CHL7240 Advanced Wastewater Treatment PDF

CHL7240 Advanced Wastewater Treatment Faculty: Prof Pradip K Tewari and Dr Vikky Anand (TAs: Hemant; Etisha; Himanshu) Course Content Title Advanced Wastewater Treatment Number CHL7240 Department Chemical Engineering L-T-P (C) 3-0-2 (4) Waste water engineering: an overview, charac...

CHL7240 Advanced Wastewater Treatment Faculty: Prof Pradip K Tewari and Dr Vikky Anand (TAs: Hemant; Etisha; Himanshu) Course Content Title Advanced Wastewater Treatment Number CHL7240 Department Chemical Engineering L-T-P (C) 3-0-2 (4) Waste water engineering: an overview, characterisation of wastewater and monitoring of industrial and municipal wastewater, emerging contaminants, environmental impacts of wastewater constituents. (4 lectures) Conventional Water/ Wastewater Treatment: Existing unit operations and processes, basic philosophy of water and wastewater treatment plants; physio-chemical treatment methods: (i) Screening, (ii) conventional filtration (iii) coagulation, (iv) flocculation, (v) floatation (vi) Clari-flocculation (vii) sedimentation, (viii) sand filtration, etc. (10 lectures) Aerobic and Anaerobic Suspended and Attached Growth Wastewater Treatment Processes: Aerated lagoon, activated sludge systems, trickling filter, sequential batch reactor, fluidized bed bioreactors, Upflow Anaerobic Sludge Blanket (UASB) and hybrid Up-flow Anaerobic Sludge Blanket (UASB) reactors. (8 lectures) Advanced Treatment Processes: Membrane Filtration, microfiltration, ultrafiltration, nanofiltration, reverse osmosis and electrodialysis; wet air oxidation, adsorption and ion- exchange; wet-land and rootzone treatment of industrial and municipal wastes; design of sludge drying beds, thermal and biological processes for sludge and land fillings. membrane reactors, new technologies for wastewater disinfection. (12 lectures) Water Recycling and Reuse: Different unit operations for water recycling depending on end use, energy considerations, recovery of valuables from wastewater, zero liquid discharge (ZLD). (8 lectures) Waste Water Treatment Design Lab (28 hrs) Water Quality Analysis (TDS, pH, Turbidity, BOD, COD etc) Design of Conventional Systems (LSI, Screen, Grit Chamber, Clarifier, PSF etc) Field Visits (Water Treatment Plant, Decentralised Wastewater Treatment System) Advanced System Design Mini-Project Text Book 1. Burton F.L., Tchobanoglous G., Stensel H.D., 2017, Waste Water Engineering Treatment and Reuse, 4thed.,Tata McGraw-Hill. 2. 2. Arceivala S.J. and Asolekar S.R., 2007, Wastewater Treatment for Pollution Control and Reuse, 3rd Ed., Tata McGraw Hill. Reference Books 1. Henze M., van-Loosdrecht M.C.M., Ekama G.A. and Brdjanovic D., 2008, Biological Wastewater Treatment: Principles, Modelling and Design, IWA publishing. 2. Sincero A.P. and Sincero G.A., 1996, Environmental Engineering – A Design Approach, Prentice-Hall. 3. Tewari P.K., Online Course Material 1. Tiwari M K, Wastewater treatment and recycling, NPTEL Evaluation Criteria i. Main Exam: 40 Marks ii. Minor Exam: 20 Marks iii. Assignments: 10 Marks iv. Quiz: 10 Marks v. Mini Project (Project Report+Presentation): 20 Marks vi. Total Marks (i+ii+iii+iv+v): 100  Mini Project Guidelines Mini Project: Advanced Wastewater Treatment Plant Design Problem Statement (Submission Date: 20/01/2025); Phase I: Primary Treatment (Submission date: 15/02/2025); Phase 2: Primary+ Secondary Treatment (Submission date: 15/03/2025); Phase 3 (a): Overall Advanced Wastewater Treatment Plant Design with Recommendations (Submission date: 05/04/2025) Phase 3 (b): Presentations during March end and Beginning of April 2025 Mini Project Guidelines Problem Statement/ Mini Project Report STP in respective municipal areas/ Water Treatment Plant in respective areas/ Greywater Treatment in urban areas; residential areas/ Pond water Treatment/ Industrial Effluent Treatment (Textile or Paper or Tanneries or Food or Steel or Power Plant or Microelectronics etc.)/ SBM (Swachch Bharat Mission) related issue and probable solution/ Greywater Treatment in rural areas / Water Treatment for High-End Industries etc. (Not limited to above) Tentative Capacity, Inlet Quality Outlet Quality required Conventional Treatment Methodology Currently Followed Proposed Plan of Work Example for reference: Typical Conventional Sewage Treatment Plant  Samudra Manthan: IIT Jodhpur Concept of Innovative Wastewater Management (3Rs: Reduce, Reuse, Recycle) Amrit (Good Water as Product for Stakeholders Recycle & Reuse) coming together Seawater (Wastewater) Ratnas (Recovery of Valuables from Wastewater) Energy applied (No/ Reduced Carbon Foot Print) Poison (Concentrate) 1/9/2025 8 Introduction What is wastewater? i. Used-water in home, business premises or industrial premises. ii. Used-water in washing, flushing or manufacturing. Wastewater: a burden or resource? i. It contains pollutants. ii. More than 99% is water. What is wastewater treatment? i. Processing of wastewater for removal of contaminants. What is wastewater recycling? i. Wastewater treatment for reuse in a beneficial manner. ii. Engineering Challenges: Techno-economics, Sustainability, Acceptability. Terminologies commonly used in Wastewater Treatment Biosolids: Primarily an organic semisolid wastewater product and are suitable for beneficial use. Class A Biosolids: Pathogens