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101.
102.
重铬酸钾法测定废水COD条件改进的研究 总被引:3,自引:0,他引:3
本提出用CuSO4作催化剂,在H2SO4-H2PO4溶液中,重铬酸钾回流测定废水COD的方法,实验表明,最佳测定条件为:CuSO4浓度为7×10^-2mol.L^-1(混酸溶液):H2SO4:H3PO4=5:1(体积比)回流时间2h,通过与标准方法对比,测定结果满意,本方法的优点是:不需用贵重金试剂Ag2SO4,改用CuSO4作催化剂,精密度高,准确性好,具有一定的实用价值。 相似文献
103.
利用黄钾铁矾类矿物形成过程预处理高浓度含硫废水 总被引:1,自引:0,他引:1
利用黄钾铁矾类矿物形成过程对某高浓度工业含硫废水进行预处理,除去一定量的SO42-,使溶液中低价态的硫继续转化成SO42-,再进行氧化处理。采取二次沉淀除去溶液中更多的SO42-,大大降低了该水样的COD值。通过实验得出沉淀的最佳工艺条件为pH值为2.50~3.20,氯化铁晶体(FeCl3.6H2O)最佳投入量为50g/L。经过两次黄钾铁矾类矿物沉淀过程,该废水COD的去除率达到85.29%,结合H2O2的氧化处理,COD去除率可达96%。为高浓度含硫废水进入生化处理前的预处理提供了实验依据。 相似文献
104.
生物矿化针铁矿对造纸废水的吸附和热解吸研究 总被引:1,自引:0,他引:1
利用生物矿化针铁矿对造纸废水进行吸附实验,对吸附动力学、影响因素、以及吸附等温线等进行了研究,通过DTA和XRD研究了不同煅烧温度条件下生物矿化针铁矿的物质形态变化,分析了不同再生条件对生物矿化针铁矿的吸附容量的影响。结果表明:生物矿化针铁矿对造纸废水中的污染物吸附速度较快,具有良好的吸附性能;生物矿化针铁矿吸附污染物后经过煅烧可以实现再生,经310℃煅烧后的第一次再生吸附率为原针铁矿的97.3%,多次加热再生后仍然具有很高的吸附能力。 相似文献
105.
采用壳聚糖对酸性蓝黑B模拟废水进行处理,研究了溶液的酸度、吸附时间、溶液的初始浓度和溶液温度等对吸附效率的影响。结果表明,壳聚糖对酸性蓝黑B具有优良的吸附效果,在溶液初始浓度小于400 mg/L,pH=3.5~6,温度约为30~40℃,吸附处理30~40 m in,COD去除率可达90%以上。 相似文献
106.
Study on numerical simulation of organic pollutant transport in groundwater northwest of Laixi 下载免费PDF全文
The construction and hydrogeological area in the low hill, which is northwest of Laixi City and in the east of Shandong Province more precisely, is one of Dagu River’s groundwater source. Regarding COD as the typical pollutant according to general situation of groundwater pollution in aforementioned area, a three-dimensional advection-dispersion model was established to simulate the transport of organic pollutants under two accident conditions. In addition, the effect of corresponding dispersity was analyzed. The results show that COD transport is mainly in accordance with the direction of groundwater flow, pollutant concentration and its gradient as well as the rule of narrower pollution range in deeper stratum. Moreover, COD is mainly transported and diffused in groundwater of sandy soil in the first and second layers. However, under accident condition II, the pollutant concentration begins to decay gradually after its transport and diffusion tends to be stable. Besides, in terms of dominance, dispersion is to transverse transport of pollutants what advection is to longitudinal transport. If considering random dispersion, the final results see higher peak concentration of COD and longer transverse distance from pollution center compared to transport route. What’s more, the pollution plume changes and concentration isocline becomes slightly irregular. 相似文献
107.
胶州湾海域COD浓度场数值计算应用研究 总被引:3,自引:0,他引:3
COD作为有机污染物,是影响近海海域水质的主要指标之一,本文采用分步杂交数值计算方法,在模拟计算了胶州湾海域M2分潮潮流场的基础上,根据胶州湾沿岸青岛市排污口的COD排放量,对胶州湾海域中的COD浓度分布作了数值计算对基未来的水质状况作了预测。 相似文献
108.
