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991.
包埋固定化微生物的特性研究 总被引:1,自引:0,他引:1
文章通过实验研究了PVA与海藻酸钠混合载体包埋固定化微生物系统降解有机物的过程,并对其特性进行了分析。结果发现运行初期凝胶体有凝胶溶出现象,第一天凝胶有机物溶出高达2 173 mg,随后溶出量减少,7~8天溶出停止;同时发现包埋后的微生物活性有损伤和恢复的过程,损伤时相对活性为0.27经过恢复可达到0.85;另外,凝胶的粒径和比重等物理特性也随时间变化,最后趋于稳定。一年多运行实验发现包埋凝胶体的抗持久性也较好。这些特性的探讨将为工程应用提供理论指导。 相似文献
992.
UASB处理高浓度精细化工综合废水的启动研究 总被引:1,自引:0,他引:1
通过实验室小试,研究了UASB反应器对于精细化工废水中高浓度、难降解有机污染物的去除。在水质监测的基础上,研究了UASB反应器启动过程中各指标变化规律;比较了不同的水力负荷与进水COD浓度对工艺运行的影响;比较了VFA与出水COD的相关性;培养出了成型的颗粒污泥。UASB反应器进水COD浓度达到3 500 mg/L时,容积负荷达到7.0 kgCOD/(m^3.d)。试验证明,采用“UASB+好氧”工艺可改善化工废水的可生化性,可有效去除高浓度化工废水中难降解的有机污染物。 相似文献
993.
交替式活性污泥法是近年来发展起来的一种新的污水处理工艺,它在一个反应器或一组反应器中通过时间或空间的交替实现对污水的处理。从最基本的形式到后来的各种变形,交替式活性污泥法工艺在控制系统、运行模式上都发展迅速。文章首先给出了交替式活性污泥法的特点,并在此基础上分别对三沟式氧化沟、UNITANK工艺、交替式内循环活性污泥工艺(AICS)和五箱一体化活性污泥工艺这几种典型的交替式活性污泥法进行了概述,最后提出了交替式活性污泥法的问题和其发展方向。交替式活性污泥法工艺是一种高效、经济、灵活的污水处理工艺,具有很好的应用前景。 相似文献
994.
Lijie LI Qunhui WANG Xuesong LI Shuo YANG 《Frontiers of Environmental Science & Engineering in China》2008,2(1):32-35
During brewery wastewater treatment by a hydrolyzation-food chain reactor (FCR) system, sludge was recycled to the anaerobic
segment. With the function of hydrolyzation acidification in the anaerobic segment and the processes of aerobic oxidation
and antagonism, predation, interaction and symbiosis among microbes in multilevel oxidation segment, residual sludge could
be reduced effectively. The 6-month dynamic experiments show that the average chemical oxygen demand (COD) removal ratio was
92.6% and average sludge production of the aerobic segment was 8.14%, with the COD of the influent at 960–1720 mg/L and hydraulic
retention time (HRT) of 12 h. Since the produced sludge could be recycled and hydrolyzed in the anaerobic segment, no excess
sludge was produced during the steady running for this system. 相似文献
995.
996.
概述了蚯蚓生态滤池的研究进展,介绍了蚯蚓生态滤池化学除磷的工艺流程和设备参数;由试验得出氯化铁(FeCl3·6H2O)是蚯蚓生态滤池化学除磷的合适药剂,并确定最经济投加量为50mg/L;在此条件下,研究了化学除磷小试滤池产生的污泥性质,包括污泥产率的变化、重金属含量、污泥的脱水性能、污泥的稳定化程度以及污泥的最终处置方法。 相似文献
997.
