Case Study of the Lignite-fired Power Plant with CCS

Transcription

1 UJV Rez, a. s. Case Study of the Lignite-fired Power Plant with CCS Dr. Olga Ubra Lukas Pilar, Monika Vitvarova, Jana Vavrova June 3-5, 2014 PowerGen 2014, Cologne

2 Organizations cooperating on CCS in the Czech Republic CZECH TECHNICAL UNIVERSITY IN PRAGUE UJV REZ, a. s. Research end engineering company for the Czech energy sector CZECH GEOLOGICAL SURVEY Main coordinator and investigator of the national projects on CCS research INSTITUTE OF CHEMICAL TECHNOLOGY PRAGUE 1

3 AGENDA 1. Introduction Czech Republic conditions in the field of CCS technology 2. Aim of the study 3. Input data for the study 4. Description of ammonia scrubbing and oxyfuel combustion 5. Techno-economic assessment - methodics 6. Main results and conclusion 2

4 1. Introduction Czech Republic conditions in the field of CCS technology 2. Aim of the study 3. Input data for the study 4. Description of ammonia scrubbing and oxyfuel combustion 5. Techno-economic assessment - methodics 6. Main results and conclusion 3

5 Czech Republic conditions Total emissions of CO 2 : 127 Mt/year Over 60% of electricity is produced by combusting local lignite (high ash and sulphur content) Subcritical steam power plants MW units, retrofitted 4

6 Czech Republic conditions Czech Republic CO 2 storage potential: 3,300 Mt Optimal storage sites: Deep saline aquifers sandstones and claystones (Central Bohemian permian-carboniferous basin, Neogene sedimentary complex of the Carpathians) 5

7 1. Introduction Czech Republic conditions in the field of CCS technology 2. Aim of the study 3. Input data for the study 4. Description of ammonia scrubbing and oxyfuel combustion 5. Techno-economic assessment - methodics 6. Main results and conclusion 6

8 Aim of the study Economic evaluation of the power unit with CO 2 capture Postcombustion CO 2 capture by ammonia scrubbing CO 2 capture after oxyfuel combustion Comparison of the power unit with CO 2 capture to the reference power unit without CO 2 capture Evaluation of impacts of the CO 2 capture technologies investigated on the electricity production costs Selection of the CO 2 capture alternative 7

9 1. Introduction Czech Republic conditions in the field of CCS technology 2. Aim of the study 3. Input data for the study 4. Description of ammonia scrubbing and oxyfuel combustion 5. Techno-economic assessment - methodics 6. Main results and conclusion 8

10 Input data for the study National project partially supported from public resources: Research and development of methods and technologies for CO 2 capture in the fossil fuel power plants and CO 2 storage into the geological formations in the Czech Republic Duration: Main fields of interests covered: a) CO 2 capture b) CO 2 transport c) CO 2 storage d) techno-economic analysis 9

11 Input data for the study CO 2 capture phase Postcombustion CO 2 capture by ammonia scrubbing Oxyfuel combustion - investigation and comparison of technologies CO 2 storage phase Evaluation of the CO 2 interaction with potential storage rock environment Tools for CO 2 storage risk assessment Assessment of the CO 2 storage public acceptance CO 2 transport costs Techno-economical phase Impacts of the investigated capture technologies on the electricity production costs Selection of the variant with the minimal negative impact 10

12 Input data for the study Main parameters of the reference power unit PARAMETER PHYS. UNIT VALUE Power output MWe 250 Lignite consumption t/h 214 Heat in fuel MWt 588 Auxiliary power supply (own MWe 24 consumption) CO 2 production t/h 211 CO 2 emissions in the air t/h 211 Electricity production MWe 226 Total net efficiency %

13 Input data for the study Flue gas parameters PARAMETER PHYS. UNIT VALUE PARAMETER PHYS. UNIT VALUE Dry flue gas Nm 3 /h 766,045 NO x mg/nm CO 2 vol% Solid pollutants mg/nm O 2 vol% 5.44 Vapor Nm 3 /h 218,493 N 2 vol% Water kg/h 80 SO 2 mg/nm Temperature C 62 SO 3 mg/nm

