Research On The Key Technology Of Coal Based Polygeneration System (TCCUC)

Thermo-chemical comprehensive utilization of coal(TCCUC)process is a coal based polygeneration system based on low temperature coking coal.The new process included coal topping,semi-coke oxygen-rich direct combustion and high temperature gas cleaning,gas turbine power generation,steam turbine power generation,CO2 capture,value-adding treatment of topping gas products.High value chemical utilization of coal was achieved with appropriate pyrolysis of macromolecular hydrocarbons in coal and with hydrogenation of tar to get hydrocarbon liquid fuels.Thermal efficiency was further raised through comprehensive utilization of high level thermal energy with high temperature dust-removal,combination of gas turbine and thermal power generating units.Based on literature research and in-depth analysis of the TCCUC process,the process and equipment were matched.The coal pyrolysis module,oxygen enriched combustion module and gas steam combined cycle module were established,and the key parameters of the module are integrated.Coal gasification model,oxygen enriched combustion model,two stage combustion model,gas turbine cycle model and steam turbine cycle model were established.By using the simulation platform in the Aspen Plus,the operating parameters of each model were optimized to get the best cycle efficiency.The optimized cycle efficiency could reached52.06%,which is higher than the ultra super critical and IGCC cycle efficiency,at the same time,slightly lower than the combined cycle efficiency of natural gas.Therefore,TCCUC is more suited to the conditions of China's energy utilization,where coal is the primary energy consumption.The high temperature materials are the key role in the dust removal of the semi-coke oxygen-rich direct combustion products.The platform was built to test the high temperature resistance of the materials,in cluding the carbon fiber and steel fiber.The carbon fiber has a weight loss in the oxidation atmosphere of 400?,and the performance is decreased.However,carbon fiber could has a little weight loss in the micro oxygen atmosphere with the temperature of no less than 400?.The further studied showed that carbon fiber could be enhanced by coating SiO2.The best content of PDMS was 10%.Modified materials could be reach the dust removal process requirements of 400 ?,in which the weightlessness was 3.71% after 20 h in the oxidation atmosphere of 400?.The Stainless steel fiber of weight no change,at the same time the relative permeability coefficient and pore size have slight change after 120 h in the oxidation atmosphere of500-700 ?.So the performance of stainless steel fiber was stabled,which has great potential for industrial applications as high-temperature filter material.