膜基气体吸收过程中活化剂的活化性能比较

Comparison of Activating Performance of Activators in Membrane Gas Absorption

将AMP(2-甲基-2-氨基-1-丙醇)和PZ(哌嗪)作为活化剂,分别添加于MDEA(N-甲基二乙醇胺)溶液中组成复合溶液,在膜吸收装置上考察了其吸收CO2性能.通过气液流速、气相组成、液相浓度、负载、膜组件结构和膜结构形态等对总传质系数Kov影响的比较,研究了具有多氨基环状结构的化合物PZ和空间位阻结构的化合物AMP在膜气体吸收过程中对传质的加强作用.结果表明,多氨基化合物PZ比空间位阻胺AMP活化效应更大,PZ对传质的加强作用高于AMP,流体力学因素对传质的影响有限,活化剂的化学活化作用对传质的影响是关键性因素,动力学因素对传质具有本质上的作用.

Piperazine （PZ） and 2-amino-2-methyl-1-propanol （AMP） as activators were added into methyldiethanolamine （MDEA） to form complex aqueous solutions, respectively. Mass transfer performance of CO2 absorption into the complex aqueous solutions in membrane contactors was studied. The effects of various factors, such as flowrates of gas and liquid, CO2 concentration of feed gas, absorbent concentrations of the solutions, CO2 loading in the solutions, configuration of membrane, and structures of modules on overall mass transfer coefficients of membrane contactors were investigated. Emphatically, the enhancement of mass transfer in membrane contactors was evaluated by means of comparison of chemical activation of sterically hindered amine AMP and multi-amino PZ in the complex solutions. The results show that multi-amino PZ has higher activation than sterically hindered amine AMP in complex solutions. The enhancement of PZ to mass transfer is higher than that of AMP in membrane contactors. The effect of hydrodynamics on mass transfer is limited. Chemical activation of activators is the key influential factor on mass transfer. Reaction kinetics plays a significant role in mass transfer.