PE-IGCC based gasification of low grade coal and biomass for distributed generation in the rural area

Transcription

1 2012 Seoul S&T Forum Oct. 31 ~ Nov. 3 PE-IGCC based gasification of low grade coal and biomass for distributed generation in the rural area B.J. Lee 1, Y.C. Hong 2, S.J. Lee 1, D.H. Shin 1, and others from KIST, KIER, Korea Univ., and NFRI 1 Handong Global University, 2 National Fusion Research Institute

2 Contents 1 What is PE-IGCC (Plasma Enhanced Integrated Gasification Combined Cycle)? - Introduction - Current status 2 PE-IGCC using the highly efficient gasifier - Recycling CO 2 by transforming into high value added product CO 2

3 Clean Energy Source: Coal Gasification 1 World leaders agree to develop clean coal energy Core tasks for climate change Coal gasification, carbon capture and storage 2 Clean usage of low grade coal is the main task Most of nations have the low grade coal mainly, not high grade one The price of low grade coal is $10~15, but high grade one is above $130 Require the cost down by advanced technology Possible Years of Exploitation Deposits Oil 39years billion barrels Natural Gas 61years trillion m 3 Coal (High grade coal < 60 years) 227years 984 billion tons

4 Overview of IGCC Energy generation technology gasifying coal and other low grade fuel producing gas composed of hydrogen (H2) and carbon monoxide (CO) removing impurities such as sulfur and ash using gas and steam turbines. Gasification Technology Present: Atmosphere, Temp = 1,000~1700, high pressure Innovation in Plasma Technology 4

5 What is Plasma? 4th state of matter neutral gas disassembled into ions and electrons. Total sum of ions and electrons is same, i.e., neutral electrically More than 99.9 % of universe is composed of plasma. Its temperature, density, flow etc. can be controlled by electromagnetism Solid Liquid Gas Plasma Principle of plasma generation it acts as catalytic convertor, especially chemical processes required for high temperature and pressure because of radicals, which is by-product of plasma generation 5

6 Plasma Enhanced Gasification 1 Current atmospheres, temperature > 1,000, high pressure required Preheating essential for operation, difficulties in operation/maintenance 2 Method of Improvement Pulverized coal supply or biomass Steam (100% water, H 2 O) supply Torch plasma generator O H O H 2 H O 2 Steam Plasma Pulverized coal C H C C C C H C H C H C C C H C high temperature (> 3,000 o C), 1 ATM process (small machine), and fast gasification CO 2 CO H 2 Electricity generation 6

7 Advantages of Plasma Enhanced Gasifier Kind of Supplying Coal Gasification Temperature/Flexibility Gasification energy obtained Gasification Pressure Existing Gasifier Utilize high quality coal (>6,000 kcal) mainly and medium moisture (<20%) and low lime content (<12%) coal with high energy capacity 1300~1700 o C (radiant heat)/only for more than 300 MW plant Oxidation of ~30% of coal 2~8 MPa PE-Gasifier Possible for the low quality coal with high lime content (<50%) and high moisture (<40%) 3000 o C (directly, saves preheating cost)/good for < 10 MW plant and gasifying biomass easily by modifying feeder Torch energy + ~ 15% coal oxidation 1 ATM pressure (0.1 Mpa) little volume gasifier O 2 Facilities Occupies >10% of total facility cost Saves >10% of facility expenses and also the operating cost by using steam Electricity usage rate Electricity used in O 2 facility (>10%) Density of Gasifying Catalyst Plasma torch uses 25~30% of the total electricity generation 1 10 times higher than existing gasifier CO 2 recycling Just capture capture and conversion to CO results in highly efficient gasifier Comparison Since the water plasma torch is used instead of the use of O 2 facility of existing gasifier and electricity, the gasification of low-quality coal is easy, thus, making it prior in cost and the best for the small power generator. The conversion of CO 2 to CO results in more CO 7

8 Basic parts for PE - gasification

9 Experiment in the beginning stage on the year of 2008

10 Parts and operation of about 25 kw gasifier

11 Characteristics of Coals used in the Test Proximate analysis (wt%) Jangseong Coal (KOREA) Shenhua coal (China) Brown coal (Indonesia) Moisture Volatile matter Ash Fixed carbon Ultimate analysis (wt%) Carbon Hydrogen Nitrogen Oxygen Sulfur Calorific value 4,060 6,465 4,190 (kcal/kg)

