摘要
通过干酪乳清超滤浓缩试验,研究了膜比阻及结垢层比阻与操作压力的关系,建立了渗透速率与主流液速度、平均操作压力、pH 值以及操作时间的关系的数学模型,并采用稀释过滤方法提高最终产物的蛋白质浓度。结果表明,当操作压力小于0.2 MPa 时,结垢层比阻小于膜自身比阻,而当操作压力大于0.2MPa 时则大于膜自身比阻;压力对渗透速率的影响较强,主流液速度次之;在可能情况下,应尽量选择大的压力和主流液速度;从节能的角度说,超滤优于蒸发法浓缩。
Based on a large quantity of experiments,the relationship between spe- cific resistance of membrane and fouling layer,and the average pressure is stud- ied.Mathematical models are established to describe the relationship between per- meation flux and bulk solution velocity,average pressure,pH value of material and operating time.In addition,diafiltration is used to gain high whey protein concentra- tion.The result shows that specific resistance of the fouling layer is lower than that of the membrane at average pressure below 0.2 MPa and higher than that of mem- brane at average pressure above 0.2 MPa;If condition permits,high average pres- sure and bulk solution velocity are preferred.Ultrafihration can save a large amount of energy compared with evaporation method.
关键词
超滤
乳清
蛋白
渗透速率
ultrafiltration
whey
protein
permeation flux
