次世代火力発電と CO 2 削減 宝田恭之 群馬大学大学院理工学府環境創生部門

Transcription

1 次世代火力発電と CO 2 削減 宝田恭之 群馬大学大学院理工学府環境創生部門

2 Mtoe Mtoe Global Primary energy demand and power generation by sources Coal is known as very important energy resource that has the characteristics distributed over a wide area and stable low price relatively, compared with others energy resources. Coal shares will be about 25% in Global Primary energy demand and about 40% in Global power generation in % 24% 47% 37% World primary energy demand by source World power generation by source Reference: World Energy Outlook 2002, 2004, ,

3 Importance of Coal in EAS Region for electricity demand Based on the data by IEAGHG, coal will remain the dominant power source in the EAS(East Asia Summit) Region Coal will continue to supply more than half of electricity in the EAS region by Capacity addition of coal-fired power stations are significant notably in China, India and ASEAN countries. Share of coal-fired power stations in the EAS region Coal-fired power generation by country Source) Compiled from IEA statistics Reference: John Gale, IEA GHG, JCOAL CCT Seminar

4 10 8 t/year Steam coal import Coking coal import Steam coal production Coking coal export Coal imports and production in Japan

5 Development of Clean Coal Technology by NEDO Carbon Capture Technologies Low carbonization in coal-fired power generation Improvement of power generation efficiency Development of CO 2 capture technology NEDO Projects IGCC (EAGLE STEP 1) 2006 Clean-up of synthesis gas for IGFC Establishment of Technology (Year) 2017 Entrained flow steam gasification 2030 Chemical/physical absorption (EAGLE STEP 2 & 3) Oxy-fuel IGCC Chemical looping combustion Low carbonization in iron and steel industry CO 2 capture & emissions reduction CO 2 emissions reduction in iron and steel industry (COURSE50 Project) Utilization of low rank coal Drying & upgrading Consideration of business model/ Demonstration abroad 4

6 [g-co 2 /kwh] Comparison CO 2 emission by power generation Even most efficient coal fired thermal power generation discharge about 2 times CO 2 compared to LNG- Fired. Coal fired thermal power generation needs Improvement of the efficiency and introduction carbon capture utilization and storage (CCUS) India China U.S. Germany World Coal Fired thermal power in the World 864 Coal Fired (Japan) USC IGCC IGFC Coal Oil Power (Japan) with CCS Coal Fired thermal power in Japan Reduction by CCS DOT:500 g-co 2 /kwh EIB: 550 g-co 2 /kwh LNG LNG (steam)(gas turbine combined) Reference :Central Research Institute of Electric Power Industry(2009) CO 2 Emissions Fuel Combustion (2012) 5

7 High Efficient power generation technologies 65% Power generation efficiency 60% 55% 50% 45% IGCC (Verification by blowing air) 40% Ultrahigh Temperature Gas Turbine Combined Cycle Gas Turbine Combined Cycle (GTCC) Efficiency: 52% CO 2 emissions: 340 g/kwh Ultra Super Critical (USC) Efficiency: 40% CO 2 emissions: 820 g/kwh Efficiency : 57% CO 2 emissions: 310 g/kwh Technological establishment: Around 2020 A-USC Advanced Ultra Super Critical (A-USC) Gas Turbine Fuel Cell Combined Cycle (GTFC) 1700 deg. C-class GTCC 1700 deg. C-class IGCC Efficiency: 46% CO 2 emissions: 710 g/kwh Target: Around 2016 Efficiency: 63% CO 2 emissions: 280 g/kw Technological establishment: 2025 Reduction of CO 2 by 10% Advanced Humid Air Gas (AHAT) Efficiency: 51% CO 2 emissions: 350 g/kwh Target: Around 2017 Reduction of CO 2 by 20% GTFC LNG thermal power Reduction of CO 2 by 20% Reduction of CO 2 by 30% IGFC Coal-fired thermal power Integrated Coal Gasification Fuel Cell Combined Cycle (IGFC) Efficiency55% CO 2 emissions: 590 g/kwh Target: Around 2025 Integrated coal Gasification Combined Cycle (IGCC) Efficiency: 46 to 50% CO 2 emissions: 650 g/kwh (1700 deg. C class) Target: Around 2020 Present Photos by Mitsubishi Heavy Industries, Ltd., Joban Joint Power Co., Ltd., Mitsubishi Hitachi Power Systems, Ltd., and Osaki CoolGen Corporation * The prospect of power generation efficiencies and discharge rates in the above Figure were estimated based on various assumptions at this moment. Around

