外文翻譯-- 在a2o工藝中污水組成對(duì)于脫氮除磷的影響以及控制

1、<p>　　中文3700字，2100英文單詞，10500英文字符</p><p>　　文獻(xiàn)出處：Wang X, Peng Y, Wang S, et al. Influence of wastewater composition on nitrogen and phosphorus removal and process control in A2O process.[J]. Bioprocess &a

2、mp; Biosystems Engineering, 2006, 28(6):397-404.</p><p>　　Influence of wastewater composition on nitrogen and phosphorus removal and process control in A2O process</p><p>　　X Wang ， Y

3、Peng ， S Wang ， J Fan ， X Cao</p><p><b>　　Abstract </b></p><p>　　A bench-scale anaerobic–anoxic–oxic (A2O) bioreactor with steady denitrifying phosphoru

4、s removal performance was tested to determine the influence of influent C/N ratio (SCOD/TN) and C/P ratio (SCOD/TP) on biological nutrient removal for treating synthetic brewage wastewater; meanwhile, the spatial profile

5、s of DO, pH and ORP sensors in such systems were investigated. The results showed that influent C/N ratio had significant effect on the TN, TP removal efficiencies and the ratio of anoxic to ae</p><p>　　KEY

6、 WORDS: A2O process,C/N ratio ,C/P ratio,DO,PH,ORP</p><p>　　Experimental procedures </p><p>　　Synthetic brewery wastewater used in this study contained (per liter): brewage (ethanol content 3.5%

7、) 2.8–3.4 mL; NH4Cl 0.20–0.3 g; KH2PO4 0.02–0.08 g;MgSO47H2O 0.05 g; NaHCO3 0.05–0.15 g and Ca-Cl22H2O 0.01 g. The pH was controlled at 7.2–7.6 by　adding NaHCO3 and NaOH solution. Temperature was controlled at 20–22ｏC. T

8、he influent flow rate was 150 L/day, the internal recirculation ratio and sludge recycled ratio was kept at 3.2 and 0.5, respectively. DO was controlled at 2–3 mg/L, sludge age was</p><p><b>　　Chart<

9、;/b></p><p>　　Table 1 The whole experiment period data</p><p>　　Analytical methods</p><p>　　According to standard methods [10], COD, MLSS, alkalinity, NH4+-N, NO2-N, NO3-N, TN, T

10、P and PO34 -P were measured. The DO and temperature were measured continuously using a WTW oxygen probe. Continuous monitoring of pH and ORP were carried out using WTW pH/Oxi340i on-line analyzer. Poly-bhydroxybutyrate (

11、PHB) was measured using a rapid gas chromatographic method described by Smolders et al. [11]</p><p>　　Results and discussion</p><p>　　Effect of influent C/N ratio on N and P removal </p>

12、<p>　　Figure 2a, b showed the TN and TP removal efficiencies at different C/N ratios, respectively, while influent C/P ratio was kept at about 40–45. It could be seen from Fig. 2a that increasing the C/N ratio from

13、3 to 7.1 resulted in the increase of TN removal efficiency steadily; the average TN removal efficiency reached 80.3% at C/N ratio of 7.1. </p><p>　　However, TN removal efficiency decreased gradually with the

14、 increase of C/N ratio from 7.1 to 12. As shown in Table 2, when mean influent C/N ratio was about 3.5, TN removal efficiency was 67.2%, effluent TN was 24.18 mg/L. In this case, organic loading was only 0.66 mgCOD/(m3 d

15、), nitrate concentration at the end of aerobic zone was 25.2 mg N/L, mainly because the sum of stored PHB plus external carbon source entering into the anoxic zone was lower correlative to nitrate concentration recycled

16、f</p><p>　　Table 2 In different regions of different C/N ratio of total nitrogen, total phosphorus, under the condition of COD, NO3-- N concentration</p><p>　　As shown in Table 3, it can be seen

17、 that COD/NOx was only 1.64 kgCOD/kgN; however, in order to realize complete denitrification, without PHB storage of biomass growth, the C/N ratio is the theoretical minimum of 2.86 kgCOD/kgN. But due to microorganism gr

