges sediment consisting of dirt particles, udder cells, and bacteria, and leucocytes, which normally is collected or led to the wastewater drain. 10.4 Manufacture of dairy products The product mix of the dairy is very vital to decide the planning of dairy plant. The product mix may be cheese, butter, milk powders, etc. The planning of various sections considering size of equipment, space requirement etc. should be considered. The housing of milk condensing plant and spray drying plant requires detailed specifications at the stage of planning of dairy plant. The height of the building and provision to access all components of the condensing and drying plant is one of the important requirements in planning of this section. All heavy equipment such as batch type of butter churn may be installed on ground floor with adequate strong foundation. 10.5 Importance of planning and principles of dairy plant design It is very difficult to develop perfect plant layout for all categories of equipment and services. The ideas of several persons are usually required to make a planning of a dairy building. The provision of future requirements is also to be considered as far as possible. It is noticed in many plants that it is not possible to install a single HTST plant in the existing building to handle more milk. Therefore, it is necessary to consider additional capacity requirement for the next 5-7 years. The adequate provision for offices, laboratory, storage etc. is one of the essential requirements in the planning of dairy plant. The dairy plant layout involves room arrangements and equipment layout considering all technical aspects. Thus, planning is the way of proceeding or scheme of arrangement for executing any work or project. Planning of dairy plant and adopting principles of design play an important role in the successful running of a dairy plant with desired quality and quantity of output. A well planned design using salient principles of planning helps in following ways. · Convenience of working · Ease of handling the operation · Easy maintenance · Safety · Better productivity and labor saving Advantages of planning and principle of dairy plant designing are mentioned. · Better hygienic conditions and minimum losses. · Accommodation of future expansion · Reduction in processing cost · Optimal height reception dock improves the working efficiency of worker Dairy Plant Design and Layout www.AgriMoon.Com 32 · Safety of persons working in the plant. · Better use of services such as water, electricity, refrigeration, air supply etc. · Better space utilization for equipment and services.. · Quick communication with different sections of dairy. · Efficient utilization of manpower. · Efficient movement of product within the plant and dispatch · Energy saving · Saving on building cost Utilizing principles of planning and applying them for plant construction leads to economical and effective running of plant. The use of scientific, technical, and logical knowledge can form a model plant for dairy. The planning of dairy plant is more important as compared to other industrial plant due to the requirement of hygienic conditions and perishable nature of milk and milk products. 10.6 Dairy building planning The elevation of dairy building should give advertizing image to the people. The form and shape of dairy building is important as it affects the public reaction as well as upkeep and initial cost. In addition to several technical considerations, marketing of dairy products needs good site selection and attractive building design. Appearance and look are the primary factors affecting the marketing of the products. If a brand is having a typical pattern of building replicated at many places the building pattern itself may become identification for the brand of the organization. ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 33  Lesson 11 Dairy building planning 11.1 INTRODUCTION The planning of dairy building is the main activities for establishment of dairy plant. Planning is the way of proceeding or scheme of arrangement for executing any work or project. Designing a dairy plant layout is a joint venture of Architects, Dairy Managers, Dairy Engineers and Administrators. It is necessary to consider all technical aspects and economical considerations. The ideas of several technocrats are sought and based on the suggestions of all concerned, actual building planning is worked out. The requirement of utilities such as water, refrigeration, steam, electricity etc. is carefully estimated while planning a dairy. The planning of dairy building depends on capacity, product mix, size of equipments, work space to be kept, future expansion requirement etc. There is no any blue print to be used for design of dairy building. It varies from plant to plant even though the capacity and product mix is the same. 11.2 Dairy plant layout The main objective of dairy plant layout is to design the dairy plant to carry out all dairy processing operations. The knowledge of estimating the requirement of various equipments, location of equipments in different sections, space requirement for equipment and the general civil aspects of building construction. The engineer should have very clear and complete understanding of requirement and management policies. The management policies decide the future expansion requirement of a dairy plant. Management decision with respect to the addition of new of products is important to be considered at the stage of dairy plant layout. It also includes process schedule to be followed and requirement of different utilities. A well designed layout must facilitate production operations, minimize material handling maintain flexibility of the operation for alteration and expansion, minimize investment in equipment, make economical use of floor area, promote effective utilization of the labor and provide for employee convenience and comfort. It is up-most important to design optimum size of dairy building. Some enterpriser engages an architect to prepare the plant layout for an attractive design and consult dairy equipment manufacturers for ideas regarding latest machinery. However, involvement of dairy engineer in the layout is very vital to take care of all necessary requirements. It is advisable to make judicial use of land available and optimum cost in construction of building. 