8 Power-generating technology Power generating technologies Outline and characteristics of technology Technological establishment (Year) Transmissio n end efficiency (% HHV) CO 2 discharge rate (G-CO 2 /kwh) 1 USC - high temperature and pressure steam generated by a boiler. - Long experience & reliability A-USC - higher temperature and pressure steam turbine than USC. - Advanced type of USC with heat resistant materials AHAT - A single gas turbine power generation using humid air. - suitable for medium and small turbines GTCC (1700 dig. C class) 5 IGCC (1700 deg. C class) 6 GTFC 7 IGFC - combined cycle power generation technology using a gas turbine and a steam turbine A combined cycle power generation technology through coal gasification and combination of a gas turbine with a steam turbine A triple combined power generation technology combining GTCC with fuel cells This is a triple combined power generation technology combining IGCC with fuel cells Innovative IGCC (Steam entrained bed gasification) - adds steam to gasification furnace on the IGCC system. - reduces oxygen ratio and increases cold gas efficiency. Steam gasification + dry refinement 2030 Highly-efficient oxygen separation 2030~ Closed IGCC (CO 2 -capturing next-generation IGCC) - circulates CO 2 contained in exhaust gas as an oxidant throughout a gasification furnace or gas turbine or later 42 After CO 2 capture - 7

9 Pulverized Coal Fired Power Generation Technology (Ultra Super Critical Steam)

10 Low carbonization in coal-fired power generation Improvement of power generation efficiency USC Technical Summary This method ejects and burns pulverized coal in a furnace, generates high temperatures and pressure steam using a boiler, and then rotates the turbine with the steam to generate electricity. Characteristics As an extremely reliable and established technology, about half of domestic coal-fired thermal power generation plants (base on installed capacity), which is as high as approximately million kw, use this technology. Pulverized coal Boiler Steam Isogo Thermal Power Plant (Source: J-POWER s web sit Timing of technological establishment 1995 or later Coal Pulverized coal Exhaust gas ST Generator CO 2 discharge rate Approximately 820 g-co 2 /kwh Mill Air Transmission end efficiency (HHV) Approximately 40% Slug Feed Pump Condenser Cost Approximately 250 thousand yen/kw (The power generation cost verification WG of the Advisory Committee for Natural Resources and Energy, May 2015) (Source: JCOAL Japanese Clean Coal Technology (2007)) 9

11 10 Trend of the Power Generation Efficiency in major countries World highest level of Power Generation Efficiency in Japan CO2 Emission (Ave. in Japan) Efficiency is better than the other major countries more than 10 to 30% Ave. Gross Thermal Efficiency of Coal Fired Unit (LHV) Isogo Thermal Power in Japan Coal Oil LNG J-POWER Japan Germany England USA Australia China India

12 Low carbonization in coal-fired power generation Improvement of power generation efficiency Technical summary This is a highly efficient power generation technology that increased the steam temperature of the steam turbine to 700 deg. C and higher as a further temperature increasing technology based on USC. Characteristics This technology achieves 46% of the power generation efficiency (transmission end efficiency, HHV) almost without changing the conventional pulverized coal-fired thermal power generation system. Timing of technological establishment Around 2016 A-USC 35MPa, High-temperature and large-diameter piping material (Provided by Nippon Steel & Sumitomo Metal Corporation) CO 2 discharge rate Approximately 710 g-co 2 /kwh Boiler Transmission end efficiency (HHV) Approximately 46% Target cost To achieve a power generation unit cost equivalent to that of conventional turbine Steam Turbine (Source: The material for the 1 st Next-generation Thermal Power Generation Council (A-USC development promotion committee) (June 2015)) 11

