Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction TNPL

Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction : TNPL Case Study Dr. S.CHINNARAJ Dr S CHINNARAJ Research and Development Division Tamilnadu Newsprint and Papers Ltd Kagithapuram, Karur TN- 639 136 TNbiotech@tnpl.co.in International Training Course on Bio-Energy BioMarch 19 – 31, 2006 31 Indian Institute of Science, Bangalore (Sponsored by MNES, Government of India) Tamilnadu Newsprint and Papers Ltd. Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction : TNPL Case Study 1. About TNPL g 2. Anaerobic Digestion 3. Greenhouse Effect and Climate Change 4. 4 Biomethanation & Climate Change 5. Biomethanation In TNPL Tamilnadu Newsprint and Papers Ltd. Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction : TNPL Case Study 1. About TNPL Tamilnadu Newsprint and Papers Ltd. About TNPL • • • • • • Promoted by the Govt. of Tamil Nadu during early eighties to manufacture Newsprint & fine paper using bagasse as primary raw material The largest bagasse based paper mill in the World. Consumes one million MT of bagasse every year Commenced the commercial production with a capacity of 90,000 tpa in 1985 Increased the capacity to 1,80,000 tpa in 1996 by installing the second paper machine. hi Capacity increased to 2,30,000 tpa in 2002 through upgrade of paper machines As continual improvement, TNPL embarked on a Mill development plan at improvement a cost of Rs.565 Crores to become environmentally benign by implementing Elemental Chlroine Free (ECF) bleaching sequence in the inhouse pulping lines Tamilnadu Newsprint and Papers Ltd. TAMIL NADU NEWSPRINT AND PAPERS LIMITED Kagithapuram, Tamil Nadu Tamilnadu Newsprint and Papers Ltd. Tamilnadu Newsprint and Papers Ltd. Tamilnadu Newsprint and Papers Ltd. Tamilnadu Newsprint and Papers Ltd. Tamilnadu Newsprint and Papers Ltd. Tamilnadu Newsprint and Papers Ltd. Tamilnadu Newsprint and Papers Ltd. Tamilnadu Newsprint and Papers Ltd. Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction : TNPL Case Study 2. Anaerobic Digestion Tamilnadu Newsprint and Papers Ltd. Why Anaerobic Digestion ! Biodegradable pollutants in the wastewater are converted to biogas containing methane carbon dioxide and methane, biomass (little) in the absence of oxygen by Anaerobic microorganisms 5% 10% Biomass Effluent Organic Pollutants Anaerobic Microbes CH4, CO2 H2S + New Cells Net energy surplus is generated during AD in the form of CH4 bearing biogas 85% CH4/CO2 Tamilnadu Newsprint and Papers Ltd. Metabolic Stages of Anaerobic Digestion Polymers (Proteins, Polysaccharides) 1 Monomers (Sugars, Amino acids, Peptides) 2 2 Propionate, Butyrate H2 + CO2 4 3 3 3 Acetate A t t 4 2 1. Hydrolytic Bacteria 2. Fermentative Bacteria 3. Acetogenic Bacteria 4. Methanogenic Bacteria CH4 + CO2 Tamilnadu Newsprint and Papers Ltd. Types of Anaerobic Reactors Low rate anaerobic reactors High rate anaerobic reactors Anaerobic contact process Anaerobic Lagoon Septic tank Standard rate anaerobic digester Slurry type bioreactor, temperature, mixing, SRT or other environmental conditions are not regulated. . loading of 1-2 kg COD/m3-day. Anaerobic filter (AF) Upflow anaerobic sludge Blanket (UASB) Fluidized bed Reactor Hybrid reactor: UASB/AF Able to retain very high concentration of active biomass in the reactor. Thus extremely high SRT could be maintained irrespective of HRT. Load 5-20 kg COD/m3-d HRT 5 20 d COD removal efficiency : 80-90%. Tamilnadu Newsprint and Papers Ltd. Upflow Anaerobic Sludge Blanket (UASB) UASB was developed in 1970s by Dr. G. Lettinga in the N th l d th Netherlands It is a special kind of reactor concept for high rate anaerobic