草浆黑液超滤过程传质机理的初步研究

Mass Transfer in Pulping Black Liquor Ultrafiltration

通过与标准物质聚乙二醇超滤传质的比较研究，探讨了草浆黑液超滤的传质特性；超滤过程能耗的分析，揭示了能耗变化的规律。研究发现传质阻力首先来源于膜孔堵塞和膜污染，而且传质过程存在分阶段现象。文中黑液超滤传质理论描述，是通过研究膜压力的影响和能耗变化而提出的，从理论区分了传质的渗透压控制和凝胶层控制，有利于有针对性地解决黑液膜分离问题。

Mass transfer coefficient is employed as a standard for comparison in nonwood black liquor and ultrafiltration is discussed in the paper. The results show that the most important factor affecting mass transfer in ultrafiltration of black liquor is membrane fouling(polarization).The effects of the pressure gradient across membrane and energy dissipation are discussed. It is found that the mass transfer in ultrafiltration can be calculated with osmotic pressure model or the gel layer model.