13 IGCC : Osaki CoolGen (OCG) Demonstration Project Scaling up of IGCC with the results from EAGLE Project 166MW IGCC plant Syngas Treatment Coal Gasification Subsidized by METI until Mar.2016 and NEDO from Apr

14 Gasification Osaki CoolGen (OCG) Demonstration Project IGCC Air Air separation unit Coal Oxygen Gasifier Steam turbine Gas clean-up facilities Steam Gas turbine Combustor Syngas (CO, H 2 ) Air Compressor Generator HRSG (heat recovery steam generator) Stack CO 2 Capture Technology Shift reactor H 2 rich gas CO 2, H 2 Fuel Cell CO 2 Capture Technology Fuel cell H2 CO 2 CO₂ transportation and storage processes 13

15 A Brief History of Development of IGCC, IGFC in Japan Method Coal Feed Rate Output Year [t/day] [MW] '80 '85 '90 '95 '00 '05 '10 '15 '20 Air Blown Oxygen Blown , Lab. (HYCOL) 50 PP (EAGLE) 150 1, Lab. PP PP: Pilot Plant Supported by NEDO DP: Demonstration Plant PDU HYCOL EAGLE OCG (Commercial Operation) PP DP DP 14

16 The schedule for OCG Demonstration project CO 2 capture IGCC is to be demonstrated with the result from EAGLE Project. IGFC will be demonstrated with the result from the basic research of syngas clean-up IGCC optimization feasibility study 1 st Stage Oxygen-blown IGCC Design,Construction Operations testing 2 nd Stage CO 2 Capture IGCC FS Design, Construction Operations testing 3 rd Stage CO 2 Capture IGFC FS Design, Construction Operations testing 15

17 Overview of Nakoso Air-blown IGCC demonstration and commercial plant Nakoso 250MW IGCC Main specification output gasifier AGR 250MW(gross) Air-blown,dry-feed MDEA GT M701DA(1 on 1) thermal efficiency schedule 42%(LHV,net) operation start commercialization Nakoso IGCC demonstration is concluded with great success The first commercial IGCC in Japan Total gasification hour : 31,900hr Continuous operation hour : 3,917hr (World record as of )

18 IGCC Plants - Fukushima Revitalization Power 540MW 2 - Hirono 540MW IGCC (Completion Image) Source : TEPCO Homepage Supplement added by MHPS Nakoso 540MW IGCC (Completion Image) Nakoso #10 250MW IGCC (COD : ) Source : TEPCO & Joban JPC Homepages Supplement added by MHPS Schedule Environmental Impact Assessment Started Engineering Work Started Site Mobilization (Scheduled) Operation (Scheduled) Nakoso IGCC Hirono IGCC Major Specification Output 540 MWgross 2 Trains Gasifier Air-blown Dry Feed Gas Clean-Up MDEA Gas Turbine M701F4 GT (1 on 1) 2016 MITSUBISHI HITACHI POWER SYSTEMS, LTD. All Rights Reserved.

