丁二酸发酵液的膜分离过程研究

Study on Purification of Succinic Acid Broth by Membrane Separation

通过微滤、超滤等膜分离技术对丁二酸发酵液进行了分离纯化,考察了温度、压力差、pH值、循环流速等因素及操作方式对丁二酸分离的影响。丁二酸发酵液经稀释后可直接进行微滤操作,微滤的优化工艺条件为:pH5.0,40℃,△P=0.03MPa,循环流速0.71m/s,采用间歇反冲可降低膜污染程度,维持较高通量;微滤除菌率达99.6%,蛋白质去除率87%,脱色率92%。将得到的微滤液在20℃,pH5.0,△P=0.05MPa,0.83 m/s循环流速下进行超滤,滤液透光率≥60%,蛋白质质量浓度仅5mg/L。经2步膜分离,蛋白质去除率达99.45%,丁二酸收率达93%。

Succinic acid was purified from broth by microfiltration and ultrafiltration, the influence of parameters in separation such as temperature, pressure difference, pH, circulation flow rate and operation mode were studied. Succinic acid broth was diluted and microfiltrated in better conditions such as pHS. 0, 40℃, △P=0.03MPa, 0.71m/s;batch recoil operation can reduce membrane pollution; 95% bacterial cells were removed , the removal ratio of protein was 87% and ratio of decoloration was 92%. The filtrate from microfiltration was ultrafiltrated in better conditions such as 20℃, pH5.0, △P=0.05MPa, 0.83m/s, the light transmittance of filtrate from ultrafihration was above 60 % and concentration of protein was only 5mg/ L. Finally, after two step of membrane separation, the removal ratio of protein was 99.45% and the recovery of succinic acid was 93% .