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1.
王丹  马玉龙 《环境保护科学》2009,35(4):38-39,59
利用微生物法对红霉素膜浆中的红霉素药物残留量进行测定,红霉素残留量为265.88μg/mL。再通过调节pH值不同对膜浆残留红霉素的降解进一步研究。利用盐酸将膜浆的pH值调到2时,残留红霉素浓度为15.03μg/mL;降解率为94.35%。  相似文献   

2.
土壤渗滤处理技术研究现状与进展   总被引:25,自引:0,他引:25  
土壤渗滤处理技术在我国广大地区有很好的适应性和可行性,将有很好的发展前景。该文论述了土壤渗滤技术的发展历史和现状,并对近十年来该技术的实验室模拟、机理研究、具体应用实践和运行模式的优化等方面进行了概括分析与总结   相似文献   

3.
土壤含水层处理去除可吸附有机卤化物的试验研究   总被引:14,自引:0,他引:14  
研究了土壤含水层处理工艺对典型城市二级出水以可吸附有机卤化物表征的有机物的去除效果。投加24mg/l臭氧预处理后,再经好氧含水层处理可去除约32%的AOX,厌氧柱进水中投加各80mg/l葡萄糖和谷氨酸,运行稳定性,通过共谢作用,可去除约55%的AOX。  相似文献   

4.
土著嗜油微生物对土壤中石油类污染物的降解性研究   总被引:1,自引:0,他引:1  
本研究从长期受石油污染的土壤中筛选了土著嗜油菌,通过盆栽实验研究了土著菌对石油的降解效果,并探讨了化肥、沼渣对微生物活性的影响及施用菌液、营养液对降解效果的影响。  相似文献   

5.
    
Soil contamination with tetrabromobisphenol A(TBBPA) has caused great concerns;however, the presence of heavy metals and soil organic matter on the biodegradation of TBBPA is still unclear. We isolated Pseudomonas sp. strain CDT, a TBBPA-degrading bacterium, from activated sludge and incubated it with ~(14)C-labeled TBBPA for 87 days in the absence and presence of Cu~(2+)and humic acids(HA). TBBPA was degraded to organic-solvent extractable(59.4% ± 2.2%) and non-extractable(25.1% ± 1.3%) metabolites,mineralized to CO_2(4.8% ± 0.8%), and assimilated into cells(10.6% ± 0.9%) at the end of incubation. When Cu~(2+)was present, the transformation of extractable metabolites into non-extractable metabolites and mineralization were inhibited, possibly due to the toxicity of Cu~(2+)to cells. HA significantly inhibited both dissipation and mineralization of TBBPA and altered the fate of TBBPA in the culture by formation of HA-bound residues that amounted to 22.1% ± 3.7% of the transformed TBBPA. The inhibition from HA was attributed to adsorption of TBBPA and formation of bound residues with HA via reaction of reactive metabolites with HA molecules, which decreased bioavailability of TBBPA and metabolites in the culture. When Cu~(2+)and HA were both present, Cu~(2+)significantly promoted the HA inhibition on TBBPA dissipation but not on metabolite degradation. The results provide insights into individual and interactive effects of Cu~(2+)and soil organic matter on the biotransformation of TBBPA and indicate that soil organic matter plays an essential role in determining the fate of organic pollutants in soil and mitigating heavy metal toxicity.  相似文献   

6.
赵庆良  薛爽  王丽娜 《环境科学》2007,28(8):1726-1731
在实验室通过模拟土壤柱研究了人工地下水回灌过程中溶解性有机物的去除及其三卤甲烷生成势和三卤甲烷生成活性的变化.利用XAD树脂将回灌水中的溶解性有机物分为3个部分:疏水性有机酸、过渡亲水性有机酸和亲水性有机物.疏水性有机酸的三卤甲烷生成活性高于过渡亲水性有机酸和亲水性有机物.土壤含水层处理(SAT)对亲水性有机物的去除率为68.51%,对疏水性有机酸和过渡亲水性有机酸的去除率分别为58.64%和41.86%.经SAT系统处理后,溶解性有机物及各有机组分的三卤甲烷生成势减少,而三卤甲烷生成活性升高.疏水性有机酸是生成三卤甲烷的主要有机组分.亲水性有机物在SAT系统进水中的三卤甲烷生成活性较低,但由于含量高,三卤甲烷生成势也较大.而过渡亲水性有机酸由于含量和三卤甲烷生成活性较低,三卤甲烷生成势也较低.  相似文献   