14 1. Introduction Czech Republic conditions in the field of CCS technology 2. Aim of the study 3. Input data for the study 4. Description of ammonia scrubbing and oxyfuel combustion 5. Techno-economic assessment - methodics 6. Main results and conclusion 13

15 Postcombustion ammonia scrubbing of CO 2 Technical constituents of the ammonia scrubbing technology 1. Raw flue gas/ clean flue gas heat exchanger 2. Flue gas cooling 3. Flue gas fan 4. CO 2 absorption 5. Clean flue gas after-cleaning 6. CO 2 desorption 7. Desorbed CO 2 polishing/cooling 8. CO 2 compression 9. Cooling water circuit 10.Auxiliary cooling source 11.Ammonia management 14

16 Postcombustion ammonia scrubbing of CO 2 15

17 Postcombustion ammonia scrubbing of CO 2 Effects of CO 2 absorption capture technology on the existing power plant production technology Impact on thermal cycle of the power unit and reduction of electricity production (steam extraction for desorption) Desorption column Middle/low pressure steam, 270 C, 75 t/h Increase of auxiliary power supply Compressor cooling, fan cooling towers, flue gas fan, multistage CO 2 compressors 50 MWe Impact on water management Two cooling circuits flue gas cooling, heat removal from compressor cooling CCS technology: t/h; first filling: 9,086 t; wastewater: 56.4 t/h Layout requirements 16

18 Postcombustion ammonia scrubbing of CO 2 : Summary Parameter Unit Reference With CC 17 Gross electric output MWe Coal consumption t/h Energy in fuel MWt Self-consumption MWe CO 2 production t/h Captured CO 2 t/h Emissions of CO 2 t/h Energy consumption of Carbon Capture MWe 0 50 Net electric output MWe Total efficiency % Efficiency decrease %

19 Oxyfuel combustion Technical constituents of the oxyfuel technology 1. Oxygen plant 2. Fluidized bed coal drying plant 3. Boiler 4. Electrostatic precipitator 5. Flue gas fan 6. Flue gas desulphurization 7. Flue gas condenser 8. CO 2 purification and compression 18

20 Oxyfuel combustion 19

21 Oxyfuel combustion Preliminary design of the boiler with oxy-combustion in comparison with the air-combustion case Air-combustion Oxy-combustion Parameter Unit AIR OXY Boiler efficiency % Flue gas recirculation % Outlet flue gas temperature C Furnace ground plan m 15x15 12x12 Surface area of ECO % Surface area of evaporators % Surface area of superheaters % Surface area of reheaters % A brand new boiler has to be constructed for oxy-combustion to meet the required heat transmission and flue gas flow conditions retrofitting of the air combustion boiler for the oxyfuel combustion is not an option. 20

22 Oxyfuel combustion Effects of oxyfuel technology on the existing power plant production technology Electricity consumption Main disadvantage, 35% of produced electricity (91.7 MWe) Demands on cooling Flue gas condenser, CO 2 compression: 447 MWt of waste heat Heat consumption Adsorption air drier regeneration (cryogenic plant): 3.2 MWt CO 2 adsorption drier regeneration: 270 kwt Raw materials consumption Water, coal, air limestone New types of waste 21

23 Oxyfuel combustion: Summary Parameter Unit Reference With CC 22 Steam output of the % boiler Boiler efficiency t/h Oxygen plant t/h O capacity Flue gas flowrate m 3 /s Gross efficiency % Gross electric output MWe Coal heating value MJ/kg Energy in fuel MWt Self-consumption MWe CO 2 production t/h Captured CO 2 t/h Emissions of CO 2 t/h Net electric output MWe Total efficiency % Efficiency decrease pp 0 8.2

24 1. Introduction Czech Republic conditions in the field of CCS technology 2. Aim of the study 3. Input data for the study 4. Description of ammonia scrubbing and oxyfuel combustion 5. Techno-economic assessment - methodics 6. Main results and conclusion 23

