【摘要】：隨著我國城市化進(jìn)程及人口的劇增,廢水排放量快速增長,導(dǎo)致許多城市河流受到不同程度的污染,其中有機(jī)污染比較普遍,表現(xiàn)為水體嚴(yán)重缺氧,甚至發(fā)黑發(fā)臭。河道黑臭現(xiàn)象在我國目前已普遍存在。曝氣充氧技術(shù)因其投入低成本、見效快,在國內(nèi)外污染河道治理中被廣泛使用。曝氣充氧有利于氧傳質(zhì),提高水體溶解氧水平,恢復(fù)和增強(qiáng)水體中好氧微生物活性,抑制底泥氮、磷的釋放,增加液體混合和污泥絮凝,從而使水體中污染物得以去除,改善河道水質(zhì)情況。本文通過模擬試驗(yàn)方法,分析曝氣設(shè)備及強(qiáng)度、曝氣方式、曝氣位置等對河道污染治理的作用及機(jī)理,以期為河道水體修復(fù)提供技術(shù)支持。本文的主要研究結(jié)論如下:1)微米曝氣裝置可以快速提高水體中溶解氧含量,CODcr,NH4+-N,TN和土臭素Geosmin的最大去除率分別是51.39%、44.10%、38.96%、44.80%,去除效果高于普通曝氣。間歇曝氣下CODcr和NH4+-N的去除率分別是51.44%和72.93%,分別比連續(xù)曝氣低3.83%和1.93%。但間歇曝氣對水體TN去除率明顯高于連續(xù)曝氣。間歇曝氣有利于脫氮,TN去除率提高,也可以減少工程運(yùn)行費(fèi)用。2)人工曝氣促使試驗(yàn)前期底泥污染物快速釋放,使上覆水體中各項(xiàng)污染物指標(biāo)上升;隨著水體DO濃度的增加,硝化細(xì)菌、嗜磷菌等好氧細(xì)菌活性增強(qiáng),水體中CODcr、氨氮、TN和TP得到降解或轉(zhuǎn)化,濃度快速下降。試驗(yàn)期內(nèi),人工曝氣底泥中TN、TP的平均釋放速率分別為:-0.11g/(m2·d)和-0.02g/(m2·d)。水體中DO濃度增加,可以有效抑制底泥中氮和磷的釋放,對水體有機(jī)污染物、TN及TP有一定削減作用。3)曝氣充氧可以改變底泥的理化性質(zhì),間接影響間隙水、底泥中各形態(tài)氮的含量。在同樣曝氣量下,底泥曝氣比水體曝氣能夠更好的去除底泥中污染物,并減少再次釋放,在一定深度內(nèi),曝氣深度越深,處理效果越好,X-15組CODcr、NH4+-N、TN及TP的除率分別為69.73%、78.36%、45.98%及84.21%。因此,充分利用底泥曝氣技術(shù)及合理選擇曝氣位置有助于河道水體環(huán)境修復(fù)。
[Abstract]:With the rapid increase of urbanization and population in China, the discharge of wastewater increases rapidly, which results in many urban rivers being polluted to varying degrees, among which organic pollution is common, which is characterized by serious lack of oxygen in the water body and even blackness and odour. At present, the phenomenon of blackness and odour in river channels is widespread in our country. Aeration oxygenation technology is widely used in the treatment of polluted rivers at home and abroad because of its low cost and quick effect. Aeration and oxygenation is beneficial to oxygen transfer, improve the level of dissolved oxygen in water, restore and enhance aerobic microbial activity, inhibit the release of nitrogen and phosphorus from sediment, increase liquid mixing and sludge flocculation, so as to remove pollutants in water. Improve the water quality of the river. In this paper, the effect and mechanism of aeration equipment and intensity, aeration mode and aeration position on river pollution control are analyzed by means of simulation test method, in order to provide technical support for river water body restoration. The main conclusions of this paper are as follows: 1) the content of dissolved oxygen in water can be increased rapidly by micron aeration device. The maximum removal rates of CODcr,NH4 NTN and soil odor Geosmin are 51.39% 44.10% and 38.96% 44.80%, respectively. The removal efficiency is higher than that of ordinary aeration. The removal rates of CODcr and NH4-N under intermittent aeration were 51.44% and 72.93% respectively, which were lower than those of continuous aeration by 3.83% and 1.93%, respectively. However, the removal rate of TN by intermittent aeration was significantly higher than that by continuous aeration. Intermittent aeration is beneficial to denitrification, TN removal rate is increased, and project running cost can be reduced. 2) artificial aeration can promote the rapid release of pollutants from sediment in the early stage of the test, and increase the pollutant indexes in the overlying water. With the increase of the concentration of DO in water, the activity of aerobic bacteria such as nitrifying bacteria and phosphophilic bacteria increased, CODcr, ammonia nitrogen, TN and TP were degraded or transformed, and the concentration decreased rapidly. During the test period, the average release rates of TN,TP in artificially aerated sediment were-0.11g/ (m2 d) and-0.02g/ (m 2 d).), respectively. The increase of DO concentration in water can effectively inhibit the release of nitrogen and phosphorus in sediment, and reduce organic pollutants in water, TN and TP. 3) aeration and oxygenation can change the physical and chemical properties of sediment and indirectly affect the interstitial water. The content of nitrogen in sediment. Under the same aeration rate, sediment aeration can better remove pollutants and reduce re-release than water aeration. In a certain depth, the deeper the aeration depth, the better the treatment effect, X-15 group CODcr,NH4-N, The removal rates of TN and TP were 45.98% and 84.21%, respectively. Therefore, making full use of sediment aeration technology and reasonable selection of aeration location are helpful to the restoration of river water environment.
【學(xué)位授予單位】：河北科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：X52

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 方宇翹;裘祖楠;馬梅芳;姚振淮;漆德瑤;;污染河流底泥釋放有機(jī)物的模擬研究[J];環(huán)境污染與防治;1989年02期

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本文編號：2407878