11.3 Important factors for planning of dairy building The following are the basic factors which must be considered before planning the dairy building.  Milk handling capacity and variation in milk handled every day.  Method of milk collection and transportation  Design of milk processing section.  Method of milk packaging.  Way of milk distribution to consumers  Source of electric power supply, water supply and waste water disposal.  Type of fuel for boiler.  Provision for subsequent future expansion.  Transportation facilities and conditions of road Dairy Plant Design and Layout www.AgriMoon.Com 34 The source of water throughout the year is very important in design of the plant. Water may be distributed by gravity system or hydro- flow system using G.I. pipelines. If power shut down is frequent, then provision should be made for standby availability of electric power. It may not be possible for large plant to have diesel electric power generator for total load of the plant. But partial requirement of electrical power generator facilities is necessary to carry out essential low power consuming opera tions. The method of effluent treatment system is to be considered at the design stage of the building and provision is made for disposal of treated water. 11.4 Planning of dairy processing schedule Process scheduling means arranging the flow of products through various operations in the plant in order to achieve maximum use equipment and labor, and the processing of the products is accomplished in the shortest possible time with minimum delays between processing of different products. 11.5 Ope rational layouts Operational layouts describe operations which take place in processing or manufacture of different products. All operations involved are represented diagrammatically in chronological way (sequence-wise flow diagram) which can be easily understood by a layman. Even operational layouts can be shown in pictorial views or three dimensional layouts. Such layouts would help to understand the sequence of operations to be followed for the manufacture of various products. 11.6 Principles of dairy layout A dairy plan engineer should try to incorporate all the fundamental aspects listed below. This would help in performing dairy activities economically and efficiently. 1. The milk path should be as short as possible. This will minimize the cost of pipeline and clea ning time. 2. Reception and dispatch must be arranged in such a way that congestion of transport vehicles is avoided. 3. As general guidelines, a small dairy may have reception and dispatch on one dock but it is necessary to have them separate for large dairy plants. 4. Where space is available, single storey building is most suited. The plan may have a rectangular shape with roads on all sides. 5. Location of milk silo outside the building area may save space and construction cost. This is widely followed in almost all dairy plants. 6. As far as possible refrigeration and boiler section are kept little away on the side of the building on ground floor. Refrigeration machinery room should be near the process room and cold store to reduce the piping cost and pressure drop. 7. Laboratory should have easy approach to reception room and processing room. 8. Separate building block for administrative offices Dairy Plant Design and Layout www.AgriMoon.Com 35 11.7 Product storage There are two types of storage rooms required for dairy plants. · Products stored at room temperature e.g. milk powder · Products stored at lower temperature e.g. milk, butter, ice-cream, cheese etc. The design of cold storages requires careful planning to store the product at lower temperature. Pasteurized milk is stored at 3-4 ⁰ C while ice-cream is stored at – 25 ⁰ C. Therefore, separate cold storages are required for different dairy products. The capacity of cold storage and cooling load calculations are necessary for the design of the cold storages. The frequency of dispatch and period of storage required are essentially required for design of the cold storages. 11.8 Selection of equipment The selection of equipments before the actual design of building is necessary to decide the space and input required for these equipments. Some equipments are very large which are required to be installed before the construction of walls of the building. The distance to be kept between the equipments is also important to decide the ease of opening the equipment for maintenance purpose. Specifications of each equipment is necessary to be decided at the time of planning of dairy building. ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 36  Lesson 12 Preparation of process schedule 12. 1 INTRODUCTION: Process schedule is one of the important activity of planning, before diverting milk to different section for product manufacturing. It is prepared well in advance to give instructions to boiler operator, refrigeration plant operator, different process section in charge to plan for the activity of different unit operations for processing the milk to have smooth operation of the process. It also helps to prevent product losses and to have efficient use of equipments, energy and water. 