Occupational Safety and Environmental Safety for the Food Industry Lecture 5 PDF

Occupational Safety and Environmental Safety for the Food Industry Jennifer Campbell Lecture 5 © Innopharma  Module Overview This module aims to provide the student with comprehension of Health and Safety in the manufacturing industry, including the nature of hazards & their control, bi...

Occupational Safety and Environmental Safety for the Food Industry Jennifer Campbell Lecture 5 © Innopharma  Module Overview This module aims to provide the student with comprehension of Health and Safety in the manufacturing industry, including the nature of hazards & their control, biosafety, risk assessment, waste management, with emphasis on legal requirements. 5 ECTS Module Breakdown 70% Final Exam – 2 hours – TBC January 2025 (In-person) 30% Continuous Assessment – MCQ – Saturday 9th November (Online) Lectures 5x Evenings 1x Saturday Contact Details: [email protected] © Innopharma 2  Module Learning Outcomes LO 1: Discuss the role and responsibilities of employees, employers and regulatory agencies under national and international legal frameworks. LO 2: Explain the types of information contained in a safety statement & discuss the steps in its preparation. LO 3: List the different types of hazards, there routes of exposure, personal protection equipment, along with describe the term safety data sheet and explain the information it contains. LO 4: Discuss both the causes and categories of biohazards and contaminants, the importance of cleaning, and review the different methods of sterilisation. LO 5: Explain the waste management hierarchy, along with discuss the role and function of regulatory agencies. LO 6: Describe how waste material is classified and explain the different methods of treating/disposing of gaseous, liquid and solid waste. © Innopharma  Lecture 5 Waste Characterisation Waste Analysis Techniques Waste Treatment Gas Solid Liquid © Innopharma  Introduction to Waste © Innopharma  Waste Definition “Any substance that is required to be disposed of due to contamination, damage or spoilage” An industrial plant will result in the production of wastes that include: Solids Liquids Gases Hazardous Waste Non-hazardous waste © Innopharma Most waste – Non-hazardous that can be recycled Examples: o Waste packaging o Paper o Canteen waste o Office waste © Innopharma Some waste will be hazardous A waste is hazardous if it’s concentration, quantity, physical, chemical or infectious nature poses a threat to human health or the environment. Classified as hazardous if it is listed in the European Waste Catalogue and Hazardous Waste List. It must exhibit certain hazardous properties. © Innopharma EWC_code_book.pdf (nwcpo.ie) Some waste will be hazardous Examples: o Chemicals o Pesticides and medicines o Paints o Biological samples o Containers and packaging materials contaminated with raw materials or products o Contaminated PPE o Gaseous Waste o Liquid or solid residues from a process (process waste) o Sludge from waste water treatment plant o Electrical and Electronic Waste © Innopharma Waste In order to deal with the wastes once they are produced, it is essential to know the characteristics of that waste (condition of the IPC licence) This tells us whether the waste is hazardous or non-hazardous, and will influence the methods of treatment and/or disposal © Innopharma  Waste Analysis © Innopharma Waste Analysis A variety of analytical techniques are used to determine and measure the constituents of wastes. These include: © Innopharma  1 Chemical Analysis Involve carrying out chemical reactions and measuring specific chemical components in a material © Innopharma  1 Chemical Analysis – pH Determination Measures the acidity or alkalinity of a waste pH Meter Gives an indication of the types of treatment suitable for the waste stream. Also, possible reactions, if this waste is mixed with other wastes © Innopharma  1 Chemical Analysis – Biological Oxygen …………………… Demand (BOD) Measure of the amount of oxygen required by microbes to break down organic matter in the waste (at a defined temp/time) Represents the biodegradable portion of the waste. Measures: Amount of oxygen used, expressed in mg/l. Test takes 5 days to carry out (bacteria incubated for 5 days at 20°C) © Innopharma  1 Chemical Analysis – Chemical Oxygen …………………… Demand (COD) Measure of the amount of oxygen required to breakdown all compounds, both organic and inorganic (i.e. non-biodegradable as well as biodegradable), in the waste. COD can be determined more readily than BOD (Test takes 2-3 hours to complete). Measurement indicates: o Measure of the amount of waste in water o Indicator of water quality © Innopharma  1 Chemical Analysis – Chemical Oxygen …………………… Demand (COD) Microbes are more successful at removing the BOD portion of a waste than the COD portion. Therefore, the BOD:COD ratio value for the untreated waste and the final treated waste are very different. The BOD:COD ratio value can be used as an indicator of how biodegradable the waste is. © Innopharma  1 Chemical Analysis – Dissolved Oxygen Measure of the amount of oxygen dissolved in the wastewater. Usually expressed in parts per million (ppm). Test is particularly important for biological treatment processes. Oxygen is a critical factor and needs to be monitored on a regular basis. © Innopharma https://jmsequipment.com/aeration-basics-why-does-the-dissolved-oxygen-content-of-wastewater-matter/  1 Chemical Analysis – Nutrient Analysis ………………...........