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201.
202.
味精废水中重金属及金属污染对处理利用的影响 总被引:1,自引:0,他引:1
本文应用等离子光谱(ICP)测试三个厂家味精生产废水中21种金属元素的水平,其中金属元素的总水平分别达19192mg.l^-1,3190mg.l^-1和3161mg.l^-1,对照国内外有关的四项水质标准,三厂家味精生产废水中存在着Fe,Zn等多种重金属或其他金属元素严重超标现象,味精生产废水对青芋存在急性毒性,24,48,72和96h的半致死味精废水浓度LC50分别为6.9%,3.2%,2.5% 相似文献
203.
复极性固定床电解槽内电极电位的分布 总被引:25,自引:1,他引:25
本文通过设计独特的测量和检验实验装置,对复极性固定床电解槽内的电极电位进行了测试。发现了槽内反应的动力就是槽内粒子与溶液的电位之差,可通过调节它的变化来控制反应的进行。 相似文献
204.
在气相色谱和色谱-质谱分析的基础上,对以六六六为原料生产多氯苯的两种工艺的产品及废渣进行了分析。结果表明:伴随多氯苯的生成,尚有多种氯化物产生。在水解生产工艺中,产品和废渣中有微量PCDDs和PCDFs,但产品中还有少量PCBs。在热解工艺中,废渣内发现大量的PCBs,PCDDs和PCDFs,最毒的异构体,2,3,7,8-TCDD含量高达24ppm。 相似文献
205.
浙江墩头盆地横山组孢粉化石的发现及其地层意义 总被引:1,自引:0,他引:1
浙江墩头盆地红色岩层中上部首获丰富的以Cassopllis为主(58.39—62.54%)伴有Exesipollenites(15.21—15.84%),Hsuisporites(0.56—0.62%),Cicatricosisporites(0—0.31%)等孢粉化石。该孢粉组合特征既与国内外晚侏罗世孢粉组合面貌差别较大,又与早白垩世中晚期孢粉组合面貌存在明显差异,显示了早白垩世早期孢粉组合的色彩。笔者认为这套红色岩层应归早白垩世早期横山组为宜。 相似文献
206.
研究了超声场降解水溶液中叔丁醇的行为,并探讨了反应动力学模式。实验表明.在本实验条件下超声波降解叔丁醇能够达到较好的降解效果。叔丁醇的去除率随着超声辐射时间的延长而提高,在频率为20kHz、功率为1500W的超声场下,作用80min能够达到90%左右的去除率。反映体系的降解速率随着反应温度的提高而升高,随着初始浓度的增大而降低:反应体系的pH值对叔丁醇的降解率影响不大:溶液中溶解气体的种类对降解效果有一定影响。反应速率常数按照由快到慢的顺序为ko2〉k未作处理〉kN2。在一定的初始浓度条件下,超声波降解叔丁醇的反应符合假一级反应动力学模式。 相似文献
207.
The partition coefficients of organochlorine pesticides (OCPs) between the organic matter of Taichung soil and water (Koc) were evaluated with batch-type experiments. The partition coefficients of OCPs between Aldrich humic acid and water (Kdoc) were estimated with solubility enhancement method as well. In this study, the Kocs of aldrin, heptachlor, and p,p′-DDT are greater than their Kdocs, and the relationship of dieldrin and heptachlor epoxide are opposite. The variations of partition coefficients are discussed. For predicting Kdoc, a log-log regression relationship of Kdoc and Kow is determined. 相似文献
208.
Effect of pH on phosphine production and the fate of phosphorus during anaerobic process with granular sludge 总被引:6,自引:0,他引:6
The effect of pH on phosphine formation during anaerobic cultivation of granular sludge was investigated. The sludge was taken from full-scale anaerobic reactors treating brewery wastewater. Acetate and phosphate were used as the carbon source and phosphorus source respectively. After 10 days cultivation in the dark, results showed that acidic conditions were more favorable for free phosphine production. At pH 5, the optimum concentration 86.42 ng PH3 m-3 of free phosphine was obtained. The level at pH 7 was reduced to 18.53 ng PH3 m-3, about 1/5 of the maximum. The maximum concentration of matrix-bound phosphine of 3.30 ng PH3 kg-1 wet sludge was achieved at pH 6. More than 83% of the total phosphine was matrix-bound phosphine, which accounted for 0.003-0.009 per thousand of the phosphate removal, while free phosphine comprised 0.00002-0.001 per thousand of the phosphate removal. Most of the phosphorus removal from solution was turned into chemical precipitation or was adsorbed by sludge. The mechanism of the phosphate reduction-step in the formation of phosphine production is still unknown. The promotion of phosphine formation by low pH is compatible with an acidic bio-corrosion mechanism of metal particles in the sludge or of metal phosphides which form phosphine at low pH. 相似文献
209.
In order to search for locally available and untried biomaterials in China with high removal capacity of heavy metals from wastewater, the feasibility of Spirulina maxima as biosorbent for lead removal and recovery from aqueous solution was investigated. The lead biosorption was studied by using intact biomass and pretreated biomass of S. maxima. The effects of operational conditions (e.g. pH, contact time, biomass concentration etc.) on lead biosorption were investigated. The biosorption was solution pH dependent and the maximum adsorption was obtained at a solution pH of about 5.5. The adsorption equilibrium was reached in 60 min. The biosorption followed the Freundlich isotherm model. The maximum removal ratios of lead were about 84% in intact biomass and 92% in pretreated biomass. The lead adsorbed could be desorbed effectively by 0.1 M nitric acid, EDTA and hydrochloric acid. The results in this study indicated that pretreated biomass of S. maxima was a promising candidate for removing lead from wastewater. 相似文献
210.
Occurrence and behavior of wastewater indicators in the Santa Ana River and the underlying aquifers.
The occurrence and behavior of wastewater indicator compounds in the Santa Ana River (SAR) water and the underlying aquifer recharged by the SAR has been studied. The SAR contains a high proportion of tertiary treated wastewater effluents, up to 100% during summer and fall. The following water quality parameters were quantified: four specific wastewater indicator compounds, ethylene diaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), a naphthalene dicarboxylate (NDC) isomer, alkylphenol polyethoxy carboxylates (APECs), and selected haloacetic acids (HAAs), nitrate, dissolved oxygen (DO), DOC, total carbohydrate, and phenolic substances. Statistical analysis indicated that normal distribution was adequate to describe the probability distribution of the constituents in most cases. In the river, the concentrations of wastewater indicator compounds decreased as the fraction of storm runoff increased. EDTA and NDC were detected in a monitoring well near the river and in two production wells 1.8 and 2.7 km down gradient with little apparent attenuation. By contrast, NTA, APECs, bromochloro- and dibromoacetic acids appeared to be attenuated significantly during infiltration of river water and groundwater transport. 相似文献