| 摘要 |
PURPOSE:To efficiently concentrate the culture solution without causing reduction of water permeation rate with the elapse of time by filtering a culture solution of unicellular algae in cross flow using an ultrafilter module of hollow yarn having a given fractional molecular weight range while periodically washing in an under flow. CONSTITUTION:The above-mentioned culture solution in a culture tank 1 is concentrated by cross flow filtrating using an ultrafilter (UF) module 3 of hollow yarn having 10,000-100,000 fractional molecular weight. During the filtration, the UF module 3 is automatically washed in an under flow by closing an automatic valve (AV) 4 for 30-60 seconds at 15-60 minutes intervals in the operation of concentration. In the automatic washing in an under flow; the surface of the filter can be efficiently washed by inverting direction of passage of stock solution at every time. Consequently, for example, the culture solution having about 20,000,000 cells/ml cultured Chlorella concentration can be concentrated at treatment rate of >=60l/m<2> Hr average permeation rate based on 2,000,000,000 cells/ml film area. |
