液相共存成分对氨法脱碳吸收液解吸CO_2的影响研究

Influence of liquid coexisting components on CO2 desorption from decarburization absorbing solution by ammonia method

考察了烟气中SO2、NOx和CO2与氨水的反应机理,研究了模拟解吸液解吸过程中主要液相共存成分,如(NH4)2SO3、(NH4)2SO4、NH4NO3、NaCl、NH4Cl和(NH4)2CO3对CO2解吸的影响。研究表明,不同液相共存成分、质量分数、pH值、表面张力等对CO2解吸产生一定影响,大部分液相共存成分的存在,会降低脱碳溶液CO2的解吸量。质量分数低于10%的液相共存组分对脱碳吸收液CO2解吸过程的制约作用依次为(NH4)2SO3>NH4NO3>(NH4)2SO4>NaCl>(NH4)2CO3。因此,在碳捕集前应对烟气中的杂质成分进行脱除,减少其对解吸液理化特性的影响。

The reaction mechanisms of SO2, NOx, CO2 with ammonia solution were described. And the liquid coexisting components related to the desorption of simulated decarburization solution, including （NI-/4 ）2SO3, （ NH4 ） 2SO4, NI-I4NO3, NaC1, NH4C1 and （ NH4 ） 2CO3, were analyzed. The results show that the desorption of CO2 is affected by the mass fraction of liquid phase coexistence components, pH of solution and surface tension. Most of liquid coexisting components could reduce CO2 desorption of decarburization solution. The restraining effect of liquid coexisting components with the mass fraction less than 10% in the decarburization absorbent liquid on CO2 desorption is as follows ： （ NH4 ） 2 SO3 〉NH4 NO3 〉 （ NH4 ） 2504 〉NaCI〉 （ NH4 ） 2 CO3- It is necessary to remove the impurities in flue gas before CO2 capture, because the purities are harmful for CO2 desorption due to the hazardous effects on the physical and chemical characteristics of decarburization solution.