撞击流气液吸收特性及用于甲醇合成应用研究

Study on Absorption Characteristics of Impinging Stream and its Application in Methanol Synthesis

在二氧化碳-水系统中,采用了压力式喷嘴对撞击流吸收特性进行了研究,结果表明压力式喷嘴压差增大和液体流量增加都能增加气液吸收速率,同时利用增强因子证明了撞击流能够有效地起到增强气液相间吸收速率的作用。对撞击流反应器用于甲醇合成反应进行分析,通过与具有液相合成工业运行实例的浆态鼓泡床进行对比,发现固含率(催化剂含率)低时(<20%),采用浆态鼓泡床或撞击流用于甲醇合成,反应速率为控制步骤;而高固含率时(>40%),浆态鼓泡床其控制步骤已经逐渐转变为传质和反应共同控制,甚至为传质控制,而采用撞击流形式化学反应速率仍为其控制步骤。在撞击流反应器内进行甲醇合成反应,从热模实验的角度证实了催化剂浆料多股撞击对甲醇合成催化剂时空产率带来的增强作用。

The absorption characteristics of impinging stream were studied by using the pressure type nozzles in carbon dioxide-water system. The results show that the gas-liquid absorption rate increases with the increase of the differential pressure of the nozzles and liquid flow rate. The enhancement factor was used to reveal that the impinging stream can really promote the absorption rate between the gas and liquid phases. Compared with using the slurry bubble column, the application of impinging stream in CH3OH synthesis was investigated, and the results show that when the solid holdup （catalyst holdup） is lower than 20% in mass, the control steps of the synthesis reaction in both slurry bubble column and impinging stream reactor are the reaction rate control; however, when the solid holdup is higher than 40%, the control step of the synthesis reaction in slurry bubble column changes to dual control of gas-liquid mass transfer control and reaction rate control, even to the gas-liquid mass transfer single control, while in the impinging stream reactor, the reaction rate control still keeps to be the control step of the synthesis reaction. The experiments of synthesis CH3OH in reactor with impinging streams show that the impact of multi-flow catalyst pastes sprayed from the nozzles can strengthen the productivity of the catalyst.