3 MW_(th)煤化学链气化商业示范装置的自热运行和参数分析

Autothermal operation and parametric analysis of commercial demonstration unit of 3 MW_(th) coal chemical looping gasification

为实现MW_(th)规模化学链气化商业示范装置的自热运行,使用Aspen Plus进行模拟研究。通过实验数据,验证了过程模型的可靠性。考察了3 MW_(th)煤化学链气化系统的质量和热量平衡。通过分析反应器温度、蒸汽流率和温度、旋风分离器效率、载氧体活性成分含量等工艺参数对系统合成气产率、合成气组分浓度、合成气H_(2)/CO、固体循环流率等工艺性能的影响,确定了合成气产量最大化的自热操作条件。结果表明,3 MW_(th)煤化学链气化系统的净热功率越接近于0,系统越趋于自热运行。系统自热运行时的最佳操作条件为燃料反应器温度850℃、空气反应器温度950℃、蒸汽流率305.25 kg/h、蒸汽温度300℃、旋风分离器效率98%,系统的固体循环流率最小,约为10 555~10 580 kg/h,合成气总浓度(CO+H_(2))最大,约为75.1%。此外,使用活性成分含量较高的钛铁矿颗粒作为载氧体,有利于减少系统的固体循环流率。

Chemical looping gasification technology is an effective way to realize the efficient and clean conversion of solid fuel.The autothermal operation of MW_(th) scale chemical looping gasification is an important basis for the commercial application of this technology.Aspen Plus is used for simulation research in order to realize the autothermal operation of the chemical looping gasification demonstration unit.The reliability of the process model is verified by experimental data.The mass and heat balance of the 3 MW_(th) coal chemical looping gasification system is solved.By analyzing the effects of reactor temperature,steam flow rate and temperature,cyclone separator efficiency,oxygen carrier active component content,and other process parameters on syngas yield,syngas component concentration,syngas H_2/CO,solid circulation flow rate,and other process performance of the system,the autothermal operating conditions for maximum syngas production are determined.The results show that the net heat power of a 3 MW_(th) coal chemical looping gasification system is close to 0,and the system tends to autothermal operation.The optimum operating conditions are fuel reactor(FR) temperature of 850℃,air reactor(AR) temperature of 950℃,steam flow rate of 305.25 kg/h,steam temperature of 300℃,and cyclone efficiency of 98%.At the same time,the solid circulation flow rate of the system is the smallest,which is about 10 555~10 580 kg/h.The total concentration of syngas(CO+H_2) is the largest,which is about 75.1%.In addition,the use of ilmenite particles with higher content of active components as oxygen carriers is beneficial to reduce the solid circulation flow rate of the system.