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271.
Experimental design of Fenton and photo-Fenton reactions for the treatment of cellulose bleaching effluents 总被引:1,自引:0,他引:1
Multivariate experimental design was applied to the treatment of a cellulose conventional bleaching effluent in order to evaluate the use of the Fenton reagent under solar light irradiation. The effluent was characterised by the general parameters total organic carbon (TOC), chemical oxygen demand and color, and it was analysed for chlorinated low molecular weight compounds using GC–MS. The main parameters that govern the complex reactive system: Fe(II) and H2O2 initial concentration, and temperature were simultaneously studied. Factorial experimental design allowed to assign the weight of each variable in the TOC removal after 15 min of reaction. Temperature had an important effect in the organic matter degradation, especially when the ratio of Fenton reagents was not properly chosen. Fenton reagent under solar irradiation proved to be highly effective for these types of wastewaters. A 90% TOC reduction was achieved in only 15 min of treatment. In addition, the GC–MS analysis showed the elimination of the chlorinated organic compounds initially detected in the studied bleaching effluents. 相似文献
272.
厌氧酸化—好氧法处理高浓度洗毛废水尾浆试验研究 总被引:2,自引:0,他引:2
采用厌氧酸化-好氧工艺对高浓度洗毛废水尾浆进行处理。试验结果表明,对于COD为25000mg/L的原废水,经1d的厌氧酸化和1d的二段串联的间歇活性污泥法好氧曝气处理,COD和BOD5的总去除率分别达到92%和99%以上,生化处理出水COD为1500~2000mg/L,BOD5<60mg/L。 相似文献
273.
ANAMMOX流化床反应器性能的研究 总被引:39,自引:9,他引:39
直接以氨为电子供体的反硝化反应是一种新的生物反应,可实现对两种氮素污染物的同时去除.探索了用流化床反应器开发这一反应,以处理厌氧消化污泥压滤液的可行性.试验发现,用该技术处理,无需供氧,也无需中和,并可有效地避免基质的抑制作用;平均氨和亚硝酸容积负荷率为42883和46491mg/(L·d),平均氨和亚硝酸去除率为8849%和9904%;由于ANAMMOX混培物产率较低,需要较长的SRT(>100d),有必要进一步研究ANAMMOX混培物的生长条件,以保证ANAMMOX反应器长期稳定运行. 相似文献
274.
本研究采用二氯甲烷分步萃取,硅胶柱净化和预分离、高效液相色谱结合薄层色谱的定性方法,从不同时期采集的城市污水处理厂二级出水中分离鉴定出七种染料,并对鉴定出的染料进行了定量分析。 相似文献
275.
There are numerous studies comparing different kinds of environmental taxes and standards. However, forms of environmental standards focused by former researchers are usually quantity-based limits/standards (e.g. pounds per day or pounds per unit of output). Concentration-based emission standard (e.g. milligrams per liter of wastewater) as one important form of environmental standard has not been given much attention. In this article, comparable estimates of their probable effect on enterprise pollution reduction will be developed for concentration-based effluent standards, effluent taxes, and a combination of both. A linear simulation model is used to clearly and obviously compare the effects of effluent taxes and concentration-based standards within the same figure. With one detailed application to the paper industry, some enlightenment and conclusions – as well as the general applicability of these principles – are then provided: Under the same effluent tax rate, enterprises, groups, and industries that are cleaner will reduce more pollutants than those that have higher pollutant abatement costs. It is recommended that effluent taxes are set by avoiding cutting it even at one stroke and considering the feasibility of pollution-reducing technology in various industries. It is necessary to reduce MAC of enterprises to better stimulate enterprises’ or industries’ emission reduction by preferential measures, such as high tax rate coordinated by speeding up the depreciation of environmental protection equipment. 相似文献
276.
电工电子产品陷入火灾后所产生的腐蚀性燃烧产物,可能会对电路和电工电子元器件的性能造成不同程度的损坏,使设备出现故障。测量和评估燃烧产物的腐蚀损坏效应对于保证与安全有关的电工电子设备正常运行是十分必要的。 相似文献
277.
278.
279.
ABSTRACT: A scaled hydraulic model was used as a schematic representation of the Peach Bottom Atomic Power Station (PBAPS) discharge into Conowingo Pond during critically low river flows. The model approximated flow and temperature patterns and the degree of recirculation are assessed. Under normal operation the effluent is carried downstream and dissipated within about two miles. However, during dry weather years, river inflows can decrease substantially, resulting in unknown recirculation of effluent and flow patterns in Conowingo Pond. This study was conducted to investigate and predict flow patterns in Conowingo Pond under critically dry weather conditions. A threshold river flow is also identified that indicates a measure of the river's ability to maintain downstream advection of the effluent. The study suggests a number of unexpected current patterns, potential recirculation of the effluent, and changes in the dilution of the effluent. 相似文献
280.
投加外碳源是污水厂尾水深度脱氮的重要手段.为充分对比多种碳源在极限脱氮条件下的性能及经济性,以及碳源对微生物种群结构的影响,选取甲醇、乙醇、葡萄糖和乙酸钠这4种单碳源,并采用反应速率较高的乙酸钠和乙醇与价格便宜的葡萄糖配制成4种复合碳源进行研究.结果表明,所有系统均能满足出水ρ(NOx--N)≤1.0mg·L-1的要求.单碳源系统,乙醇反应速率最快,投加量最省,费用最低.复合碳源系统,乙酸钠/葡萄糖(1:1)在COD/ρ(N)为6时,与乙酸钠/葡萄糖(1:3)、乙醇/葡萄糖(1:1)和乙醇/葡萄糖(1:3)在COD/ρ(N)为9、10和10时的效果相当,且乙酸钠/葡萄糖(1:1)系统反应速率最快且经济性最好.Illumina MiSeq高通量测序显示,经70 d左右的运行,微生物群落结构发生根本性变化.在与葡萄糖相关的系统,常规脱氮系统不常见的菌门Candidatus Saccharibacteria,丰度从种泥的1.16%提高到47.37%;相应地,在属水平Saccharibacteria_genera_incertae_sedis成为绝对优势菌种.研究结果可为污水厂尾水极限脱氮的碳源选择提供更全面的对比,也为碳源在微生物菌群驯化方面的作用提供更多参考和借鉴. 相似文献