本研究係利用循序批分式結合薄膜生物反應槽SBMBR (Sequencing Batch Membrane Bioreactor,SBMBR),針對目前國內室外養殖水進行處理,在固定污泥停留時間(Sludge Retention Time,SRT)20天和水力停留時間(Hydraulic Retention Time,HRT)6.8小時,而改變操作模式。評估本系統在本土環境條件下之去除效果,以及探討處理過程中反應槽微生物濃度變化和出流水質變化的情形。
實驗結果顯示,試程一和試程二反應槽之MLSS濃度為1564mg/L和1892mg/L,而出流水之SS幾乎趨近於零。COD處理成效方面:試程一進流水約280mg/L,出流水約60mg/L可達行政院環保署水產養殖放流水標準100mg/L以下,去除率74%,試程二進流水約190mg/L,出流水約30mg/L,去除率達87%。BOD5方面:進流水隨實際室外養殖池投料和進水之增減而變動,試程一約70mg/L左右,試程二約在80-90mg/L之間,出流水都在20mg/L以下,去除率試程一77%,試程二可達84%。濁度方面:兩個試程出流水都低於2NTU,符合各項雜用水標準。
食微比和體積負荷方面:試程一和試程二食微比(BOD5)分別為0.15kgBOD5/kgMLVSS-day和0.16kgBOD5/kgMLVSS-day,皆略小於傳統活性污泥程序食微比(0.2-0.4kgBOD5/kgMLVSS-day),體積負荷(BOD5)分別為0.11kgBOD5/m3-day和0.24kgBOD5/m3-day,皆略小於傳統活性污泥程序體積負荷(0.3-0.6kgBOD5/m3-day)。
氮系物種質量平衡方面:試程一的氨氮和有機氮各降19%和15%,而亞硝酸氮和硝酸氮略微上升各3%,試程一的出流水,NH4+-N、NO2--N和NO3--N都有些微累積現象,因此試程一的硝化和脫硝效果較不如預期。試程二的氨氮、有機氮、亞硝酸氮和硝酸氮各降16.5%、52%、6.9%和0.5%,試程二的出流水,NH4+-N、NO2--N和NO3--N幾乎都可完全去除,相較於試程一,試程二有較佳的處理效果。
由本研究結果得知,利用SBMBR系統對於目前國內室外養殖水的處理,出流水的pH值對蝦的生長非常有利,同時第二試程的NH4+-N和NO3--N都有很好的處理效果,可做為養殖循環水回收再利用的參考。 This research is to study the performance of Sequencing Batch Membrane Bioreactor (SBMBR) for the improvement of outdoor aquaculture recycling water quality. Sludge retention time (SRT) and hydraulic retention time (HRT) were set at 20 days and 6.8 hours respectively. Two different operation modes were adopted to assess the treatment performance of the system, including the water quality of effluent and the concentration of activated sludge.
The results of this experiment showed that the MLSS concentration is 1564mg/L and 1892mg/L in run 1 and run 2. No ss is detected in the effluent. As for run 1 the removal efficiency of COD、BOD5 and Trubidity were 74%、77% and 97% respectively.
The resultes showed that the recycling water quality can be improved by different operation mode. After shifting the time interval of aerobic-settling-anaerobic operation, the removals of COD、BOD5 and Trubidity were 87%、84% and 98% respectively. These values met the aquaculture reuse standards of E. P. A., R. O. C.
The F/M ratio and the volumetric loading of this study were lower than these values of traditional AS treatment system. AS for run l and run 2 were 0.15kgBOD5/kgMLVSS-day、0.16kgBOD5/kgMLVSS-day、0.11kgBOD5/m3-day and 0.24kgBOD5/m3-day respectively.
For mass balance of nitrogen, the NH4+-N and Org.-N were 19 and 15% reduce. But both the NO2--N and NO3—N were 3% increase. Comparatively, the NH4+-N、NO2--N and NO3--N concentration of the effluent in run 1 were not removal completely. So the nitrification and the denitrification were far from ideal. However almost completely in run 2, the NH4+-N、Org.-N、NO2--N and NO3--N were 16.5、52、6.9and 0.5% reduce respectively.
The quality of aquaculture recycling water treated by SBMBR is acceptable. The bioreactor is recommended for water reuse in aquaculture.