12.2 PLANNING FOR PROCESS SCHEDULE Preparation of process schedule is one of the important tasks in dairy for a technologist in order to prevent losses in terms of manpower, energy, services, and time. A well planned time schedule will help in preventing losses as well aid in routine work viz. Maintenance, breakdown, establishment etc. After careful consideration of dairy building planning mentioned above, a process scheduled layout is drawn. Process scheduling means arranging the flow of products through various operations in the plant in such an order that maximizes use of all labor and equipment, and the processing of the products is accomplished in the shortest possible time with minimum delays between processing of different products. First of all “Basis of Dairy Layout‟ is drawn according to item of manufacturer to decide definite line flow. To this skeleton layout are added as other information, such as operating rates, storage capacity, raw material required, man power required etc. as each section of plant is considered in relation to the equipment available. Planning for operations involved in processing of any dairy product has to be done in advance so that maximum use is made of men and material with little waste of time. Process schedule which is more or less work plan ensures that the proposed operation will run smoothly. It provides the basic information from which schedule of service requirements and list of equipment can be made. Time and operation graph can be made w hich will indicate at what time particular operation has to be performed. It may be noted that all operation for manufacture of any particular dairy product cannot be started at time. There must be a sequence for performing an operation in the plant and that is why the process schedule is required. The features of the plant considered during preparation of process schedule are: · Reception capacity, · Unit processing cost, · Frequency of CIP, · Installed capacity of the plant, · Handling capacity of the plant, · Running hours and Idol time of plant, Dairy Plant Design and Layout www.AgriMoon.Com 37 · Quantity of milk received in different season, · Capacity of the various equipments installed for the processing and production purpose viz. PHE, SEPARARTOS, PUMPS, CATLES, VAT, etc; · Capacity of the services and providing machines viz. Air compressor, refrigeration, boiler, water, ETP, etc; · Product dispatch timing 12.3 Example of a Process schedule of a milk-processing plant handling approximately 1.5 lakh lit of milk in morning and evening: Milk is received two times in a day approximately 82,000 lit in evening and 68,000 lit in the morning. Considering the processing capacity of the plant 20,000 lit /hr. Dairy Plant Design and Layout www.AgriMoon.Com 38  ****** ☺****** Dairy Plant Design and Layout www.AgriMoon.Com 39  Lesson 13 Space require ment for dairy plant 13.1 Introduction The space requirement for dairy plant should be estimated for its functional design to have smooth operation. The space requirement of entire dairy plant is estimated by adopting principles of dairy plant layout. It is a basic requirement to estimate the total area required for the dairy plant which include building area, parking, movement of vehicles, roads, ETP etc. The type of layout varies considerably for the same plant after having estimated the space and area requirements for different sections. Land requirement is one of the basic cost factors of the plant and land cost has increased considerably in last decades. Therefore, it is important to design the plant with cost effectiveness. According to size and shape of the plot, the most befitting type of layout is selected and all sections are planned in accordance requirements. 13.2 Area and space require ments for milk plants Space required for equipment depends upon the capacity and dimensions of the equipment. There is no any rigid rule to decide the area of various sections. It mainly depends on the idea and judgment of engineer who is designing the dairy plant. General guidelines are given below to estimate the size of different sections. Dairy Plant Design and Layout www.AgriMoon.Com 40 Bulk milk storage: The space requirement for bulk milk storage can be estimated based on the type of storage vessels used (horizontal storage tank, vertical storage tank, silo etc). The space requirement is estimated based on the working space required around the tanks and necessary equipments installed around the tank. It should also facilitate the cleaning operation, manually or CIP. Dairy Plant Design and Layout www.AgriMoon.Com 41 13.3 Space requirement for different sections of dairy plant: Allotment of the space for the specific section and to the specific plant and equipment is a matter of thinking so as to provide sufficient space to each plant and equipment for better functioning at the place for worker. Less space will create congested atmosphere and may cause accident at work in hurry some time; whereas unnecessarily providing more space may cause shortage of land in future and will cost more for maintaining cleanliness. So the space provided for a section should be sufficient enough for working freely and comfortably, which should be planned well with concept of expansion in future also. The sections like boiler, electricity and refrigeration should be kept in isolated area to safe guard the plant from accident and damages The decisive factors which are to be kept in mind during construction of plant for space are: · Size and the capacity of the equipment i.e. Height, length, width, etc. · Type of operations to be carried out · Future expansion Dairy Plant Design and Layout www.AgriMoon.Com 42 Dairy Plant Design and Layout www.AgriMoon.Com 43  Lesson 14 Estimation of service requirements including peak load consideration. 