CHALLENGES AND OUTLOOK RELATED TO MUNICIPAL SEWAGE SLUDGE MANAGEMENT IN JAPAN

Transcription

1 ISO TC275 Sludge / Biosolids Management Workshop September 8, 2014 : Burlington, Ontario, Canada CHALLENGES AND OUTLOOK RELATED TO MUNICIPAL SEWAGE SLUDGE MANAGEMENT IN JAPAN Jun TSUMORI, P.E.Jp Team Leader of Recycling Research Team, Construction Materials and Resources Research Group, Public Works Research Institute, Tsukuba, Japan

2 OVERVIEW Introduction Background Current Status Challenges Japanese endeavor to enhance sufficient sludge management Promising advanced technologies in Japan Way forward Conclusion 1

3 INTRODUCTION: JAPAN Present Energy Self-sufficiency: 6.0 % Target Under Consideration (2012) (in 20 years) GHG Emissions: % % ( ) ( ) Final Disposal Amount: 19 m t 25m t > (Total of Solid Waste) (2010) (2015) 2

4 STATUS ON MUNICIPAL SEWERAGE IN 2013 Sewered Population: 76.3 % Wastewater Treatment Plants: 2,134 Treated Wastewater: Final Disposal of Sludge: 14 billion c.m 2.2 million DS-t 3

5 Generated Sludge volume(10 3 DS-t) Recycle Rate(%) CURRENT STATUS ON SEWAGE SLUDGE Generated Sludge Volume: 2.2 m DS-t Material Reuse Ratio: 77 % 2,500 2,000 Sewage Sludge Recycle Rate Transition of material use 56 Fuel, etc ,500 1,000 Others Fertilizer Construction material (Excluding Cement) Construction Material (Cement) Land fill Fiscal Year (DS=Dry Solid) Utilization of Digestion gas is not included 4 0

6 Sewage sludge treatment in Japan Final application Dewatering Incineration Purpose Landfill Land fill (as ash) Ash utilization Multi hearth Incinerator (Total over 30 sets were installed ) Now in Japan there is few case of landfill by dewatered sludge. Fluidized bed incinerator (Total 252 sets were installed.) 1974 Advanced fluidized bed incinerator 2009 Melting Slag utilization 1982 After 2011, there is no new construction Carbonization Utilization (fertilizer) Fuel utilization Soil improvement/agricultural utilization Bio- charcoal utilization

7 MOST OF SLUDGE IS INCINERATED IN JAPAN DUE TO LANDFILL LIMITATION Incineration Compost 10.6% 9.7% 5.2% 2.6% 0.1% 0.0% Ash Melting Dewatering Drying Carbonization Others 71.7% Source : Japan Sewage Works Association (2004) 6

8 JAPANESE ENDEAVOR TO ENHANCE SUFFICIENT SLUDGE MANAGEMENT 7

9 BASIC ASPECTS OF ENHANCING SUFFICIENT SLUDGE / BIOSOLIDS MANAGEMENT Enhancing Energy Efficiency, Accelerating exploitation as Renewable Energy, and Advancing development for Cost Reduction of Recycling Technologies 8

10 AMENDMENT TO THE EXISTING POLICY FRAMEWORK Laws and regulations Low Carbon City Law (2012), Sewerage Law (1964), Environmentrelated Laws (1970), Waste Management and Public Cleansing (1970), and related stipulations such as Japanese Industrial Standards (JIS), Technical guidelines by Japan Sewage Works Association Planning, Design, Construction and O&M, and Technical Specifications by Japan Sewage Agency and Major Municipalities Materials, facilities, electricity and buildings etc. Challenges (Cont.) 9

11 NATIONAL DEMONSTRATION PROJECT (B-DASH PROJECT) LAUNCHED IN 2011 Breakthrough by Dynamic Approach in Sewage High Technology Development Theme Adopting Technologies Budget (Million USD) Challenges (Cont.) 10

12 Air preheater Heat exchanger Scrubber Stack <Case Study> Total Optimization for Sludge Incineration 1 Self-controlled dewatering 2 Energy-saving incineration 3 Binary waste heat power generation polymer FeCl3 P P Centrifuge M Thickened sludge Storage tank P Cake Dewatering system control panel MLBI Air Ceramic filter Heat recovery air Incineration system control panel Total control Improvement of three individual processes Optimization of operation by total system control Water chemicals P Heater Evaporator Treated water Turbine Copyright 2008 METAWATER Co., Ltd. All Rights Reserved. G Condenser Power generation system control panel In Ikeda City 11