treatment of wastewater t bi t t t f t t It is essentially a suspended growth system in which proper hydraulic and organic loading rate hi h h d li d i l di is maintained in order to facilitate the formation of granules The granules consist of hydrolytic bacteria, acidogen/acetogens and methanogens id / d h Tamilnadu Newsprint and Papers Ltd. UASB REACTOR Biogas Settler Baffle Weir for effluent collection Rising gas bubble Sludge bed Influent Influent distributor Tamilnadu Newsprint and Papers Ltd. Essential Conditions for Anaerobic Treatment 1. No excessive air/O2 exposure, pH (6.8 - 7.8), Temp. Temp 30 to 38oC, Alkalinity >1500 ppm C 2. No toxic/inhibitory compounds in the influent 3. Enough nutrients (COD:N:P = 500:7:1) and trace metals especially, Fe, Co, Ni, etc. t t l i ll F C Ni t Tamilnadu Newsprint and Papers Ltd. Best Candidates of Industrial Wastewater for Anaerobic Treatment • • • Alcohol production & Brewery Sugar processing Starch (barley, corn, potato, wheat, tapioca) and desizing waste from textile industry industry. Food processing & Slaughter house Pulp and paper p p p Petrochemical waste Tamilnadu Newsprint and Papers Ltd. • • • Process Advantage 1. Less energy requirement, because no aeration is needed e gy generation the o of et a e 2. Energy ge e at o in t e form o methane gas 3. Less biomass (sludge) generation ( ) q 4. Less nutrients (N & P) requirement because of low biomass 5. Higher organic loading rate 6. Space saving due to high organic loading Tamilnadu Newsprint and Papers Ltd. Limitations of Anaerobic Process 1. Long start-up time due to low biomass yield start2. Long recovery time due to low biomass y g y yield 3. Specific nutrients/trace metal requirements 4. 4 More susceptible to pH temperature and pH, redox potential 5. Quality of treated wastewater Tamilnadu Newsprint and Papers Ltd. Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction : TNPL Case Study 3. Greenhouse Effect and Climate Change Tamilnadu Newsprint and Papers Ltd. Greenhouse Effect Greenhouse gases keep IR from transmitting directly out to space Tamilnadu Newsprint and Papers Ltd. GHG in Atmosphere GHG Name Carbon –di- Oxide diMethane Nirous Oxide CFCCFC-12 HCFCHCFC-22 Perfluromethane PrePre-industrial Concentrat life time GWP Concentration i in 1994 ( C t ti ion i (years) ) 278 ppmv 700 ppbv 275 ppbv 0 0 0 377 ppmv 1783 ppbv 318 ppbv Variable 1 12.2 120 21 310 6200-7100 62001300-1400 13006500 23900 0.503 ppbv 102 0.105 ppbv 12.1 0.070 ppbv 50000 0.032 ppbv 3200 0 032 Sulphur hexa-fluride 0 hexa- Tamilnadu Newsprint and Papers Ltd. CO2 in Atmosphere Tamilnadu Newsprint and Papers Ltd. GHG and Global Warming Tamilnadu Newsprint and Papers Ltd. Atmosphere is warming ? Tamilnadu Newsprint and Papers Ltd. Impacts Tamilnadu Newsprint and Papers Ltd. International Efforts United Nations Framework Convention on Climate Change (UNFCCC) • • • Ultimate objective of stabilizing global greenhouse gas concentrations in the atmosphere Developed countries (Annex I countries) aim to restore GHG emissions to 1990 levels and less Support capacity building in, and facilitate technology transfer to developing countries to mitigate, and to adapt to climate change Tamilnadu Newsprint and Papers Ltd. Polluter Should Pay Annex I Non-Annex N A Tamilnadu Newsprint and Papers Ltd. Promises Made Kyoto Protocol: 36 Developed Countries and Economies in Transition (namely Canada Japan European Union and most Canada, Japan, East European countries) agree to: • • • • • Reduce GHG emissions by 5.2 % below 1990 levels in the y commitment period 2008-2012 2008Marrakech Accord: agreed in Nov 2001 sets rules of implementation Required ratification of 55 Parties