19 TIGAR process (Low rank coal and biomass) Atmospheric pressure Low temperature New Energy and Industrial Technology Development Organization Components of TIGAR are based on mature Fluidized Bed technology The low grade material (lignite, biomass) can be gasified, and applied to chemical raw material, fuel Applicable Fuel Combustor (heat emission) Circulation High temperature bed materials are circulated Coal (lignite) Bark Bagasse Unreacted char is burned with air Gasifier (heat absorption) Fuel Wood Palm Waste Air Steam Steam gasification 18

20 Development of TIGAR 2004~ Basic Test 6TPD Pilot Plant New Energy and Industrial Technology Development Organization Japanese Government (METI*) Support *Ministry of Economy, Trade and Industry NEDO Support at present 50TPD Prototype Plant EPC Demonstration Test At Present Commercial Plant Lab Scale Testing Bench Scale Testing Pilot Plant Testing Prototype Plant Testing Commercialized Scale Batch 0.1T/D 6T/D 50T/D 300~1000T/D Tests of basic reaction Yokohama Tests of gasification Yokohama Tests of continuous Yokohama Tests of overall process long operation Indonesia TIGAR 4units (1reserve) Coal feed : 3000 T/D (Substantially NH 3 : 1000 T/D) 19

21 Europe and America Asia Pacific High-efficiency coalfired power plant Utilization of low rank coal The others Total NEDO FS projects (business model/demonstration) 50 feasibility studies for 24 countries conducted since 2011 High efficiency coal-fired power plants (USC etc): 22 Utilization of low rank coal (gasification, upgrading, drying): 16 Number by country and by item Mongolia 2 2 China Taiwan 1 1 Vietnam Thailand 1 1 Indonesia Myanmar 1 1 India Sri Lanka 2 2 Kazakhstan 2 2 Uzbekistan, Tajikistan and Kyrgyz 1 1 Uzbekistan and Tajikistan 1 1 Kyrgyz 1 1 Australia USA Canada 1 1 Poland 2 2 Bulgaria 2 2 Turkey 1 1 Hungary, Romania and Serbia 1 1 Hungary 2 2 Bosnia and Herzegovina 1 1 Brazil 1 1 Total

22 Research for Project Development Using High-efficiency Coal Utilization Systems / Research for Developing Low Rank Coal firing IGCC Plant in Thailand Contents <Purpose> This research is to study conceptual design and project scheme of IGCC project by using low rank coal (lignite) produced in Thailand, which contains high moisture, sulfur with the characteristic of low ash melting temperature. Research includes coal sampling, tests and study of potential to reduce greenhouse gas (CO 2 ) emissions and other environmental impacts. <Duration> June, March, 2016 *IGCC:Integrated coal Gasification Combined Cycle <Participants>Mitsubishi Hitachi Power Systems, Ltd., Mitsubishi Heavy Industries, Ltd. Local low rank coal mine

23 NEDO Project Formation Research on High-efficiency CCT Project Formation Research for Bituminous Coal Firing IGCC in Poland content <Summary> This research is to study conceptual design and project scheme of IGCC project by using bituminous coal produced in Poland, which contains high ash content with the characteristic of high ash melting temperature. Research includes coal sampling, tests and study of potential to reduce greenhouse gas (CO 2 ) emissions and other environmental impacts. <Investigation period> September, June, 2016 <Contractors> Mitsubishi Hitachi Power Systems, Ltd., Mitsubishi Heavy Industries, Ltd. Reduced CO2 Emission IGCC:Integrated coal Gasification Combined Cycle

24 CO 2 separation and capture cost High Chemical absorption method CO 2 low emission Oxygen combustion method recirculates highly concentrated oxygen in exhaust gas. Separation and capture cost: 3000 yen level/t-co 2 For pulverized coal thermal power use a solvent, such as amine. Separation and capture cost: 4200 yen/t-co 2 Utilization of CO 2 This technology utilizes captured CO 2 to produce valuables such as alternatives to oil and chemical raw material Solid absorbent method reduces energy requirement and separate CO 2 by combining amine, etc. Low Storage of CO 2 To store separated and captured CO 2 in the ground. practical realization of CCS technology by around The plant for this business is under construction, and the storage will be initiated in Physical absorption method CO 2 absorbed into a physical For IGCC absorption solution under high pressure. Separation and capture cost: Approximately 2000 yen level/t-co 2 Around 2020 Closed IGCC the oxygen fuel technology to the IGCC technology. Membrane separation method separates by using a membrane which penetrates CO 2 selectively. Present Around 2020 * The cost prospect in the Figure was estimated based on various assumptions at present. Around

