Experimental studies on treatment of distillery effluent by liquid membrane extraction

Emulsion liquid membrane (ELM) as a technique for effluent treatment has received wide attention in recent years due to its ease of operation, lower power consumption and modular design. Odorous distillery effluent was treated for removal of acetic acid (solute) using ELM in a batch process. The effect of agitator speed, duration of agitation, xylene concentration in the membrane phase, membrane to external phase (M/E) ratio on the reduction of solute, concentration of biological oxygen demand (BOD) and chemical oxygen demand (COD) in the external phase has been studied. At 110 rpm, 4% xylene concentration and M/E ratio of 0.8, a maximum recovery of 44% solute and minimum values of BOD and COD of 96 and 927 ppm, respectively, in the external phase were observed. The experiment was also conducted in a York-Schiebel column at 110 rpm and the BOD and COD of treated effluent were 94 and 900 ppm, respectively, which is almost the same as that in a batch process.