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261.
废水的生物脱氮除磷新工艺的设想 总被引:9,自引:0,他引:9
结合废水生物脱氮除磷机理和影响因素,在对几种典型脱氮除磷工艺氮、磷去除率进行比较的基础上,解析了一些典型工艺除氮除磷不足之处。根据重庆城市污水水质实际情况和地形的特点,设想一种新的生物脱 氮除磷工艺,从而弥补传统工艺的不足。可望提高系统的脱氮和除磷效率,达到更好的脱氮除磷的目的,减少对水体的污染。 相似文献
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263.
186菌生物流化床处理甲醇废水 总被引:7,自引:0,他引:7
用三相生物流化床工艺处理甲醇废水COD_(cr)容积负荷达4.24~12.32kg/m~3·d,去除率达82.7%~93.1%;甲醇容积负荷达1.8~3.9kg/m~3·d,去除率达81.4%~98.1%。加186菌种后,甲醇的容积负荷可提高到3.02~3.36kg/m~3·d,COD_(cr)去除率可达到89.3~96.7%。 相似文献
264.
煤渣填料固定化菌膜处理餐厅污水 总被引:3,自引:0,他引:3
以煤渣为填料,采用人工筛选优势菌挂膜固定化技术和直流式供水送风形式,对酒家、宾馆的餐厅污水进行生物接触氧化处理,COD和BOD的去除率可>90%,处理后排放水质可稳定达到COD≤100mg·1~(-1),BOD≤30mg·1~(-1),SS≤30mg·1~(-1),NH_3—N≤15mg·1~(-1)。推广应用结果表明,具有显著的经济效益和环境效益。 相似文献
265.
Preparation and characterization of visible-light-active nitrogen-doped TiO2 photocatalyst 总被引:4,自引:0,他引:4
A visible-light photocatalyst was prepared by calcination of the hydrolysis product of Ti(SO4)2 with ammonia as precipitator. The color of this photocatalyst was vivid yellow. It could absorb light under 550 nm wavelength. The crystal structure of anatase was characterized by XRD. The structure analysis result of X-ray fluorescence(XRF) shows that doped-nitrogen was presented in the sample. The photocatalytic activities were evaluated using methyl orange and phenol as model pollutants. The photocatalytic activities of samples were increasing gradually with calcination temperature from 400℃ to 700℃ under UV irradiation. It can be seen that the degradation of methyl orange follows zero-order kinetics. However, the calcination temperatures have no significant influence on the degradation of phenol under sunlight. The N-doped catalyst shows higher activity than the bare one under solar irradiation. 相似文献
266.
267.
Pencycuron application to soils: degradation and effect on microbiological parameters 总被引:2,自引:0,他引:2
Clay loam soil from agricultural fields of alluvial (AL) soil (typic udifluvent) and coastal saline (CS) soil (typic endoaquept) were investigated for the degradation and effect of pencycuron application at field rate (FR), 2-times FR (2FR) and 10-times FR (10FR) with and without decomposed cow manure (DCM) on soil microbial variables under laboratory conditions. Pencycuron degraded faster in CS soil and in soil amended with DCM. Pencycuron spiking at FR and 2FR resulted in a short-lived (in case of 10FR slightly longer) and transitory toxic effect on soil microbial biomass-C (MBC), ergosterol content and fluorescein diacetate hydrolyzing activity (FDHA). Amendment of DCM did not seem to have any counteractive effect of the toxicity of pencycuron on the microbial variables. The ecophysiological status of the soil microbial communities as expressed by microbial metabolic quotient (qCO2) and microbial respiration quotient (Q(R)) changed, but for a short period, indicating pencycuron induced disturbance. The duration of this disturbance was slightly longer at 10FR. Pencycuron was more toxic to the metabolically activated soil microbial populations, specifically the fungi. It is concluded that side effects of pencycuron at 10FR on the microbial variables studied were only short-lived and probably of little ecological significance. 相似文献
268.
We designed a microcosm experiment to assess the influence of inoculation with Eisenia foetida earthworms and the establishment of an Avena sativa cover crop on biological (enzyme activities and labile carbon fractions) soil quality indicators in a soil treated with a composted organic residue, and to determine the contribution of these treatments to carbon dioxide emissions from the soil to the atmosphere of the microcosm. The microcosms were incubated for 53 days under 28 °C/18 °C day/night temperatures. The addition of earthworms and the planting of A. sativa increased dehydrogenase activity of compost amended soil by about 44% after 23 days of incubation. The metabolic potential, calculated as the ratio dehydrogenase activity/water soluble C, was higher in the compost amended soil planted with A. sativa. The highest total amount of CO2–C evolved occurred in the soil treated with composted residue and earthworms (about 40% of the total amount of CO2 evolved came from earthworm activity). The planting of A. sativa increased the decomposition rate constant of organic matter in the amended soil but decreased the potentially mineralizable C pool. In conclusion, the establishment of an A. sativa cover crop and the addition of E. foetida to a degraded agricultural soil treated with composted residue were effective treatments for improving the biological and biochemical quality and the metabolic potential of the soil. 相似文献
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270.
应用错流式动态膜-生物反应器(CDMBR)对己内酰胺废水进行了180 d的实验,实验过程中测定反应器的膜出水和上清液的水质,并对污泥进行了耗氧呼吸速率测定.结果表明,上清液COD一直保持在100mg/L以下,而膜出水的则保持在50 mg/L以下,膜对上清液的COD去除率达50%,而对氮的去除没有贡献.可溶性细胞产物(SMP)在反应器内容易积累,停留足够的时间后能被生物降解.通过投加抑制剂测定耗氧呼吸速率,发现异养菌、硝化细菌和亚硝化细菌的活性由于F/M的降低和SMP积累受到一定的抑制,但不影响系统的处理效率.跨膜压力、膜面流速越大,通量衰减得也就越快. 相似文献