版塊導(dǎo)航: 正在加載中...

應(yīng)《網(wǎng)絡(luò)安全法》要求，自2017年10月1日起，未進(jìn)行實(shí)名認(rèn)證將不得使用互聯(lián)網(wǎng)跟帖服務(wù)。為保障您的帳號(hào)能夠正常使用，請(qǐng)盡快對(duì)帳號(hào)進(jìn)行手機(jī)號(hào)驗(yàn)證，感謝您的理解與支持！

24小時(shí)熱門版塊排行榜

北京石油化工學(xué)院2026年研究生招生接收調(diào)劑公告

返回列表

本帖產(chǎn)生 1 個(gè) 翻譯EPI ，點(diǎn)擊這里進(jìn)行查看

炮打總統(tǒng)府

金蟲 (小有名氣)

應(yīng)助: 5 (幼兒園)
金幣: 837.3
散金: 6
帖子: 112
在線: 55.1小時(shí)
蟲號(hào): 1381611
注冊(cè): 2011-08-27
性別: GG
專業(yè): 高分子合成化學(xué)

[求助] 求高手翻譯，環(huán)境工程水處理方面！

Processes for biological nutrient removal (BNR) typically adopt alternating anaerobic, anoxic, and aerobic zones in order to remove nitrogen and phosphorous, as well as organic compounds, from the wastewater. In these BNR processes,nitrification reaction relies on slow-growing, autotrophic bacteria that require a long solids retention time (SRT) and a relatively high oxygen concentration, while the denitrification reaction requires an organic electron donor that is not always sufficient in the influent wastewaters .
  Noting the benefits of shortcut biological nutrient removal (SBNR) process, many researchers have tried to obtain consistent nitrite accumulation in nitrification, which is a key prerequisite for successful SBNR . From a biological viewpoint, two distinct approaches are possible. First, the SHARON (single reactor system for high activity ammonia removal over nitrite) process employs a short (1–2days) SRT and a high reaction temperature (35 8C) in order to selectively wash out nitrite oxidizers . SHARON process is the most suitable for wastewaters already at high temperature
and with little organic carbon. The second approach uses a high pH and, consequently, a high unionized ammonium concentra-tion  or a low DO  to slow nitrite oxidation preferentially and washout nitrite-oxidizing bacteria. The second approach is the most suitable for insufficiently buffered wastewaters at lower temperatures (<20 8C). A key operating factor for any SBNR process using either approach to eliminate nitrite oxidation is to avoid retarding ammonium oxidation toomuch.
  The focus of this work was on the second approach. A number of researchers  have shown that a high concentration of unionized ammonia, or free ammonia (FA),inhibits nitrite oxidizers. Anthonisen et al. reported that inhibition of nitrite oxidation by FA began at 0.1–1.0 mg FA/L, while that of ammonium oxidation at 10–150 mg/L. Thus, a selective inhibition of nitrite oxidation should be achieved within a FA concentration of 1.0–10 mg/L.
  One challenge of the second approach is that the threshold concentration of FA seems to increase gradually with time .Villaverde et al. concluded that the nitrifica-tion–denitrification process via nitrite is not likely to be stable or feasible for long periods of time due to the acclimation of nitrite oxidizers to FA. Nitrite oxidizers may also be more sensitive to low DO (0.5 mg/L) than ammonium oxidizers, depending on SRT . Another potential pathway in shortcut denitrification is to have rapid denitrifica-tion of nitrite as soon as it is produced by the ammonium oxidizers. Simultaneous denitrification with nitrification is now well established n aerobic reactors in which the DO level is poised at a suitably low level, typically 0.5–1 mg/L. Rapid scavenging of nitrite for denitrificationaugments the benefits of FA or low DO for inhibiting nitrite oxidizers.
  A hybrid shortcut biological nutrient removal (HSBNR) process integrates biofilm within a suspended-growth system to maximize the hold-up and SRT of ammonium oxidizers, while operating with relatively high FA and low DO concentrations to inhibit nitrite oxidation and enhance rapid denitrification of nitrite . The HSBNR offers the potential of three selective pressures against nitrite oxidation: high FA, low DO, and rapid direct denitrification. The HSBNR also should have the advantage of a short hydraulic retention time (HRT) and small system volume, due to the accumulation of biofilm biomass along with suspended biomass. The hybrid system was tested in a batch mode to demonstrate its promise for stabilizing
SBNR .
  This study evaluates the hybrid reactor in the continuous-flow mode, which tests the long-term performance of shortcut nitrogen removal and investigates the relative importance of factors affecting nitrite accumulation in the HSBNR reactor:
concentrations of FA, DO, and direct denitrification.

