The Impact Of Selexol-based CO₂Capture Process On IGCC System Performance

The global climate issue caused by the emission of CO₂and other greenhousegas has been received extensive attention of the world. At present, the world hasreached a consensus on CO₂reduction issues. China has a large production andconsumption of energy, and has a responsiblity for CO₂reduction task. China shouldvigorously develop clean coal combustion technology depends on China’scoal-dominated energy structure, the integrated gasification combined cycle （IGCC）technology is one of the most representative clean coal combustion technology.There are two models of Selexol-based CO₂capture process, one is calledcombined removal model and other is separate removal model. This article isestablishd on the cryogenic distillation system, and completed the separation of H₂Sand CO₂in combined removal model. Then have a comparation of the combinedremoval model and separate removal model. Finaly analysis the impact ofSelexol-Based CO₂Capture process on IGCC system performance.By simulating and analyzing on the cryogenic distillation, we can get that theseparation tower has the best feed location and the best reflux ratio, and the choiceof plate number should consider the impact of both the initial investment and energyconsumption. When the pressure of the system is19bar, the system has theminimum energy separation. When the product of CO₂use for EOR has a lowerenergy consumption than for a typical product.By comparing the combined removal model and separate removal model, wecan obtain that combined removal model has less solvent consumption、higher CO₂purity and higher CO₂、Sulfur recovery, and the power consumption reduced by43.23%. So combined removal model is superior to separate removal model. Whilethe energy consumption of the cryogenic distillation process accounted for81.9%ofthe total energy consumption of the combined removal system, so reducing theenergy consumption of the cryogenic distillation process is the key of optimizationresearch.Compared with the conventional IGCC power plants, Power generationefficiency and power efficiency of the IGCC system with CO₂removal was reducedby0.72%and4.02%. In the IGCC system with CO₂removal, When the product ofCO₂use for EOR, the system’s power supply efficiency has a0.16%higher than usefor typical product. For the different composition of coal, the change of IGCCsystem efficiency is subjected to the disappointment of oxygen consumption andsynthesis gas composition, content and other factors.