Coal and Wood to Liquid Fuels Randall Harris

Transcription

1 Coal and Wood to Liquid Fuels Randall Harris Planning for a brighter future

2 Woody Biomass Utilization Routes Adopted from Fischer-Tropsch Technology, Steynberg & Dry

3 Biomass Fischer-Tropsch Diesel 66 Gal FT Wax 1 Ton Woody Biomass Gasification Synthesis 55 Gal FT Diesel Adopted from Fischer-Tropsch Technology, Steynberg & Dry

4 Woody Biomass Syngas Properties Synthesis Gas Balance Comp. Mole Weight Mass Rate Lbs/hr Mass % Mole Rate Lbmol/hr Mole Volume Fract. SCFM ACFM Flowing Density bs/ft3 Standard Density Lbs/ft3 CO % H % CO % CH % H 2 O % N % NO % O Ar % Associated Physics of America 2005, EGT-PHG-5 Synthesis Gas Specification

5 Biomass Operating Conditions SLOW PYROLYSIS YIELDS 1/3 CHARCOAL, 1/3 GAS AND 1/3 > VOLATILES (TAR) Adopted from Fischer-Tropsch Technology, Steynberg & Dry

6 Commercial Scale-Up 25-40,000 barrels per day 1 ton coal = 2 barrel 1 ton biomass = 1 barrel Type: single-stage entrained flow Gas flow: down Feed: dry fine coal/biomass Oxidant: preheated oxygen/steam Operating temperature: 2550F Operating pressure: 362 psig Gasifier lining: slag-coated membrane or refractory lining with water jacket Syngas cooling: water quench Ash form: slag (water quenched) Licensor: Siemens

7 Fischer-Tropsch Synthesis CO + 2H 2 Diesel CH 2 -+ H 2 O OR CO+2H 2 CH 3 OH Methanol O C O C C O H C O H C H O CH 2 O CH 3 CH 2 CH 3 CH CH 2 CH2 CH CH CH 2 CH CH 2 CH CH 2 CH CH CH 2 CH 2 The reaction implies a H 2 /CO ratio of 2 for the synthesis of the hydrocarbons, when lower catalytic Water-Gas Shift reaction Adopted from Fischer-Tropsch Technology, Steynberg & Dry

8 Synthesis Flow Diagram Adopted from Fischer-Tropsch Technology, Steynberg & Dry

9 Why Coal Co-Feed Treated wood wastes Charcoal SNG Untreated wood wastes primary processing Charcoal Methanol Recovered wood from forest operations, thinnings. Charcoal Gasification CO + H 2 Bio-diesel (FT) Dry urban wastes paper, cardboard Charcoal Hydrocarbons (FT) Coal Electricity Adopted from Fischer-Tropsch Technology, Steynberg & Dry

10 Heating Values 1.8 Biomass Atomic H/C ratio Coal Lignite Peat Wood Lignin Cellulose 0.4 Increased Heating Value 0.2 Anthracite Atomic O/C ratio From coal to biomass gasification: Comparison of thermodynamic efficiency Mark J. Prins, Krzysztof J. Ptasinskia, and Frans J.J.G. Janssen

11 C-H-O Diagram Coal yields 2 x CO (lowers fuel use) Wood yields 1.5 x H 2 (lowers water use) Fuel T ( 0 C) Air flow kg/kg fuel Product gas composition mole % CO H 2 CO 2 H 2 O CH 4 Coal Untreated wood Krzysztof J, Chemical Engineering Department, Eindhoven University of Technology

12 Carbon Storage Value Standing Timber Yearly Growth Harvested 13 tons wood 539 tons carbon carbon stored in typical house:

13 Woody Biomass and Coal to Liquids View coal as the starting point the expansion of biomass fuels View biomass as clean, renewable solar energy that has carbon storage built in offsetting GHG emissions of coal Fischer-Tropsch liquids have inherently lower levels of hazardous emissions than fuels produced in any other manner Forests and coal are co-located throughout Appalachia Fuel use of woody biomass with coal has higher economic value Fuel value Carbon offset value

14 Building a brighter future

15 Fuel Properties Fuel Proximate analysis wt% Moisture Ash Organic fraction Ultimate analysis wt% of organic fraction C H O N S Coal Vegetable oils Straw Treated wood Untreated wood Grass/plants Sludge Manure Krzysztof J, Chemical Engineering Department, Eindhoven University of Technology

16 Gasification Efficiency 90 Efficiency (%) Coal Vegetable oils Straw Treated wood Untreated wood Grass/plants Sludge Manure Based on Lower Heating Value Based on Chemical Exergy Based on Chemical & Physical Exergy Krzysztof J, Chemical Engineering Department, Eindhoven University of Technology