13 PROMISING ADVANCED TECHNOLOGIES IN JAPAN RELATED TO THE WORKING GROUPS Digestion (Working Group 3) Thermal process (Working Group 5) Thickening and dewatering (Working Group 6) Inorganics & nutrients recovery (Working Group 7) Challenges (Cont.) 12

14 WG3 Digestion Outside-type Digester Mixer Digestion(Methane Fermentation Process) 13

15 Outside-type Digester Mixer (NAS-E) Background Easy installation to existing gas mixing digester Less energy consumption Solution Outside type digester mixer Effect 1/3 energy consumption compared to gas mixing Easy maintenance Reference Location: Ryojima WWTP (Matsumoto city) Circulating flow: 9m 3 /min Horizontal rotational flow Down flow 14

16 Digestion(Methane Fermentation Process) Back Ground Much sludge generate from WWTPs Drastic reduction of cost for sludge treatment is required Solution Steel digester tank with high functionality Low-power impeller agitator Effect 40% reduction of dehydration sludge Create renewable energy Biogas Enable sedimentation level measurement Low-power impeller agitator Reference Nambu-plant(from Dec to Feb. 2013) Higashinada-plant(from April 2012) Copyright KOBELCO METAWATER ECO-SOLUTIONS Co., Co.,Ltd. All rights Rights reserved. reserved. Steel digester tank with high functionality 15 Copyright 2008 METAWATER Co., Ltd. All Rights Reserved.

17 WG5 Thermal process Incineration Advanced Incineration Technology Pressurized Fluidized Bed Incineration Power Generation System with Sewage Sludge Incineration Sludge melting Sludge melting technology Gasification Gasification Technology Carbonization Carbonization Technology Sludge fuel conversion technology 16

18 Advanced Incineration Technology Back Ground Much GHG discharged from WWTPs 24% by N 2 O of incineration process (N 2 O has 310 times as high GHG effect as CO 2 ) Solution Multi-Layer Incineration Technology Partially higher temperature zone Effect 80% reduction of N 2 O (Greenhouse gas reduction) N 2 O from incineration 24% N2O from WWT CH4 from WWT Fuel Solution CO2 amount 6.95 Mil. t/year (2004) Electricity (Pump station) (Source: MLIT) Electricity (WWTP) Zone Control Technology Reference Nambu Sludge Plant #3 (since June 2009) High temp. zone C o m p lete C om b u s t i o n High Temperature Zone Controlled Gasification Copyright METAWATER Co., Ltd. All Rights reserved. Copyright 2008 METAWATER Co., Ltd. All Rights Reserved. 17

19 Pressurized Fluidized Bed Incineration technology Back ground -Compact facility -Power saving -Fuel saving -GHG reduction Sludge feeder Pressurized fluidized bed incinerator Turbo charger Plume prevention air heater Stack Solution Applying Pressurized furnace 1)Pressurized fluidized bed furnace system consist of combination of fluidized bed furnace, which is the most suitable furnace for sewage sludge incineration, and turbo charger. 2)Sewage sludge is combusted under plus pressure (130 to 150kPaG) and pressurized flue gas compressed air for furnace by using turbo charger. 3)Because flue gas is pressurized, flue gas is emitted by its force. Copyright Tsukishima Kikai Co., Ltd. Air pre heater Effect, compared to conventional Fluidized bed As 40% of flue gas volume is reduced, equipments size are also compacted Around 10% of fuel consumption is reduced. 40% of electrical power is reduced. Because of forming high temperature zone, 50% of N 2 O is reduced. Bag filter Plume prevention air fan Scrubber PFBI facility References Tokyo metro.(kasai), 300ton/d, 1 train Tokyo metro. (Miyagi), 300ton/d, 1 train Kanagawa pref., 100ton/d, 1 train Kofu city, 60ton/d, 1 train Osaka pref.,100 ton/d, 1 train 18

20 POWER GENERATION SYSTEM WITH SEWAGE SLUDGE INCINERATION Background Demand for renewable energy Needs for CO 2 reduction Solution Low water content dewatered Low power furnace Steam power generation Effect Power generation: >100kW Supplying surplus power outside Low water content dewatered sludge Advanced centrifugal dehydrator Water content reduction technology Nextgeneration step grate stoker furnace (with wasteheat boiler) Energy recovery technology Heat recovery Steam power generation system Energy transduction technology Project Location: Wakayama Central WWTP Capacity: 35 wet-t/day National high-technology promotion project entrusted by NILIM, Japan (Still from June 2013) Demonstration plant 19