to UNFCCC representing 55 % of CO2 emissions from developed countries Came into force February 16, 2005 As of February 2006, 162 states ratified representing 66.1% developed countries emission Tamilnadu Newsprint and Papers Ltd. Solutions ! How can Developed Countries/EITs meet their obligations under Kyoto? • Domestic Emission Reductions a d o est y activities ( and forestry act t es (limited to ~330 Mt/CO2e) ted 330 t/CO • Carbon Sinks: Direct human-induced land use change human• International Emissions Trading • Project Based: Joint Implementation j p Clean Development Mechanism Tamilnadu Newsprint and Papers Ltd. Market Based Mechanism ! Trade of Emission Allowances Carbon Transactions Joint J i t Implementation (JI) ProjectProject-Based Transactions Clean Development Mechanisms (CDM) NonNon-Kyoto Projects Tamilnadu Newsprint and Papers Ltd. Type of Projects 1. Installations b 1 I t ll ti based on renewable energy (Geo thermal, wind, d bl (G th l i d solar, biomass, small hydro etc.) 2. Fuel switch to lower carbon intensive fuels (electricity, heat sector) 3. Combined heat and power projects 4. Transport sector 5. Land fills gas recovery (methane emission avoidance & use) 6. Waste & Wastewater handling (methane emission avoidance and use) se) 7. Reforestation and Afforestation (A/R) projects (carbon sequestration). Tamilnadu Newsprint and Papers Ltd. Project Cycle • • • • • • Project Design Validation / Registration Monitoring g Verification / Certification CER Issuance Project Participant (PP) Designated Operating Entity (DOE) Executive Board Project Participant (PP) j p ( ) Designated Operating Entity (DOE) Executive Board (EB) Tamilnadu Newsprint and Papers Ltd. Registered Projects by Country y Tamilnadu Newsprint and Papers Ltd. CERs from Registered Projects by Country Tamilnadu Newsprint and Papers Ltd. Registered Projects by Sector Tamilnadu Newsprint and Papers Ltd. Energy distrib b. Transport Tidal EE Service N2O EE Households CDM Projects in Pipeline G eothermal Solar Fugitive HFCs Cement Biogas Fossil fuel sw witch Landfill gas Agriculture Wind EE Industry Hydro Biomass ene rgy Tamilnadu Newsprint and Papers Ltd. 80 60 40 140 120 100 20 0 Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction : TNPL Case Study 4. Biomethanation & Climate Change Tamilnadu Newsprint and Papers Ltd. Methane and Climate Change Methane: Most abundant greenhouse gas after CO2 in the atmosphere Concentrations is increasing from pre -industrial times (now :1783 ppbv) 23 times more Global warming potential than CO2 Contribution to Global Warming HaloHalo-carbons 18% N2O 6% CH4 19% CO2 57% Tamilnadu Newsprint and Papers Ltd. Methane in Atmosphere GHG Increase From 1750 CO2 :35% CH4 :155% N2O :18% Tamilnadu Newsprint and Papers Ltd. Anaerobic Treatment for Emission or Energy ? gy Conventional Uncontrolled Anaerobic Digestion Controlled Anaerobic Digestion (UASB) Reduced CO2 Emission 85% CH4 /CO2 Emission Reduced Fuel use No CH4 Emission Power Plant, Lime kiln Anaerobic Reactor (5% Bi Biomass) ) Organics in wastewater Anaerobic Lagoon (Biomass 5%) 10 % in effluent Organics in Wastewater 10 % in Effluent Tamilnadu Newsprint and Papers Ltd. Anaerobic Wastewater Treatment for Energy Recovery and Emission Reduction : TNPL Case Study 5. Biomethanation In TNPL Tamilnadu Newsprint and Papers Ltd. TNPL ETP Process Flow g Diagram Bagasse Handling and Preparation Screens Bag. ag Clarifier Anaerobic UASB Lagoon process Primary Clarifier 2 Pulp-mill PM/c & Others Screens Primary Clarifier I Activated Sludge Lagoon L Sec. Clarifier SLUDGE FOR DISPOSAL SLUDGE DEWATERING Sludge Thickener TO IRRIGATION Tamilnadu Newsprint and Papers Ltd. TNPL Biogas