18、owth, this ratio will normally be around 4 kgCOD/kgN [12]; as a result, it was impossible to achieve complete denitrification. When influent C/N ratio increased from 3.5 to 7.1, the corresponding TN removal efficiency in

19、creased 12.99%. Therefore</p><p>　　On the other hand, it could also be seen from Fig. 2b that increasing the C/N ratio from 3 to 5 resulted in the increase of TP removal efficiency gradually, the average TP

20、removal efficiency was larger than 90%, and mean effluent TP concentration was lower than 1 mg/L. It was demonstrated that low influent C/N has little effect on the TP removal efficiency because of the presence of DNPAOs

21、, while TP removal efficiency decreased with the increase of C/N ratio from 5 to12, and it almost decreased </p><p>　　Table 3 Anoxic zone under different influent C/N conditions than the C/NOx ratio and C/PO

22、4 ratio</p><p>　　Filipe et al. [14] stated that at higher organic loading, available COD would not be completely utilized by the PAOs in the anaerobic zone, the excess COD would favor the growth of glycogen-

23、accumulating organisms (GAOs), which led to the reduction of the PAO fraction in the activated sludge. It could be calculated according to Table 2 that COD consumed per unit P release increased gradually with the increas

24、e of organic loading, which was 4.94, 5.96, 7.29 and 18.24 mg COD/mg P for influent C/N ra</p><p>　　Effect of influent C/P ratio on N and P removal </p><p>　　Figure two</p><p>　　Fig

25、ure 5 presents the TN and TP removal efficiencies at different influent C/P ratios. Influent C/N ratio was maintained at 7–7.5. It could be seen from Fig. 5a that the C/P ratio hardly affected the TN removal, and TN remo

26、val efficiency was higher than 75% under different influent C/P ratios for the constant organic loading. </p><p>　　Table 4 In different regions of different C/P ratio of total nitrogen, total phosphorus, und

27、er the condition of COD, NO3-- N concentration</p><p>　　As shown in Table 4, average NO3-N and PO4 3-P removal efficiencies in the anoxic zone were between 70 and 85% and 60 and 71% for four mean C/P ratios

28、of 55, 45, 34and 23, respectively. According to Table 5, at almost the same influent organic loading, PHB concentration entering the anoxic zone decreased with the increase of influent C/P ratio, while COD concentration

29、increased with the increase of influent C/P ratio. Results showed that most of COD in the anaerobic zone was synthesized easily P</p><p>　　Table 5 Different water ratio of C/P under hypoxia in C/NOx ratio, t

30、he ratio of C/PO4segment</p><p>　　Yagci et al. [17] stated that at high C/P ratio, the existing organic carbon (mainly VFA) was more than the required carbon sources storing all available P because P was lim

31、iting, so that the net result was total P removal. However, when P was not limiting at low C/P ratio, the P storage capacity was limiting for the lack of soluble organic carbon, and there was always a net P level in the

32、effluent escaping EBPR. As a result, P removal efficiency decreased dramatically with the increase of C/P r</p><p>　　(18 kgCOD/kgN reported by Zeynep et al. [18]). The lack of soluble organic carbon limited

33、the P storage capacity; as a result, the TP removal efficiency decreased with the increase of C/P ratio from 42 to 66.5. On the other hand, Filipe et al. [14] observed that the presence of GAOs had important consequences

34、 on the phosphorus removal capability of BEPR systems: the competitive advantage of PAOs in BEPR systems was compromised because GAOs use the same substrate (VFAs) under the same conditions;</p><p>　　seen in

35、 Table 4 that the trends of COD removal efficiency was similar to that of different influent C/N ratios. Regardless of the influent C/P ratio, mean COD removal efficiency was always higher than 89%.</p><p>　

36、　Conclusions</p><p>　　A laboratory A2O reactor system with steady denitrifying phosphorus removal was operated for around 1 year to treat synthetic brewery wastewater, so as to test the effect of influent C/

