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40個廢水調試指導方案介紹(一)

2022-05-12  來自: 環保水圈 瀏覽次數:614

一、用A-O法處理含有氨氮污水,以前運行正常,經常在回流沉淀池出現污泥厭氧反硝化,引起污泥上浮現象,污泥流失,影響出水水質。如何解決?


廢水調試


答:解決辦法

1、控制好反硝化條件,盡可能去除硝酸氮;

2、增加沉淀池的出泥量,以降低沉淀池的污泥層高度,使污泥在泥層的停留時間減少,可防止污泥缺氧;

3、條件允許的話(不影響缺氧區的缺氧環境)盡可能增加好氧區的溶解氧,使進入沉淀池的污泥不缺氧。上述1是為了使進入沉淀池的硝酸氮大大減少,不會發生嚴重的反硝化,后二條措施是即使有大量硝酸氮進沉淀池,但由于不缺氧也就不易發生反硝化。

二、目前我廠處理規模為4萬噸/日,有兩個濃縮池,設計污泥量為5600kgDS/d,污泥負荷為50kgDS/㎡•d。但因施工造成兩個池的進泥和出泥不平衡且不容易調整。經常造成一池污泥過多發生厭氧并導致濃縮機負荷過高燒壞電機。

前段時間,在一個濃縮池故障不能及時排除的情況下,采用單池運行,污泥量在4000kgDS/d左右,污泥負荷為61kgDS/㎡•d。在此負荷下運行,該池沒有出現因負荷過高而導致濃縮機故障。單池運行比雙池運行管理簡單且出泥穩定。試問,濃縮池的負荷上限可達多少。科學范圍又是多少?

答:是管理不當造成的,二池的進泥量可以通過進泥閥調節的,如果象你所說的因施工問題二池進泥量不能調節,那濃縮池的出泥量總可以調節吧,進泥量大,又不能關小,就要增加出泥量,把出泥調節閘門開大,使池內污泥層下降,這樣可減少濃縮污泥在池內的停留時間,以防污泥發酵。濃縮池還可以交替運行,運行管理中的調節手段是多方面的。至于濃縮池的負荷等與污泥含水率、性質等有關,各廠的情況都不同的。

三、MLSS可用懸浮物的方法測定嗎?

答:MLSS只是很粗略地表示污泥中微生物量的多少,當然不能用懸浮物的方法測定,因為MLSS包括固定固體和揮發固體二類,固定固體是無機物,揮發固體是有機物+微生物,如果用懸浮物的方法測定。一些溶解性的有機物和游離細菌就流失了。

四、在運行過程中,氧化溝表面有一層厚厚的污泥堆積,粒徑約1mm左右的污泥顆粒泛黃,時常會造成二沉池大量飄泥,污泥返白,有絮體隨出水一同流出,SV30迅速下降,處理效果喪失,堆積污泥減薄消除。周而復始,請問其成因和控制措施。

答:說明污泥已失去活性,使ESS增加。有二種可能:一是污泥自身氧化;二是污泥中毒。從你所描述的現象看,前者的可能性大,可測定一下比耗氧速率,即內源耗氧速率與基質耗氧速率之比來確定,針對性采取措施。

五、ABA段如何控制?是從一沉池以等同的流量給A段連續回流嗎?SV30應控制在多少?

答:A段的回流比應該大一些,但也不能使污泥在一沉池的停留時間太短,雖然A段主要是吸附為主,但也有一定的生物降解作用的,生物降解大多在沉淀池內進行,只有將吸附在污泥表面的有機物降解,才能恢復吸附能力。應該用MLSS來控制,在污泥沉降性能穩定時也可用SV30,要根據實際情況定

六、如果一家污水廠運行一兩年處理效果沒達到較佳狀態,那是不是應該考慮重新培菌(換泥)?換泥跟開始時的培菌有什么不一樣呢?

答:不用換!如果運行條件不變,換了也會一樣的,即使你用優勢菌種投加也沒用,只能維持一段時間,重要的是控制好運行條件,如果是設計上的的問題要及時整改。

七、調試工業廢水

工藝為水解+厭氧+好氧池1+好氧池2+沉淀。由于安裝問題,曝氣池布氣不均勻(圓形曝氣頭曝氣),每個曝氣器處,均有一個類似噴泉上下翻滾(直徑1m左右),曝氣不均,對處理效果有多大影響?還發現曝氣區填料掛膜較少,鏡檢有大的后生動物,沒有發現其它生物,填料生物膜表面為淡黃,曝氣區外的生物膜厚達3cm,能給我解示一下嗎?

