Reimann W
Institute of Agricultural Engineering ATB, Max-Eyth-Allee 100, D-14469 Potsdam-Bornim, Germany.
Water Sci Technol. 2002;46(11-12):177-82.
The use of membrane separation technology, such as ultrafiltration (UF) and subsequent reverse osmosis (RO), for purifying different types of low-contaminated wash water of carrots (COD = 1,314 mg/l) and wash water of different kinds of vegetables (COD = 2,280 mg/l) was investigated on a pilot scale to determine its suitability for reuse in the process. In both membrane processes, UF and RO, the permeate flux first decreased with increasing fouling (deposition of organic and inorganic substances on the membrane surface and in its pores). After that the membrane permeability (permeate flux) and selectivity (rejection of COD) remained constant on a stable level in spite of a concentration with a volumetric concentration factor of up to 39. The tests showed that water can be obtained with a quality complying with the German regulations by applying a process combination of UF and RO. It was found that the membranes gave a 5-log reduction for total bacteria, and no coliform bacteria were present in the permeate after RO. Using UF and RO, part of the wastewater can be recovered for reuse in the process if drinking water is used for the last step of vegetable washing.
在中试规模下，研究了使用膜分离技术，如超滤（UF）和后续的反渗透（RO），来净化不同类型的低污染胡萝卜洗涤水（化学需氧量[COD]=1314毫克/升）和不同种类蔬菜的洗涤水（COD=2280毫克/升），以确定其在该过程中再利用的适用性。在超滤和反渗透这两种膜过程中，随着污垢的增加（有机和无机物质在膜表面及其孔隙中的沉积），渗透通量首先会下降。在此之后，尽管体积浓缩系数高达39进行了浓缩，但膜的渗透率（渗透通量）和选择性（对COD的截留率）仍保持在稳定水平。测试表明，通过采用超滤和反渗透的工艺组合，可以获得符合德国法规质量要求的水。结果发现，这些膜对总细菌有5个对数级的减少，反渗透后的渗透液中不存在大肠菌群。如果在蔬菜洗涤的最后一步使用饮用水，利用超滤和反渗透技术，部分废水可以回收用于该过程的再利用。
