Biological treatment of meat industry wastewater

The work aimed to determine the effectiveness of the treatment of wastewater generated by the meat industry in a hybrid system combining biological methods of activated sludge (in an SBR reactor) and reverse osmosis. The tests carried out on the wastewater from the meat processing plant Uni-Lang in Wrzosowa showed that the biological treatment resulted in sufficient removal of contaminants from the wastewater, which consequently could be discharged into receiving water. In order to make it possible for the wastewater to be reused in the production cycle, it was additionally treated with reverse osmosis. The research was described mathematically by the program MATLAB using artificial neural networks. The program enables a prediction of the results for the treatment of wastewater over a range of tested values.

Wastewater from the meat industry is very difficult to purify due to its specific characteristics; irregular scatter; and considerable amounts of organic, mineral and biogenic matter. This type of wastewater can be treated biologically by means of activated sludge applying a low sludge loading of 0.15 COD/g dry wt. sludge ×d, aeration intensity of 840 dm3 air/h, constant sludge concentration in the chamber of 5 g/dm3, residence time of wastewater in the bioreactor of 12 h and a ratio of the stirring time to the sum of the stirring and aeration times of 0.3. The wastewater thus treated meets the requirements of the Regulations of the Ministry of Environmental Protection, Natural Resources and Forestry, dated 5 November 1991, and can be discharged into receiving water.