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311.
Matthew Pocernich David W. Litke 《Journal of the American Water Resources Association》1997,33(1):205-214
ABSTRACT: Accurate data about nutrient concentrations in wastewater treatment plant effluents are needed for river basin water-quality studies. As part of the U.S. Geological Survey's National Water-Quality Assessment Program in the South Platte River Basin, nutrient data were requested from 31 wastewater-treatment plants located in the basin. This article describes the types of nutrient data available from the plants, examines the variability of effluent nutrient concentrations, and discusses methods for estimation of nutrient concentrations where data are lacking. Ammonia was monitored at 88 percent of the plants, nitrite plus nitrate was monitored at 40 percent of the plants, and organic nitrogen and phosphorus were monitored at less than 25 percent of the plants. Median total nitrogen concentrations and median total phosphorus concentrations were small compared to typical literature estimates for wastewater-treatment plants with secondary treatment. Nutrient concentrations in effluent from wastewater-treatment plants varied widely between and within plants. For example, ammonia concentrations varied as much as 5 mg/L during a day, as much as 10 mg/L from day to day, and as much as 30 mg/L from summer to winter within a plant. In the South Platte River Basin, estimates of median annual ammonia and nitrite plus nitrate concentrations can be improved based on plant processes; and nitrite plus nitrate and organic nitrogen concentrations can be estimated based on ammonia concentrations. However, to avoid large estimation errors, more complete nutrient data from wastewater-treatment plants are needed for integration into river basin water quality studies. The paucity of data hinders attempts to evaluate the relative importance of point source and nonpoint source nutrient loadings to rivers. 相似文献
312.
Christopher I. Thornton Steven R. Abt Warren P. Clary 《Journal of the American Water Resources Association》1997,33(6):1279-1288
ABSTRACT: A meandering stream channel was simulated in the Hydraulics Laboratory at Colorado State University and a series of tests was conducted using four types of vegetation to evaluate the potential effects of vegetation on sediment deposition and retention in a stream channel. The data collected included average flow velocity, flow depth, length of vegetation, density of vegetation, cross-sectional area of the vegetative stem, wetted perimeter of the vegetative stem, and injection and flushing time. The findings indicated that the vegetation could retain from 30 to 70 percent of the deposited sediments. The ability of vegetation to entrap and retain sediment is related to the length and cross-sectional area of the vegetation. The variables describing the flow and the vegetative properties were combined to form a predictive parameter, the sedimentation factor (Sd) that can be compared with the amount of sediment entrapped by vegetation in a stream system. A relation was developed correlating vegetation length to sediment retention after flushing for flexibility and rigid vegetation. 相似文献
313.
314.
废水中甲酸萃取回收的研究 总被引:9,自引:1,他引:9
以ZYM混合溶剂为萃取剂,以含4.5%的甲酸的废水进行萃取试验,结果表明,ZYM具有良好的热稳定性和再生性,对废水中的甲酸有较高的萃取率。采用本萃取技术,不但具有显著的环境效益,而且还可回收甲酸,获得较好的经济效益。 相似文献
315.
316.
对抚顺石化公司化工塑料厂苯乙烯废水活性炭吸附装置的预处理设施、活性炭吸附及再生性能进行了评价,分析了出水水质超标的主要原因,用混凝沉淀-砂滤流程改进了原处理工艺,使出水水质得到了显著改善。 相似文献
317.
对焦化厂蒸氨废水中的有机物进行了GC/MS分析,发现酚类,吲哚,喹啉和硫醇是主要污染物成分。对旨在降低蒸氨废水硫化物含量的各种处理方法进行了比较。采用CWZ-01吸附剂的吸附法能使废水中硫化物降至30mg/L以下。 相似文献
318.
钻井污水是一种棕黑色的多组分复杂体系,含有大量粘土粒子、电解质、少量浮油和油田处理剂,基本上属于胶体体系。ξ电势是胶体的一个重要性质,试验中研究测试了几种常用无机絮凝剂处理钻井污水时ξ电势的变化,根据ξ电势的大小及等电点时絮凝剂的用量对其进行了筛选。 相似文献
319.
320.
太阳能光催化降解法去除水中罗丹明染料的研究 总被引:16,自引:0,他引:16
在太阳光的紫外线辐射下,应用载有TiO2薄层的平板式光催化反应器,进行了光催化降解法去除水中罗丹明染料的试验,结果表明,当紫外线辐射强度平均为33W/m^2,反应时间为18min时,水中罗丹明染料浓度由10mg/L降至0.01mg/L,在室国家排放标准,探讨了太阳能光催化反应系统的改进方向及工业化应用的有关问题。 相似文献