25 Techno-economic assessment - methodics The following proposed variants of lignite fired power plants were analyzed: Variant A lignite-fired power plant without CCS technology considered as a reference power plant Variant B1 - lignite-fired power plant with oxyfuel combustion CCS technology Variant B2 - lignite-fired power plant with oxyfuel combustion CCS technology and integrated WTA coal drier Variant C lignite-fired power plant with post-combustion CCS technology ammonia method 24

26 Techno-economic assessment - methodics Calculation process was divided into two phases: the operation-balancing phase the economic phase The objective of the operation-balancing phase: calculation of the annual operational balance required input data for economical computations Economic phase considered: annual operational costs investment costs other economic parameters 25

27 Economic parameters input data Technical/economic parameter Unit Value 1 EUR = 25 CZK 26 Time of operation h/year 6,300 Fuel price CZK/t 360 Raw water price CZK/m 3 4 Limestone price CZK/t 670 NaOH price CZK/kg 7.6 H 2 SO 4 price CZK/kg 3 NH 3 price CZK/kg 13.3 Waste water treatment CZK/m Emission permit price CZK/t 150 Electricity selling price CZK/MWh 980 Lifespan years 25 Construction time years 4 Fixed costs on workers CZK/year 39,200,000 Fixed costs other (coef.) % 1

28 Economic parameters input data Technical/economic parameter Unit Value Technical/economic parameter Unit Value Annual price growth + discount rate Fuel % 4 Chemicals % 2 Emission % - permits Electricity % 5 Other costs and % 1 yields Discount rate % 8 Investment rate 1. year % year % year % year % 20 27

29 Techno-economic assessment - methodics Sensitivity analysis CO 2 transport costs and CO 2 geological storage cost were calculated: Transport costs: 35 CZK/t (1.4 EUR/t) Storage costs: 87 CZK/t (3.48 EUR/t) The calculated price for a separated ton of CO 2 consisted of 75% by costs of its separation 8% by transport costs 17% by CO 2 storage costs 28

30 1. Introduction Czech Republic conditions in the field of CCS technology 2. Aim of the study 3. Input data for the study 4. Description of ammonia scrubbing and oxyfuel combustion 5. Techno-economic assessment - methodics 6. Main results and conclusion 29

31 Conclusions Criterium A B1 B2 C CAPEX (mil CZK) 12,813 16,886 18,512 18,100 OPEX (mil CZK) COE (CZK/MWh) 1,007 1,535 1,542 1,647 LCOE (CZK/MWh) 1,241 1,895 1,899 2,030 Costs on CO 2 separation/coe (CZK/t) Costs on CO 2 separation/lcoe (CZK/t)

32 Conclusions Implementation of CCS technology into the 250 MW lignite-fired power plant impacts: Increase of investment costs in the range of 37-44% Decrease of annual operation costs by 11 16% thanks to emission permits cost reduction (carbon permits) Increase of costs of electricity (COE) or levelized costs of electricity (LCOE) by 40 50% or 53 63%, respectively. Criterion of limited investment costs proves non-profitability of power plants with implemented CCS technology in existing conditions, in particular due to high investment costs and present sale price of electricity that is at low level at the stock exchange with minimum trend of growth in the forthcoming years 31

33 Conclusions Sensitivity analysis results Parameters influencing economic criteria values: high rate of investment costs, price of fuel, equipment lifespan and annual availability/operation of given energy source. A change of the relevant parameter by ± 50% impacts the economic criteria by even more than ± 20% Price of emission permits has relatively small impact on economic criteria values. A change of an emission permit price by ± 50% impacts the value of economic criteria by ± 6% max. 32

34 Conclusions Selection of CO 2 capture methods For newly designed and realized coal/lignite fired power plants the oxyfuel combustion technology variant appears to be more effective. This variant has lower losses and energy demands which plays more significant role especially at longer lifetime and higher annual availability/operation of the power plant Requirements for large scope modification of the existing equipment Integration of CCS technology into an existing coal/lignite fired power plant the post-combustion technology (ammonia method) appears economically more effective Decrease of operation costs in the oxyfuel combustion technology variant would not outweigh the higher investment costs 33

35 THANK YOU FOR YOUR ATTENTION