污水處理外文翻譯---絮凝污泥性質(zhì)和廢水處理的影響

1、<p>　　絮凝：污泥性質(zhì)和廢水處理的影響</p><p><b>　　摘要</b></p><p>　　進行研究，以確定在激活的絮凝作用污泥單元過程。實驗室和完整的大型研究顯示，絮凝最重要的，在于確定沉淀，脫水，污水和消化污泥特性（活性污泥屬性），并可能涉及到的所有進程的功能是至關(guān)重要的。在這些研究中，結(jié)果表明，二價陽離子，如鈣和鎂改善活性污泥的性質(zhì)，而單

2、價陽離子如如鈉，鉀和銨離子，不利于這些屬性。 “二價陽離子通過銜接機制，促進負責(zé)絮凝帶負電荷的生物大分子（主要是蛋白質(zhì)和多糖）。結(jié)果發(fā)現(xiàn)，氧化鐵起著重大作用，在活性污泥的絮凝和決心通過鐵和生物大分子之間的表面相互作用的性質(zhì)。氧化鐵有效地消除從凝固的膠體溶液聚合物和空調(diào)的研究。這項研究包括鉀的實驗評估影響沉降和脫水性能和銨離子，鎂的影響沉降性能;影響鈉，鉀，鈣和鎂的廢水質(zhì)量;固體停留時間，對出水水質(zhì)的影響;絮狀物評估在有氧和高溫消化的屬性

3、。一個絮狀物模型中提出鈣，鎂，鐵絮凝的功能是很重要曝氣池，沉淀池，脫水設(shè)備和好氧或厭氧沼氣池。</p><p>　　結(jié)果表明，活性污泥絮狀物性能的影響廢水處理效率。</p><p>　　關(guān)鍵詞：陽離子，活性污泥，沉淀，脫水，鎂，銨。</p><p><b>　　前言</b></p><p>　　活性污泥是由微生物財團和胞

4、外聚合物和二價陽離子（手冢，1969年形成了矩陣一起舉行的有機和無機粒子;諾瓦克和豪根，1981年埃里克森和ALM，1991; Bruus等，1992;希金斯和諾瓦克，1997年，B）。 bruus等人。 （1992年）和希金斯和諾瓦克（1997年b）表明，多余的單價陽離子可引起中絮狀物的惡化結(jié)構(gòu)和沉降性能。觀察與二價陽離子的增加沉降性能的改善。</p><p>　　許多工業(yè)系統(tǒng)需要高純度的進水。因此，除了規(guī)定的

5、化學(xué)品在工業(yè)過程和廢水預(yù)處理的廢水進入激活污泥盆地的陽離子組成。這些廢水通常會在一些陽離子缺陷，將包含他人的過多。單價離子的增加導(dǎo)致活性污泥脫水性能的惡化，而二價離子的增加已被證明可以改善活性污泥脫水性能希金斯和諾瓦克，1997，（二）已被觀察到。這些意見進行了實驗室和工業(yè)系統(tǒng)中活性污泥絮體。希金斯和諾瓦克（1997年b）評估從七個工業(yè)設(shè)施的陽離子和發(fā)現(xiàn)，時的上chargeequivalent的基礎(chǔ)上的單價超過二價陽離子比（M / D）

6、2，在脫水性能（具體到過濾阻力）發(fā)生惡化。最經(jīng)常發(fā)現(xiàn)添加燒堿的pH值控制在行業(yè)的高M/ D比值的相關(guān)問題。因此，鈉離子是游離在這些系統(tǒng)中的單價離子輸入。</p><p>　　本研究的目的是評估nonfilamentous沉降和脫水的問題進行鑒定的潛力，通過篩選陽離子，到達實驗室或田間試驗的策略，找出并解決相關(guān)的問題（S）。</p><p>　　工業(yè)體系研究含有高濃度的鈉離子（平均為2000

7、毫克/升）加入氫氧化鈉預(yù)處理步驟，以防止醋酸的揮發(fā)。廢物流中的主要成分是醋酸。進水COD為10000毫克/升的順序?；钚晕勰嗟膒H值8.8。工業(yè)廢水處理系統(tǒng)被發(fā)現(xiàn)有極端貧困的沉降和脫水性能由于高濃度的鈉離子。最初進行化驗，以評估為二價陽離子的可能的應(yīng)用領(lǐng)域，以實現(xiàn)較低的M / D比值，其次是活性污泥性質(zhì)的每周監(jiān)測的田間試驗的戰(zhàn)略。提出了短期和長期的解決方案。</p><p><b>　　結(jié)論1</

