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排序方式: 共有892条查询结果,搜索用时 31 毫秒
81.
磷酸铵镁法综合处理磷酸盐工业废水和垃圾渗滤液研究 总被引:1,自引:0,他引:1
探讨了磷酸铵镁法综合处理磷酸盐工业废水和垃圾渗滤液的可行性.探讨了pH、物质摩尔配比、搅拌速度、反应时间、陈化时间等因素对氨氮和磷酸盐去除效果的影响.实验得出只加MgSO4·7H2O)处理氨氮质量浓度为2 677.34 mg/L的垃圾渗滤液和磷酸盐质量浓度为l 804.48 mg/L的磷酸盐工业废水时的较佳实验条件为:搅拌速度200 r/min左右,反应时间20 rain,pH=9.5,n(Mg):n(P):n(N)=1.5:1.187:1.0.在陈化时间为30 min以及上述实验条件下,磷酸盐的去除率为99.53%,处理液中的残磷质量浓度为6.79 mg/L,氨氮的去除率为87.56%,残氮质量浓度为76.12 mg/L.并对所得磷酸铵镁沉淀进行了X-衍射光谱和扫描电镜分析. 相似文献
82.
城市垃圾渗滤液对地下水的污染及防治对策 总被引:8,自引:0,他引:8
文中主要阐述了城市垃圾渗滤液对地下水的污染情况,分析了垃圾渗液的主要成分,提出了环境监测方法,并针对垃圾渗滤液的特征以及我国目前的情况提出了其污染防治对策。 相似文献
83.
利用赤泥制备复合混凝剂PAFCS(聚合硫酸氯化铝铁)并以炉渣作为吸附剂对垃圾渗滤液进行预处理,对SS和色度的去除率分别为84%和92%,对COD的去除率可达53.3%,还提高了渗滤液的可生化性。然后采用两段SBR法对垃圾渗滤液进行生化处理,结果显示:通过对降解COD和氨氮的两类微生物分别进行培养,保持了较高的生物活性,进而提高了对此类高浓度难降解废水的处理效率。通过两段SBR处理以后,COD、BOD和氨氮的去除率分别为88%、94%和89%,出水水质达到了国家《生活垃圾填埋污染控制标准》(GB 16889—1997)的二级标准。 相似文献
84.
垃圾渗滤液的磷酸铵镁沉淀法预处理技术研究 总被引:17,自引:0,他引:17
研究了磷酸铵镁沉淀法 (MAP)去除氨氮、COD以及难降解有机物的效果。试验结果表明 ,在投加药剂Mg∶N∶P摩尔比为 1∶1∶0 7,pH 9~ 9 5的条件下 ,垃圾渗滤液氨氮的去除率在 70 %左右 ,COD的去除率为 10 %~ 2 0 % ,而难降解有机物的去除率达到了 4 0 %~ 5 0 % (以UV2 6 0 表征 )。并且经MAP法处理后垃圾渗滤液的可生化性也得到了一定的改善 ,UV2 6 0 /COD值从 9 1× 10 - 4降低到 (6 1~ 6 5 )× 10 - 4。 相似文献
85.
针对垃圾渗滤液成分复杂而且种类较多、有机物浓度高、水质、水量变化大、NH3-N含量高、微生物营养元素比例失调等特点,介绍了渗滤液的预处理技术和深度处理—生物处理工艺,尤其详细分析了生物处理法的最佳处理条件、效率。 相似文献
86.
87.
本文对新沂市北马陵生活垃圾处理方面的设计方法进行了探讨。运用多种方式和设计理念来处理生活垃圾问题,可以改善城区面貌,提高居民的生活环境水平,能够为新沂市资源环境做出一定的贡献,具有明显的社会和环境效益。 相似文献
88.
89.
