Working Fluid Selection of Organic Rankine Cycle Using Low-grade Waste Heat with Variable Inlet and Constant Outlet Temperatures

摘要

This paper presents selection of working fluids for non-regenerative subcritical organic Rankine cycle(ORC)with alkanes,fluorinated alkanes,ethers,fluorinated ethers,aromatics,linear siloxanes and alcohols as working fluids using PR equation of state.The ORC system is driven by the waste heat source with temperature between 120 oC and 300 0C,whose specified outlet temperature is 80 0C.The first law efficiency,overall heat transfer capacity,turbine size factor and environment are used for comparison of different cases.The suitable working fluids for ORC system at different cases are shown:(a)case I(120 0C-80 0C): R161,R152a,RC270,RE170,CF31,RE134,R600a,isobutene,1-butene,R600,trans-2-butene,cis-2-butene,R245ca and R60la;(b)case 2(160 0C-80 0C): RC270,RE170,isobutene,l-butene,R600a,R600,R245fa,trans-2-butene,cis-2-butene;(c)case 3(200 0C-80 oC): cis-2-butene,trans-2-butene,R60la,R601,1-butene,isohexane,n-hexane and isobutene;(d)case 4(250 0C-80 0C): cyclopentane,n-hexane,acetone,cyclohexane;(e)case 5(300 0C-80 0C): acetone,cyclopentane,cyclohexane,benzene.