21 Copyright Back ground - NO disposal area for sludge -Sludge utilization as construction material. - Heavy metal leakage problem Solution - Sludge melting - Heavy metal solidification in slag. - Sludge vitrification and utilization Effect - Prevent heavy metal leach out - Utilization of melting slag - Minimize N 2 O (GHG) in emission References -Kyoto Pref., Vortex melting150ton/d, 2trains -Osaka city, Vortex melting 150ton/d, 5trains -Chiba city, Vortex melting 15ton/d, 1train -Hyogo pref., Coke bed melting 180ton/d, 3trains -Osaka pref., Coke bed melting 50 ton/d, 2trains, 75ton/d, 1 train -Osaka pref., Coke bed melting 80ton/d, 1train, 110ton/d, 2trains -Nagano Pref., Ash melting plant 3ton/d, 1train Tsukishima Kikai Co., Ltd. Sludge melting technology Sludge dryer Vortex melting furnace Slag cooler Bag filter Scrubber Stack Flue gas heat recovery Example of Melting plant, Vortex melting Vortex melting facility Melting slag 20

22 Water Gasification Technology (WtE tech.) Background Demand for renewable energy Needs for CO 2 reduction Solution Sludge gasification Fuel gas power generation Sludge cake Rotary drum dryer Green waste High temp. cyclone High Reforming temp. furnace ash Steam O 2 Catalytic reactor Fuel gas Gas engine Scrubber Generator Waste water LNG Power Effect Power generation: 150kW CO 2 reduction: 12,500 t/year Air Gasification furnace Cooling tower Ash Dust collector (in total of WWTP) Project Location: Kiyose WWTP Capacity: 100 wet-t/day Operation: from 2010 for 20 years Copyright METAWATER Co., Ltd. All Rights reserved. Sludge gasification plant Gasification reactor Courtesy of TMG Copyright 2008 METAWATER Co., Ltd. All Rights Reserved. 21

23 Carbonization Technology (WtE tech.) Background Demand for renewable energy Needs for CO 2 reduction Solution Sludge carbonization Bio-charcoal for co-combustion Effect Power generation: 4,600MWh/year CO 2 reduction: 8,000 t/year EPC of facility WWTP Sludge Carbonization Facility (in total of WWTP and Power plant) Reference Location: Kinuura Tobu WWTP METAWATER Purchase Capacity: 100 wet-t/day (Bio-charcoal 8 t/day) Operation: from 2012 for 20 years 60% financing 40% SPC [Scope of business] 1. O&M of facility 2. Bio-charcoal purchase/sale Bio-charcoal Chubu Electric Power Sale Power Plant Co-combustion Copyright METAWATER Co., Ltd. All Rights reserved. Copyright 2008 METAWATER Co., Ltd. All Rights Reserved. 22

24 Sludge fuel conversion technology Back ground Stack -Thermal recycle between Sewage treatment Plant and Power plant. - Keep higher calorie in fuel product. - Reduce odor in fuel product. Hot blast furnace After burner Solutions Heat exchanger Dryer -Applying low temperature carbonization. (250 to 350 carbonization) - Supplying fuel product to power plant as fuel. Scrubber Carbonization furnace Granulator Dewatered sludge Hot blast furnace Effects Fuel product - Promotion of recycling sewage sludge - Reduction of Greenhouse gas in both Sewage treatment plant and Power plant. Sewage Treatment Plant SPC Dewatered sludge Carbonization facility Selling sludge fuel Efficient use Valuable Power Plant Carbonized sludge Renewable energy References Hiroshima City, 50ton day, 2 units Kumamoto City, 50ton day, 1 unit Osaka City, 150ton day, 1 unit Yokohama City, 150ton day, 1 unit Kyoto pref., 50ton day, 1 unit Transportation 23 Copyright Tsukishima Kikai Co., Ltd.

25 WG6 Thickening & Dewatering Thickening Rotary Fin Sludge Collector Dewatering Centrifugal Dewatering machine ISGK Screw Press(Dewatering Machine) 24

26 Rotary Fin Sludge Collector (RFC) Background Poor settleability in gravity thicker much energy consumption of mechanical thickening Double cylindrical plates Raw sludge Motor Center Well Rotary fin Scam skimmer Supernatant Solution Sludge collector with rotary fin Thickened sludge Effect 10 20% higher concentration of thickened sludge (Certified by JIWET*) Reference Tank diameter: φ7.0m 17.0m Units: 14 units Installation in gravity thicker *JIWET: Japan Institute of Wastewater Engineering and Technology 25