14.1 Introduction Estimation of service requirements is important to determine the capacity of equipments used for providing different services in the dairy plants. The major utilities of dairy plants are steam, refrigeration, electricity and air supply. It is necessary to know rate input services required for various equipments. The peak load can be estimated by for various services based on the operating schedule of the equipments. The peak load estimation is also important to make contract for connected electrical load of the dairy. The peak load requirement for steam, refrigeration, electricity and effluent treatment plant is very much necessary. Peak load is calculated based on capacity utilization of equipment and load conditions of cold store, ice bank tank and effluent treatment plant. Dairy processing plants are traditionally divided into two separate categories for the purpose of production and energy statistical data presentation: fluid milk; and industrial milk. These two categories are described as follows: · Fluid milk processing involves the pasteurization and processing of liquid milk for direct consumption, as well as creams, chocolate and other flavored milks, and buttermilk. · Industrial milk processing involves the processing of milk into value-added products. These include cheese, butter, ice cream and other frozen products, condensed and evaporated milk, dried milk powder, yogurt and other cultured milk products. The milk used in the manufacture of industrial milk products is also pasteurized before processing. For the purpose of this guide, six major generic process sequences (one fluid and five industrial) have been considered. These processes are: o Fluid milk; o Cultured products; o Cheese; o Butter; o Ice cream and other frozen products; o Evaporated/dried products o Traditional Indian dairy product. These generic process/product combinations were selected because they: · Cover the wide range of product manufacturing activities undertaken; · Represent the natural groupings of similar generic processes; and Dairy Plant Design and Layout www.AgriMoon.Com 44 · Coincide with the general process categories separately modelled in support of Hazard Analysis Critical Control Points (HACCP). 14.2 Steam Requirement Steam requirement is calculated for processing and other purposes separately, while boiler for condensing and drying plant is selected separately, based on the calculation of steam requirement in the condensing and drying plants. After estimation of steam requirement of each equipment on hourly bases, time schedule diagram including each processing equipment is prepared to know the peak requirement of steam in the peak hours. Depending on the peak load requirements, steam pressure is maintained and boiler is started in advance to get required steam pressure and quantity of steam. The main steam line pressure is maintained higher than actually required during peak load hours, considering losses in the lines and number of bends in the line. The fluid milk plant requires approx. 0.25 to 0.4 kg of steam per liter of milk, while that of powder plant requires app rox. 5 kg of steam per kg powder. 14.3 Refrigeration Require ment Refrigeration requirement of dairy plant is mainly divided into two major categories (i) Chilling load and (ii) Cold storage load. Chilling load is referred to the chilled water requirement o f different equipments during processing of different products. It is calculated based on the chilling requirement of different processes. The chilled water requirement of different processes can be met by Ice Bank Tank (IBT) or Ice Silo. IBT can be designed based on the total requirement of chilled water in the different processes in a day. The refrigeration plant for IBT can be operated during night hours (16 to 18 hours a day). The cold storages are required for different dairy products like ice cream, b utter, cheese, milk etc. They are maintained at different temperatures and at different relative humidity depending on type of product to be stored. The cold storage refrigeration plant capacity is calculated based on consideration of different types of loads like product load, wall gain load, air change load, lighting load and miscellaneous load. Time schedule for different processes which, requires chilled water is prepared to know peak load requirement of chilled water. Similarly time schedule for loading and unloading of the cold storages are also prepared to know peak load requirement of cold storages and accordingly refrigeration plant is operated to conserve energy. 14.4 Electricity Require ment Electricity requirement for different equipments, pumps, motors, refrigeration plants, lighting and general purpose is calculated based on actual operating load. Depending on the requirement of single phase and three phase connections load distribution is made using necessary controls. All the equipments are pro vided with safety devices to protect from over load condition or voltage fluctuations. Motors are provided with variable frequency drives and soft starters to conserve energy. Refrigeration plant of dairy contributes approx. 