(Phosphate, Ammonia etc.) Measure the concentration of specific nutrients in a waste stream (phosphate content or ammonia content). These are essential requirements in a biological waste treatment system. BUT … very high concentrations of these nutrients in waste can adversely affect the biological treatment process. Also has adverse effects on the watercourses they are discharged into. High levels could lead to development of an algal bloom. © Innopharma © Innopharma  1 Chemical Analysis – Suspended Solids Measure of the amount of solid material suspended in wastewater. Measured by: o Filtering known volume through filter paper. o Measuring the dry solids that remain behind on the filter paper after the wastewater has flowed through. Concentration expressed in mg/l. Test takes about 2 hours to complete. © Innopharma  2 Instrumentation Techniques Employ instrumentation techniques to carry out specific analysis that can identify and quantify the material present in the waste stream © Innopharma  2 Instrumentation Techniques – HPLC & GC High Performance Liquid Chromatography (HPLC) and Gas Chromatography (GC) o Sophisticated instruments o Used to separate, identify and quantity the chemical components of waste. © Innopharma  2 Instrumentation Techniques – MS Mass Spectrometry (MS) Identifies chemicals based on their mass and charge. A very powerful analytical technique, especially when combined with chromatography. © Innopharma  2 Instrumentation Techniques – Total Organic Carbon TOC is a screening test that measures the amount of organic carbon in the waste sample. Gives an indication of the strength of the waste (dilute or concentrated) For a biological treatment system this will help to indicate the amount of food potentially available for the microbes. © Innopharma  2 Instrumentation Techniques – Atomic Absorption Spectroscopy The instrument technique measures the metal content of a waste stream (calcium, mercury, cadmium etc.) Liquid sample introduced into the flame and burnt. Then measure the amount of light absorbed at specific wavelength. Absorption is proportional to concentration. © Innopharma  3 Microbial Analysis – Analysis of Water Quality Determination of microbial counts in a sample of water. 100ml filtered under sterile conditions. Bacteria collected on a membrane. Membrane transferred to an agar plate, incubated (48hrs at 37°C). Count the number of colonies and determine CFU (colony forming units) count. High CFU = High levels of bacterial contamination in water sample. © Innopharma Drinking water quality testing using Membrane Filtration technique  Waste Treatment © Innopharma Waste Treatment Waste treatment techniques are used to change the: Physical Chemical Biological character of the waste. Treatment will: 1. Reduce the volume and/or toxicity 2. Change its physical form to make the waste safer for disposal in compliance with environmental regulations and conditions of the IPC licence. The selection of a treatment method depends on the quantity and form of the waste material. © Innopharma  Gaseous Waste © Innopharma Gaseous Waste A condition of the IPC licence that occupational air quality is monitored and controlled. Typically, the gaseous emissions from a plant can be divided into: 1. Particulate Emissions e.g. dusts, powders etc. 2. Gaseous Emissions © Innopharma 1. Particulate Emissions Arises from dispensing and processing powder/ granular materials. Ingredients fed manually into mixing vessels. Particulates can be small enough to get deep into the lungs. Associated with health problems including: Bronchitis Asthma Heart Attacks Particulate emissions are controlled by air extraction systems. © Innopharma 2. Gaseous Emissions © Innopharma Inorganic Emissions Usually associated with the stack emissions from boilers, generators and incinerators. Combustion of fuel will determine the type of emissions from the stacks. Emissions are monitored and controlled as a condition of the IPC licence. © Innopharma Organic Emissions Comprise of a large family of carbon-containing compounds. They are emitted or evaporated into the atmosphere. The major organic emissions are Volatile Organic Compounds (VOCs). These may arise from the use of volatile solvents in cleaning operations. VOCs can aggravate respiratory and heart illnesses and lead to kidney and liver damage, carcinogenic. © Innopharma Gaseous Emissions These can be further classified depending on their route of emission from: o Point sources o Diffused sources Point Source Emissions: Controlled emission points e.g. stacks of boilers. These are monitored as a condition of the IPC licence (incl. frequency