中文摘要 近年來，廢水處理技術的開發，廢水系統排入前提供有效的去除氮和碳。近來膜生物反應器（ MBR ）各種優點包含去除含碳化合物和氮，如今由於營養物去除過程中的優勢，讓生物脫氮的MBR系統的各種配置和預脫硝成為優勢。 在這項研究中，針對化學需氧量總氮比（ COD / TN ），再循環率和污泥停留時間（SRT ）的效果進行研究，利用實驗室規模生物載體-好氧膜生物反應器（ A / O ）系統去除生活合成廢水COD和氮。該系統進行了300天左右，根據不同的COD / TN比，再循環率和SRT，分成四個實驗階段。為評估碳源的影響、污泥停留時間對污泥生長的效果研究，將COD / TN比從3到7的調整，通過添加額外的碳源。再調整循環比例，內部循環流量改為從2Q到2.5Q 。 SRT的變化，從20天到10天。 結果表明，最高去除率， COD ， NH4 + - N ， TN為99.9 ％ ，100％和93 ％，最佳操作條件為2.5Q再循環率， COD / TN比為7:3 ，SRT為20天。進水COD / TN比，再循環率和SRT對COD及脫氮性能的影響顯著。在最佳條件下，該系統達到完整的硝化和脫硝作用。在優化條件下無氧池和MBR生物量增加。因此該系統可為導致去除效率高的微生物增長提供了良好的條件。本研究的結果顯示TN以硝酸鹽的形式存在過濾液中，其中的最低水平是3毫克/升。表示無氧載體-好氧膜生物反應器可以取代A2O系統，有效處理含氮廢水。 ABSTRACTIn recent years, wastewater treatment technologies are developed to provide effective nitrogen and carbon removal before discharge into water system. Membrane bioreactor (MBR) has lately been the process of interest for carbonaceous compound and nutrient removal due to various advantages. Nowadays, biological nitrogen removal has been achieved by various configurations of MBR systems and pre-denitrification has always been the preferred configuration.In this study, the effect of chemical oxygen demand to total nitrogen (COD/TN) ratio, recirculation rate and solid retention time (SRT) were investigated in the performance of a laboratory scale biocarrier-aerobic MBR (A/O) system on COD and nitrogen removals from synthetic domestic wastewater. The system was conducted for around 300 days with four experimental stages under different COD/TN ratio, recirculation rate and SRT. To evaluate the effect of carbon source addition, the COD/TN ratio was adjusted from 3 to 7 by adding extra carbon source. For recirculation ratio adjustment, internal recycle flow rate was changed from 2Q to 2.5Q. SRT was varied from 20 days to 10 days to study the effect of retention time on bacteria growth.The results illustrated that the highest removal efficiencies of COD, NH4+-N and TN of 99.9%, 100% and 93%, respectively, were achieved when the A/O MBR system was operated under optimal condition of 2.5Q recirculation rate, COD/TN ratio of 7, and SRT of 20 days. Influent COD/TN ratio, recirculation rate and SRT influenced the COD and nitrogen removal performance significantly. Under optimal condition, the system reached complete nitrification and high denitrification. Addition of carbon source, recirculation rate and SRT correlated with biomass concentration and the removal capacity. Biomass in anoxic tank and MBR increased under optimum condition. It indicated that the system could provide good condition for biomass growth resulting in high removal efficiency. The results of this study also showed that TN existed in the permeate by the form of nitrate only wherein the lowest level was 3 mg/L. It indicated that this biocarrier anoxic-oxic system can replace an anaerobic-oxic system for high nitrogen and COD removals from wastewater.
