鹽度對厭氧固定化細胞處理酸菜廢水之影響

EFFECT OF SALINITY ON TREATMENT OF PICKLED MUSTARD WASTEWATER USING AnEMMC

劉安琪(An-Chi Liu) ； 周楚洋(Chu-Yang Chou)

《農業機械學刊》 23卷2期 (2014/06) Pp. 1-14

摘要

本研究以醋酸纖維素（cellulose acetate）為固定化材質，包覆厭氧污泥製成固定化細胞（immobilized cells），做為上流式厭氧包埋固定化細胞填充床（up-flow anaerobic entrapped mixed microbial cell packed bed）的介質以處理高鹽度酸菜廢水，並探討鹽度對處理效率之影響。操作過程中，厭氧槽溫度控制在攝氏37±1℃，進流鹽度分別維持在15及26%，總化學需氧量（TCOD）濃度約為15,000及25,000 mg/L，每天進、出流各250 mL，水力停留時間（hydraulic retention time, HRT）為20天，實驗時採26-15-26-15-26-15%鹽度交替試驗，共有6個試程，以S_1-S_6表示，連續操作200天左右，期間觀察pH、產氣量、甲烷產率及有機物的變化情形。結果顯示，整個實驗過程中出流水pH值介於6.3～6.8，在每日進、出流各250 mL、鹽度幾近飽和的26%時，S_1、S_3及S_5試程TCOD之去除率最高可達58%；而鹽度降至15%之S_2、S_4及S_6試程中，TCOD去除率在出流鹽度接近進流鹽度時之區間可穩定達63%；另觀察產氣部份發現，S_2、S_4及S_6試程中甲烷（methane, CH_4）百分比最高可達36%，甲烷產率（methane production rate, MPR）亦可達0.032 L CH_4/L．d。本研究成功找出可明顯產氣之最大鹽耐受度15%，相較於其他試驗（皆低於4%）在鹽度上有明顯的突破，且TCOD去除率最高可達63%，在產氣量、甲烷產率及甲烷百分率方面亦有不錯的表現，最大值分別為0.53 L/d, 0.032 L CH_4/L．d及36%，證明應用上流式厭氧包埋固定化細胞填充床反應槽系統於高鹽度酸菜廢水的處理及產氣研究相當可行。

關鍵字

厭氧消化 ； 固定化細胞 ； 包埋式混合菌種 ； 酸菜廢水 ； 高鹽廢水

並列摘要

Immobilized cells entrapped in anaerobic sludge with cellulose acetate were used as the media for a packed-bed reactor. The objective of this study investigates the feasibility of using these immobilized cells as the media in an up-flow anaerobic entrapped mixed microbial cell (AnEMMC) packed bed reactor system in the treatment of concentrated pickled mustard saline wastewater. A modified up-flow anaerobic reactor was installed and operated at 37±1℃. Influent and effluent was controlled at 250 mL/d, 20-day hydraulic retention time (HRT) and two different types of substrate, raw pickled mustard wastewater (26% salinity) and dilute influent (15% salinity), were maintained at constant total chemical oxygen demand (TCOD) concentrations of 25,000 and 15,000 mg/L during experiment. Totally 6 tests were conducted about 200 days and represented as S_1-S_6. Gas production (GP), pH value, methane content and organic components were monitored during experiment. The results indicated that pH value ranged between 6.3 and 6.8 in all tests. The highest removal efficiency of TCOD in the processes of S_1, S_3 and S_5 was 58% at 26% salinity. As the salinity decreased to 15% in tests of S_2, S_4 and S_6, it was observed that the highest TCOD removal efficiency of 63% could be achieved. Methane contents were high to 36% during these 3 tests, and methane production rate (MPR) was 0.032 L CH_4/L．d. This study successfully identified a maximum salt tolerance of 15% and had an apparent gas production. Compared with other anaerobic processes (all less than 4% salinity) for saline wastewater treatment, a significant breakthrough in salt tolerance was achieved. In summary, the optimal results of TCOD removal efficiency, GP, MPR and methane content obtained were 63%, 0.53 L/d, 0.032 L CH_4/L．d and 36%, respectively. It was proved that the application of the (AnEMMC) packed bed reactor system in treating the concentrate pickled mustard saline wastewater and the production of renewable methane was quite feasible.

並列關鍵字

Anaerobic digestion ； Immobilized cells ； Entrapped mixed microbial cell (EMMC) ； Pickled mustard wastewater ； High salinity wastewater