回復(fù)此樓

» 猜你喜歡

290求調(diào)劑已經(jīng)有3人回復(fù)
求調(diào)劑已經(jīng)有3人回復(fù)
327求調(diào)劑已經(jīng)有3人回復(fù)
085600 286分材料求調(diào)劑已經(jīng)有11人回復(fù)
一志愿河北工業(yè)大學(xué)0817化工278分求調(diào)劑已經(jīng)有15人回復(fù)
085601材料工程找調(diào)劑已經(jīng)有15人回復(fù)
材料與化工272求調(diào)劑已經(jīng)有15人回復(fù)
南京大學(xué)化學(xué)調(diào)劑已經(jīng)有14人回復(fù)
一志愿北京工業(yè)大學(xué)，324分求調(diào)劑已經(jīng)有6人回復(fù)
求調(diào)劑已經(jīng)有5人回復(fù)

環(huán)游世界！

1樓 2012-02-01 15:04:31

已閱回復(fù)此樓關(guān)注TA 給TA發(fā)消息送TA紅花 TA的回帖

qliangem

銅蟲 (小有名氣)

翻譯EPI: 6
應(yīng)助: 0 (幼兒園)
金幣: 63.6
紅花: 1
帖子: 66
在線: 71.9小時(shí)
蟲號(hào): 1566342
注冊(cè): 2012-01-06
專業(yè): 水文、水資源

【答案】應(yīng)助回帖

★ ★ ★ ★
愛與雨下(金幣+4): 2012-02-04 22:36:36
炮打總統(tǒng)府(金幣+10, 翻譯EPI+1): ★★★很有幫助感謝交流！ 2012-02-05 13:55:26

