碱水解法处理脱水污泥的有机物溶出特性

碱水解法是一种有效的脱水污泥减量化方法,但碱水解法处理脱水污泥过程中产生的高浓度有机物溶液性质尚不明确。试验研究了脱水污泥在不同碱浓度处理下所得碱提取液中化学需氧量(TCOD)和溶解性化学需氧量(SCOD)、蛋白质、多糖、核酸的含量,明确了碱提取液中有机物组成,为实现碱水解液的综合利用,消除碱水解法用于污泥减量化过程中的二次污染提供了理论依据。研究结果表明,在碱处理浓度介于0.1¹ mol/L的条件下,提取物中SCOD浓度可达4 196.45 mg/L、SCOD/TCOD为90%、蛋白质浓度可达448.43 mg/L、多糖浓度为92.96 mg/L、核酸浓度为35.91 mg/L,且各指标整体碱浓度增大而增大。碱处理过程中脱水污泥中有机物发生了显著的溶解,污泥中的细菌被水解破碎。碱提取液具有将其作为生物处理设施外加碳源、动物饲料等潜在的利用价值。     

Comparative studies on fouling of homogeneous anion exchange membranes by different structured organics in electrodialysis

Five negatively charged organic compounds with different structures, sodium methane sulfonate (MS), sodium benzene sulfonate (BS), sodium 6-hydroxynaphthalene-2-sulfonate (NSS), sodium dodecyl sulfate (SDS), and sodium dodecyl benzene sulfonate (SDBS), were used to examine the fouling of an anion exchange membrane (AEM) in electrodialysis (ED), to explore the effect of molecular characteristics on the fouling behavior on the AEM and changes in the surface and electrochemical properties of the AEM. Results indicated that the fouling degree of the AEM by the different organics followed the order: SDBS?>?SDS?>?NSS?>?BS?>?MS. SDBS and SDS formed a dense fouling layer on the surface of the AEM, which was the main factor in the much more severe membrane fouling, and completely restricted the transmembrane ion migration. The other three organics caused fouling of the AEM by adsorption on the surface and /or accumulation in the interlayer of the AEM, and exhibited almost no influence on the transmembrane ion migration. It was also concluded that the organics with benzene rings caused more severe fouling of the AEM due to the stronger affinity interaction and steric effect between the organics and the AEM compared with organics with aliphatic chains.     

微波强化铁碳-双氧水体系处理填埋场渗滤液膜滤浓缩液研究

为了探讨微波(MW)/铁碳(Fe-C)/H_2O_2类芬顿反应对填埋场渗滤液膜滤浓缩液(简称"渗滤液浓缩液")中难降解有机物,系统研究了双氧水投量、Fe-C投量、初始pH值、微波输出功率和反应时间对浓缩液中有机污染物的去除规律,通过类比实验研究了MW/Fe-C/H_2O_2体系的反应协同作用;此外,采用紫外-可见和三维荧光光谱表征了浓缩液中溶解性有机物的分子结构变化;最后,利用SEM-EDS和XRD等表征对反应前后的Fe-C材料的催化机理进行了解析.结果表明,在双氧水投量为10 mL·L~(-1),Fe-C投量0.8 g·L~(-1),初始pH值为3,微波输出功率为450 W,反应时间为12 min时,其COD、腐殖质和色度的去除率达到了70.06%、94.61%和98.86%.与此同时,控制实验表明MW/Fe-C/H_2O_2具有较强的协同作用,且对有机物的降解效果远好于其他体系.经过MW/Fe-C/H_2O_2体系处理后,浓缩液中溶解性有机物的芳香性程度和腐殖质缩合度逐渐降低,并且腐殖质等大分子难降解有机物大幅去除,可生化性(BOD/COD值)也大幅提升.一方面,Fe-C材料包含了多种铁基氧化物等活性物质可与H_2O_2形成非均相芬顿反应;另一方面,在酸性条件下铁缓释淋滤产生的铁离子会与H_2O_2形成芬顿反应.并且,微波辐射作用可一定程度上强化上述过程,从而加速了有机物的去除.因此,MW/Fe-C/H_2O_2体系能够快速高效的对渗滤液浓缩液进行预处理,研究为高浓度有机废水的处理提供了借鉴.     

HLB-MR反应器直接处理城市污水及回收有机物

采用中空纤维超滤膜组件构建了高负荷生物絮凝-膜反应器（HLB-MR）,对其直接处理城市污水及回收有机物进行了研究.结果表明：当水力停留时间（HRT）为1.0h,固体停留时间（SRT）为0.2d时,该工艺可回收进水总COD的60.8%,据估算约有39%的进水总COD可通过中温厌氧消化转化为甲烷能源回收,有机物的甲烷转化率为活性污泥法剩余污泥的2倍以上,能实现污水中有机物的高效回收和利用;经过有机物回收后膜出水的COD能稳定保持在30mg/L左右,且出水中氮、磷营养物保有值均较高又不含固体杂质和病原体,可将其用作灌溉用水,实现水资源回用;SRT分别为0.2,0.6,1.0d时,反应器对胶体COD絮凝效率分别为81.9%、95.1%、96.8%,絮凝效率越高,膜污染越轻,良好的生物絮凝效果可有效减轻膜污染,保证工艺的稳定运行.     