7.
根据我国农村污水分散排放的特点,结合土壤渗滤系统所具有的设备简单、投资少、操作管理方便、能耗低、净化效果良好等特点,分析了土壤渗滤系统的净化机理和影响因素,并对系统运行中污染物迁移转化模型和主要应注意的问题进行了探究。  相似文献   

8.
喹啉及其衍生物微生物降解研究进展   总被引:9,自引:0,他引:9  
喹啉类氮杂环化合物在水、土壤环境中普遍存在,受其污染的水、土壤环境生物修复是目前环境治理领域的重要课题。介绍了近年来喹啉类氮杂环化合物微生物降解的国内外研究进展,主要包括可利用喹啉类氮杂环化合物作为碳源、氮源和能源的微生物资源、微生物降解的有氧代谢和无氧代谢两大途径,以及喹啉类化合物的降解动力学。在此基础上,提出了需要进一步研究的方向。  相似文献   

9.
红霉素菌渣是宝贵的资源,但却含有少量的红霉素残留,潜在引发环境细菌耐药的风险,被国家定义为危险废物。文章采用厌氧发酵技术处理红霉素菌渣,拟借助微生物作用降低抗生素残留并制取生物燃气,文中考察了红霉素残留随厌氧发酵过程的降解规律。研究发现:中温(35℃)发酵、接种比为0.4、含固率为8%时,单位池容产气率最高,红霉素菌渣的厌氧发酵处理是可行的。此外,在发酵的10 d后,红霉素降解率达到94%以上,日相对降解率与发酵液pH相关,pH越小降解速率越大,pH越接近中性,降解越缓慢。同时得到其降解过程与厌氧发酵产气量无明显相关性。该文为红霉素菌渣安全资源化提供了基础数据。  相似文献   

10.
    
Heterogeneous photocatalytic reaction has been generally applied for degradation of toxic contaminants. Degradations of a compound using the same kind of catalyst that was synthesized differently are commonly found in literature. However, the reported degradation intermediates are normally inconsistent. This issue is especially important for the degradation of toxic compounds because intermediates may be more toxic than their parent compounds and understanding the reason is necessary if appropriate catalysts are to be designed. This work systematically compares the photocatalytic degradation of diuron, a toxic recalcitrant herbicide, on two forms of zinc oxide (ZnO), i.e., conventional particles with zinc- and oxygen-terminated polar surfaces as the dominating planes, and nanorods with mixed-terminated nonpolar surfaces. Experimental and theoretical results indicate that both the rate of reaction and the degradation pathway depend on the adsorption configuration of diuron onto the surface. Diuron molecules adsorb in different alignments on the two surfaces, contributing to the formation of different degradation intermediates. Both the aliphatic and aromatic sides of diuron adsorb on the polar surfaces simultaneously, leading to an attack by hydroxyl radicals from both ends. On the other hand, on the mixed-terminated surface, only the aliphatic part adsorbs and is degraded. The exposed surface is therefore the key factor controlling the degradation pathway. For diuron degradation on ZnO, a catalyst confined to mixed-terminated surfaces, i.e., ZnO nanorods, is more desirable, as it avoids the formation of intermediates with potent phytotoxicity and cytogenotoxicity.  相似文献   

11.
采用富集培养法,从拟除虫菊酯农药厂废水排放口的活性污泥中分离到1株菊酯农药高效降解菌P-01.经形态、生理生化特征及16S rDNA序列分析,初步鉴定其为无色杆菌属(Achromobacter sp.).响应曲面法优化菌株P-01的降解条件,其降解最优条件为31.4 ℃、初始pH 7.6和接种量0.4 g · L-1,在此条件下,该菌株培养7 d对50 mg · L-1溴氰菊酯、氰戊菊酯、高效氯氰菊酯、高效氟氯氰菊酯和高效氯氟氰菊酯的降解率分别达到98.9%、92.2%、91.0%、85.1%和77.3%,且降解过程满足一级动力学方程模型,降解半衰期(T1/2)分别为1.3、1.8、2.0、2.5和3.0 d.该菌株能以溴氰菊酯为唯一碳源,且高度耐受并快速降解溴氰菊酯,在溴氰菊酯浓度为100~500 mg · L-1时依然保持较高的降解率.降解途径分析结果表明,该菌株通过酯键断裂将溴氰菊酯降解产生α-羟基—3-苯氧基苯乙腈和3-苯氧基苯甲醛,而后进一步氧化分解生成2-羟基—4-甲氧基二苯甲酮和邻苯二甲酸单酯.  相似文献   

