化學調理影響廢棄活性污泥特性之研究

Abstract

活性污泥中含有高濃度的氮磷及致病菌而且脫水性差，因此本研究利用前 處理厭氧消化及化學調理方式用以改變污泥特性，以期望達到降低氮磷含 量、減少致病菌，改善脫水性的目的。本研究中使用金屬鹽類、有機聚合 物進行污泥化學調理研究，另外更進一步利用經過鹼前處理的污泥進行厭 氧消化反應的研究，探討不同處理方式對污泥中氮磷含量、致病菌數目及 脫水性變化之影響。研究結果顯示，廢棄活性污泥進行化學調理操作之各 項因子諸如：攪拌時間、攪拌速度、pH值範圍、調理劑加藥量及調理劑種 類等均會影響其處理效果，實驗過程中分別針對上述因子進行探討，得知 最佳調理程序為：在200rpm快混程序中先加入400mg/L結晶氯化鐵攪拌一 分鐘後加入20mg/L T-3086攪拌三分鐘，接著進行30rpm慢混程序攪拌十分 鐘，發現污泥的脫水性及沉降性有明顯地改善，並且能夠去除75%左右的 溶解性磷，但是對於有機氮之去除效果不佳。另外廢棄活性污泥經由鹼前 處理後厭氣消化後結果得知，污泥中的溶解性磷、有機氮及致病菌數目之 去除及其脫水性均隨著水力停留時間增長而有明顯改善，但是未經鹼前處 理過的廢棄活性污泥若經厭氧消化後，處理結果剛好相反。 The present paper is an attempt to lay the experimental processes based on alkaline pretreatment anaerobic digestion and chemical conditioning to alternate characteristics of sludge, eliminate the quantities contents of N、P、microbial, as well as improve dewaterability. In this study , inorganic salts and organic polymer are used to conditioning sludge, in addition , the sludge is also be alkaline pretreatment and take the reaction of anaerobic digestion. The main purpose of this study is to investigate different methods in which the contents of N、P and the number of microbial well as the alternation of dewaterability are considered. The results indicated that several perimeters of the procedure such as mixing time、mixing speed、pH value、the amount and kinds of chemical conditioners , are significant factors of this processes. The optimal procedure is the following：400mg/L crystal FeCl3 was added in the beginning and mixed for one minute , and then 20mg/L T-3086 was added and mixed for four minutes of under the condition of rapid-mixing of 200 rpm , respectively. Finally , the processes was mixed for ten minutes under the condition of slow-mixing operation. We find 75% dissolved phosphorus can be removed , but organic nitrogenous removal is significant. Otherwise , high HRT undergone the treatment of alkaline pretreatment enhances dewaterability and reduces dissolved phosphorus, organic nitrogenous and microbial contents.