Treatment of Wheat Starch Waste Water Using a Fixed-Bed anaerobic Reactor

Although waste water from the manufacture of wheat starch is usually treated aerobiologically mainly using the activated sludge process, both saving in the energy used for aeration and achiev-ing a decrease in excess sludge generation remain serious problem from an economical point of view. On the other hand, anaerobic digestion process, having the advantage of economics, has been seemed to be practical if the hold-up of biomass in the reactor is improved. Therefore, we succeeded in developing the commercial size of fixed-bed anaerobic reactor with high density of biomass in the packed media, which is able to decompose the wheat starch waste water more economically and stably than the conventional activated sludge process. Through over almost four years operation of actual plant we studied its performance and process conditions.