40 to 50% of total electricity load. 14.5 Wate r Require ment Water supply for dairy plant is important and must be considered at the planning stage. An adequate supply of pure water for washing of equipment and cooling purpose is essential. An ideal water supply is one that is soft cold and free from all impurities. The water is treated to meet plant requirement by using suitable process. The hardness of the water used in the dairy plant should be maintained below 35 ppm. Generally the ratio of milk: water of fluid milk plant is 1:1, while that of multi product plant is 1:1.5 or 1:2. It depends on type of products made and size of the plant. There are different types of water soft water, well water, chilled water, hot water etc. they are used in the different processes, for cleaning of equipment and floors. The distribution of water can be done by gravity, centrifugal pumps or by hydro flow systems. Hydro flow system is used to have uniform pressure in the water pipe lines, which facilitates operation of automatic control systems. Control of use water is Dairy Plant Design and Layout www.AgriMoon.Com 45 required to conserve water and to reduce load on effluent treatment plant. Dairy Plant Design and Layout www.AgriMoon.Com 46 Dairy Plant Design and Layout www.AgriMoon.Com 47  Module 4. Design aspects of dairy plant Lesson 15 General points of consideration for designing dairy plant 15. 1 Introduction Dairy industry in India is growing at fast rate and as such, there is need for Scientific Layout and Planning with a view to have model studies by dairy designers, engineers and architects. The term „Dairying‟ has been bifurcated into two branches, namely Dairy Husbandry and Dairy Technology. Under the purview of dairy husbandry comes animal breeding, care, health, nutrition of animals, animal housing, clean and safe production of milk, i.e., mulching animals in good sanitary conditions. In some organized sectors, milk collection a nd chilling before milk is transported for processi9ng at dairy factory also forms an activity of dairy husbandry. The Dairy Technology commences with processing of milk at dairy plant for market milk and various dairy products. The dairy plant layout and design means designing a layout plan for dairy factory, i.e. layout of various sections in dairy building, equipment layout, laying of dairy machines in each section for economical and efficient movement of men and material in the plant. It will deal with all items which are needed for planning and layout of dairy factory, with direct application to fundamental topics, such as location, selection of site for dairy plant, building materials, specific requirement of each section including service sections. It will also touch the practical need of prospective entrepreneurs aspiring to set up a dairy plant. Management and planning of layout of indirectly related sections, such as office and administration block will also find place in this presentation. The treatment of subject matter is descriptive and lucid so that students, teachers and dairy professionals can imbibe the topics discussed easily. Many illustration and diagrams have been given to make the subject crystal clear. Thorough study of the text book will not deprive the learner of various definitions of milk and milk products, terminology of various processing and technical terms as are commonly spelled in dairy technology and engineering. Milk and milk products, however, impose certain requirements which do not occur elsewhere in food or other industries. These special requirements affect the structure and the layout of the building, the provision and distribution of services and the choice of site. The products of dairy industry – milk for liquid consumption, yoghurt, curd (dahi), cream, butter, ghee and similar products, cheese, milk powder and so on – are foods which play a fundamental part in human nutrition. In any country, therefore, it is in the nation‟s interest that milk and milk products be available to everyone at the lowest possible rate. The margin of profit which the dairy entrepreneur can expect is limited. Therefore, every possible economy in capital outlay on building and plant should be sought. Planning must be done wisely to make best use of the labor employed and to keep operating costs to a minimum. Materials and method used in building must be such as to give the longest practical life with the minimum of maintenance, in spite of working conditions which are often relatively severe from both the mechanical and chemical points of view. It should also be seen that most of the repairs, alterations or extensions could be done without stopping the production. These characteristics demand closest attention during planning. There is need for highest standard of hygiene. Milk is most suitable medium for the growth of microorganisms; therefore, every possible measure should be taken to reduce the possibility of contamination, especially after processing. Failure to maintain adequate control of hygiene will spoil the product, it may not keep well or its flavor may change. This will pose problem to sell the product. A good layout design and use of proper materials and techniques make great contribution towards hygiene. Proper cleaning and maintena nce of plant and building is essential, so that, there is no contamination. Care should be taken to provide adequate natural and Dairy Plant Design and Layout www.AgriMoon.Com 48 artificial lighting. Every possible effort should be made to ensure that the building and the site will be pleasant to look at. The architect can provide a good landscape and an attractive outlook. The welfare of the employees must be kept in view. Canteen facilities are essential. Housing for key workers must be provided near the plant at reasonable distance, so that they can reach in time in emergency. To sum up, dairy plant layout needs careful thought and planning keeping in view manufacture of the products and their commercial aspects. 