【摘要】：近年來,納米材料(NMs)因其特殊優(yōu)異的物理化學(xué)性質(zhì)而被廣泛應(yīng)用在人類生產(chǎn)生活中的方方面面。大量生產(chǎn)和使用NMs將難以避免地導(dǎo)致其在水環(huán)境中的釋放。目前,NMs對人體和其它生物的潛在風(fēng)險(xiǎn)得到學(xué)者廣泛關(guān)注,但是關(guān)于它對污水生物處理工藝可能帶來的風(fēng)險(xiǎn)研究還較為缺乏。本文選取當(dāng)前極具市場前景之一的氧化鈰納米顆粒(CeO2 NPs),研究它對活性污泥系統(tǒng)(ASS)急性和慢性作用后,出水水質(zhì)和ASS中微生物群落結(jié)構(gòu)的變化,得到結(jié)論如下：1.CeO2 NPs對ASS中好氧微生物3h接觸毒性試驗(yàn)表明當(dāng)Ce02NPs濃度小于100 mg.L-1時(shí),其對微生物毒性效應(yīng)較弱,當(dāng)濃度大于100 mg-L-’時(shí),隨著作用濃度的增長,呼吸抑制率迅速增強(qiáng),它對ASS中好氧微生物的半數(shù)效應(yīng)濃度(ECso)為527.39 mg-L-1。2. CeO2 NPs(1和10 mg.L-1)急性作用(1周期和20 d)對污水生物處理效果的影響：CeO2 NPs對ASS暴露1周期后,下個(gè)周期內(nèi)污染物去除規(guī)律變化研究結(jié)果表明,實(shí)驗(yàn)組S1 (1mg·L-1 CeO2NPs)和S2 (10mg·L-1 CeO2NPs)中有機(jī)物、氮與磷的去除規(guī)律與對照組S0 (0mg·L-1 CeO2NPs)基本一致。CeO2 NPs對ASS作用1個(gè)污泥齡(20 d)后,與S0相比,S1和S2出水水質(zhì)與污泥沉降性能沒有明顯差別。3. CeO2NPs慢性作用(150d)對污水生物處理效果的影響：Ce02NPs對ASS作用150 d,研究表明,S1和S2出水COD、NO2--N與SO一致。S1和S2出水NH4+-N相對于S0的1.63 mg·L-1分別升至4.33mg·L-1和6.26 mg·L-1；出水N03--N相較于S0的5.39 mg·L-1分別降至4.55 mg·L-1和3.91 mg·L-1。S1和S2中TN去除率分別從78.6%和78.3%降至71.3%和67.5%,出水TP分別由0.23 mg·L-1和0.29 mg·L-1上升至0.47 mg·L-1和0.58 mg-L-1,去除率分別下降了4.8%和6%。SO污泥容積指數(shù)(SVI)為82 mL·g-1,S1和S2的SVI值升至94 mL·g-1和109 mL·g1,污泥沉降性能變差。4.ASS中微生物群落結(jié)構(gòu)分析結(jié)果表明,CeO2NPs的慢性作用(150 d)未對ASS中微生物群落多樣性造成明顯影響,但對Proteobacteria菌群有抑制作用,對Actinobacteria菌群有促進(jìn)作,同時(shí)抑制與促進(jìn)的程度與CeO2 NPs濃度呈正相關(guān)。CeO2 NPs慢性作用使反硝化作用菌群豐度提升,降低了硝化功能菌群(Nitrosomonas和Nitrospire)和與污泥沉降相關(guān)的菌群Zoogloea豐度,且10 mg·L-1的抑制作用高于1 mg·L-1。CeO2 NPs慢性作用抑制了ASS中聚磷菌(PAOs)菌群豐度,相反,卻使系統(tǒng)中聚糖菌(GAOs) Defluviicoccus豐度提升。
[Abstract]:In recent years, nanomaterials (NMs) has been widely used in all aspects of human production and life because of its excellent physical and chemical properties. Mass production and use of NMs will inevitably lead to its release in the water environment. At present, the potential risk of NMs to human body and other organisms has been widely concerned by scholars, but there is still a lack of research on the possible risk of sewage biological treatment process. In this paper, cerium oxide nanoparticles (CeO2 NPs), which is one of the most promising market prospects, were selected to study the changes of effluent quality and microbial community structure in ASS after its acute and chronic effects on (ASS) in activated sludge system. the conclusions were as follows: the exposure toxicity test of 1.CeO2 NPs to aerobic microorganisms in ASS for 3 h showed that when the concentration of Ce02NPs was less than 100 mg.L-, the toxicity to microorganisms was weak. When the concentration was more than 100 mg-L-', the respiratory inhibition rate increased rapidly with the increase of action concentration, and the half effect concentration of (ECso) on aerobic microorganisms in ASS was 527.39 mg-L-1.2.. Effects of acute effects of CeO2NPs (1 and 10 mg.L-1) on biological treatment of sewage: after one cycle of CeO2NPs exposure to ASS, the results of pollutant removal in the next cycle showed that the organic compounds in S1 (1mg 路L-1 CeO2NPs) and S2 (10mg 路L-1 CeO2NPs) in the experimental group were organic matter in the experimental group S1 (1mg 路L-1 CeO2NPs) and S2 (10mg 路L-1 CeO2NPs). The removal regularity of nitrogen and phosphorus was basically the same as that of control group S0 (0mg 路L-1 CeO2NPs). After CEO 2 NPs treated ASS with one sludge age (20 days), there was no significant difference between S1 and S2 effluent quality and sludge sedimentation performance. 3. The effect of CeO2NPs chronic action (150d) on the biological treatment of sewage: the effect of Ce02NPs on ASS for 150d. The results showed that the COD,NO2--N of S1 and S2 effluent was consistent with that of SO. The NH4-N of S1 and S2 effluent increased to 4.33mg 路L-1 and 6.26 mg 路L-1, respectively, compared with S0, and the NH4-N of S1 and S2 effluent increased to 4.33mg 路L-1 and 6.26 mg 路L-1, respectively. The removal rates of TN in effluent N03 鈮，

本文編號：2510002