37、N and C/P ratios on biological nutrient removal performance; meanwhile, the spatial profiles of DO, pH and ORP sensors in such system were investigated at different C/N and C/P ratios. The results showed that influent C/

38、N ratio had significant effect on the TN and TP removal efficiencies. The optimal TN and TP rem</p><p>　　在A2O工藝中污水組成對(duì)于脫氮除磷的影響以及控制</p><p><b>　　1、摘要</b></p><p>　　用一個(gè)有著穩(wěn)定脫氮

39、除磷性能的實(shí)驗(yàn)室厭氧—缺氧—好氧（即A2O）生物反應(yīng)器來進(jìn)行測(cè)試以確定進(jìn)水中C/N比（溶解性化學(xué)需氧量/總氮）和C/P比（溶解性化學(xué)需氧量/總磷）對(duì)模擬啤酒廢水的生物脫氮除磷的影響，同時(shí)，這些系統(tǒng)之中存在的空間型物體像溶解氧、PH、氧化還原電位傳感器等都將被研究。結(jié)果表明，C/N比對(duì)于總氮、總磷的去除效率以及從缺氧段到好氧段的磷的吸收有著顯著的影響。當(dāng)進(jìn)水中的C/N保持在7.1到5時(shí)，總氮和總磷的分別去除效率能夠達(dá)到最高。此外，當(dāng)總回流

40、比保持在3.5時(shí)，發(fā)現(xiàn)從缺氧段到好氧段的磷的吸收比例與進(jìn)水中的C/N比成線性相關(guān)的關(guān)系，這個(gè)系數(shù)為R2（R=0.685）。雖然進(jìn)水中的C/P比對(duì)于總氮的去除效率影響不大，不過它對(duì)于總磷的去除效率有重要的影響。此外，在進(jìn)水中的C/P比為42的時(shí)候，總磷的去除效率能夠達(dá)到最高。另一方面，通過觀測(cè)一些典型的因素像溶解氧、PH、氧化還原電位傳感器，能夠發(fā)現(xiàn)它們?cè)诓煌珻/N比、C/P比的進(jìn)水中有著相似的趨勢(shì)。有人建議使用簡(jiǎn)單的在線傳感器，這樣，構(gòu)

41、筑物的運(yùn)行狀態(tài)就很一目了然了。</p><p><b>　　2、關(guān)鍵詞</b></p><p>　　A2O工藝；C/N比值；C/N比值；溶解氧；PH；氧化還原電位。</p><p><b>　　3、試驗(yàn)程序</b></p><p>　　這個(gè)研究所用的模擬啤酒廢水包含（每公升）：啤酒為（乙醇含量3.5

42、%）2.8–3.4 mL；氯化銨為0.20–0.3 g；磷酸二氫鉀為0.02–0.08 g；七水硫酸鎂為0.05 g；碳酸氫鈉為0.05–0.15 g；二水氯化鈣為0.01 g。PH通過加碳酸氫鈉和氫氧化鈉的手段使之控制在7.2–7.6，溫度控制在20–22ｏC。當(dāng)進(jìn)水流量為150 L/d，內(nèi)循環(huán)比和污泥回流比分別控制在3.2 和 0.5，溶解氧控制在2–3 mg/L，污泥齡大約為12天時(shí)，厭氧、缺氧、好氧反應(yīng)器中的污泥齡相應(yīng)為3天，2

43、.4天和6.6天。</p><p>　　在整個(gè)實(shí)驗(yàn)中，混合液懸浮固體濃度（MLSS）都維持在3,000±500 mg/L。把進(jìn)水中的C/N比和C/P比分別控制在3到12和18到62之間，因?yàn)镃/N比和C/P比被認(rèn)為是在A2O工藝中影響脫氮除磷的兩個(gè)獨(dú)立變量。A2O反應(yīng)器多花了兩倍的細(xì)胞停留時(shí)間來獲得穩(wěn)定的C/N比和C/P比。這個(gè)反應(yīng)器中裝著的是從文昌污水處理廠（中國(guó)哈爾濱）運(yùn)來的活性污泥。這個(gè)系統(tǒng)花了兩