15.2 Increased safety and improved working conditions Good plant layout incorporates safety into the plant by eliminating hazards at work stations, in materials handling, storage activities, maintenance operations and the like. Man hour losses can be cut down to minimum. Reduction in losses of capital equipment and materials is another result of “built in” safety in the layout. The provision of a good physical plant environment improves the overall working conditions. Increased employee moral tends to reduce production costs and helps develop a stable operating force. 15.3 Peris hable nature of milk Milk by its nature is perishable. The following three factors contribute to its being perishable; (a) Contamination with bacteria (b) Warm temperatures, and (c) Prolonged time before cooling or processing In practice, none of these factors can be eliminated completely, so if any one is accentuated, the life of milk will decrease. Therefore, every effort must be made to minimize these factors on the farm, during collection at milk plant and during distribution to consumers. At the farm, the aim must be to cool the milk as soon as possible often milking. Freshly drawn milk has bacteriostatic property, i.e. it contains substances which resist the growth of bacteria for several hours. However, there is a substantial bacterial population. Ideally, the milk should be chilled to 4 o C within two hours after milking. If for any reason this can not be done at farm, quick transport of milk to the plant is essential. If milk can be stored conveniently at the farm or local collecting depot at low temperature, the organization of transport to milk processing plant is simplified to greater extent by transporting bulk quantity in insulated tankers. The type, size and number of vehicles necessary are, therefore determined not only by the usual factors such as distance or nature of roads but also by the condition of milk production. This applies to cream also. In some cases, the milk may be separated at the farm and only the cream, i.e., milk containing 5 to 30 per cent fat is sent to plant for manufacturing butter or ghee. 15.4 Flexibility Management should lay stress upon maximum flexibility in production facilities and distribution methods consistent with low cost operations. Production facilities and layout can be designed to attain flexibility and adaptability to meet changing economic and technological conditions. To combat regular fluctuations in the supplies of milk available to processing plant throughout the year, flexibility in the plant layout is essential. Flexibility is necessary since market conditions for the sale of finished products attain flexibility in production changes of the product, and technological advances must be anticipated so that plant equipment does not become obsolete. The amount of production flexibility depends on such factors as the nature of t he products, the kind of production facilities can in part be attained by initially selecting universal and standard types of machines, which can perform a variety of operations, such as Tri-process machine used for cream separation, Dairy Plant Design and Layout www.AgriMoon.Com 49 clarification and standardization of milk. Layout flexibility can also be attained by incorporating into the layout as much as possible the process- layout arrangement whenever it is consistent with low cost operations. Allowance for increases in capacity can be anticipated in a layout by properly arranging production departments and selecting the type of building that can be expanded at low cost. Sound layout engineering attains low cost flexibility in the kind of operations performed and an ease in the increase of output capacity which may be required for the future. Good plant layout achieves a floor arrangement that contributes in a number of ways to low-cost production planning and control. Materials control can be more easily attained in a well designed plant layout. A stead y amount of production capacity is facilitated an idleness of machinery and man is reduced to minimum. The net result is facilitation of dispatching activities on operating floor. Deliveries toi customers on short notices are easily attained. 15.5 Modes of transportation of milk A mode of transportation of milk depends on type of area, type of transportation available and local road conditions. Table 15.1 shows different types of mode of transport used for procurement of milk, for optimum load conditions and distance. Dairy Plant Design and Layout www.AgriMoon.Com 50 15.6 Milk procurement and reception at dairy plant In most of the countries, milk production is carried out in rural areas from where it is transported to milk processing plant, and thereafter for distribution to consumers through local depots or milk parlours. Under Indian conditions, milk has to be regularly collected and transported twice a day (morning and evening). The usual methods of milk collection and reception at dairy plant are: Milk procurement through individual producers: In this milk is brought to the dairy plant by the individual producers in their own vessels any type. This is possible for those producers who are located nearby milk processing dairy. Milk collected through co-operative organizations: Here, co-operative societies form an organization which is responsible for uninterrupted supply of milk to the dairy plant. Supply of milk can also be effected by single co- operative society formed by milk producers. This is beneficial to the producers as there is no middle man to share the profit. Milk procured through contractors: There is less return to the milk producers, as milk contractor will keep his share in the profit. Milk reception from milk collection cum chilling centers: This method is generally possible and is prevalent in organized sectors, and dairy corporations in India. Milk is collected at various milk collection centers from nearby villages in 40 litre cans usu