12.
溶解性有机质(DOM)的荧光物质是一种较好的示踪剂,用于鉴别DOM的来源及其在水文系统中的地球化学行为.该物质在岩溶水系统中的研究较少,并且要作为潜在示踪剂,系统中有很多因素影响其光谱信息.实验选取一典型岩溶流域,通过三维荧光光谱技术(EEMs)和平行因子分析(PARAFAC),结合水化学数据分析,揭示DOM荧光物质在不同岩溶含水空间的组成和转化关系,刻画流域尺度DOM的来源,探讨水化学因素对DOM荧光物质转移的影响机制.结果表明,流域外源地表水和岩溶地表水中的DOM以类蛋白色氨酸为主,浅层岩溶水和深层岩溶水以类蛋白色氨酸和酪氨酸为主.荧光指数(FI)、生物指数(BIX)和腐殖化指数(HIX)的综合分析认为,浅层岩溶水和深层岩溶水的DOM主要来自于内源微生物分解,岩溶地表水和外源地表水的DOM既有陆源输入又有内源微生物分解,且内源贡献占有较大比例.受岩溶水化学参数的影响,3种荧光物质具有明显的分异特征:类酪氨酸物质对Ca~(2+)和HCO_3~-具有较强的适应性,在岩溶水中存在的比例比较大.类色氨酸物质则相反,类富里酸物质则与TDS、浊度、Cl~-、SO_4~(2-)等呈现极显著正相关关系.流域上游浅层岩溶水中的DOM主要来自内源.出露地表以后,其有机质同时来自内源和外源输入.在流域下游渗入深层岩溶地下水以后,DOM逐渐向低芳香烃有机质化合物转化,大分子DOM逐渐减少,荧光强度减弱.主成分分析(PCA)提取出3个主成分,分别为反映岩溶水渗滤、转化、水流条件的水体矿化指标,反映土壤淋滤和自然渗滤关系的TOC、NO_3~-及类蛋白质指标,以及反映岩溶水系统水化学、生物化学过程的Ca~(2+)、HCO_3~-、荧光指数和类富里酸指标.此外研究还认为,总荧光强度,类富里酸物质和类蛋白物质可以分别作为岩溶水快速渗流、转化及岩溶含水层脆弱性的示踪剂.研究结果有助于认识岩溶地下水DOM的生物地球化学循环,进行岩溶系统有机污染控制,为岩溶水系统中物质的地球化学过程表征提供一种新的工具.  相似文献   

13.
废水中染料的TiO_2光催化氧化降解机理研究现状   总被引:1,自引:0,他引:1  
系统论述了废水中TiO2光催化氧化降解染料的机理、动力学机制、染料的反应活性、研究中间降解产物的方法和结果等的研究现状,指出了目前研究中最大难点是分析手段的不足,对此提出了自己的看法,这为今后实际废水处理工艺过程中起到指导控制作用。  相似文献   

14.
采用厌氧-好氧-混凝工艺,对垃圾焚烧厂高DOM渗滤液进行处理,当进水ρ(CODCr)平均值为10 800 mg/L时,出水ρ(CODCr)平均值可达208 mg/L;同时,着重针对各工艺单元出水DOM不同分子质量分布区间的ρ(CODCr)以及DOM组成成分的变化进行了研究.结果表明:该处理工艺对DOM分子质量<50 ku的有机物去除率均可达到94.7%以上,而对分子质量<2 ku的有机物的去除率可达99.0%;对渗滤液DOM组成成分〔腐殖酸(HA)、富里酸(FA)和亲水性有机质(HyI)〕的去除率均达到90.0%以上,表明该组合工艺用于处理垃圾焚烧厂渗滤液是可行的.   相似文献   

15.
    