12 Gasification of Hard Coal (Anthracite, similar to Indian coal)

13 High grade coal (Shenhua) vs. Low grade coal (Brown) Shenhua coal steam 2.2 kg/hr Brown coal Comparison shows that the gasification result of brown coal and Shenhua coal is similar Cold gas efficiency based on the coal feeding 3.05 kg/hr and 4 kw microwave power N 2 : 20%, 218 lpm H 2 : 31%, lpm = 905.1mol/hr, CO: 25%, lpm = mol/hr, CO 2 : 20%, 218 lpm = 584 mol/hr, CH 4 : 4%, 43.6 lpm = mol/hr Q H2 = mol/hr 285 kj/mol = 71.6 kw Q CO = mol/hr 283 kj/mol = 57.4 kw Q CH4 = mol/hr 882 kj/mol = 28.7 kw Q Total = kw Q coal = 1 ton/day 4190 kcal/kg = 203 kw η (CGE) = kw/(203 kw kw) 100 (%) 61.2%, where kw represent the consumed power for plasma generation.

14 High moisture level of brown coal is an advantage in PE-IGCC High moisture level of brown coal is an advantage in PE-IGCC Steam plasma torch H 2 O H + OH d several micro meters D = 70 um Brown coal CO, CO 2, H 2 Brown coal is fed inside the steam plasma torch at temperatures >3,000 o C Rapid vapor expansion results in break down into smaller size coal powder. Simultaneously, the vapor decomposes into H 2, O 2 and OH, catalyzer. Greater surface area of smaller coal particles allow more efficient gassification Typical IGCC uses dry coal, requiring a separate heating process to remove the moisture of brown coal before being fed into the gasifier; Moreover typical IGCC operating temperatures of ~1,400 is not high enough to break down the coal into smaller sized particles. PE-IGCC gasifies high moisture coal well due to the high temperature of steam plasma. 14

15 Several kinds of gasifiers are being tested Vol. : ~ 63 L D : 300mm H : 1000mm Vol. : ~ 253 L D : 450mm H : 1500mm 25 kw 100 kw Vol. : ~ 1267 L D : 900mm H : 2000mm Vol. : ~ 2534 L H : 1200mm H : 2300mm 500 kw 1000 kw

16 25 kw PE-IGCC was constructed at NFRI Gasification, capture of CO 2 and the generation of electricity now 10 m x 13.7 m 500 kw gasifier operation at Whasung 1000 kw gasifier and electricity on next Feb. at Taebaek

17 CO 2 Capture system with control CO 2 absorbent : MDEA (methyl diethanol amine) Capacity : > 10 Nm 3 /hour Coal + Slurry O 2 ASU Gas Cooling Shift Rx (option) WGS CO 2 H 2 H 2 O Particulate Scrubber Steam Turbine Electricity Air Fines/Char HRSG Slag/Frit Compressed Air to ASU Combustion Turbine Electricity

18 Syn-Gas efferent duct 500 kw gasifier and parts 75kW MW System Gasifier Switch board Coal storage/supply tank

19 Coal Feeding System gasifier Coal storage/supply tank Ash Vessel 75kW MW System

20 Schematics of 2 MW PE-IGCC plant Pulverized coal distributor Syn-gas cooling / ash removal H 2 S removal gasifier Power supply x 8 CO 2 separator Syn-gas tank

21 Arrangement of 75KW Plasma torch for 2 MW gasifier

22 Experimental Set-up for Palm skin Power source : 2.45 GHz microwave Proximate analysis (wt%) Palm (Indonesia) Power : 5 kw Forming gas : 50 lpmair Palm skin powder: 1~8 kg/h (a) Moisture Volatile matter Ash 6.61 Fixed carbon Ultimate analysis (wt%) Pressure : Atmospheric-pressure Field applicator : microwave torch Pal m Carbon Hydrogen 6.04 Nitrogen 0.57 Oxygen Sulfur 0.04 (b) Calorific value (kcal/kg, db) 4,870