答:你所說的情況不能說是曝氣不均,是正常現象。還有你說生物膜不多,不知是多少?如生物膜把填料基本覆蓋就很好了,至于說曝氣區外的生物膜厚達3cm就是嚴重結球了,要采取措施,如用大氣量沖刷和厭氧脫膜等措施。

八、有關接觸氧化池的下例問題。

1接觸氧化池在放空時,填料上污泥能存活多少時間?

2當接觸氧化池處理能力下降時,要不要投加營養?

3對于泡沫,加煤油消泡你認為有效嗎,若有效通常要加多少?

回答如下:

1接觸氧化池放空后并不是生物膜污泥能存活多長的問題,而是要避免軟性填料曬干而板結,板結后再浸放水中就很難再伸展開,要防止這樣的情況出現;

2接觸氧化池處理能力的下降應從多因素考慮,其中生物膜的厚度控制很重要,膜太厚會嚴重影響處理能力,還要注意池放空時只能緩緩放,否則掛有大量生物膜的軟性填料架會倒塌或變形;

3化學性泡沫用水噴淋較有效(不能直接用水沖),我不贊同用煤油之類的方法消泡。

九、某廠近一周的進水、出水及生化池各數據平均如下:

進水:BOD253COD810PH7.9SS286;色度:32倍;氨氮:28;總氮:64;總磷:6.0

出水:BOD4.8COD74PH8.1SS12;色度:8倍;氨氮:7.6;總氮:22.8;總磷:1.02

生化池:MLSS4200MLVSS2340SV47.2;污泥指數:118.9;泥齡是35天。

采用的是改良型活性污泥處理工藝,目前的進水大約只有2.5萬噸/天(設計是5萬噸),大部分是工業廢水,另有少量高濃度的垃圾滲濾液工藝流程是曝氣沉砂池-后生化池-后二沉池,沒有設置接觸池與水解池。生化池是鼓風機供氣,深水轉碟曝氣,連續進水時溶解氧達不到1mg/L,停止進水后溶解氧緩慢上升至4-5mg/L左右。進水的嚴重超標及構筑物的缺陷,導致了生化池的負荷很高,且污泥濃縮池很小(180立方),有相當部分剩余污泥重回到進水泵房去。

遇到問題如下:

1二沉池在進水后經常發現有活性污泥懸浮顆粒,是靜沉時間不足還是難以沉淀?

2三個二沉池均發現聚集的紅蟲(水蚤),水蚤好像是處理水質好的表現,是不是因為污泥濃度高導致大量繁殖?

3二沉池有時發現有薄薄的一層飄泥,是不是污泥的沉降性能很差,生化池曝氣不足?還是污泥回流不及時?

4二沉池三角堰板上容易青苔或是藻類滋生,有什么方法克服?

5認為污泥老化嚴重,要將MLSS控低為3000-3500之間或更低些,增加剩余污泥排放量,降低泥齡,這樣生化池的耐沖擊會不會下降?出水水質會不會上揚?

答:污泥是有些老化,但不算很嚴重,泥齡已達35天,按此推算,污泥負荷不到0.03。控制目前污泥濃度的2/3就足夠了,應該逐漸減少污泥濃度,水蚤對出水沒影響,分析取樣時不要取到水蚤。還要注意沉淀池泥層控制,二沉池三角堰板上青苔和藻類只能人工清除。

十、石油化工廢水兩級生化處理,一 級是圓形完全混合式曝氣池,二級是推流曝氣池,一 級DO0.2mg/L,二級DO5.0mg/L。這段時間一 級生化進水PH8.0,出水6.5,二級生化后PH5.78,超出指標6-9的范圍,什么原因?

答:一 級DO低很正常,因為污泥負荷高,一 級pH下降的原因可能是負荷太高發生酸化,二級出水pH下降可能是硝化反應消耗堿度造成的。

衡水市衡美水處理設備有限公司,專營 淺層砂過濾器 過濾器 全自動加藥裝置 原水處理設備 等業務,有意向的客戶請咨詢我們,聯系電話:0318-2987119

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