翻譯如下，僅供參考。不當(dāng)之處請(qǐng)指正。

污水的生物脫氮除磷工藝通常采用厭氧、缺氧和好氧處理的交替進(jìn)行來實(shí)現(xiàn)脫氮除磷和減少有機(jī)物質(zhì)。在這些生物脫氮除磷工藝中，硝化反應(yīng)依賴于生長(zhǎng)緩慢的自養(yǎng)型細(xì)菌，而自養(yǎng)型細(xì)菌的培養(yǎng)需要較長(zhǎng)的污泥停留時(shí)間和較高濃度的溶解氧。另一方面，反硝化反應(yīng)需要有機(jī)物提供電子，而有些污水中并不含有足夠濃度的有機(jī)物。
短程生物脫氮除磷工藝（SBNR）具有多種優(yōu)勢(shì)。而該工藝的能夠?qū)崿F(xiàn)的重要先決條件是硝化反應(yīng)過程中的亞硝酸含量需要維持穩(wěn)定。從生物法的角度講，有兩種可能的解決方案。一種方法是SHARON (single reactor system for high activity ammonia removal over nitrite)工藝。該工藝采用短污泥停留時(shí)間（1 – 2天）和高反應(yīng)溫度（35.8 C）來選擇性地消滅亞硝酸鹽氧化細(xì)菌。SHARON工藝對(duì)高溫和機(jī)物含量低的廢水特別適用。第二種方法采用提高pH值增加非離子氨濃度或者降低溶解氧的方法來減緩亞硝酸氧化過程并消滅亞硝酸鹽氧化細(xì)菌。此方法適用于處理緩沖不足的低溫廢水（<20.8C）。對(duì)于任一種短程生物脫碳除磷工藝而言，在操作中防止亞硝酸鹽氧化的關(guān)鍵點(diǎn)在于避免使氨氧化過于緩慢。
本次研究的著重點(diǎn)在于第二種方法。已有研究成果顯示在高濃度非離子氨（或稱游離氨，或FA）存在的情況下，亞硝酸鹽氧化會(huì)受到抑制。Anthonisen研究組的報(bào)告中指出游離氨濃度在達(dá)到0.1–1.0 mg /L以上時(shí)即能對(duì)亞硝酸鹽氧化產(chǎn)生抑制作用，而在達(dá)到10-150mg/L以上時(shí)才會(huì)對(duì)氨氧化反應(yīng)產(chǎn)生抑制作用。因此，選擇性地抑制亞硝酸氧化是可以通過將游離氨的濃度范圍控制在1.0–10 mg/L而實(shí)現(xiàn)的。
第二種方法存在的一個(gè)技術(shù)問題是游離氨濃度的閾值隨時(shí)間推移會(huì)逐漸增加。Villaverde的研究成果指出，在亞硝酸鹽氧化細(xì)菌對(duì)游離氨的適應(yīng)過程中，通過亞硝酸鹽的硝化-反硝化反應(yīng)是不會(huì)長(zhǎng)期穩(wěn)定的。此外，在不同的污泥停留時(shí)間條件下，亞硝酸鹽氧化細(xì)菌可能比氨氧化細(xì)菌更容易受低溶解氧濃度的影響。另一種短程反硝化反應(yīng)的途徑是在氨氧化細(xì)菌產(chǎn)生亞硝酸鹽后使其即時(shí)反硝化。目前已經(jīng)存在完善的技術(shù)可以在適當(dāng)?shù)蜐舛菵O（0.5-1mg/L）的厭氧反應(yīng)器中令反硝化與硝化反應(yīng)同時(shí)進(jìn)行。快速消耗可用于反硝化反應(yīng)的亞硝酸鹽能增加游離氨或低溶解氧抑制亞硝酸氧化細(xì)菌的效果。
聯(lián)合性的短程生物脫氮除磷工藝（HSBNR）在懸浮污泥系統(tǒng)中結(jié)合了生物膜，該設(shè)置可最大化氨氧化細(xì)菌的含率和污泥停留時(shí)間，并同時(shí)采用較高的游離氨和較低的溶解氧濃度用于抑制亞硝酸鹽的氧化和提高亞硝酸鹽的反硝化。HSBNR可能提供三種機(jī)制用于抑制亞硝酸氧化：高游離氨、低溶解氧、快速的直接反硝化。另外，因?yàn)樯锬ど仙镔|(zhì)與懸浮生物質(zhì)可以一同積累，所以HSBNR的優(yōu)勢(shì)還包括擁有較短的水力停留時(shí)間和較小的系統(tǒng)容積。聯(lián)合系統(tǒng)在間歇模式下測(cè)試的結(jié)果顯示了在穩(wěn)定SBNR方面的良好前景。
此次研究評(píng)估了聯(lián)合反應(yīng)器在連續(xù)流條件下的處理效果。測(cè)試了其影響短程脫氮的長(zhǎng)期效果并研究了在聯(lián)合短程脫氮除磷工藝中影響亞硝酸鹽累計(jì)的三種因素的相對(duì)重要性，即FA濃度、溶解氧和直接反硝化。

贊一下(4人)

回復(fù)此樓

2樓2012-02-04 13:41:41

已閱回復(fù)此樓關(guān)注TA 給TA發(fā)消息送TA紅花 TA的回帖

相關(guān)版塊跳轉(zhuǎn) 我要訂閱樓主炮打總統(tǒng)府的主題更新