自來水廠淨水污泥壓濾式脫水之研究

Study on Slurry Dewatering with Filter Press in Water Treatment Plant

游乙剛(Yi-Kang Yu)

指導教授 ： 劉敏信

朝陽科技大學/理工學院/環境工程與管理系/碩士(2012年)

摘要

本研究針對台灣自來水公司豐原給水廠廢水系統中之淨水污泥壓濾脫水效能進行評估，並組裝一試驗型壓濾式脫水機，利用不同透氣性聚丙烯濾布當進料污泥濃度分別為5%、10%、15%與37.3%（實場污泥濃度）條件下，改變壓濾時間分別為30 min、60 min、90 min，板框濾室厚度設定為2.5 cm、3.0 cm、3.5 cm、4.0 cm、4.5 cm，調整進料壓力在5.5 kg/cm2進行批次式進料脫水實驗，並探討卸料後污泥餅之重量、含水率及濾液之變化情形，進一步探討壓濾式脫水機參數設定對壓密泥餅產出效率與含水率之影響。
由第一階段實驗結果，另設定一濾板濾室厚度3.5 cm進行兩種不同透氣性濾布進料壓力試驗，調整空壓機壓力分別為4 kg/cm2、5.5 kg/cm2、7 kg/cm2進行連續式實場污泥濃度29.94%進料脫水並探討壓力高低對卸料後污泥餅含水率與重量之變化情形。
第一階段試驗結果發現，低污泥濃度5%、10% 、15%進料，使用薄濾室2.5 cm及壓濾時間設定60 min有最佳之脫水提升效率；而高污泥濃度37.3%進料下，選擇厚濾室4.5 cm及壓濾時間設定30 min即可產出低含水率及高產量之泥餅。
選用兩種不同透氣性聚丙烯濾布進行壓濾試驗，並彙整濾布電子顯微鏡放大400倍圖及取樣第一批1000 L脫水後之濾液進行雷射粒徑分析結果得知，大孔隙低透氣性濾布比小孔隙高透氣性濾布有較佳的脫水提升效率。
　　第二階段進料壓力試驗得知，當壓力從4 kg/cm2提高至7 kg/cm2壓濾時，有助於增加污泥餅重量及降低含水率之效果。

關鍵字

含水率 ； 污泥餅 ； 壓力 ； 聚丙烯濾布 ； 壓濾式脫水 ； 淨水污泥

並列摘要

The study examines the effectiveness of sludge dewatering using filter presses in Feng Yuan Purification Plant of Taiwan Water Corporation. By installing an experimental filter press and using polypropylene filters, the study tries to remove the liquid from liquid-solid sludge containing 5%, 10%, 15% and 37.3% solids for 30, 60 and 90 minutes by batch conditioning. The pressure is set at 5.5 kg/cm2 with the voids between plates(filter chambers) measuring 2.5cm, 3.0 cm, 3.5cm, 4.0 cm and 4.5 cm respectively. The study observes the filtrate, the weight and moisture content of each filter cake to investigate the influence of parameters of a filter press on the production and the moisture content of filter cakes. Based on the results of the first phase of the experiment, another void between plates(filter chambers) measuring 3.5 cm is designed for pressure tests with fabric filters of low permeability and high permeability. The pressure is set at 4 kg/cm2, 5.5 kg/cm2, and 7 kg/cm2 respectively to dewater liquid-solid sludge containing 29.94% solids by continuous feeding for the observation of the influence of pressure on the weight and moisture content of filter cakes.
The first phase of the experiment indicates that a narrow void between plates(filter chamber) measuring 2.5cm and the pressure setting at 60 minutes give the best dewatering efficiency for sludge containing a lower percentage of solids of 5%, 10%, 15%. On the other hand, when sludge contains solids up to 37.3%, good filter cakes with low moisture content can be produced by a wide void measuring 4.5 cm and the pressure setting of 30 min.
We conduct pressure tests with polypropylene filters with different permeability and summarize views of the filters under the microscope at 400 times of magnification. Take 1000 L of filtrate from the first batch of condition for particle size distribution by LASER diffraction. The results show that polypropylene filters with large mesh size and low permeability facilitate better dewatering than those with small mesh size and high permeability.
The second phase pressure tests indicates that the increased pressure from 4 kg/cm2 to 7 kg/cm2 help add the weight and reduce the moisture content of filter cakes.

並列關鍵字

moisture content ； press ； filter cake ； filter press dewatering ； polypropylene filters ； sludge

參考文獻

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