加压流化床反应器中煤焦化学链气化实验与数值模拟研究

采用CPFD模拟和实验相结合的方法，研究了0.1～0.5 MPa压力条件下，鄂尔多斯烟煤焦和Fe2O3/Al2O3载氧体(OC)的流动特性及气化反应行为。结果表明，颗粒体积分数是影响加压下煤气化速率和合成气品质的关键因素，当颗粒体积分数在1.0%～2.8%区间、操作压力从0.1 MPa加压至0.3 MPa时，煤焦气化速率增长2.7倍，合成气摩尔分数由72%增长至78%。操作压力及颗粒流态的改变对水煤气变换反应速率无显著影响，通过煤焦气化反应和载氧体还原反应的耦合可实现合成气组分比例的调控。XRD表征显示Fe基载氧体各还原态组分分布与模拟结果一致。操作压力升至0.3 MPa，载氧体还原反应速率的增幅减小，释氧量增大50.18%；继续升压至0.5 MPa，显著促进了载氧体还原反应速率的增加，但释氧量仅增加3.92%。

Experimental and NumericalResearch on Chemical Looping Gasification of Coal Char in a Pressured Fluidized Bed Reactor

Combined CPFD simulations and experiments were used to study the gasification of Erdos bituminous coal char with Fe2O3/Al2O3 under the pressure of 0.1-0.5 MPa. The results showed that the particle volume fraction was the key factor affecting the coal gasification rate and the syngas quality under given pressures. When particle volume fraction ranged from 1.0% to 2.8%, the gasification rate of coal char increased by 2.7 times and the syngas molar fraction increased from 72% to 78% with the pressure of 0.1-0.3 MPa. The composition of syngas was not obviously changed by the variations of pressure and particle fluidization during water-gas shift reaction. The XRD characterization explored that the distribution of each reduction state of Fe-base oxygen carrier (OC) was consistent with the simulation results. At the pressure of 0.3 MPa, the increase of reduction rate of OC was decelerated and the total oxygen release increased by 50.18%. With the pressure reaching 0.5 MPa, the reduction rate was significantly promoted, but the total oxygen release was increased by only 3.92%.