Anaerobic treatment of wheat stillage

Wheat stillage was treated in anaerobic one- and two-stage laboratory model. Work presented has showed very good anaerobic biodegradability of this material. From a developed laboratory model it was concluded that a two-stage anaerobic technology with previous acidification is not necessary in anaerobic treatment of wheat stillage. However, it could be stated that acidification may help to stability at the start-up of the process. Various parameters were measured in the laboratory model. Organic loading rate was 11.6 kg m(-3) d(-1), hydraulic retention time was 9.25 d, COD efficiency removal was more than 90%, excess sludge production-was 0.07-0.09 kg per kg loaded COD, and methane yield was 0.225 m(3) per kg loaded COD. Because sludge water at the amount similar than volume of the treated stillage is a potential pollutant, both from point of view of organic pollution and content of nitrogen and phosphorus, it needs to be taken into account. in proposing technology for anaerobic treatment of wheat stillage.