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101.
电解法处理利福霉素SV钠废渣分离液的研究 总被引:2,自引:0,他引:2
根据电化学原理,采用电解法,利用铁屑与炭粒作电极,处理利福霉素SV钠药渣分离液,讨论各种因素对分离液污染物作效果的影响,COD去除率可达91.8%左右,脱色率可达95%左右。 相似文献
102.
Renan Felicio dos Reis Joao Sergio Cordeiro Xavier Font Cali Laguna Achon 《Drying Technology》2020,38(10):1247-1260
AbstractSewage treatment can be classified into three phases: liquid, gaseous, and solid. Treatment of solids is performed in several steps, and the greatest difficulty in removing water from sewage sludge is due to the bound water present in the sludge. Thus, biodrying, a drying method that can be classified as biological, has been recently applied to treat this type of waste. This review paper aims to report and compile data from 49 biodrying assays of sewage sludge found in the literature (through the present, 2019) into one synthesis table, to discuss and compare the numerous variables found in these papers and their implications for biodrying, and to suggest possibilities for future research. This paper additionally intends to improve knowledge of biodrying and to consequently contribute to the monitoring and understanding of the process. 相似文献
103.
Effect of operating conditions in removal of arsenic from water by nanofiltration membrane 总被引:2,自引:0,他引:2
The removal of arsenic from synthetic waters and surface water by nanofiltration (NF) membrane was investigated. In synthetic solutions, arsenic rejection experiments included variation of arsenic retentate concentration, transmembrane pressure, crossflow velocity and temperature. Arsenic rejection increased with arsenic retentate concentration. Arsenic was removed 93-99% from synthetic feed waters containing between 100 and 382 μg/L as V, resulting in permeate arsenic concentrations of about 5 μg/L. Under studied conditions, arsenic rejection was independent of transmembrane pressure, crossflow velocity and temperature. In surface water, the mean rejection of As V was 95% while the rejection of sulfate was 97%. The co-occurrence of dissolved inorganics does not significantly influence arsenic rejection. The mean concentration of As in collected permeated was 8 μg/L. The mean rejection of TDS, total hardness and conductivity were 75, 88 and 75% respectively. 相似文献
104.
塑料旋转成型的特点与研究 总被引:3,自引:0,他引:3
介绍了塑料旋转成型的原理和主要特点,对旋转成型制品中易出现的气泡和弯曲,收缩现象,以及冲击强度低的原因进行了分析研究,相应地提出了减少或消除旋转成型制品中的气泡,减少或消除制品收缩和弯曲,以及提高制品冲击强度的主要途径。 相似文献
105.
在实验室,采用SBR生化反应器,分别研究了经空气吹脱预处理和未经预处理的新型气化炉煤气洗涤废水经驯化建立的生态系统脱除氨态氮和COD以及脱氮模式的区别,得出以下结论:新型气化炉煤气洗涤废水可采用短程亚硝化型硝化形式直接进行生化处理。 相似文献
106.
An interpenetration network (IPN) was synthesized from 2‐hydroxyethyl methacrylate (HEMA) and chitosan, p(HEMA/chitosan) via UV‐initiated photo‐polymerization. The selectivity to different heavy metal ions viz Cd(II), Pb(II), and Hg(II) to the IPN membrane has been investigated from aqueous solution using bare pHEMA membrane as a control system. Removal efficiency of metal ions from aqueous solution using the IPN membranes increased with increasing chitosan content and initial metal ions concentrations, and the equilibrium time was reached within 60 min. Adsorption of all the tested heavy metal ions on the IPN membranes was found to be pH dependent and maximum adsorption was obtained at pH 5.0. The maximum adsorption capacities of the IPN membrane for Cd(II), Pb(II), and Hg(II) were 0.063, 0.179, and 0.197 mmol/g membrane, respectively. The adsorption of the Cd(II), Hg(II), and Pb(II) metal ions on the bare pHEMA membrane was not significant. When the heavy metal ions were in competition, the amounts of adsorbed metal ions were found to be 0.035 mmol/g for Cd(II), 0.074 mmol/g for Hg(II), and 0.153 mmol/g for Pb(II), the IPN membrane is significantly selective for Pb(II) ions. The stability constants of IPN membrane–metal ions complexes were calculated by the method of Ruzic. The results obtained from the kinetics and isotherm studies showed that the experimental data for the removal of heavy metal ions were well described with the second‐order kinetic equations and the Langmuir isotherm model. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
107.
由于混凝土抗拉能力较差,双曲组合扭壳抵抗悬垂线方向的主拉应力控制至关重要.如果拆模顺序不当,可能会使壳体结构产生过大的拉应力.为解决此问题,以华工扭壳为例,对平行四边形底面双曲组合扭壳的满堂脚手架施工拆模顺序进行全面优化分析,并与工程实测进行对比,得出较为合理的拆模方式. 相似文献
108.
旋流-静态微泡浮选柱净化含油废水试验研究 总被引:1,自引:0,他引:1
为了提高含油废水处理效果、简化处理工艺,提出了以旋流一静态微泡浮选柱为核心的水处理工艺,在自行研制的试验装置系统上,研究了循环泵压力、柱体过流速度、混凝剂种类及投加量、表面活性剂投加量、油水pH值等主要工艺参数对模拟含油废水除油效果的影响.结果表明:以上因素均对脱油率有较大影响,在优化条件下,除油率可达95.7%,旋流-静态微泡浮选柱对含油废水有较高的净化能力. 相似文献
109.
李海军 《山东建筑工程学院学报》2009,(2)
2008年初南方地区抗击雪灾中大量使用融雪剂清除冰雪,进而引发对融雪剂所带来危害的关注,呼吁有关部门高度重视融雪剂对钢筋混凝土路面的腐蚀危害,提出合理除雪和科学使用融雪剂的方法。 相似文献
110.
介绍了运用控制爆破技术,对悬臂钢筋混凝土斜拉桥爆破拆除方法,指出了布孔、装药、防护等方面的技术问题. 相似文献