reduced below detectable levels. Class B Biosolids: Pathogens reduced to levels that are unlikely to pose threat to public health and environment under specific use conditions. Constituents: Individual components, elements or biological entities Contaminants: Constituents added to water supply through use Disinfection: Reduction of disease-causing micro-organisms Effluent: Liquid discharged from a processing step Terminologies commonly used in Wastewater Treatment Nonpoint sources: Sources of pollution that originate from multiple sources Pollutants: Constituents added to water supply through use Reclamation: Treatment of wastewater for subsequent reuse Recycling: Reuse of treated wastewater for beneficial purposes Sludge: Solids removed from wastewater during treatment. Solids that are treated further are biosolids. Wastewater Source and Types Wastewater Domestic, School, Hotel Agricultural Industrial Washing Industrial Shower Sewage effluent Kitchen Wastewater Wastewater Colour coding: Green water: Agriculture-runoff water Grey water: Shower, Kitchen water Black water: Sewage water Light blue water: Potable water Pollutants in Wastewater Pollutants have harmful health-effects. Pollutants: Natural or anthropogenic. Contaminants may not have harmful health-effects  Point source pollution and nonpoint source pollution Point source pollution Nonpoint source pollution (Dispersed or distributed source) What is it? Source is known and Source is not known such as can be monitored such agricultural lands run-off as pipeline, well etc. (containing pesticides and other undesirable constituents). Also called as dispersed or distributed source. Where does come from? Sewage treatment Run-off water (Contains excess plant, industrial pesticides, fertilizers), Wastewater effluents from Construction sites (Contains Micro-organisms such as bacteria, virus in water). Point source pollution and nonpoint source pollution (contd.) Point source pollution Nonpoint source pollution (Dispersed or distributed source) Difference Discharge may be Dispersed and distributed controlled by the permits/ source from many regulations. locations. Difficult to enforce regulations. Easy to control because Individual contributions location and type of may be small but overall contaminants are known cumulative impact may be significant Easy to monitor, evaluate Difficult to monitor. and plan Requires many stations.  Need of Wastewater Management Discharge of untreated wastewater leads to environmental pollution and harmful impact on living-beings: Adverse impact on human health, water-borne diseases such as Cholera, Diarrhoea, Typhoid etc. Negative impact on environment, such as wastewater pollutes the receiving water body e.g. river etc. Potential impact on economic activities: Adverse economic impact on down-stream/ receiving side, such as additional treatment; loss of agricultural output, contamination of agricultural produce, loss of fisheries/ aquaculture, impact on industrial production, Adverse impact on health due to water borne diseases leading to extra expenditure, loss of man-days etc. Indian Standards for Tolerance Limits for Industrial Effluents The following Indian Standards lay down tolerance limits for industrial effluents : IS : 2490 -1974Tolerance limits for industrial effluents discharged into inland surface waters : Part I General IS : 3306-1974Tolerance limits for industrial effluents discharged into public sewers IS : 3307-1977Tolerance limits for industrial effluents discharged on land for irrigation purposes IS : 7968-1976 Tolerance limits for industrial effluents discharged into marine coastal areas. Need of Advanced Wastewater Treatment Recycling of wastewater is a sustainable approach for wastewater management. Recycling need quality of water to be fit for the designated or intended use. So, quality of wastewater needs to be improved by appropriate treatment. Advanced wastewater treatment is a critical step in wastewater management, as suitability of wastewater for recycling or disposal, depends on the ability of the treatment steps to reduce to the desired level or eliminate the contaminants from the wastewater.  Wastewater Management: Recycling Perspective Health protection Technical system options Resource management options Resources in wastewater Water Water recycling Centralised/ Nutrients and reuse Decentralised Environment Energy Water and options protection content nutrient reuse Grey water Organic Energy management matter generation Sludge Water Security Other Ecosystem management services, such Offsite vs. Food security as constructed onsite wetlands treatment Other outputs Energy security e.g. construction or building materials Wastewater Management: Global Scenario (UNESCO Data 2017) S. Classification Untreated Untreated No. Wastewater % Wastewater in 2015 Target % by 2030 1 High income countries 30 15 2 Upper-middle income 62 31 countries 3 Lower-middle income 72 36 countries 4 Low income countries 92 46 THERE ARE PEOPLE IN THE SOCIETY FOR WHOM CIRCUMSTANCES, LACK OF RESOURCES AND SETBACKS ARE NO HURDLES. THESE INDIVIDUALS ARE PEOPLE OF WILL AND DEDICATION. THESE INDIVIDUALS POLISH THEIR LIVES SO MUCH IN THEIR FIELD OF INTEREST THAT THEY STAND APART IN SOCIETY. नमस्ते Thanks  Advanced Wastewater Treatment (Wastewater Generation & Quantity Estimation) Pradip K Tewari