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971.
HITNP同步除磷脱氮新工艺 总被引:5,自引:0,他引:5
HITNP同步除磷脱氮新工艺采用复合式活性污泥生物膜系统,避免了硝化菌和聚磷菌的污泥龄矛盾.利用反硝化除磷的“一碳两用”缓解原水碳源不足的矛盾.通过独特的硝化液回流方式,使全部污泥经历了释磷和聚磷循环,厌氧池污泥浓度是缺氧池污泥浓度的1.5~2倍,对进水中的大分子有机物降解效果好,厌氧池COD的去除率高,强化系统的除磷能力.以低碳氮比的生活污水为处理对象,长期的运行结果表明,该工艺出水中的总磷、氨氮、总氮和COD的去除率分别为91.1% 、88.7%、58.1%和88.6%.出水水质平均值为磷0.27 mg/L,氨氮1.74 mg/L,总氮17.30 mg/L和COD 24.38 mg/L.HITNP同步除磷脱氮新工艺具有稳定的同步除磷脱氮效果,出水达到国家城市污水厂污染物排放标准GB18918-2002一级B标准要求. 相似文献
972.
钴磷合金催化剂的制备及其催化分解磷化氢的研究 总被引:1,自引:0,他引:1
采用诱导化学沉积法制备系列Co-P合金,并将其引入PH3的分解试验.结果表明,所有样品均具有在较低温度下催化分解PH3的性能,且测定的表观催化反应温度随合金中磷质量分数的升高而降低,当磷的质量分数≥7.7%时,表观催化反应温度<450 ℃.选取Co86.3P13.7样品进行催化分解PH3气体的研究表明,实验条件下,PH3分解率随催化反应温度的升高呈现先增后减的趋势,但随总通气流量QPH3 QN2或通气量比QN2∶QPH3的增大而降低.控制催化反应温度为470 ℃、PH3进气流量QPH3=4~6 mL/min、通气比QN2∶QPH3=33~35时,催化剂可发挥最佳的催化性能,此时PH3的分解率达95%以上.对Co86.3P13.7不同处理温度下的X射线衍射(XRD)表征分析表明,样品在催化反应温度下发生晶化,有磷化物Co2P析出,但催化反应测试温度范围内晶化后的催化剂基本保持稳定. 相似文献
973.
R. Peter Richards 《Journal of the American Water Resources Association》1989,25(4):891-904
ABSTRACT: Evaluation of the non-point source pollutant load entering a lake from multiple tributaries requires either that all tributaries be monitored or that some extrapolation method be used to estimate loads originating in areas not monitored. Unmonitored areas include not only watersheds of tributaries that are not monitored, but also portions of a monitored tributary's drainage basin downstream from the monitoring site and areas of direct drainage. Significant portions of large lake drainage basins are often not monitored, and loads for these areas are often estimated by extrapolation. Six simple extrapolation procedures were evaluated by using them to estimate loads for areas that had been monitored and comparing the estimated loads with the monitored loads. Three approaches were based on inter-basin ratios of area, C-factor, and discharge. The other approaches used regression relationships between concentration and flow to estimate concentrations for the unmonitored basin. The ratio approaches generally were more reliable than the regression approaches. However, extrapolation by any method tested was not very precise. Some methods also were biased when applied to watersheds of a size different than the monitored one. Extrapolation by any of these methods would compromise the precision of the lake-wide load estimate, if the unmonitored area were a significant part of the entire basin. 相似文献
974.
Claire L. Schelske 《Journal of the American Water Resources Association》1989,25(6):1119-1130
ABSTRACT: Lake Okeechobee, the third largest lake in the United States, is a shallow, mixing basin with annual total phosphorus concentrations ranging from 50–100 μg P/L. Data, mainly from unpublished agency reports, are analyzed to determine if nutrients limit phytoplankton, to describe spatial and temporal variability in trophic state parameters, and to evaluate conclusions obtained from empirical trophic state models. Algal bioassay experiments that have been used to assess nutrient limitation have produced equivocal results. However, seasonal minima in orthophosphorus and inorganic nitrogen indicate that both nutrients may be limiting seasonally. Strong, but reverse north-south gradients and large seasonal changes in phosphorus and nitrogen concentrations, show that empirical models based on annual phosphorus loadings or concentrations are not adequate to predict chlorophyll concentrations or other trophic state variables. Spatially-segmented, multi-class phytoplankton-nutrient models of seasonal phytoplankton responses that are coupled with hydrodynamic models may provide predictability in assessing effects of changing nutrient loads on phytoplankton composition and standing crop. Successful modeling efforts of responses to nutrients also must deal with resuspended and benthic algae, periphyton, and emergent and submergent aquatic plants that must play important trophic roles in some of the lake basin. 相似文献
975.
环境行政执法难的理性分析与实践对策 总被引:1,自引:0,他引:1
环境行政执法难是非常态法律现象。从哲学的高度对环境行政执法难进行理性分析,环境行政执法难是多因素群共创的结果。对环境行政执法难的内外因进行解构,分清主次,着重解决影响环境执法难的主因,并适当关注影响环境执法难的助因,同时基于应然立场提出解决问题的实践进路。 相似文献
976.
977.
浮床栽培茭白的生物学特征及水质净化作用研究 总被引:2,自引:0,他引:2
通过水面浮床栽培实验研究了水培茭白(Zizania caduciflora)植株的生长,并与土栽茭白作了对比.结果表明,水培茭株高在201~250cm之间,根长在29~54cm之间,地上部分鲜重42~184.5g/单株,约占总重的70%~80%,水、土栽培茭白生物学特征无显著差异.水培茭白体内N含量较土栽茭白的高, N/P差别明显,P含量差别不大.水培茭白与其他水培植物相比具有较强的N、P吸收能力,直接吸收N、P量分别为240.20 kg/hm2·a和21.60 kg/hm2·a,是一种可用于富营养化水体水质净化的优良植物. 相似文献
978.
浅谈600 MW机组湿法脱硫吸收塔的设计 总被引:4,自引:0,他引:4
结合广东某600 MW机组吸收塔的设计实例,对吸收塔的结构尺寸、内部件及防腐等关键工艺设计进行了阐述,以便为国内同类型脱硫工程吸收塔的设计提供借鉴及参考. 相似文献
979.
J. Bai K. R. Li D. Y. Liu J. Zhang H. F. Zhang G. S. Liu J. L. Li Z. Y. Li D. M. Gao 《Water, Air, & Soil Pollution: Focus》2007,7(6):673-681
The distribution patterns and factors affecting uptake rates and turnover times of dissolved inorganic nutrients by heterotrophic
bacterioplankton (HB) in Jiaozhou Bay were studied based on in situ surveys and laboratory culturing. The uptake rates of
dissolved inorganic phosphorus (DIP) and dissolved inorganic nitrogen (DIN) by HB are limited by the temperature of the water
and the concentration of dissolved organic carbon. The turnover times of DIP and DIN by HB are regulated by the concentrations
of the nutrients and the numbers of HB, which show significant spatiotemporal variability in Jiaozhou Bay. HB may aggravate
the P-limitation of phytoplankton by competing for phosphorus in summer in Jiaozhou Bay. HB play an important role in the
biogeochemical cycling of nutrients and may increase the N:P ratio and the accumulation of DIN, thereby accelerating the imbalance
of the N:P ratio in Jiaozhou Bay. 相似文献
980.