Field studies were conducted to investigate the advanced treatment of the municipal secondary effluent and a subsequent artificial groundwater recharge at Gaobeidian Wastewater Treatment Plant, Beijing. To improve the secondary effluent quality, the combined process of powdered activated carbon adsorption, flocculation and rapid sand filtration was applied, which could remove about 400 dissolved organic carbon (DOC) and 70% adsorbable organic halogens. The results of liquid size exclusion chromatography indicate that in the adsorption unit the removed organic fraction was mainly low molecular weight compounds. The fractions removed by the flocculation unit were polysaccharides and high molecular weight compounds. The retention of water in summer in the open recharge basins resulted in a growth of algae. Consequently, DOC increased in the polysaccharide and high molecular weight humic substances fraction. The majority of the DOC removal during soil passage took place in the unsaturated area. A limited reduction of DOC was observed in the aquifer zone.  相似文献   

16.
环境中灭幼脲类农药的监测方法及其迁移转化情况   总被引:4,自引:0,他引:4  
综述了环境中灭幼脲类农药的各种监测分析方法,并对各种监测分析方法的优缺点作了评述;同时,总结了灭幼脲类农药在环境中的迁移情况和各种降解途径,分析了影响其降解情况的各种因素。   相似文献   

17.
李心宏 《上海环境科学》1992,11(4):22-25,33
阐述了在土地处理制革废水过程中污染物的去除机理。其主要方式是物理、化学和生物的去除,并给出在一定土壤状况下去除机理的综合模型。  相似文献   

18.
  总被引:1,自引:0,他引:1  
High performance size exclusion chromatography (HPSEC) is used in water quality research primarily to determine the molecular weight distribution of the dissolved organic matter (DOM), but by applying peak fitting to the chromatogram, this technique can also be used as a tool to model and predict DOM removal. Six low specific UV absorbance (SUVA) source waters were treated using coagulation with alum and both the source and treated water samples were analysed using HPSEC. By comparing the molecular weight profiles of the source and treated waters, it was established that several DOM components were not effectively removed by alum coagulation even after high dosage alum treatment. A peak-fitting technique was applied based on the concept of linking the character (molecular weight profile) of the recalcitrant organics in the treated water with those of the source water. This was then applied to predict DOM treatability by determining the areas of the peaks which were assigned to removable organics from the source water molecular weight profile after peak fitting, and this technique quantified the removable and non-removable organics. The prediction was compared with the actual dissolved organic carbon (DOC) removal determined from jar testing and showed good agreement, with variance between 2% and 10%. This confirmed that this prediction approach, which was originally developed for high SUVA waters, can also be applied successfully to predict DOC removal in low SUVA waters.  相似文献   

19.
通过土壤柱实验,研究了土壤含水层处理工艺对污水处理厂二级处理出水的处理效果。初步讨论了土壤含水层处理工艺对各种污染物的去除机理,并评价了不同回用途径再生水对人体的健康风险。研究结果表明:土壤含水层处理工艺能够有效去除二级处理出水中的有机物和重金属离子,对大肠菌和粪大肠菌的去除率大于99.9%。健康风险评价结果显示:再生水的健康风险主要来自致癌物质,终生致癌风险在10-6数量级,而非致癌物质的健康危害风险在10-9数量级。  相似文献   

20.
    
AgCl/ZnO/g-C3N4, a visible light activated ternary composite catalyst, was prepared by combining calcination, hydrothermal reaction and in-situ deposition processes to treat/photocatalyse tetracycline hydrochloride (TC-HCl) from pharmaceutical wastewater under visible light. The morphological, structural, electrical, and optical features of the novel photocatalyst were characterized using scanning electron microscopy (SEM), UV-visible light absorption spectrum (UV–Vis DRS), X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and transient photocurrent techniques. All analyses confirmed that the formation of heterojunctions between AgCl/ZnO and g-C3N4 significantly increase electron-hole transfer and separation compared to pure ZnO and g-C3N4. Thus, AgCl/ZnO/g-C3N4 could exhibit superior photocatalytic activity during TC-HCl assays (over 90% removal) under visible light irradiation. The composite could maintain its photocatalytic stability even after four consecutive reaction cycles. Hydrogen peroxide (H2O2) and superoxide radical (·O2) contributed more than holes (h+) and hydroxyl radicals (·OH) to the degradation process as showed by trapping experiments. Liquid chromatograph-mass spectrometer (LC-MS) was used for the representation of the TC-HCl potential degradation pathway. The applicability and the treatment potential of AgCl/ZnO/g-C3N4 against actual pharmaceutical wastewater showed that the composite can achieve removal efficiencies of 81.7%, 71.4% and 69.0% for TC-HCl, chemical oxygen demand (COD) and total organic carbon (TOC) respectively. AgCl/ZnO/g-C3N4 can be a prospective key photocatalyst in the field of degradation of persistent, hardly-degradable pollutants, from industrial wastewater and not only.  相似文献   

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