煤气化费托合成/电联产系统建模及热力学分析

Modeling and analysis for coal gasification co-production system of Fischer-Tropsch synthesis liquids and electricity

建立包括分布参数F-T合成反应器模型、考虑燃料气热值的燃气轮机模型及其他能够体现内部关键参数耦合关系的系统级单元子模型,并用于研究集成联产系统的整体热力学性能。首先,对合成气H2/CO、表观气速对F-T合成反应器合成气转化率和F-T合成尾气组成影响分析,结果表明F-T合成尾气存在CO/H2提高、CO2增浓的特点。综合考虑F-T合成反应器合成气转化率和反应器烃产率,推荐适合F-T合成的表观气速范围为0.15~0.40 m.s-1。其次,在燃气轮机模型部分,改变透平叶片高度来实现因燃料变化而引起的透平与压气机通流量的重新匹配,借助量纲分析法建立起透平通流面积与冷却叶片空气流量的函数关系式,并用于预测燃料组成和热值对燃气轮机性能的影响,提出了一种体现燃料气组成及热值影响的燃气轮机建模方法。最后,耦合F-T合成与燃气轮机模型,对不同H2/CO条件下煤气化F-T合成燃料/电联产系统整体性能预测,推荐了一套工艺流程简单且较单产系统具有热力学性能优势的联产系统方案。

Sub-unit models involving Fischer-Tropsch（F-T）synthesis reactor with distributed parameter,gas turbine model considering the fuel gas heating value and other related unit model were established.Based on the models integrated performance of coal gasification co-production system for F-T liquids and electricity was studied.Firstly,impaction of H2/CO in synthesis gas and superficial velocity on F-T reactor were analyzed,and the results showed that suitable supercritical gas velocity was at 0.15—0.40 m·s-1,considering the syngas conversion and hydrocarbon productivity of F-T reactor.Secondly,in gas turbine model,the turbine blades height was adjusted to reach mass flow rate match of compressor and turbine when fuel gas changed,and function relationship between cooling air and turbine flow area was established through dimensional analysis method,and then a suitable gas turbine model reflecting the fuel gas composition and heating value was proposed.Finally,coupling F-T reactor model and gas turbine model were built,integrated performance of coal gasification co-production system of F-T liquids and electricity was studied at different H2/CO,and a co-production system with simple process and thermal performance advantages was recommended.