Nonylphenol in the environment: a critical review on occurrence, fate, toxicity and treatment in wastewaters 总被引:16,自引:0,他引:16
Soares A Guieysse B Jefferson B Cartmell E Lester JN 《Environment international》2008,34(7):1033-1049
Nonylphenol is a toxic xenobiotic compound classified as an endocrine disrupter capable of interfering with the hormonal system of numerous organisms. It originates principally from the degradation of nonylphenol ethoxylates which are widely used as industrial surfactants. Nonylphenol ethoxylates reach sewage treatment works in substantial quantities where they biodegrade into several by-products including nonylphenol. Due to its physical-chemical characteristics, such as low solubility and high hydrophobicity, nonylphenol accumulates in environmental compartments that are characterised by high organic content, typically sewage sludge and river sediments, where it persists. The occurrence of nonylphenol in the environment is clearly correlated with anthropogenic activities such as wastewater treatment, landfilling and sewage sludge recycling. Nonylphenol is found often in matrices such as sewage sludge, effluents from sewage treatment works, river water and sediments, soil and groundwater. The impacts of nonylphenol in the environment include feminization of aquatic organisms, decrease in male fertility and the survival of juveniles at concentrations as low as 8.2 mug/l. Due to the harmful effects of the degradation products of nonylphenol ethoxylates in the environment, the use and production of such compounds have been banned in EU countries and strictly monitored in many other countries such as Canada and Japan. Although it has been shown that the concentration of nonylphenol in the environment is decreasing, it is still found at concentrations of 4.1 mug/l in river waters and 1 mg/kg in sediments. Nonylphenol has been referred to in the list of priority substances in the Water Frame Directive and in the 3rd draft Working Document on Sludge of the EU. Consequently there is currently a concern within some industries about the possibility of future regulations that may impose the removal of trace contaminants from contaminated effluents. The significance of upgrading sewage treatment works with advanced treatment technologies for removal of trace contaminants is discussed. 相似文献
998.
《International Journal of Sustainable Engineering》2013,6(3):228-234
Disposal of sewage sludge from waste water treatment plants is a serious environmental problem of increasing magnitude. Waste water treatment generates as much as 70 g of dry solids per capita per day. Although one of the disposal solutions for this waste is through incineration, still almost 30% of sludge solids remain as ash. This paper presents results related to reuse of sewage sludge ash in concrete. The sludge was characterised for chemical composition (X-ray flourescence analysis), crystalline phases (X-ray diffraction analysis) and pozzolanic activity. The effects of incineration on crystal phases of the dry sludge were investigated. Two water/cement (W/C) ratios (0.55 and 0.45) and three sludge ash percentages (5%, 10% and 20%) per cement mass were used as filler. The mechanical performance of sewage sludge ash concrete (SSAC) at different curing ages (3, 7, 28 and 90 days) was assessed by means of mechanical tests and capillary water absorption. Results show that sewage sludge ash leads to a reduction in density and mechanical strength and to an increase in capillary water absorption. Results also show that SSAC with 20% of sewage sludge ash and W/C = 0.45 has a 28 day compressive strength of almost 30 MPa. SSAC with a sludge ash contents of 5% and 10% has the same capillary water absorption coefficient as the control concrete; as for the concrete mixtures with 20% sludge ash content, the capillary water absorption is higher but in line with C20/25 strength class concretes performance. 相似文献
999.
针对工业废水采用普通活性污泥法处理易出现的丝状菌型污泥膨胀,分析和总结出五种主要膨胀类型:低负荷型、低溶解氧型、营养缺乏型、高硫化物型、pH值不平衡型。对污泥负荷、溶解氧、污水种类、营养成分及pH值和温度的变化等因素对污泥膨胀中菌胶团和丝状菌生长的相互影响进行阐述,给出污泥膨胀理论,并对不同类型的污泥膨胀提出相应的控制方法。 相似文献
1000.
为进一步提高循环式活性污泥工艺(CASS)的脱氮除磷效果,改变其运行方式,采用好氧脉冲曝气,提出频繁硝化-反硝化循环式活性污泥工艺(FND-CASS).结果表明,FND-CASS工艺与CASS工艺相比,在去除污水中有机物方面能力略有下降,但在脱氮除磷方面具有明显的优势.在同样的进水流量且DO浓度控制较低的运行条件下,F... 相似文献