23 Results Plasma flames generated from palm skin powder + air plasma Power : 3kW, Swirl air : 30 L/min 3 kg/h -palm skin powder in (a) (b) Photographs of before the palm skin powder injection into the microwave plasma torch at a mixture of 30-L/min air as a swirl gas and during 3kg/h palm with 20-L/min air as a carrier gas. (b) Temperatures of the palm microwave plasmaburner flame at different balm-injection rates. The measured position was 15cm away from the upper wall of the papered waveguide Spectra showing the traces of product gases produced from the palm combustion at different palm-injection rates

24 Introduction of technology to produce CO from CO 2 Before and after the generation of electricity from the PE-IGCC plant, about 40 mol% and 60 mol% CO 2 is generated from the carbon of feeding coal The high temperature of microwave CO 2 plasma torch using captured CO 2 makes the reaction of carbon possible and results in synthesizing CO High throughput and lowest cost to produce CO compared to existing ways, such as thermal cracking of Naphtha and bunker fuel CO 2 plasma torch Sale carbon CO 2 CO Feed again

25 Experiment on CO 2 conversion C + CO 2 2CO, C plays the role of catalyst Patent technology CO 2 Microwave plasma torch works at 1 ATM pressure Because of free CO 2 cheapest way to synthesize CO

26 Total system to control CO and CO 2 Facility, which produces synthesis gas from gasifier, generate CO 2 plasma torch utilizing by-product CO 2, and synthesize CO by adding catalytic convertor C Since all CO 2 can be converted into CO basically, PE-IGCC is CO 2 free power plant Reaction Scheme -- double path CO production O 2 C + H 2 O CO + H 2 CO 2 + H 2 O + Power CO 2 Carbon CO CO 2 Carbon CO 1st CO synthesis 2nd CO synthesis

27 High grade coal (Shenhua)Vs. Low grade coal (Brown) Shenhua coal steam 2.2 kg/hr Brown coal Comparison shows that the gasification result of brown coal and Shenhua coal is similar Calculation of Cold gas efficiency based on the coal feeding 3.05 kg/hr and 4 kw microwave power N 2 : 20%, 218 lpm H 2 : 31%, lpm = 905.1mol/hr, CO: 25%, lpm = mol/hr, CO 2 : 20%, 218 lpm = 584 mol/hr, CH 4 : 4%, 43.6 lpm = mol/hr Q H2 = mol/hr 285 kj/mol = 71.6 kw Q CO = mol/hr 283 kj/mol = 57.4 kw Q CH4 = mol/hr 882 kj/mol = 28.7 kw Q Total = kw kw(co 2 CO) kw(co CO 2 CO) Q coal = 1 ton/day 4190 kcal/kg = 203 kw η (CGE) = kw/(203 kw kw) 100 (%) 61.2%, where kw represent the consumed power for plasma generation /(203 kw kw kw) 90%, where kw does the one for CO 2 conversion

28 Target markets distributed power plants Villages with low quality coal and biomass (rice husk, palm skin) but are too far away from other villages or power plants to receive electricity, namely off-grid source required Villages less than 2,000 people in India, China, Indonesia, Chile, and countries, where possess enough biomass ~ 500,000 villages in the world Less than 3 MW power is mostly enough for them High Grade Coal Mining Areas Low grade coal on average 30% found in high grade coal mines can be used to create small energy generator to overcome environmental issues and become energy independent Key areas include Australia, China, Canada, U.S.A., and Indonesia Cost saving by replacing high grade coal with low grade one A company using 1,200 tons of high grade coal per day can save up to 80% in coal prices using low grade coal. Providing both green electricity and CO to petrochemical factories Cheapest way to produce CO from free CO 2 by adding Carbon as a catalyst Most efficient power plant for petrochemical industry 28

29 Summary Since PE-IGCC can be CO 2 free power plant and makes poly-generation possible through the gasification of coal, it is the best technology for green coal. The high temperature (>3,000K) of plasma torch of PE-IGCC can gasify the low grade hydrocarbon fuel since much gasification catalysts, such as OH* and O*, are produced. PE-IGCC plant can play the role of the efficient off-grid source and can be utilized for any regional feedstock, such as any kinds of coal, sand oil, coffee powder wasted, wood chips, rice husk, palm skin, the powder of municipal waste, and more through controlling the ratio of CO 2 to CO efficiently. PE-IGCC plant can provide the green electricity and CO (basic raw gas for petrochemicals and high cost gas) from CO 2 plasma torch by adding cheap carbon source simultaneously into petrochemical factories.