The Energy Utilization Research On IGCC Polygeneration System

Owing to human sustainable development, resource, energy, andenvironment optimization become important topic in twenty-first century. coalgasification polygeneration system is a important sustained developmentapproach in energy field againsting energy increases, liquid-fuelshortage, environmental pollution and a series of problem facing in ourcountry. the thought is breaking the bounds of different trades, based on coalgasification, combined independent procedure of production in energy, chemical industry and metallurgy field, through coupling and optiming inprocedure of production. the result is simplifier each products process flow andequipment. reduce the investing and operation cost, accordingly, reaching totalefficiency optium and population minium.This thesis firstly drafte polygeneration system, the system model is based onIGCC system, increased water-gas transformation, decarburation and methanolsynthetic reactor, and combined IGCC system and methanol synthetic systemorganicly.consequently, this model mostly include: coal gasification, gaspurification, methanol synthesis and combined cycle power generation.throughcalculating the thesis educed: in methanol-power connection in seriespolygeneration system, if methanol synthesis reached equilibrium state, thesystem total heat efficiency is 53.2%, compare with separate producing system, the methanol and power producing in the polygeneration system per 1kg coalcan reduced 0.021kg coal consumption, namely, the heat efficiency inpolygeneration system can increased 2.1%. in every system thermal loss, condensate thermal loss in steam turbine is maximal, occupyed 13.86% intotal system energy, oxygen generating power-wasting also occupyed sizablespecific weight.Secondly, the thesis analyze and majorize the polygeneration systempartically.through analyze operate parameters of gasifier, the thesis educed: ifthe ratio of carboatomic and oxygeniumic approaching 1.0, the carbon percentconversion can reaching 98%～99%, the cooled coal gas efficiency is maxium atthis time.through analyze water-gas transformation process, the thesis educed: ifthe transformated gas from Shell gasifier, the ratio of steam and gas between0.1～0.3, the temperature is almost not effect the ratio of H₂/CO of egresstransformation, and if the ratio of the steam and gas is 0.3, aftertransformation, the ratio of H₂/CO already reaching the requirement of methanolsynthetic system, so selecting the temperature of transformation primaryconsiderate subsequent handling and the catalyst requirement. inmethanol-power connection in series polygeneration system, if methanolsynthesis reaching 80% equilibrium state, the methanol and power producing inpolygeneration system per 1kg coal, in separate producing system, the coalconsumption is more than 1.0kg.namely, the heat efficiency in polygenerationsystem is higher than separate producing system, if methanol synthesis reachedequilibrium state, the IGCC system became methanol-power connection inseries polygeneration system, the heat efficiency can increase to 53.2% from40%.through analysis different recycle ratio effect the efficiency of entiresystem, the thesis educed: if the recycle ratio is 4.0, the efficiency ofpolygeneration system is maximum.Finally, the thesis conclude: the polygeneration system is a clear energysystem based on coal gasification, combined the characters of IGCCsystem, enhance the whole system efficiency, and pollutant effluent can reachedlittle degree, so polygeneration system have great development potential.