8、b></p><p>　　離子是直接關(guān)系到沉降和脫水性能的變化。該實驗室的研究是一個有效的田間試驗的序幕。實驗室可處理的研究表明鈣此外田間試驗的不適應(yīng)。進一步的實驗室研究表明，鎂會是一個合適的二價陽離子替代。田間試驗表明，在絮狀密度增加鎂離子的改善。前一個時間差可以預(yù)計實現(xiàn)沉降性能的改進。雖然陽離子交換可能發(fā)生，可能需要更換的污泥絮體的完整的二價金屬離子被完全納入到污泥絮。</p><p

9、>　　鎂離子提高脫水性能的實驗研究，在更大程度上比在實地試驗，可能是由于在實驗室研究中使用的二價離子濃度較高的表現(xiàn)。田間試驗與增長中的可溶性銨離子的脫水性能?？磥?，銨離子活性污泥絮體在類似的方式，以鈉離子相互作用，導(dǎo)致可溶性蛋白的釋放和脫水性能惡化。復(fù)雜的變化，同時在幾個陽離子可使其具有挑戰(zhàn)性的隔離沉降和脫水性能變化的原因?？紤]對他們的影響力，解決anddewatering屬性時，需要考慮不同的陽離子和絮狀物（成絮狀物的摻入陽離子

10、）之間的互動和彼此之間（陽離子交換）。硫酸鎂除了被證明是非常有益的沉降性能改善。如果需要進一步改善，長期戰(zhàn)略是必不可少的。</p><p>　　對于工業(yè)設(shè)施，它可能是有用的，以探索其他替代品的pH值控制。在曝氣池硝化的成就可能會進一步改善活性污泥絮體的屬性。硝化活性污泥性能的影響，需要進一步探索。</p><p><b>　　結(jié)論2</b></p>&l

11、t;p>　　實驗室和現(xiàn)場進行了研究，評估調(diào)節(jié)選項ATAD污泥脫水。本研究的目的是探討機會，以減少化學(xué)空調(diào)費用。研究，進行陽離子聚合物和無機調(diào)理組合（三氯化鐵或明礬）陽離子聚合物。</p><p>　　這項研究表明，如氯化鐵和明礬等無機空調(diào)非常有效地降低空調(diào)的化學(xué)要求，從而減少經(jīng)營成本，為ATADs。無機空調(diào)消除陰離子biocolloids有效。之前實現(xiàn)電荷中去除的陰離子biocolloids的發(fā)生。去除這些

12、陰離子biocolloids的可能是通過鐵羥基礦物相關(guān)降水量為混凝研究中觀察到。與陽離子聚合物的調(diào)理機制是通過電荷中和。前凝血與無機調(diào)理污泥將減少溶液中的負電荷，從而消除了一些陽離子聚合物的需求。</p><p>　　不同的機制導(dǎo)致不同的空調(diào)需求。氯化鐵和明礬是更有效地消除較大規(guī)模的蛋白質(zhì)和多糖分子（大于30K）。無機混凝劑，也更有效的生物聚合物和化學(xué)需氧量釋放更大。應(yīng)考慮使用無機化學(xué)混凝劑，在消化過程中釋放大量

13、的蛋白質(zhì)，多糖和COD時發(fā)生。</p><p>　　其次是用明礬和陽離子高分子絮凝劑大大降低空調(diào)化學(xué)學(xué)院站成本的空調(diào)溫曝氣相結(jié)合。成本相近或低于，需要溫厭氧消化。</p><p>　　濾液回收化學(xué)需氧量明顯減少，廠內(nèi)發(fā)泡大學(xué)是很大程度上消除了采用組合的中溫曝氣和利用明礬。</p><p>　　BIOFLOCCULATION: IMPLICATIONS FOR ACT

14、IVATED SLUDGE PROPERTIES AND WASTEWATER TREATMENT</p><p><b>　　ABSTRACT</b></p><p>　　Studies were conducted to determine the role of bioflocculation in the activated.sludge unit proce

15、sses. Laboratory and full-scale studies revealed that bioflocculation is important in determining settling, dewatering, effluent and digested sludge properties(activated sludge properties) and may be vital to the functio

16、n of all processes related to the above properties. In these studies, it was shown that divalent cations such as calcium and magnesium improved activated sludge properties, whereas m</p><p>　　It is shown tha

17、t activated sludge floc properties affect wastewater treatment efficiency.</p><p>　　Keywords：Cation, activated sludge, settling, dewatering, magnesium, ammonium.</p><p>　　Introduction</p>

18、<p>　　Activated sludge is comprised of microbial consortiums and organic and inorganic particles held together in a matrix formed by exocellular polymers and divalent cations (Tezuka, 1969; Novak and Haugan, 1981;