利用电厂粉煤灰处理染料中间体废水

利用电厂粉煤灰，采用吸附法处理难生化降解的染料中间体二硝基氯化苯废水。结果表明，该法处理效果好，ＣＯＤＣｒ和色度去除率都很高，处理水可达标排放。而且此法处理成本大大低于活性炭吸附法。     

氯代有机污染物在厌氧条件下还原脱氯的研究进展

对氯代有机污染物在产甲烷和硫酸盐还原条件下还原脱氯的研究成果进行了综述 ,并介绍了国内外加速厌氧条件下还原脱氯的方法与成果以及缓释氢物质 (hydrogenreleasecompounds ,HRC)的工作原理与工程应用。此外 ,作者还对厌氧还原脱氯的机理和未来的研究方向进行了讨论和展望     

2005年夏季环渤海16条主要入海河流的污染状况

2005-07-01～2005-07-05对环渤海的黄河等16条主要河流的入海污染同步调查显示,13条河流断面的水质属于Ⅳ类以上,其中子牙新河等8条河流水质属于劣Ⅴ类,通过污染分担率分析,环渤海河流的首要污染物为石油类（11条河流）,其次为营养盐,高锰酸盐指数仅位居第3.采用综合营养状态指数法评价,大辽河、黄河等7条河流处于富营养状态,而小清河、蓟运河等7条河流处于重度富营养状态,可见环渤海河流的富营养化现象非常严重.有机污染物的调查显示,16条河流断面采样点TOC的平均值为16 .41 mg/L,高锰酸盐指数的平均值为6 .04 mg/L,其中易降解有机物所占比例平均为15 .61%,表明虽然环渤海16条河流中的化学需氧有机物质的污染严重,但总有机物的入海通量更大,这一点必须引起足够的重视.     

渗滤液场内处理的有机物去除特征和植物毒性评价

摘要：以3种不同处理水平的渗滤液为研究对象,从有机物去除特征和植物毒性角度研究通过渗滤液循环回灌和终场覆盖层灌溉2个单元处理生活垃圾填埋场渗滤液的可行性.结果表明,循环回灌对老港渗滤液中的小分子量亲水性物质类(HyI)有机物去除效果较好,去除率为91.2%;终场覆盖层灌溉对循环回灌出水中的高分子量腐殖质类(HS)有机物去除效果较佳,去除率为85.7%;两者串联组合的场内循环处理工艺对老港渗滤液中的溶解性有机物(DOM)去除 率高达96.9%,且对HS和HyI均具较高的去除效果,去除率分别为96.6%和97.0%;循环回灌和覆盖层灌溉这2个处理单元还具有梯级降低渗滤液植物毒性的作用.     

Global environmental cycling of γ-HCH and DDT in the 1980s – A study using a coupled atmosphere and ocean general circulation model

A coupled atmosphere–ocean general circulation model, ECHAM5-MPIOM, was used to study the multicompartmental cycling and long-range transport of persistent and semivolatile organics. Multiphase systems in air and ocean are covered by submodels for atmospheric aerosols, HAM, and marine biogeochemistry, HAMOCC5, respectively. The model, furthermore, encompasses 2D surface compartments, i.e. top soil, vegetation surfaces and sea-ice. The total environmental fate of γ-hexachlorocyclohexane (γ-HCH, lindane) and dichlorophenyltrichloroethane (DDT) in agriculture were studied.DDT is mostly present in the soils, the water-soluble γ-HCH in soils and ocean. DDT has the longest residence time in almost all compartments. Quasi-steady state with regard to substance accumulation is reached within a few years in air and vegetation surfaces. In seawater the partitioning to suspended and sinking particles contributes to the vertical transport of substances. On the global scale deep water formation is, however, found to be more efficient. Up to 30% of DDT but only less than 0.2% of γ-HCH in seawater are stored in particulate matter.On the time scale studied (1 decade) and on global scale substance transport in the environment is determined by the fast atmospheric circulation. The meridional transport mechanism, for both compounds, is significantly enhanced by multi-hopping. Net meridional transport in the ocean is effective only regionally, mostly by currents along the western boundaries of Africa and the Americas. The total environmental burdens of the substances experience a net northward migration from their source regions, which is more pronounced for DDT than for γ-HCH. Due to the application distribution, however, after 10 years of simulation 21% of the global environmental burden of γ-HCH and 12% of DDT have accumulated in the Arctic.     

A comparison of exposure methods for SPME-based bioavailability estimates

The ability of polydimethlysiloxane coated solid phase microextraction (SPME) fibers to predict bioavailability has been documented for a number of species and compounds. There are also a variety of established methods for establishing SPME-based bioavailability estimates; however, factors such as time until equilibrium and exposure regimen could affect fiber concentrations and have not yet been thoroughly tested. Exposure time may influence SPME fiber concentrations at equilibrium. Co-exposure of the fibers with different animals or the invertebrate species used could yield different estimates than those acquired using a shaker table system to achieve equilibrium between the sediment and SPME fibers. The current study examined the effects of time and exposure method (shaker table versus co-exposure with test species) on SPME fiber concentrations for two hydrophobic compounds: permethrin and p,p′-dichlorodiphenyldichloroethylene (DDE). An additional experiment with permethrin determined whether animal densities or fiber number influenced fiber concentrations. There were significant differences between the time required for SPME fibers to reach equilibrium when co-exposed with different species or separately, but fiber concentrations at equilibrium among treatments for both compounds were similar. Furthermore, among the 12 variations in species and fiber densities, there were no significant differences among treatments indicating that neither the route of exposure, animal density, nor fiber volume influenced SPME fiber estimates. This demonstrated that SPME fiber concentrations at equilibrium were not affected by exposure conditions, increasing their versatility in environmental assessments.