Dilek Erdirencelebi Izzet Ozturk Emine Ubay Cokgor Gulseren Ubay Tonuk 《洁净——土壤、空气、水》2007,35(2):178-182
Sulfate‐reduction data from various anaerobic reactor configurations, e. g., upflow anaerobic sludge blanket reactor (UASBR), completely stirred tank reactor (CSTR), and batch reactor (BR) with synthetic wastewaters, having glucose and acetate as the substrates and different levels of sulfate, were evaluated to determine the level of sulfate‐reducing activity by sulfate‐reducing bacteria coupled to organic matter removal. Anaerobic reactors were observed for the degree of competition between sulfate‐reducing sulfidogens and methane producing bacteria during the degradation of glucose and acetate. Low sulfate‐reducing activity was obtained with a maximum of 20% of organic matter degradation with glucose‐fed upflow anaerobic sludge bed reactors (UASBRs), while a minimum of 2% was observed with acetate‐fed batch reactors. The highest sulfate removal performance (72–89%) was obtained from glucose fed‐UASB reactors, with the best results observed with increasing COD/SO4 ratios. UASB reactors produced the highest level of sulfidogenic activity, with the highest sulfate removal and without a performance loss. Hence, this was shown to be the optimum reactor configuration. Dissolved sulfide produced as a result of sulfate reduction reached 325 mg/L and 390 mg/L in CST and UASB reactors, respectively, and these levels were tolerated. The sulfate removal rate was higher at lower COD/SO4 ratios, but the degree of sulfate removal improved with increasing COD/SO4 ratios. 相似文献
109.
化学需氧量(COD)、五日生化需氧量(BOD_5)及溶解性有机碳(DOC)是指示湖泊水质的重要指标,然而上述指标测定通常耗费大量时间、试剂及人力物力且排放大量有害废液.有色可溶性有机物(CDOM)是溶解性有机物(DOM)中可以强烈吸收光谱中的紫外光和可见光的部分,数据测定耗时短、方便快捷,且样品处理过程环境友好,能在很大程度上反映湖泊水质.本研究基于2016年2、5和8月在太湖均匀布设的32个采样点进行样品采集,运用光谱吸收与三维荧光-平行因子分析(EEMs-PARAFAC)探究太湖CDOM的光谱吸收和荧光组分,探讨CDOM光谱指标对湖泊BOD_5、COD及DOC浓度等湖泊环境质量指标的可替代性.结果表明:(1)运用EEMs-PARAFAC方法解析出3种荧光组分:类腐殖酸C1、类酪氨酸C2和类色氨酸C3.(2) COD和BOD_5和DOC在空间上呈现出相似的分布趋势,不同水期的最高值均出现在竺山湾和梅梁湾,由西北湖区至中部敞水区、东南湖湾递减.(3)在不同水期,COD、BOD_5、DOC浓度和C1组分均表现为丰水期极显著大于枯水期和平水期,a_(254)在丰、平、枯水期间无显著性差异,最大值出现在丰水期;C2与C3组分均在枯水期和平水期极显著大于丰水期.(4)在不同水文时期,COD、BOD_5和DOC浓度均与a_(254)、类腐殖酸C1呈显著正相关,丰水期太湖COD、BOD_5和DOC浓度与CDOM光谱指标的线性相关性要优于枯水期和平水期.(5) CDOM光谱指标在不同水文时期均能很好地替代COD、BOD_5和DOC等作为反映太湖水体中有机物污染程度及湖泊水质的指标. 相似文献
110.
In order to determine the interference caused by chloride ions in Chemical Oxygen Demand (COD) measurements, synthetically prepared samples with various COD and chloride concentrations were analyzed. In addition, statistical analyses of the results were performed to calculate the real COD caused by the presence of organic substances in chlorinated wastewaters. The results of regression analyses showed good correlation between chloride concentrations and COD levels. A mathematical model is proposed on the basis of the statistical analyses. To calculate the real COD value of a wastewater sample, firstly, the chloride and interfered (or apparent) COD concentrations should be measured and then interference due to the chloride is calculated using the model equation proposed in this study. The real COD value was found by subtracting the COD due to chloride from the apparent COD. The reliability of the proposed model was also validated on real domestic wastewater samples, which were mixed with real seawater in various volumetric ratios to generate a range of salinity concentrations. These real saline samples gave good estimates of real COD with the results indicating that the proposed model can be used with acceptable confidence. 相似文献