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Qing Yang Shuying Wang Anming Yang Jianhua Guo Fengyang Bo 《Frontiers of Environmental Science & Engineering》2007,1(1):33-38
Since eutrophication has become increasingly severe in China, nitrogen and phosphorous have been the concern of wastewater treatment, especially nitrogen removal. The stabilization of the intelligent control system and nitrogen removal efficiency were investigated in a pilot-scale aerobic-anoxic sequencing batch reactor (SBR) with a treatment capacity of 60 m3/d. Characteristic points on the profiles of dissolved oxygen (DO), pH, and oxidation reduction potential (ORP) could exactly reflect the process of nitrification and denitrification. Using the intelligent control system not only could save energy, but also could achieve advanced nitrogen removal. Applying the control strategy water quality of the effluent could stably meet the national first discharge standard during experiment of 10 months. Even at low temperature (t = 13°C), chemical oxygen demand (COD) and total nitrogen (TN) in the effluent were under 50 and 5 mg/L, respectively. 相似文献
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以pH和ORP作为脉冲SBR工艺的实时控制参数 总被引:9,自引:0,他引:9
为了实现脉冲SBR深度脱氮的实时控制,以某污水处理厂市政污水为处理对象,考察了脉冲SBR在深度脱氮过程中pH及ORP的变化规律。试验结果表明,pH及ORP的变化规律与脉冲SBR有机物去除、硝化与反硝化过程存在较好的相关关系。可以根据pH和ORP变化曲线上的特征点对脉冲SBR进行实时控制。并考察了污水C/N(COD/NH4^+-N)对pH及ORP的变化规律的影响。在硝化过程中,C/N对pH及ORP曲线变化点的出现没有影响;在反硝化过程中,应结合pH值“硝酸盐峰”和ORP“硝酸盐膝”来判断低C/N污水反硝化的终点。在该试验中,出水TN低于2mg/L,TN去除率可达到96%以上。 相似文献
116.
Bioaccumulation and physiological effects of excess lead in a roadside pioneer species Sonchus oleraceus L 总被引:2,自引:0,他引:2
Xiong ZT 《Environmental pollution (Barking, Essex : 1987)》1997,97(3):275-279
Seedlings of Sonchus oleraceus L. were transplanted to soil supplied with lead acetate at dosages of 0, 800, 1600 and 3200 mg kg(-1) DW. Measures of chlorophyll content, peroxidase (POD) activity, shoot length, biomass and Pb content in the plant tissues were obtained from the experimental plants. With increasing amounts of Pb in the soil, the chlorophyll content, shoot length and biomass decreased, while POD activity and Pb content in the plant tissues increased. At 3200 mg kg(-1) Pb treatment, Pb content in the plant leaf, stem and root were 65.67, 149.82 and 1113.24 mg kg(-1), respectively. Only at 3200 mg kg(-1) Pb treatment did chlorophyll content, shoot length and biomass significantly increase by 18, 15 and 44%, respectively, while POD decreased by 39% over the control. The potential of applying this species in phytoremediation of Pb contaminated roadside soils and thus restoration of the roadside vegetation are discussed. 相似文献
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以石煤渣为主要原料研制的工业窑炉保温材料,具有较高的耐压强度和较低的导热率。分析研究了保温材料在烧成工艺过程中的物理化学变化,同时通过试验确定了干燥和烧成过程的工艺参数,为石煤渣治理和综合利用开辟了一种新的途径。 相似文献
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Comparison of microbial community between two shallow freshwater lakes in middle Yangtze basin, East China 总被引:2,自引:0,他引:2
In order to investigate the role of the microbial community in aquatic ecology and nutrient transformations in the development of eutrophication in large shallow freshwater lakes along Yangtze River, the microbial community in the depth-related sediment in Lake Chaohu and Lake Longganhu were compared. Lake Chaohu is one of the three most polluted lakes in China. However, the neighboring Lake Longganhu, a mesotrophic lake, is relatively pristine. The total phosphorous (TP) and total nitrogen (TN) concentration in water was detected at 0.193 mgl(-1) and 3.035 mgl(-1) for Lake Chaohu, 0.051 mgl(-1) and 0.774 mgl(-1) for Lake Longganhu, respectively. The population of the microorganisms with various ecological nutrient transforming functions (e.g. phosphate solubilizing, denitrifying and cellulose decomposing) and a batch of environmental parameters concerning the nutrient accumulating and transforming (e.g. total organic carbon, total nitrogen, and total phosphorous concentrations) were assayed in the depth-related sediment samples from several defined points in both lakes. The sediment samples from Lake Chaohu showed higher density of actinomycetes (P<0.05) and phosphate-solubilizing bacteria (P<0.001) and less profusion of denitrifying bacteria (P<0.05) and cellulolytic microbes (P<0.001), compared with those of Lake Longganhu. The data suggested that the current microbial community in the sediment of Lake Chaohu is in favor of sustaining or further accelerating the process of the lake eutrophication. A possible positive feedback loop which consists of sustained growth of microorganisms and gradual decline of lake eutrophic status is worth further discussing. 相似文献
119.
Determination of polycyclic musks in sewage sludge from Guangdong, China using GC-EI-MS 总被引:12,自引:0,他引:12
Polycyclic musks [Cashmeran (DPMI), Celestolide (ADBI), Phantolide (AHMI), Traseolide (ATII), Tonalide (AHTN) and Galaxolide (HHCB)] were Soxhlet extracted, separated and analyzed in sewage sludge from six different wastewater treatment plants from Guangdong, China, using GC and GC-EI-MS. DPMI, ADBI, HHCB, AHTN were found in all samples, and ATII was not found in any sample. AHMI was detected in five out of six samples. HHCB and AHTN were the two major polycyclic musks found in highest concentrations in sludge. The sludge from municipal wastewater treatment plants contained HHCB, AHTN and DPMI at concentrations between 5.416 and 21.214, 0.715 and 6.195 and 0.599 and 2.870 mg/kg (dry), respectively. The highest concentration was found in sludge from one cosmetic plant at 703.681 mg HHCB/kg (dry). The results indicate that there are two sources of polycyclic musks: domestic sewage and industrial wastewater. 相似文献
120.