19、Eriksson and Alm, 1991; Bruus et al., 1992; Higgins and Novak, 1997a, b). Bruus et al. (1992) and Higgins and Novak</p><p>　　(1997b) have shown that excess monovalent cations can cause a deterioration in flo

20、c</p><p>　　structure and settling properties. Improvements in settling properties were observed with an increase in divalent cations.</p><p>　　Many industrial systems require influent water of h

21、igh purity. Therefore, the addition of chemicals during the industrial process and wastewater pretreatment dictate the cationic composition of the wastewater entering the activated sludge basins. Often these wastewaters

22、will be deficient in some cations and will contain an overabundance of others. An increase in monovalent ions has been observed to cause a deterioration in dewatering properties in activated sludge, whereas an increase i

23、n divalen</p><p>　　The purpose of this study was to evaluate the potential for identification of nonfilamentous settling and dewatering problems through screening of cations, to arrive at a strategy for labo

24、ratory or field trials, and to identify and address the associated problem(s).</p><p>　　The industrial system studied contained a high concentration of sodium ions(average of 2,000 mg/l) added as sodium hydr

25、oxide in the pretreatment step to prevent volatilization of acetic acid. The major component in the waste stream was acetic acid. The influent COD was in the order of 10,000 mg/l. The activated sludge had a pH of 8.8. Th

26、e industrial wastewater treatment system was found to have extremely poor settling and dewatering properties due to a high concentration of sodium ions. Laborato</p><p>　　Conclusions1</p><p>　　C

27、ations were directly related to changes in settling and dewatering properties. The laboratory study was an effective prelude to field trials. The laboratory treatability study indicated the unsuitability of calcium addit

28、ion for the field trial. The laboratory research further showed that magnesium would be a suitable divalent cation alternative. Field trials demonstrated an improvement in floc density associated with an increase in magn

29、esium ions. A time lag could be anticipated prior to achiev</p><p>　　Magnesium ions improved dewatering properties in the laboratory study to a greater extent than demonstrated in the field trials, probably

30、due to the higher concentration of the divalent ion used in the laboratory study. The field trials linked</p><p>　　dewatering properties to an increase in the soluble ammonium ions. It appears that ammonium

31、ions interact with activated sludge flocs in a manner similar to sodium ions, causing a release in soluble proteins and a deterioration in dewatering properties.</p><p>　　Complex variations in several cation

32、s simultaneously may make it challenging to isolate the cause for changes in settling and dewatering properties. Interaction between different cations and the floc (cation incorporation into the floc) and amongst themsel

33、ves (cation exchange) need to be taken into account when considering their influence on settling anddewatering properties. The addition of magnesium sulfate proved to be extremely beneficial in improving settling propert

34、ies. If further improvem</p><p>　　For the industrial facility, it may be useful to explore other alternatives for pH control. Achievement of nitrification in the aeration basin may further ameliorate activat

35、ed sludge floc properties. The effect of nitrification on activated sludge properties require further exploration.</p><p>　　Conclusions2</p><p>　　Laboratory and field studies were conducted to e

36、valuate the conditioning options</p><p>　　for the dewatering of ATAD biosolids. The objective of this study was to investigate opportunities to reduce chemical conditioning costs. Studies were conducted usin

37、g cationic polymer and a combination of inorganic conditioners (ferric chloride or alum)and cationic polymer.</p><p>　　This study indicated that inorganic conditioners such as ferric chloride and alum</p&

38、gt;<p>　　were very effective in reducing conditioning chemical requirements, thereby reducing</p><p>　　operation costs, for ATADs. The inorganic conditioners were effective in removing anionic biocoll

39、oids. Removal of the anionic biocolloids occurred prior to achieving charge neutralization. The removal of these anionic biocolloids may be through ferric-</p><p>　　hydroxy mineral associated precipitation a

40、s observed in the coagulation study. The conditioning mechanisms associated with cationic polymer is through charge neutralization. Pre-coagulation of biosolids with inorganic conditioners will reduce the negative charge

41、s in solution, thereby eliminating some of the cationic polymer demand.</p><p>　　The different mechanisms lead to different conditioning requirements. Ferric chloride and alum were more effective in removing

42、 larger sized protein and polysaccharide molecules (greater than 30K). The inorganic coagulants were also more effective then the biopolymer and COD release was greater. The use of inorganic chemical coagulants should be

43、 considered when large release of protein, polysaccharide and COD occur during the digestion process.</p><p>　　A combination of mesophilic aeration followed by conditioning with alum and cationic polymer flo

44、cculant greatly reduced conditioning chemical costs at College Station. The costs were similar to or lower than that required for mesophilic anaerobic</p><p>　　digestion.</p><p>　　Filtrate recyc