Alvarez J A, Zapico C A, Gómez M, Presas J, Soto M
Dept. of Química Física e Enxeñeria Química I, University of A Coruña, A Zapateira s/n, 15071 A Coruña, Galiza, Spain.
Water Sci Technol. 2003;47(12):223-30.
Raw domestic wastewater from the city of Santiago de Compostela (Northwest Spain) was fed into a pilot-scale hydrolytic up flow sludge bed (HUSB) digester with an active volume of 25.5 m3. The total influent chemical oxygen demand (COD) ranged from 360 to 470 mg/l, the influent SS varied from 190 to 370 mg/l, and the temperature was between 17 degrees and 20 degrees C. The organic load rate (OLR) applied increased step by step from 1.2 to 3.9 kgCOD/m3 x d, while the hydraulic retention time (HRT) decreased from 7.1 h to 2.9 h. A high suspended solids (SS) removal of about 82-85% from the influent was reached, most of which (81 to 88%) was eliminated by hydrolysis, while the rest remained in the purge stream. The total COD removal ranged from 46 to 59%. On the other hand, a high acidification of the COD remaining in the effluent was obtained, so the percent COD in the form of volatile fatty acids (VFA(COD)) with respect to total effluent COD was about 43% for the highest HRT applied, and about 27% for the lowest HRT. The soluble to total COD ratio (CODs/CODt) increased from 25-32% for the influent to 71-86% for the effluent. The results obtained confirm the viability and interest of direct anaerobic hydrolytic pre-treatment of domestic wastewater.
来自西班牙西北部圣地亚哥-德孔波斯特拉市的未经处理的生活污水被输送到一个有效容积为25.5立方米的中试规模水解上流式污泥床（HUSB）消化池中。进水总化学需氧量（COD）在360至470毫克/升之间，进水悬浮物（SS）在190至370毫克/升之间，温度在17摄氏度至20摄氏度之间。施加的有机负荷率（OLR）从1.2逐步增加到3.9千克COD/立方米·天，而水力停留时间（HRT）从7.1小时减少到2.9小时。进水悬浮物（SS）的去除率较高，达到约82% - 85%，其中大部分（81%至88%）通过水解被去除，其余部分留在排放流中。总COD去除率在46%至59%之间。另一方面，出水剩余COD的酸化程度较高，因此对于所应用的最高HRT，挥发性脂肪酸形式的COD（VFA(COD)）占总出水COD的百分比约为43%，对于最低HRT则约为27%。可溶性COD与总COD的比率（CODs/CODt）从进水的25% - 32%增加到出水的71% - 86%。所获得的结果证实了生活污水直接厌氧水解预处理的可行性和价值。
