延曝气 嗯延肘曝气的特点 曝气肘间很长,达24h甚至更长,MLSS较高,达 到3000~6000mg/L; 活性污泥在肘间和空间上部分处于内源呼吸状 态,剩余污泥少而稳定,无需消化,可直接排放 适用于污水量很小的场合,近年来,国内小型污 水处理处理糸统多有使用。 0 Conventional extended geration secondary carmer Imuvert Aeration tank ScreenIngs Reum acided sude The exdended aeration process is similar o the conventional plug-Aow process except that it operates in the endogenous respiration phase of the growth aurve, which es a low organic baoding and long aeration time. Because of the long SRTs(20 to 30 d and t s on the order of 24 h demand equipment design is controlled by mixing needs and not oxygen he process is used eXtensively for preengineered plants for mol communities. Generally, primary daril USeC canters ore des lower hydraulic loading rates than conventione fers如 o befter handle lar vrate variations typical of smoll communities. Although the biosolids ore well stabilized ional biosolids stabilization is required to permit beneficial reuse
11 延时曝气的特点： 曝气时间很长，达24h甚至更长，MLSS较高，达 到3000～6000mg/L； 活性污泥在时间和空间上部分处于内源呼吸状 态，剩余污泥少而稳定，无需消化，可直接排放； 适用于污水量很小的场合，近年来，国内小型污 水处理处理系统多有使用。 延时曝气
接触稳定法 图14-29 混合液曝气过程中第一阶段BOD5的下降是由于吸附 作用造成的,对于溶解的有机物,吸附作用不大或没 有,因此,把这种方法称为接触稳定法,也叫吸附再生 法,混合漩的曝气完成了吸附作用,回流污泥的曝气 成稳定作用 接触稳定法 这一方法直接用于原污水的处理比用于初沉池的出流效果 好,初沉池可以不用;剩余污泥量增加。 吸附池 沉淀池 污泥回流 再生池 剩余污泥 图14-30接触稳定法流程
12 接触稳定法 混合液曝气过程中第一阶段BOD5的下降是由于吸附 作用造成的，对于溶解的有机物，吸附作用不大或没 有，因此，把这种方法称为接触稳定法，也叫吸附再生 法，混合液的曝气完成了吸附作用，回流污泥的曝气完 成稳定作用。 这一方法直接用于原污水的处理比用于初沉池的出流效果 好，初沉池可以不用；剩余污泥量增加。 接触稳定法
Primary Stablize Cotta eturn activated suage Contact stabilization uses two separate tanks or compartments for the treat nent of the wastewaer and stabilization of the activated sludge. the stabi ized activaed sluge is mixed with the invent ( either raw or setted)waste- The contact zone detention time is relatively short 0 t 60 min), and the MLsS concentration in the contact zone is lower thon that in the stabilization zone. ra d of soluble bod occrs in he concoct zone, and colloidal and particulate organics are captured in the activated-shudge fox for degradation laker in the stabilization zone. In the ed sludge(RAS)is aerated and the fion time is in the order of i to 2 h t mainain a sufficient SRT for sludge stabilization. Because the mlss concentration is so much higher in the stabi aton zone, the oonlod-stobilizotion process requires much less aeration processes for the same RT. The process was developed for BOD removal, and the short monad time limits the amount of soluble bod degraded and N, N oxidation 氧化沟 氣化沟是延肘曝气法的一种特殊形式,宅的池体狭长,池 深较浅,在沟槽中设有表面曝气裝置。 曝气裝置的转动,推动沟内液体迅速流动,取得曝气和搅 拌两个作用,沟中混合液流速约为0.3~0.6m/5,使活性污 泥呈悬浮状态。 同流行 当1-3氯化四系 图14-2卡罗式氧化内
13 氧化沟是延时曝气法的一种特殊形式，它的池体狭长，池 深较浅，在沟槽中设有表面曝气装置。 曝气装置的转动，推动沟内液体迅速流动，取得曝气和搅 拌两个作用，沟中混合液流速约为0.3～0.6m/s，使活性污 泥呈悬浮状态。 氧化沟
ni)Oxidation ditch nidation dich consists of a ring or oval-shaped channel equipped reened wastewater enters the channel and is combined with the return activated sludge. The tank promote unidirectional annel ow, so that the energy used for aeration is sufficient to provide ixing in a system with a relatively long hydroulic retention fime. The sludge in suspension. At these channel velocites, the mixed liq completes a tank circulation in 5-15 min, ond the magnitude of th hannel Row is such that it can dilute he in fluent wastewater How by o the channels. As the denitrification may oocur. Brush bype or surface type mechani Sec. 5-12 in Chap 5). Secondary edimentation tonks are used for most applications, and in some cases intrachannel darifiers have been used (k)Or )rba mM Secondary Efent Recycle optional) Retum activated sude The ObalrM process is a variation of the oxidation ditch and uses a series of concentric channels within the same structure Wastewater enters the arger outer channel and mixed liquor Roy the shructure through at least two more ore entering an intermal darifier or a distribution box. Disk aerators mounted on a horizonal shaft provide aeration. Channel depths range up to 4.3 m (14 f). One version of the Orbal design( Bionutre TM) limits the geration rate in the hrst channel so that both nitrification tritiation anoxiC andiron)occur
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纯氧曝气 纯氧代替空 气,可以提高生物处 理的速度。纯氧曝气 池的构造见图14 回流污泥 34。 图14-34纯氧气池构造简图 在密闭的容器中,谑解氧的饱和度可提高,氧嵱解的 推动力也随着提高,氣传递速率增加了,因而处理效果 好,污泥的沉淀性也好。纯氣曝气并没有改寶活性污泥或 微生物的性质,但使微生物充分发挥了作用。 「纯氣曝气的缺点是纯氣发生系京易出现故障,裝置复 杂,运转管理较麻烦。 Retm activated sludae 上中可如 homb7 powe gas and m小y ↓ range from 40 to 60 per the first soge to 20 percent in the last ge. A high ales are possible so that pure oxygen systems can have a higher MLSS ncentration and operate at a shorter and higher volumetric organic loadings than conventional about 2 bo3 times ter than that by conventional aeration systems n convention activaed -sludge processes. Nitrification ability is limited duoed space requirement and greatly reduced quantities of off gas if 15
15 纯氧代替空 气，可以提高生物处 理的速度。纯氧曝气 池的构造见图14－ 34。 纯氧曝气 纯氧曝气的缺点是纯氧发生器容易出现故障，装置复 杂，运转管理较麻烦。 在密闭的容器中，溶解氧的饱和度可提高，氧溶解的 推动力也随着提高，氧传递速率增加了，因而处理效果 好，污泥的沉淀性也好。纯氧曝气并没有改变活性污泥或 微生物的性质，但使微生物充分发挥了作用