Abstract: Food waste pretreatment slurry can theoretically be used as a carbon source in the biological denitrification process of wastewater treatment due to its high COD concentration. However, direct dosing of food waste pretreatment slurry in these processes was limited as its high SS content could easily lead to membrane fouling in follow-up processes. In order to solve this problem, a new type of dish centrifuge was used to treat food waste pretreatment slurry, and the treatment performance was analyzed under different feed temperatures, nozzle pore sizes and slag discharge intervals. The results showed that the optimal operating parameters were under the temperature of 60 ℃, the nozzle aperture of 0.6 mm and the slag discharge interval of 5 minutes, with a suspended solids removal rate of 85.95%. Engineering application results showed that food waste-originated carbon source could partially replace commercial carbon source in biochemical treatment process. While the equivalent ratio of food waste-originated carbon source to methanol was about 24∶1, and methanol dosage could be reduced by up to 30%.

Key words: food waste, carbon sources, biochemical treatment, disc separator, resource utilization