27 Centrifugal Dewatering Machine (SDR Impact) Background Cost reduction of sludge disposal Needs for CO 2 reduction Solution Inject inorganic coagulant sludge directly to the dry beach area polymer sludge dry beach in26organic chemical polymer supernatant Effect 7 10 point lower water content (68 75% water content) (Joint research with JS*) Reference Capacity: 5 40 m 3 /h Units: 36 units *JS: Japan Sewage Works Agency 68% water content of mixed sludge 26

28 ISGK Screw Press (Dewatering Machine) Background Needs for energy saving Needs for easy overhaul Solution Metal filter Simple structure Sewage Primary Settling Tank Thickening Tank Digestion Reactor Mechanical Thickening Anaerobic Digested Sludge Final Settling Tank Excess Sludge Treated Water Screw Press Cake Effect Low water consumption Low electric power consumption Overhaul cost reduction Comparison with Other Dewatering m3/day Reference Approx. 300 units in Japan Approx. 70 units outside of Japan High Efiiciency Belt Press High Efficiency Centrifuge ISGK Screw Press Water Electric Power Replace parts 27

29 WG7 Inorganics & nutrients recovery Phosphorus Recovery Phosphorus Recovery from Incineration Ash Phosnix Phosphorus Recovery as struvite Phosphorus Recovery as HAP from Black Water 28

30 Phosphorus Recovery from Incinerated Ash Others Background Phosphorus ore P 2 O 5 CaO Lack and price increase of natural phosphorus ore High P ratio in incinerated ash Incineration Ash No difference in P ratio 20~ 30% less Ca SiO 2 Al 2 O 3 Fe 2 O 3 Other oxides Heavy metals Solution Alkaline Dissolution Technology Regeneration of P and neutralized ash Effect Recycled P: Raw material of fertilizer (certified by MAFF * ) Neutralized Ash: suitable for cement Incinerated Ash Recycled Phosphorus Neutralized Ash Capacity : 5 tons/d (Gifu pref.) Reference 5 wet-ton/day plant (Gifu prefecture) (Operation started in 2010) * MAFF : Ministry of Agriculture, Forestry, and Fisheries Copyright METAWATER Co., Ltd. All Rights reserved. Copyright 2008 METAWATER Co., Ltd. All Rights Reserved. 29

31 Phosnix Phosphorus Recovery as Struvite Background Drying up high-grade P resources Clogging trouble in sludge treatment facilities in SWTP Solution Application of Struvite recovery system in SWTP Recovered Struvite Effect Recovery of fertilizer grade Struvite (certified by MAFF) Prevention of Scaling trouble Reduction of Phosphorus discharge Reference Shinjiko Tobu SWTP(500m 3 /day 2) ( Since 1998 ) Ono SWTP(300m 3 /day) Copyright Hitachi Zosen Corporation. All Rights reserved. 30 Shinjiko Tobu Project Copyright 2008 METAWATER Co., Ltd. All Rights Reserved.

32 Phosphorus Recovery as HAP from Black Water Background Drying up high-grade P resources Solution Application of HAP recovery system Recovered HAP Effect Recovery of fertilizer grade HAP (certified by MAFF) Reduction of surplus sludge Project Senboku City (60m 3 /day) Kushimoto Town (45m 3 /day) and 3 projects Senboku City Project 31 Copyright Hitachi Zosen Corporation. All Rights reserved. Copyright 2008 METAWATER Co., Ltd. All Rights Reserved.

33 WAY FORWARD IN JAPANESE WASTEWATER TREATMENT PLANTS Evolving into urban centers as energy supply and material recycling hubs. 32

34 URBAN ENERGY AND MATERIAL RECYCLING HUB (Wastewater heat utilization by deregulation) Electric Power Provider Electricity Heat Supply Facilities Heat (Hot-Water Supply, Cooling and Heating) Power Plant Incineration heat wastewater heat Energy Supply Hub Solid Fuel Production Bio solid fuel production (R&D by B-DASH Project) Sewage Heat Sewage Scrap Wood Office Building City Gas CNG Car Fuel Household Food Waste Wastewater Treatment Plant Methane Fermentation Facility Biogas Material Recycling Hub Farm Sludge City Gas Plant Biogas Station 33

35 CONCLUSION Energy security and global warming as well as Natural resource conservation are crucial issues to share the earth. Sludge Treatment Plants are responsible for saving energy and reducing Green House Gas emissions, and have great potential as distributed urban energy and material recycling hubs. To boost performance of each sludge treatment process in terms of energy sufficiency and GHG reduction must be considered in ISO/TC275 discussion to contribute our future. 34

36 THANK YOU FOR YOUR KIND ATTENTION! For contact: 35