25 Cost of Electricity (yen/kwh) CO2 の費用 ( 円 / トン CO2) CO2 の費用 ( 円 / トン CO2) CO 2 Cost(yen/t-CO 2 ) Cost of electricity with CCS in the present conditions Increase 3yen/kWh by Carbon capture Carbon capture cost is 3,500yen/t-CO 2 3yen/kWh (1) 12,000 10,000 8,000 6,000 4,000 2,000 O&M of Storage CAPEX of Storage (2) O&M of Transportation CAPEX of Transportation 6,187 Fuel O&M of Power Generation CAPEX of Power Generation 12,000 9,892 10,000 8,000 6,000 4,000 2,000 (3) (4) 10,973 6,187 11,343 9,892 10,973 Storage 8,246 Transportation Liquefier and Pressurize Energy penalty (Cost increase by lowering of efficiency) Capture 3,500yen /tonco Without CCS Storage from onshore base Cost of electricity of IGCC with CCS 0 0 Storage from ケース1 ケース2 Storage ケース13 from Storage ケース24 from ケース53 ケ offshore base onshore base offshore base ( 輸送無 0km) (1259km) ( 輸送無 (1074km) 0km) (1259km) (704km) (120km) (1074km) (1 ( Cost of CO 2 洋上基地 分離 回収エネルギーペナルティ分離 回収液化 昇圧エネルギーペナルティ輸送液化 昇圧貯留 Offshore Base Storage from onshore base Storage from offshore base Aquifer CO 2 Storage area Aquifer CO 2 Storage area

26 IGCC Coal Firing Boiler CO 2 Capture Technologies Post Combustion CO 2 Capture Oxy-fuel CO 2 Capture Chemical Looping Pre Combustion CO 2 Capture (Chemical or Physical) CO 2 Membrane Separation Oxy-IGCC With Capture Unit Without Capture Unit 25

27 CO 2 separation and capture technologies CO 2 Separation and capture technologies Outline of technology Cost (Yen/t-CO2) Technical establishment (Year) 1 Chemical absorption method - utilization of chemical reaction between CO 2 and liquid. 4,200 yen * In the case of post combustion Already established 2 Physical absorption method - dissolved into a liquid for separation and capture. - The absorption capacity depends on the solubility of CO 2 into a liquid. 2,000 yen level Solid absorbent method - solid absorbent and absorption materials. (Solid solvent method) 2,000 yen level * Preliminarily-calculated Membrane separation method - separates a CO 2 from a mixed gas by utilizing the permeation selectivity of the thin membrane of a solid material with separation capacity. - Problem: scale up 1,000 yen level * Preliminarily-calculated Oxyfuel combustion method - separates oxygen from combustion air and burns fuel using this oxygen. 3,000 yen level Closed IGCC (CO 2 capture nextgeneration IGCC) - applied technology based on IGCC system. - circulates CO 2 in exhaust gas as an oxidizing agent throughout a gasification furnace and gas turbine. - Later than 2030 *1)The method for capturing CO 2 from the exhaust gas after combustion. *2)The method for capturing CO 2 from the fuel before combustion * The preliminary calculation of the costs in the above table is based on various assumptions and does not determine future separation and capture costs. 26

28 Development of CO 2 Capture Technology EAGLE Pilot Plant (150 tons/day) CO 2 Separation facilities Gas purifier Air separation facilities Gasifier (150 tons/day) Physical adsorption Chemical adsorption Gas turbine house (8 MW) STEP 1 ( ) STEP 2 ( ) STEP 3 ( ) - Oxygen-blown entrained-flow gasifier was developed - Gas cleanup technology was established - CO 2 capture technology (chemical absorption) was developed - Coal type diversification (high ash fusion temperature coal) was carried out - Development of CO 2 capture technology (physical absorption) 27