and type of monitoring required). Diffuse Source Emissions: Dispersion of particles due to ineffective ventilation. Accidental emission points (e.g. bursting discs, pressure relief valves). Secondary emission points (wastewater treatment plants, cooling towers, storage tanks). Emissions escape directly into the air and are difficult to quantify. Risk assessment carried out to determine potential diffused emissions on site and control and emission reduction essential (under IPC) © Innopharma Treatment of Gaseous Waste A number of treatment systems available. Nature of the containment will determine the treatment process used. Methods: © Innopharma  1. Filtration Suitable for removing particulates and heavy metals from gaseous wastes. In many industries bag house filters are used. Highly efficient particulate arrestor (HEPA) filters. HEPA filters trap particulates on the filter media. A fabric filter bag similar to a vacuum cleaner bag Air passes through the filter media and is recycled back to the workplace Generates solid wastes will need to be treated PPE required to remove and dispose of bags or HEPA filter cartridges © Innopharma  HEPA Filter © Innopharma  HEPA Filter © Innopharma 42  2. Flue Gas Scrubbing The combustion process in boilers and incinerators produce flue gases containing various chemicals including acidic gases. These can be harmful to health. This flue gas needs to be thoroughly cleaned or scrubbed before it is discharged to the air. Acid solutions are often used in scrubbing systems to neutralize the acid gases. © Innopharma  2. Flue Gas Scrubbing © Innopharma 44  2. Flue Gas Scrubbing Typically consists of: A tower packed with specific media. An acid solution is sprayed in the top tower over the media. Contaminated gas is pumped in the bottom of the tower and forced upwards. The falling liquid splashes on the packing media and interacts with the contaminated gas. This gas waste can dissolve in the liquid which must be treated. © Innopharma This is gas absorption  2. Flue Gas Scrubbing Alternatively: The contaminant in the waste can be adsorbed onto the carbon. This is gas adsorption So the gas adheres to a solid medium such as activate carbon. So solid waste created has to be treated and disposed of. © Innopharma  Video © Innopharma 47  3. Incineration Incineration of gaseous waste is suitable for burning flammable materials such as: Organic vapours Organic dust Particulates By-products of the incineration process may be produced which in turn need treatment prior to release © Innopharma 48  3. Incineration © Innopharma A Complete Guide to Solid Waste Incineration49  Treatment of Solid Waste © Innopharma  Treatment of Solid Waste Solid wastes can be treated or disposed of in a number of ways: © Innopharma  Sludge produced can be treated chemically with coagulant and flocculation aids or polyelectrolytes. This allows dewatering by filtration or centrifugation. The resulting solids are finally disposed of by: o Incineration o Landfill © Innopharma  A facility dedicated to the thermal treatment of waste i.e. burnt under controlled conditions. The wastes entering will determine the conditions for operation. Suitable for non-recyclable waste streams, including flammable solids, liquids and gaseous. Internationally accepted waste management hierarchies rank thermal treatment as being more environmentally desirable than landfill. © Innopharma © Innopharma 54  Incineration reduces waste volume significantly Also, it recovers energy in the form of heat and/or electricity. The energy by-product of incineration can be recovered to power the plant, district heating systems, reducing the need to burn fossil fuels, and consequently reducing GHG emissions. © Innopharma  Most common type of incinerator has an area where the waste is deposited Waste may or may not be segregated (materials may be segregated for recycling) Waste is transported to a combustion chamber (temperatures 850-1100°C) A temperature of which odorous gases and all dioxins will be destroyed From the combustion process a turbine produces electricity and hot water. © Innopharma  After incineration, the remaining residue is called Bottom Ash It is collected at the bottom of the combustion chamber Scrap metal (iron or steel) in the ash is removed using large magnets and sent to steel works for recycling. The remaining bottom ash is non-hazardous and can be recycled for use in other activities e.g. construction of roads. © Innopharma  Fly Ash (1-3% of the original waste volume) is the by-product of the flue gas-cleaning phase. Fly ash is hazardous and needs to be disposed of in a special facility. © Innopharma © Innopharma  Landfill has been the predominant waste practice in Ireland (yet it’s the least preferred option) Licensed by the EPA Limited to non-hazardous materials and treated wastewater treatment plant sludge © Innopharma  It is surrounded by a flexible membrane liner system. The conditions within the landfill are free of oxygen. Non-biodegradable wastes will remain unchanged in the landfill. Biodegradable waste (paper, cardboard, food) will