44、個(gè)月的時(shí)間來獲得了一些性質(zhì)穩(wěn)定的模擬啤酒廢水，這個(gè)實(shí)驗(yàn)進(jìn)行了大概一年，并且實(shí)驗(yàn)分成了兩部分，實(shí)驗(yàn)數(shù)據(jù)見圖一中的a、b與表一。</p><p>　　圖一：a圖與b圖 </p><p>　　圖a.總氮去除效率隨進(jìn)水C/N比的變化曲線 圖b.總磷去除效率隨進(jìn)水C/P比的變化曲線</p><p>　　表一：整個(gè)實(shí)驗(yàn)時(shí)期數(shù)據(jù)&l

45、t;/p><p><b>　　4、結(jié)果與討論</b></p><p>　　進(jìn)水中C/N比對(duì)N、P去除的影響</p><p>　　圖a、b分別表示了當(dāng)進(jìn)水中C/N比保持在40—45時(shí)，在不同C/N比的條件下TN和TP的去除效率，從圖a中可以看出，當(dāng)C/N比從3增加到7.1時(shí)，總氮的去除效率保持著穩(wěn)定的增長(zhǎng)；當(dāng)C/N比為7.1時(shí)，總氮的平均去除效率能夠

46、達(dá)到80.3%。然而，當(dāng)C/N比從7.1增加至12時(shí)，總氮的去除效率則逐漸的下降。</p><p>　　在下表二中可以看出，當(dāng)進(jìn)水的平均C/N比大約為3.5時(shí)，總氮的去除效率為67.2%，出水總氮濃度為24.18mg/L。在這種情況下，有機(jī)污染物負(fù)荷僅僅只有0.66 mgCOD/(m3/d)，硝酸鹽濃度在好氧段末段區(qū)域的濃度僅為25.2mg/L，造這種現(xiàn)象的主要原因就是水中原儲(chǔ)存的PHB加上外來的碳源進(jìn)入缺氧區(qū)，

47、這樣就降低了從好氧區(qū)末端循環(huán)過來的硝酸鹽的相關(guān)濃度。</p><p>　　表二：在不同區(qū)域不同C/N比條件下總氮、總磷、COD、NO3——N的濃度</p><p>　　在下表三中能夠看出，COD/NOx僅為1.64 kgCOD/kgN；然而，為了實(shí)現(xiàn)完全的脫氮，沒有生物量增長(zhǎng)造成的PHB儲(chǔ)存的影響，C/N比是理論上的最小值，這個(gè)值為2.86 kgCOD/kgN。但是由于微生物的生長(zhǎng)繁殖，C

48、/N比通常在4kgCOD/kgN左右，所以，不可能實(shí)現(xiàn)完全意義上的脫氮。當(dāng)進(jìn)水C/N比從3.5增加至7.1時(shí)，相應(yīng)的總氮去除效率增加了12.99%。因而，進(jìn)水中C/N比的提高能夠使總氮的去除效率提高， 因?yàn)橄鄳?yīng)的COD/NOx從5.42kgCOD/kgN增加至了9.89kgCOD/kgN。但是當(dāng)進(jìn)水中的C/N比從7.1增加到9.5時(shí)，總氮的去除效率有些輕微的減少，從去除率為80%處（出水濃度為7.5）減少至去除率為76.42%（出水濃度

49、為9,5），即使是在缺氧區(qū)相應(yīng)的COD/NOx比增加到了14.28kgCOD/kgN。結(jié)果表明，硝化作用的能力能夠在某種程度上被有機(jī)負(fù)荷達(dá)1.02mgCOD/（m3·d）的高濃度進(jìn)水所抑制。在表二中可知，出水硝酸鹽濃度與出水總氮濃度的比例從95.4%（濃度為7.5）減少至81.7%（濃度為9.5）。</p><p>　　另一方面，這樣的趨勢(shì)也能夠從圖b中看出來，當(dāng)C/N比從3增加到5時(shí)，這導(dǎo)致了總磷的去

