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631.
采用图像处理技术,分析污水处理过程中投药量与絮凝图像的等效直径、分形维数和浓度特征参数之间的关系。考虑到投药自动控制的实际运行环境和实时性要求,采用Retinex算法解决光照不均现象,在图像处理主要环节上均采用小计算量算法。分析结果表明:在实际的自动控制中具有较好的实用性。 相似文献
632.
采用催化氧化—絮凝—沉淀工艺深度处理麦秸制浆造纸废水,处理规模为200 m3/d.在进水COD为150 ~ 263 mg/L、色度为64~128倍、SS为50~ 88 mg/L的水质情况下,处理后出水水质稳定,COD为38~ 52mg/L,色度为2~8倍,SS为12~23 mg/L,出水水质达到GB3544-2008《制浆造纸工业水污染物排放标准》的要求.采用该工艺深度处理麦秸制浆造纸废水的费用不超过0.55元/m3. 相似文献
633.
絮凝- 电气浮法处理乳化油废水 总被引:2,自引:0,他引:2
含乳化油废水由于表面活性剂的存在处理难度较大。通过絮凝——电气浮方法处理乳化油废水,确定絮凝及絮凝——电气浮所需的最佳絮凝剂用量;通过正交试验考察了pH值、电流密度、电极间距及气浮时间等操作参数的影响,得到絮凝一电气浮的最优操作条件为电流密度为20.83A/m^2,电极间距为1cm,pH值为7.4。在聚合硫酸铁投加量为50mg/L,电气浮30min时COD去除率可达95.2%。此方法对轴承厂废水的COD去除率可达75%,出水COD可降至91.9mg/L。结果表明用这种方法处理乳化油废水是可行的。 相似文献
634.
生物絮凝剂(普鲁兰)处理渗滤液的试验研究 总被引:2,自引:1,他引:1
通过试验对生物絮凝剂(普鲁兰)和其它絮凝剂处理渗滤液的效果进行了比较、分析,对絮凝机理进行了探讨。对普鲁兰与硫酸铝复合处理渗滤液进行了试验研究,试验表明:普鲁兰与硫酸铝复合在处理渗滤液方面有着较好的应用前景。其COD去除率80%,浊度去除率95%以上。 相似文献
635.
636.
In China, over 1.43×107 tons of dewatered sewage sludge, with 80% water content, were generated from wastewater treatment plants in 2007. About 60% of the COD removed during the wastewater treatment process becomes concentrated as sludge. Traditional disposal methods used by municipal solid waste treatment facilities, such as landfills, composting, or incineration, are unsuitable for sludge disposal because of its high water content. Disposal of sludge has therefore become a major focus of current environmental protection policies. The present status of sludge treatment and disposal methodology is introduced in this paper. Decreasing the energy consumption of sludge dewatering from 80% to 50% has been a key issue for safe and economic sludge disposal. In an analysis of sludge water distribution, thermal drying and hydrothermal conditioning processes are compared. Although thermal drying could result in an almost dry sludge, the energy consumption needed for this process is extremely high. In comparison, hydrothermal technology could achieve dewatered sewage sludge with a 50%–60% water content, which is suitable for composting, incineration, or landfill. The energy consumption of hydrothermal technology is lower than that required for thermal drying. 相似文献
637.
一种新型高效复合絮凝剂的研制 总被引:2,自引:0,他引:2
以本地产红黄土壤,经焙烧活化后,再用工业废酸浸渍,取出浸出液,在一定的条件下,加入适量活性硅酸,制备成聚硅酸氯化铝铁,其最佳活化工艺条件为烧焙温度700℃,焙烧时间2小时。 相似文献
638.
A New Approach for the Flocculation Mechanism of Chitosan 总被引:2,自引:0,他引:2
A peak III/I ratio (peak) in pyrene-fluorescence spectrum was used to measure the polarity of microenvironment of chitosan adsorbing pyrene molecules. The authors detected the pyrene-fluorescence spectrum of chitosan with different degrees of deacetylation (DD) and determined the relationship between the flocculation of bentonite colloid and the peak of chitosan with a different molecular weight (MW) and DD. It can be concluded that MW rather than DD plays a key role in the flocculation and that bond bridging rather than charge neutralization dominates the flocculation with chitosan from a microenvironmental structure of view. 相似文献
639.
Honey bees, Apis mellifera L., bred for hygienic behavior uncap and remove diseased and mite-infested brood. We hypothesized that within a colony bred for hygienic behavior, there would be differences in olfactory sensitivity among bees of the same age. We predicted that bees that initiate the behavior by perforating and uncapping brood would have greater olfactory sensitivity to the odor of the diseased brood, and would be better able to discriminate between odors of healthy and diseased brood, compared to bees that complete the behavior by removing the uncapped brood from the cells. Electroantennogram recordings of 15- to 21-day-old bees from three colonies demonstrated that bees collected while uncapping dead brood had significantly greater olfactory sensitivity to all concentrations of diseased brood odor compared to bees collected while removing brood. Proboscis-extension reflex discrimination conditioning demonstrated that 15- to 21-day-old bees collected while uncapping discriminated significantly better and generalized significantly less between the odors of diseased and healthy brood compared to bees collected while removing, when the odor of diseased brood was rewarded, but not when the odor of healthy brood was rewarded. Bees collected while uncapping brood that had been pierced with a pin had significantly less olfactory sensitivity than bees collected while uncapping freeze-killed brood, most likely because the pierced brood had greater stimulus intensity. Initiation of hygienic behavior depends on the olfactory sensitivity of the bee and stimulus intensity of the abnormal brood. Differential olfactory sensitivity and responsiveness among hygienic bees could lead to the apparent partitioning of the behavior into uncapping and removing components.Communicated by R.F.A. Moritz 相似文献
640.