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741.
在pH<1的溶液中,用甲基异丁酮(MIBK)与磷酸三丁酯(TBP)混合作为萃取剂,萃取废水中的铬时,六价铬的分配比为108.6,而三价铬几乎不被萃取。用原子吸收分光光度计测定有机相中的六价铬具有很好的选择性,且干扰少,灵敏度高。工作曲线的最佳浓度范围是:0.04~4.00mg/L。  相似文献   
742.
对宁波市7家市属医院废水进行了一年4次的连续监测,发现7家医院废水均严重超标.造成医院废水严重超标的原因有4个方面.同时还探讨了监测规范中存在的三个主要问题,提出了解决办法.文章对南方城市的医院废水监测具有一定的典型性.  相似文献   
743.
A waste paper sludge-derived heterogeneous catalyst(WPS-Fe-350) was synthesized via a facile method and successfully applied for the degradation of Orange Ⅱ in the presence of oxalic acid under the illumination of ultraviolet light emitting diode(UV-LED) Powder X-ray diffraction,Fourier-transform infrared spectroscopy,scanning electronic microscopy and N2 sorption isotherm analysis indicated the formation of α-Fe2O3 in the mesoporous nanocomposite.The degradation test showed that WPS-Fe-350 exhibited rapid Orange Ⅱ(OⅡ) degradation and mineralization in the presence of oxalic acid under the illumination of UV-LED.The effects of p H,oxalic acid concentration and dosage of the catalyst on the degradation of OⅡ were evaluated,respectively.Under the optimal conditions(1 g/L catalyst dosage,2 mmol/L oxalic acid and p H 3.0),the degradation percentage for a solution containing 30 mg/L OⅡ reached 83.4% under illumination by UV-LED for 80 min.Moreover,five cyclic tests for OⅡ degradation suggested that WPS-Fe-350 exhibited excellent stability of catalytic activity.Hence,this study provides an alternative environmentally friendly way to reuse waste paper sludge and an effective and economically viable method for degradation of azo dyes and other refractory organic pollutants in water.  相似文献   
744.
Waste of polystyrene was converted into a cation exchange resin and was used for the removal of lead and cadmium metals from aqueous solution. Wastes consisting of coffee cups were crushed into small pieces and immersed into a solution of sulfuric acid in order to attach sulfonic group to polymer chain, these groups are responsible for the exchange properties of the modified plastic. The cation exchange capacity (CEC) was determined and was comparable to commercial exchangers. The adsorption isotherms of resin with synthetic wastewater containing lead and cadmium ions were tested. Adsorption analysis results obtained at various concentrations showed that the adsorption pattern on the resin followed Langmuir isotherms.  相似文献   
745.
The purpose of this study was to establish a fuel process for an advanced power generation system in which hydrogen-rich synthesis gas, as the fuel for the molten carbonate fuel cell (MCFC), can be extracted from biomass via gasification and reforming technologies. Experiments on waste wood gasification were performed using a bench-scale gasification system. The main factors influencing hydrogen generation in the noncatalytic process and in the catalytic process were investigated, and temperature was identified as the most important factor. At 950°C, without employing a catalyst, hydrogen-rich synthesis gas containing about 54 vol% hydrogen was extracted from feedstock with appropriately designed operation parameters for the steam/carbon ratio and the equivalence ratio. However, by employing a commercial steam reforming catalyst in the reforming process, similar results were obtained at 750°C.  相似文献   
746.
The characteristic levels of heavy metals (Cd, Cr, Cu, Pb, Ni and Zn) of soil profiles of automobile mechanic waste dumps were studied. The concentration of heavy metals decreased with the depth of the profile and lateral distance from the dumpsites. The levels found in this study exceeded background concentrations and limits for agricultural and residential purposes. The distribution pattern of heavy metals in the soil profiles were in the following order Pb > Zn > Cu > Cd > Ni > Cr. The mechanic waste dumps represent potential sources of heavy metal pollution to environment. The elevated levels of heavy metals in these soil profiles constitute a serious threat to both surface and groundwater.  相似文献   
747.
Most Taiwanese farmers usually blend rice straws into the soil after harvest. However, rice straws possess great thermal energy, which can be used to produce refuse-derived fuel (RDF-5). As Taiwan faces energy shortage, the development benefits of the RDF-5 industry are tempting. This study employs the Hotelling model to design the locations and the optimal numbers of RDF-5 plants. From the technology and material supply point of view, turning waste rice straws into RDF-5 is feasible in Taiwan. Nevertheless, from the business operation perspective, even if the RDF-5 plant is willing to lower its profit rate, its selling price is still hard to compete with imported RDF-5. If the Taiwanese government decides to pursue RDF-5 as an alternative energy, they might need to take a step further to subsidize entrepreneurs or provide appropriate tax benefits. Otherwise, the RDF-5 industry is hard to survive in Taiwan.  相似文献   
748.
河北省河流污染主要来自城市生活污水和工业废水。河北省现有污水处理厂共有20座,日处理能力173.9万吨,处理率38%。省政府已出台政策,鼓励污水处理向企业化发展,吸纳社会资金,引进国外技术与资金。河北省年排放工业废水10.2亿吨,处理达标率80%,积极推行清洁生产,减少污染物的排放量,由末端治理走向全过程控制。  相似文献   
749.
采油污水必须经过处理达到油田注水水质控制指标才能回注。华北石油管理局第二采油厂岔南联合站建成投产后,采取了选用合适的化学药剂,改善加药方法等措施,使岔南联合站污水水质得到较大改善,达到了油田注水水质控制指标,并同时收到了减少电耗和化学药剂使用量,节约成本的效果。环境效益和经济效益都十分显著。本文介绍了该站污水处理系统技术改造的试验过程及效果。  相似文献   
750.
钻井废水的处理现状与展望   总被引:4,自引:1,他引:4  
油气井钻探过程中产生大量钻井废水,会对环境产生污染。本文介绍了钻井废水的来源、组成及其对环境的影响,着重介绍了目前钻井废水的处理工艺、方法和处理剂,并对钻井废水处理技术的发展进行了展望。  相似文献   
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