decompose and lead to the production of gases and soluble chemicals. (Methane gas production needs to be monitored as it is a GHG). © Innopharma  Rainwater compressed out of the waste and soluble chemicals will leach out – Leachate. Hazardous because of chemicals within it (incl. metals). Has to be treated to prevent contamination to the soil and water around the landfill site. A landfill liner key to managing leachate. Flexible membrane liner creates seal against escape of the liquid. © Innopharma  Once a landfill stops receiving waste an impermeable cover is used to prevent water entering. Condition of IPC licence – Leachate and gas are managed still until such a time as they don’t pose an environmental risk. Post-closure management period may take many years. Government policy aims to reduce landfill numbers to a smaller network of state of the art facilities. © Innopharma  Treatment of Wastewater © Innopharma  Treatment of Wastewater Created as a result of a process or as a result of a cleaning operation May contain a number of contaminants Condition of the IPC licence is that all waste waters are fully characterized All toxic chemical/contaminants are removed (or recycled and recovered) The wastewater treatment plant removes contaminants from wastewaters to product a final effluent (output) So now safe disposal is possible! © Innopharma © Innopharma 66  Treatment of Wastewater The amount of treatment required depends on the water quality objectives of the receiving water supply. A typical treatment process may involve 3/4 stages: A combination of physical, chemical, and biological processes are used for wastewater treatment process. © Innopharma © Innopharma 68  Before discussing primary, secondary and tertiary processes, lets first discuss the physical and chemical methods of cleaning wastewater © Innopharma  Physical and Chemical Methods (wastewaters) Used to remove hazardous substances from the wastewaters. Part of the 3 stages of wastewater treatment. Substances can be removed from wastewaters by simple physical processes such as: © Innopharma  Physical Processes Sedimentation & Clarification Removal of suspended solids from liquids by gravity settling. © Innopharma  Physical and Process Filtration Involves the passing of wastewater through a filter medium (HEPA filter) which retains the solids and the liquid passes through © Innopharma  Physical and Process Filtration Sand filters used as a final polishing step in treatment of wastewater. This gives very clear effluent. Various types of filters from simple sand filters to rotary drum vacuum filters, belt presses, and filter presses. Filter presses are commonly used to de-water sludge’s This produces a solid waste which may need to be treated before release. © Innopharma  Physical and Process Centrifugation Involves subjecting wastewater to centrifugal force speed. Solids settle to the bottom. This process is often used for dewatering of waste sludge and produces a solid waste called a cake, which is then disposed of by incineration or landfill. Some chemicals (heavy metals) are toxic to humans and the environment & need to be removed from the wastewater before discharge. Also….. e.g. excess phosphates and nitrates result in rapid growth of algae, depletes oxygen, leads to fish kills. Low conc. of O2 is due to excess nutrients (eutrophication). © Innopharma  Physical and Process Centrifugation © Innopharma  Chemical Processes 1. Neutralisation Acid is added to alkaline waste or an alkaline added to an acid waste Result: Neutralise waste (i.e. pH of waste is adjusted to 6.5-8.0 Used as an early step in a waste treatment process Used so bacteria (in later stages of water treatment) stays alive So pH (acid/ alkaline) will not kill the population of bacteria needed to breakdown the organic park of the waste. © Innopharma © Innopharma 77  Chemical Processes 2. Oxidation The addition of strong oxidizing chemicals such as hydrogen peroxide (produces oxygen) Used to chemically breakdown organic wastes. © Innopharma  Chemical Processes 3. Precipitation Addition of specific chemicals to wastewater to cause fine solid materials to join together to form larger solids. Then separate by gravity These settle out of the liquid Chemicals referred to as: o Coagulant aids o Flocculation aids o Polyelectrolytes Choice depends on the nature of the material to be precipitated and the pH © Innopharma  Chemical Processes 4. Absorption Take in or soak up This is the addition of chemicals that absorb toxic organic chemicals Examples: Powdered charcoal absorbs a variety of toxic organic chemicals © Innopharma  Chemical Processes 4. Adsorption Adhesion to a surface to create a film on a surface Wastewater is filtered through an activated carbon filter. Activated carbon: Very effective for removal of dissolved organic chemicals Maximise effectives of the process, activated carbon adsorption is usually performed after secondary treatment. But, activated carbon media becomes exhausted and the filters need to be replaced, then incinerated. © Innopharma © Innopharma 82