摘要
This pilot study involved the application of a crossflow ultrafiltration （UF） membrane module employing hollow fiber polysulphone membranes in the reclamation of protein and oligosaccharides from soy protein wastewater. The optimal membrane molecular weight cut-off （MWCO） was selected as 10 ku upon retaining ratios of protein and oligosaccharides as well as the variation of permeate flux. The effects of pretreatment strategy and operating conditions, such as transmembrane pressure （TMP）, feed pH and velocity on flux were studied. According to the experimental result, the optimal operating conditions were determined as temperature 45 ℃, pH 4.5, TMP 0.2 MPa and feed velocity 10 L·s^-1. In addition, the permeate flux recovery by pure water backflushing and chemical cleaning was investigated. The experimental result showed that backflushing with pure water could only recover the lost permeate flux by 30%, and the decrease of backflushing interval was helpful in improving UF permeate productivity. Chemical cleaning test revealed that the combination of sodium hydroxide and EDTA was an ideal agent for cleaning the fouled membranes.
This pilot study involved the application of a crossflow ultrafiltration （UF） membrane module employing hollow fiber polysulphone membranes in the reclamation of protein and oligosaccharides from soy protein wastewater. The optimal membrane molecular weight cut-off （MWCO） was selected as 10 ku upon retaining ratios of protein and oligosaccharides as well as the variation of permeate flux. The effects of pretreatment strategy and operating conditions, such as transmembrane pressure （TMP）, feed pH and velocity on flux were studied. According to the experimental result, the optimal operating conditions were determined as temperature 45 ℃, pH 4.5, TMP 0.2 MPa and feed velocity 10 L·s^-1. In addition, the permeate flux recovery by pure water backflushing and chemical cleaning was investigated. The experimental result showed that backflushing with pure water could only recover the lost permeate flux by 30%, and the decrease of backflushing interval was helpful in improving UF permeate productivity. Chemical cleaning test revealed that the combination of sodium hydroxide and EDTA was an ideal agent for cleaning the fouled membranes.
基金
Mega-Projects of S&T Research for the 10th Five- Year Plan from Ministry of S&T of the People’s Republic of China(2001BA501A02B)
Shenzhen S&T Tri- item Foundation (S040145)
