Development of pilot scale nanofiltration system for yeast industry wastewater treatment

摘要

The treatment of the yeast industry wastewater was investigated by nanofiltration (NF) membrane process on a pilot scale. Two wastewaters were used as feed: (i) dilute wastewater with COD 2000?mg/L and (ii) concentrate wastewater with COD 8000?mg/L. The permeate flux, COD retention, color and electrical conductivity (EC) removal were evaluated in relation to trans-membrane pressure and long-term filtration. A linear growth in permeate flux was found with increasing in trans-membrane pressure for wastewaters. In addition, the COD retention, color and EC removal increased with trans-membrane pressure enhancement. The results obtained from the long-term nanofiltration of dilute wastewater indicated that the permeate flux decreased from 2300?L/day to 1250?L/day and COD retention increased from 86% to 92%. The quality of the permeate in term of COD is lower than the discharge standard in river (200?mg/L). Thus, this process is useful for treatment of wastewaters produced by yeast industry.Keywords: Nanofiltration, Membrane process, Pilot scale, Wastewater treatment