Báo cáo khoa học: Xử lý đồng thời chất hữu cơ và nitơ trong nước thải chăn nuôi lợn bằng phương pháp SBR - Ảnh hưởng của chế độ cấp nước thải giới thiệu về quá trình SBR, hiệu suất xử lý thí nghiệm lý thuyết của quá trình SBR hai chu trình thiếu – hiếu khí cấp nước hai lần, nguyên liệu và phương pháp, kết quả và thảo luận. | Simultaneous removal of organic and nitrogen matters from piggery wastewater by Sequencing Batch Reactor (SBR) process integrated with double anoxic – oxic cycles and two-step feeding was investigated. Anaerobically digested piggery wastewater was fed stepwise into the reactor during the anoxic stages with three different feeding ratios (ratio of wastewater volume of the first feeding to the total feeding volume in each batch) of 1/2, 2/3 and 3/4. Effects of these ratios on removal of chemical oxygen demand (COD), ammonium and total nitrogen (T-N) were experimentally determined and compared with those obtained in the case of single feeding mode. Theoretical T-N removal efficiencies were also described and compared with the experimental ones. The results indicated that step feeding is a means for enhancing T-N removal. It was also shown that when increasing the feeding ratio, T-N removal efficiency increased in the first instance, however then decreased when the ratio reaching a given value. Experimental T-N removal efficiencies at three investigated feeding ratios were rather high, in which the highest was obtained at the ratio of 2/3, in the range of 85 – 90 %. The experimental T-N removal efficiencies at the low feeding ratios of 1/2 and 2/3 were in the same level with the theoretical ones. COD removal efficiencies in two-step feeding mode were also rather high, 85 – 90 % at the ratio of 2/3, close to that obtained in the single feeding mode. High values of COD and T-N loads were also achieved,