Wastewater Generation & Quantity Estimation Different sources of wastewater (Municipal, agricultural and industrial), producing different qualities of wastewater The characteristics of wastewater differs based on source. Industrial effluents are considered as most polluted type of wastewater. The un-sustainable management of wastewater in urban and rural areas presents a major challenge. Quantitative Estimation of Wastewater Wastewater generated from industry depends on type of industry, production capacity and process followed. Estimation of agricultural run-off depends on type of crop, crop pattern, irrigation supplies and precipitation. Municipal wastewater quantity estimation is typically done based on number of habitants and water use practices. Standard guidelines (Central Public Health and Environmental Engineering Organisation (CPHEEO)) are followed for estimating sewage water quantity. Need for Quantitative Estimation Quantitative estimation is required for designing the system. Overestimation of quantity may lead to uneconomical system. Under-estimation may lead to inadequate design. Quantitative Estimation of Sewage Design period of sewers include future years. Quantitative estimation for sewer discharge includes forecasted population till design period. Dry weather flow (the actual flow of sanitary sewage) Dry weather flow depends on quantity of water used, type of area served, weather conditions, infiltration in the sewers, if any. Since there is fluctuation in the pattern of water consumption, there will be fluctuation in dry weather flow too. Quantity Estimation of Sewage: Input components Water discharged from house-holds Industrial effluents (if any, from some of the small scale or cottage industries) Used water discharged from the public places such as schools, colleges, hotels, theatres, commercial complexes. Private water supplies (water drawn from borewells, lakes, rivers by individual/ industries) to fulfil water demand, if discharged to sewers Entry of rainwater/ ground water into sewers Quantity Estimation of Sewage: Steps Fix the design period: Based on useful life of structures and equipment used Estimate design population: Using standard population forecasting methods Estimate per capita sewage generation: Based on recommended water use and wastewater generation pattern Estimation of peak flow: consider fluctuations Accounting for additional flows, if any: from sources other than domestic sewage Estimation cumulative design flow Quantity Estimation of Sewage Central Public Health and Environmental Engineering Organisation (CPHEEO) recommended design period of sewerage components S. No. Component Design Period (Years from base year) 1 Land 30 2 Pumping mains 15 3 Pumping station civil works 30 4 Pumping machinery 15 5 Sewage treatment plant 15 Quantity Estimation of Sewage Estimation of Design Population Factors affecting population Birth rate Death rate Migration Annexation Population forecasting methods Arithmetic increase method Assumption: Population increases at constant rate dP/dt is average increase in population per unit time which is arithmetic mean constant (k) or Pt=P0+kt i.e. k= ((dP1/dt)+ (dP2/dt)+ (dP3/dt)+ (dP4/dt)+--- (dPn/dt))/n It gives lower population estimate. Geometric increase method Assumption: %age growth rate is constant Pt=P0(1+(r) t) i.e. r= ((dP1/dt)x (dP2/dt)x (dP3/dt)x-------x (dPn/dt))(1/n) where r is geometric mean constant. Per Capita Sewage Generation Entire spent water of community should normally be equal to total flow in a sanitary sewer. However, it is less in dry weather conditions due to evaporation, seepage to underground, leakage. Conventional sewers are designed for minimum sewage flow of 100 Litres per capita per day or higher as the case be. Estimation of Peak Flow The flow in sewer varies hour to hour and also on seasonal basis Thumb Rule Maximum daily flow= 2xAverage annual daily flow Maximum hourly flow=1.5xMaximum daily flow on hourly basis = 3xAverage annual daily flow on hourly basis Minimum flow may vary from 33% to 50% of average flow. Accounting Additional Flows and Outflows Inflow due to Infiltration: Infiltration through the joints; Difficult to estimate CPHEEO (2012) recommends infiltration inflow should be limited to 10% of design value of sewage flow. Inflow from commercial establishments such as commercial buildings, hotels, lodges, airport etc using water from other than municipal supply. CPHEEO (2012) gives institutional need for potable water consumption. Inflow from unaccounted private water supplies such as tube wells, private boring etc Inflow from industries using private water sources and discharging into public sewer So, design flow is algebraic sum of the above, which is used for designing the system.  CHL7240 Advanced Wastewater Treatment Pradip K Tewari Wastewater Characteristics: Quality Parameters pH (6.5-8 in general; may have 4.5-10 in certain cases; Extreme pH affects aquatic ecology) Temperature (Living organism can tolerate only a certain temperature range) Colour (Often caused by organic contaminants) Turbidity (Presence of fine suspended particles) Conductivity (Presence of ions in water) Dissolved Oxygen (DO) (If DO0 implies water is supersaturated wrt CaCO3, scaling may take place. LSI0 implies water is supersaturated wrt CaCO3, scaling may take place. LSI