Process Flow Diagram g Lime-Kiln Gas Holder UASB Reactor A UASB Reactor B MOL Tank Bag. Wash Wastewater Equal. Tank Neutral. Tank Clarifier Buffer Tank Nut. Tank Sludge for Disposal Decanter Centrifuge Sludge Pit Treated Effluent To ASL Tamilnadu Newsprint and Papers Ltd. Biogas Plant Design COD Load Hydraulic Retention Time Reactor Volume Volumetric Loading Rate COD Reduction Gas Production Factor Gas Production Flow : 57.6 T/Day : 20 hrs : 2 X 5,000 m3 : 6.0 kg COD/m3/Day : 85% : 0.47 m3/kgCODr y : 23,000 m3/Day : 12,000 m3/Day Tamilnadu Newsprint and Papers Ltd. Biogas Plant Performance Wastewater Ttreated in m 4,000,000 1 1416150 0 29 947476 3 2,000,000 - 2003 2004 2005 Tamilnadu Newsprint and Papers Ltd. 3 146900 Biogas Plant Performance COD Reduced in MT 11106 6 15000 10000 5000 0 4716 8 8686 2003 2004 2005 Tamilnadu Newsprint and Papers Ltd. Biogas Plant Performance Biogas Produced in m 6,000,000 4,000,000 2,000,000 2 000 000 2 2,374,64 42 3,507 7,891 3 2003 2004 2005 Tamilnadu Newsprint and Papers Ltd. 4, 752,592 2 Biogas Plant Performance Oil Saving in kL S i i 2009 3000 2000 1000 0 1450 2849 2003 2004 2005 Tamilnadu Newsprint and Papers Ltd. CDM Project Status Methane Extraction and Fuel Conservation Project ( g j (High rate Bio-Methanation) Bio• Estimated CERs Generation 37 000 t CO2e y -1 37,000 Project Identification Project Design Document (PDD) Host Country approval (2nd May 2005) Validation Registration (14th January 2006) Verification CER t di trading Tamilnadu Newsprint and Papers Ltd. Emission Calculation Methodology Adopted : Emission Reductions t CO2e AM0013 / Version 02 Project Emissions t CO2e Baseline Emissions t CO2e Tamilnadu Newsprint and Papers Ltd. Baseline Emissions 1. CH4 emission from open anaerobic lagoons Total COD to lagoon Maximum CH4 producing capacity CH4 conversion factor 2. Emission from Fossil fuel combustion Mass conversion factor Biogas used Energy Content of biogas Carbon Content of Fuel Tamilnadu Newsprint and Papers Ltd. Baseline Emission t CO2e 18 54,21 2005 40,000 18,2 289 30,000 20,000 10,000 2003 2,925 22 33,46 68 50,000 40 ,469 4 44,791 60,000 4 4,636 2004 Open Lagoon Fossil Fuel 7,001 Total Tamilnadu Newsprint and Papers Ltd. 9,427 Project Emissions 1. CH4 emission from open anaerobic lagoons Total undigested COD to lagoon Maximum CH4 producing capacity CH4 conversion factor 2. Emission due to leakage Physical leakage from digester g Emission from electricity consumption Tamilnadu Newsprint and Papers Ltd. Project Emission t CO2e 20,000 10890 15,000 , 10,000 2 ,9 4 2 8 ,6 4 6 5959 5 ,1 9 9 5,000 - 2743 5020 2003 274 2004 671 Open Lagoon O L Electricity C El t i it Consump Physical L k Ph i l Leakage 750 2005 6719 16115 Total T t l Tamilnadu Newsprint and Papers Ltd. Emission Reduction t CO2e 60,000 40, ,469 54,218 65 16,96 20,000 10,000 - 2003 5 5,959 2004 10,890 2005 Baseline B li Project P j t Emission R d ti E i i Reduction Tamilnadu Newsprint and Papers Ltd. 16,11 15 30,000 22 2,925 29,579 40,000 38,1 103 50,000 CER Generated from Aug. 2003 – Dec. 2005 100,000 80,000 80 000 29,5 579 60,000 40,000 20,000 16,965 5 38 8,103 2003 2004 2005 Total Tamilnadu Newsprint and Papers Ltd. 84,648 Conclusion The plant generates around 13,000 to 15,000 M3 of biogas with COD reduction of around 83 - 85 % I. Environmental Benefits from Aug. 03 to Dec. 05 • • • • • COD Reduced GHG Reduced Biogas generated Furnace oil Saving CERs CER generated t d :24,500 t :85,000 t CO2e :85 000 :10.64 :10 64 million m3 : 6308 t :85,000 85 000 II. Economical Benefits from Aug. 03 to Dec. 05 Tamilnadu Newsprint and Papers Ltd. Thank You for Your Attention Any Questions ? Tamilnadu Newsprint and Papers Ltd.