29 Development of CO 2 Capture Technology Chemical/Physical Absorption (EAGLE Stage-2 & 3) Method of CO 2 Capture Net Thermal Efficiency Loss of Efficiency With CO 2 Capture (Recovery Rate: 90%) Without CO 2 Capture 45.6% Chemical Absorption Heat Regeneration (conventional) Heated Flash Regeneration (newly-developed) 34.8% 10.8% 38.2% 7.4% Physical Absorption 39.2% 6.4% (With a 1,500ºC class gas turbine) Improvement: 3.4 points Further Improvement: 1.0 point A drastic reduction in loss of efficiency for CO 2 capture was achieved. It will be studied whether the cost of CO 2 capture can be reduced from USD 0.03/kWh to USD 0.02/kWh. (Higher Heating Value Basis) 28

30 Oxy-fuel IGCC IGCC with CO 2 capture which has no CO 2 capture unit nor shift reactor. Target net thermal efficiency is 42% with CO 2 capture. (Loss of efficiency is 2 points for CO 2 capture) The cost for CO 2 capture could be reduced from USD 0.03/kWh to 0.02/kWh. Syn Gas Combustor GT ST G Power Gasifier Coal O 2 CO: 66% H 2 : 24% CO 2 : 5% O 2 CO 2 recycle CO 2 GT: Gas Turbine ST: Steam Turbine G: Generator CO 2 recycle CO 2 capture Recover 100% of CO 2 Establishment of Technology: in

31 Air Combustor Fuel reactor Chemical Looping Coal Combustion Steam 蒸気 (Power generation) Water ( 発電 ) 給水 空 AR 気燃焼塔 Ash 灰 Fe 2 O 3 サイクロン Cyclone Coal 石炭 Heat 熱回収器 Recovery Stem 燃料 VR 反応塔 CR Fe 3 O 4 Stem 蒸気 蒸気 dust 集塵器 precipitator AR: Air Reactor 灰 CR: Coal Reactor VR: Volatile Reactor Stem 蒸気 脱水器 Ash Water N 2 N 2 Air 空気 煙突 Compressor 圧縮器 Stack Needs to develop /Iron based high performance and economy oxygen carrier /CLC process consists of threereactors based on CFB technology CO 2 Candidate of Oxygen Carrier CLC can avoid energy loss during the CO 2 separation, so the thermal efficiency of power generation can be maintained. Establishment of Technology: in 2030

32 Power generating cost, Japanese Yen/kWh CO 2 capture cost, Japanese Yen/ton-CO2 31 Economic comparison between CLC and PC with CCS The CO2 capture cost by current technology for PC is around 3,500 to 4,500 Yen(35-45$)/t-CO2. The 2,500 Yen(25$)/t-CO2 is a target for CLC development to get a commercial superiority in the market. Other variable cost Coal Depreciation CO 2 capture cost 11Yen/kWh Career Other Fixed cost 9 Yen/kWh Yen Yen Target Now Now CO 2 capture 90% Without CCS

33 まとめ 火力発電は 世界全体の電源構成の過半数を占める重要な電源である 新興国を中心に世界全体で今後も増加する電力需要を安定かつ効率的に満たすためには 再生可能エネルギー 原子力とあわせて活用していくことが不可欠である 一方 国際的には地球温暖化対策への対応は重要課題である こうした状況にあって 地球が蓄えた貴重な資源である化石燃料を有効に利用し 技術革新によって CO 2 削減の課題を克服しつつ 持続的な経済成長と地球温暖化対策の両立を実現していくことが我々の使命である 産学官の関係者が議論を重ねて取りまとめた本ロードマップは 我が国が次世代火力発電の技術開発を推進していく上で 重要かつ新たな出発点と思われる 最後に本ロードマップ作成に携わって頂いた産学官の関係者の皆様に謝意を表す 32