50、除效率逐漸的增加，總磷的平均去除效率要大于90%，這就意味著出水總磷的濃度要小于1mg/L。這顯示了進(jìn)水中的C/N比即使很低，不過因?yàn)橛蟹聪趸哿拙拇嬖?，所以C/N比對(duì)總磷去除效率的影響也不是很大，然而，當(dāng)C/N比從5增加至12時(shí)，總磷的去除效率有些減少，并且在C/N比高于7.5的時(shí)候它幾乎是呈直線的減少。</p><p>　　表三：缺氧區(qū)在不同進(jìn)水C/N比條件下C/NOx 比和 C/PO4比</p>

51、;<p>　　有一些學(xué)者指出，在厭氧區(qū)，再高的有機(jī)負(fù)荷，可利用的CAD也不會(huì)被聚磷菌完全地利用，多余的COD則被聚糖菌的生長(zhǎng)繁殖所利用，這就導(dǎo)致了活性污泥中聚磷菌的減少。根據(jù)表二，能夠進(jìn)行如下計(jì)算：隨著有機(jī)負(fù)荷的增加，釋放每單位磷所要消耗的COD也在逐漸的增加，當(dāng)進(jìn)水中C/N比為3.5，5.1，7.1和9.5時(shí)，釋放每一單位磷所需要的COD值分別為4.94，5.96，7.29和18.24mgCOD/mgP。此外，進(jìn)水中C/

52、N比越高，由于碳源過多的緣故，硝化作用的效率就越低，同樣，因?yàn)镃OD/PO4值過高，導(dǎo)致了缺氧段磷去除的不充分，這個(gè)COD/PO4值能夠達(dá)到26.54 kg COD/kg P（理論上最小的C/P比為18 kg基質(zhì)COD/kg P），這就減少了磷的去除效率的進(jìn)一步增加。所以，總磷的去除效率隨著C/N比的增加而降低。</p><p>　　進(jìn)水中C/P比對(duì)N、P去除的影響</p><p><

53、;b>　　圖二：a圖與b圖</b></p><p>　　a：總氮去除效率隨進(jìn)水C/P比的變化曲線 b：總磷去除效率隨進(jìn)水C/P比的變化曲線</p><p>　　從圖二可以看出在進(jìn)水的C/P比不同時(shí)，總氮和總磷的去除效率的變化情況，進(jìn)水中C/N比保持在7—7.5。從圖二.a中能夠看出來C/P比很難影響到總氮的去除效率，在有機(jī)負(fù)荷恒定的情況下，且在進(jìn)水中的C/P比不同的

54、情況下，總氮的去除效率要高于75%。</p><p>　　表四：在不同區(qū)域不同C/P比條件下總氮、總磷、COD、NO3——N的濃度</p><p>　　在上表四中可以知道，在缺氧區(qū)，當(dāng)四個(gè)C/P比的平均值分別為55,45,34,和23時(shí)，NO3——N和的去除效率分別在70%—85%、60%—71%之間。根據(jù)表五，進(jìn)水有機(jī)負(fù)荷幾乎都一樣，進(jìn)入缺氧區(qū)的PHB的濃度隨著進(jìn)水中C/P比的增加而減少

55、。然而COD濃度則隨著進(jìn)水中C/P比的增加而增加。結(jié)果表明，厭氧池中的大部分的COD都被合成成了PHB，PHB提供了內(nèi)部碳源來完成C/P比很低的時(shí)候的脫氮作用，當(dāng)情況相反時(shí)，即C/P很高時(shí)，實(shí)驗(yàn)結(jié)果與Ma等人的報(bào)告結(jié)果相一致。另一方面，過量的COD進(jìn)入缺氧區(qū)，造成C/P比很高，這這就抑制了缺氧段磷的吸收，但缺氧區(qū)的COD/NOx比值總是大于需求值，正如表五所顯示的那樣（最小值為6.61kgCOD/kgN大于4kg基質(zhì)COD/kgN）；脫