In this study, the adsorption of bisphenol A (BPA) and 17α-ethinyl estradiol (EE2) from landfill leachate onto single-walled carbon nanotubes (SWCNTs) was investigated. Different leachate solutions were prepared by altering the pH, ionic strength, and dissolved organic carbon (DOC) in the solutions to mimic the varying water conditions that occur in leachate during the various stages of waste decomposition. The youngest and oldest leachate solutions contained varying DOC and background chemistry and were represented by leachate Type A (pH = 5.0; DOC = 2500 mg/L; conductivity = 12,500 μS/cm; [Ca2+] = 1200 mg/L; [Mg2+] = 470 mg/L) and Type E (pH = 7.5; DOC = 250 mg/L; conductivity = 3250 μS/cm; [Ca2+] = 60 mg/L; [Mg2+] = 180 mg/L). These solutions were subsequently combined in different ratios to produce intermediate solutions, labeled B-D, to replicate time-dependent changes in leachate composition. Overall, a larger fraction of EE2 was removed as compared to BPA, consistent with its higher log KOW value. The total removal of BPA and EE2 decreased in older leachate solutions, with the adsorptive capacity of SWCNTs decreasing in the order of leachate Type A > Type B > Type C > Type D > Type E. An increase in the pH from 3.5 to 11 decreased the adsorption of BPA by 22% in young leachate and by 10% in old leachate. The changes in pH did not affect the adsorption of EE2 in the young leachate, but did reduce adsorption by 32% in the old leachate. Adjusting the ionic strength using Na+ did not significantly impact adsorption, while increasing the concentration of Ca2+ resulted in a 12% increase in the adsorption of BPA and a 19% increase in the adsorption of EE2. DOC was revealed to be the most influential parameter in this study. In the presence of hydrophilic DOC, represented by glucose in this study, adsorption of the endocrine disrupting compounds (EDCs) onto the SWCNTs was not affected. In the absence of SWCNTs, hydrophobic DOC (i.e., humic acid) adsorbed 15-20% of BPA and EE2. However, when the humic acid and SWCNTs were both present, the overall adsorptive capacity of the SWCNTs was reduced. Hydrophobic (π-π electron donor-acceptor) interactions between the EDCs and the constituents in the leachate, as well as interactions between the SWCNTs and the EDCs, are proposed as potential adsorption mechanisms for BPA and EE2 onto SWCNTs. 相似文献
90.
Varank G Demir A Top S Sekman E Akkaya E Yetilmezsoy K Bilgili MS 《The Science of the total environment》2011,409(17):3183-3196
Four identical pilot-scale landfill reactors with different alternative composite liners were simultaneously operated for a period of about 540 days to investigate and to simulate the migration behaviors of phenolic compounds (phenol, 2-CP, 2-MP, 3-MP, 4-MP, 2-NP, 4-NP, 2,4-DNP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP) and heavy metals (Pb, Cu, Zn, Cr, Cd, Ni) from landfill leachate to the groundwater. Alternative landfill liners of four reactors consist of R1: Compacted clay liner (10 cm + 10 cm, k = 10−8 m/sn), R2: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm + 10 cm, k = 10−8 m/sn), R3: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm, k = 10−8 m/sn) + bentonite liner (2 cm) + compacted clay liner (10 cm, k = 10−8 m/sn), and R4: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm, k = 10−8 m/sn) + zeolite liner (2 cm) + compacted clay liner (10 cm, k = 10−8 m/sn). Wastes representing Istanbul municipal solid wastes were disposed in the reactors. To represent bioreactor landfills, reactors were operated by leachate recirculation. To monitor and control anaerobic degradation in the reactors, variations of conventional parameters (pH, alkalinity, chloride, conductivity, COD, TOC, TKN, ammonia and alcaly metals) were also investigated in landfill leachate samples. The results of this study showed that about 35-50% of migration of organic contaminants (phenolic compounds) and 55-100% of migration of inorganic contaminants (heavy metals) to the model groundwater could be effectively reduced with the use of bentonite and zeolite materials in landfill liner systems. Although leachate contaminants can reach to the groundwater in trace concentrations, findings of this study concluded that the release of these compounds from landfill leachate to the groundwater may potentially be of an important environmental concern based on the experimental findings. 相似文献