56、氮?jiǎng)┍蛔鳛橥獠刻荚磥砜焖俚赝瓿擅摰饔?。因此，進(jìn)水中C/P比的變化很難影響到總氮的去除效率。然而，當(dāng)C/P比從21.9增加到42時(shí)，總磷的去除效率隨著C/P比的增加而增加，在C/P比接近42的時(shí)候，總磷的平均去除率要高于97%，然后從圖二.b中可以看出，總磷的去除率隨著C/P比值的增加（從42增加到66.5）而減少。</p><p>　　表五：不同的進(jìn)水C/P比值下缺氧段中C/NOx比值、C/PO4比值</

57、p><p>　　Yagci等人說明了在C/P比值比較高的情況下，現(xiàn)存的有機(jī)碳（主要為VFA）要多于所必需的碳源的數(shù)量，并且要供應(yīng)所有可以利用的磷，但是因?yàn)榱资怯邢薜?，這樣的結(jié)果那就是全部的磷都被去除了。然而，當(dāng)磷不再受低C/P比的限制時(shí)，磷的儲(chǔ)存容量還受到缺乏可溶性有機(jī)碳的限制，并且強(qiáng)化生物除磷不能去除所有的磷，所以出水中總是會(huì)有一定濃度的磷。結(jié)果就是，磷的去除效率竟然戲劇性地隨著C/P比的增加而減少?；诒砦?，實(shí)驗(yàn)

58、的結(jié)果同樣與Yagci等人的報(bào)告結(jié)果相符。能夠看出COD/PO4比隨著進(jìn)水中C/P比的增加而增加，當(dāng)進(jìn)水C/P比為45時(shí)，COD/PO4比為18.63 kgCOD/kgP，這個(gè)值要大于Zeynep等人說的必須的最小值：18 kgCOD/kgP。由于可溶性有機(jī)碳的缺乏限制了磷的儲(chǔ)存容量；結(jié)果就是，隨著C/P比從42增加到66.5時(shí)，總磷的去除效率反而減少。另一方面，菲利普等人觀測(cè)到，在強(qiáng)化生物除磷工藝系統(tǒng)中，聚糖菌的存在對(duì)于磷的去除能力有

59、著重要的影響；在強(qiáng)化生物除磷工藝中，聚磷菌以前的競(jìng)爭(zhēng)性優(yōu)勢(shì)已經(jīng)沒有了，因?yàn)榫厶蔷谕粭l件下使用的是同一種基質(zhì)（有機(jī)酸）；但是強(qiáng)化生物除磷系統(tǒng)中，如果有大量</p><p><b>　　5、結(jié)論</b></p><p>　　用一個(gè)有著穩(wěn)定脫氮除磷效果的實(shí)驗(yàn)室A2O反應(yīng)器系統(tǒng)來進(jìn)行處理模擬啤酒廢水的實(shí)驗(yàn)，這個(gè)實(shí)驗(yàn)進(jìn)行了將近一年的時(shí)間，主要用來測(cè)試不同進(jìn)水中的C/N、C/

60、P比值對(duì)生物養(yǎng)分去除的效果；同時(shí)，在進(jìn)水中C/N、C/P比值不同的情況下，對(duì)這些系統(tǒng)中間的溶解氧、PH以及氧化還原電位感應(yīng)器進(jìn)行測(cè)試。結(jié)果顯示，進(jìn)水中的C/N比對(duì)于總氮和總磷的去除效率有重要的影響。當(dāng)C/N比值在范圍5—7.1之間時(shí)，能夠達(dá)到總氮和總磷的最佳去除效率。此外，在總回流比恒定的情況下，發(fā)現(xiàn)從缺氧區(qū)到好氧區(qū)的磷的吸收與進(jìn)水中的C/N比呈線性關(guān)系。進(jìn)水中的C/N比對(duì)于總磷的去除效率有重大的影響，然而對(duì)于總磷的去除效率卻幾乎沒有影