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184.
采用文献调研法比较评价了膜生物反应器与传统生物工艺对垃圾渗滤液的处理效果。结果表明,渗滤液的水质特征(主要指COD)主要由渗滤液年龄决定,B/C值和渗滤液年龄对COD去除有重要影响。传统生物处理常采用多级组合工艺,渗滤液特性、工艺单元数、水力停留时间和有机负荷率等是影响COD去除的重要参数。近年来,MBR工艺的应用日益广泛,对于B/C值较低的老龄渗滤液,MBR工艺可获得更好的COD去除效果,也有利于废水的膜深度处理。 相似文献
185.
试验考察了东阿县污水处理厂一期A2/O工艺厌氧池去除有机污染物效能,当进水ρ(COD)为548.3 mg/L时,厌氧池平均去除率达78.7%。同时探讨了几种常见数学模型模拟厌氧池去除有机物规律情况,根据实际工程监测数据确定有机底物降解动力学常数,得出Grau模型、Stover-kincannon模型和改进的Monod模型较适合模拟厌氧池去除有机物的规律,并对模型进行了检验。 相似文献
186.
酸化液对厌氧释磷好氧吸磷速率的影响研究 总被引:3,自引:1,他引:2
采用序批式试验研究了酸化液对聚磷菌厌氧释磷好氧吸磷速率的影响。同一活性污泥混合液中聚磷菌的释磷潜力相当,混合液中挥发性脂肪酸越多则越有利于激发聚磷菌的释磷潜能。酸化液投加量越大,对应的混合液中聚磷菌的平均释磷速率也越大。当酸化液投加量为30 mg/L(以TOC计)时,聚磷菌的平均释磷速率达0.137 mg/(mg.d),是未投加酸化液工况的3.26倍。聚磷菌厌氧释磷过程中,活性污泥的MLVSS值逐渐增大,而MLSS值却不断减小,这是由聚磷菌释磷反应过程中聚磷颗粒和糖原的消耗,以及PHB的生成而产生的。碳源充足与否,对聚磷菌的平均好氧吸磷速率影响不大,研究各工况中,聚磷菌的平均吸磷速率在0.129~0.160 mg/(mg.d)内。碳源越充足,则聚磷菌在好氧吸磷反应持续的时间越长,因此,具有更强的超量吸磷能力。酸化液投加量为20 mg/L时(以TOC计),聚磷菌在好氧吸磷结束时,出水的SP浓度能减少到0.5 mg/L以下。 相似文献
187.
Chemical forms of Zn, Ni, Cu, and Pb in municipal sewage sludge were investigated by adding humus soil to sludge and by
performing sequential extraction procedures. In the final sludge mixtures, Zn and Ni were mainly found in Fe/Mn oxide-bound (F3) and
organic matter/sulfide-bound (F4) forms. For Zn, exchangeable (F1), carbonate-bound (F2), and F3 forms were transformed to F4 and
residual forms (F5). For Ni, F1 and F2 forms were transformed to F1, F2, and F3 forms. Both Cu and Pb were strongly associated with
the stable forms F4 and F5. For Cu, F2 and F3 forms were major contributors, while for Pb, F3 and F4 forms were major contributors to
F5. Humus soil dosage and pH conditions in the sludge were strongly correlated with the forms of heavy metals. Five forms were used
to evaluate metal mobilities in the initial and final sludge mixtures. The mobilities of the four heavy metals studied decreased after 28
days. The metal mobilities in the final sludge mixtures were ranked in the following order: Ni > Zn > Cu = Pb. Leaching tests showed
that the mobilities of Zn and Ni in lower pH conditions (pH 4) were higher than those in higher pH conditions (pH 8). 相似文献
188.
F. Olcay Topac Sagban 《环境科学学报(英文版)》2011,23(4):616-623
The possible impacts on nitrogen-cycle in a p-nitrophenol (PNP) polluted soil and the e ectiveness of wastewater sludge amendments
in restoring nitrification potential and urease activity were evaluated by an incubation study. The results indicated that PNP at 250 mg/kg
soil inhibited urease activity, nitrification potential, arginine ammonification rate and heterotrophic bacteria counts to some extents.
After exposure to PNP, the nitrification potential of the tested soil was dramatically reduced to zero over a period of 30 days. Based
on the findings, nitrification potential was postulated as a simple biochemical indicator for PNP pollution in soils. Nitrogen-cycling
processes in soils responded positively to the applications of wastewater sludges. A sludge application rate of 200 tons/ha was su cient
for successful biostimulation of these nitrogen processes. The microbial activities in sludge-amended, heavy PNP-polluted soils seemed
to recover after 30–45 days, indicating the e ectiveness of sludge as a useful soil amendment. 相似文献
189.
Pretreatment of thickened waste activated sludge (TWAS) by combined microwave and alkaline pretreatment (MAP) was studied to
improve thermophilic anaerobic digestion efficiency. Uniform design was applied to determine the combination of target temperature
(110–210°C), microwave holding time (1–51 min), and NaOH dose (0–2.5 g NaOH/g suspended solids (SS)) in terms of their effect
on volatile suspended solids (VSS) solubilization. Maximum solubilization ratio (85.1%) of VSS was observed at 210°C with 0.2
g-NaOH/g-SS and 35 min holding time. The effects of 12 different pretreatment methods were investigated in 28 thermophilic batch
reactors by monitoring cumulative methane production (CMP). Improvements in methane production in the TWAS were directly related
to the microwave and alkaline pretreatment of the sludge. The highest CMP was a 27% improvement over the control. In spite of the
increase in soluble chemical oxygen demand concentration and the decrease in dewaterability of digested sludge, a semi-continuous
thermophilic reactor fed with pretreated TWAS without neutralization (at 170°C with 1 min holding time and 0.05 g NaOH/g SS)
was stable and functioned well, with volatile solid (VS) and total chemical oxygen demand (TCOD) reductions of 28% and 18%,
respectively, which were higher than those of the control system. Additionally, methane yields (L@STP/g-CODadded, at standard
temperature and pressure (STP) conditions of 0°C and 101.325 kPa) and (L@STP/g VSadded) increased by 17% and 13%, respectively,
compared to the control reactor. 相似文献
190.
Comparative study of heavy metal and pathogenic bacterial contamination in
sludge and manure in biogas and non-biogas swine farms 总被引:1,自引:0,他引:1
Phitsanu Tulayakul Alongkot Boonsoongnern Suwicha Kasemsuwan Srisamai Wiriyaramp Juree Pankumnoe Suwanna Tippayaluck Hathairad Hananantachai RatchaneekornMingkhwan Ramnaree Netvichian Sutha Khaodhiar 《环境科学学报(英文版)》2011,23(6):991-997
The objective of this study is to determine and compare the heavy metal (Zn, Cu, Cd, Pb) and bacterial (E. coli, coliform and
Salmonella spp.) contamination between swine farms utilizing biogas and non-biogas systems in the central part of Thailand. Results
showed that average levels of E. coli, coliform, BOD, COD, Zn, Cu and Pb in sludge from the post-biogas pond were higher than the
standard limits. Moreover, the levels of E. coli, coliform, Cd and Pb were also higher than the standard limits for dry manure. The levels
of E. coli, coliform and BOD on biogas farms were lower than on non-biogas farms. Following isolation of Salmonella spp:; it was
found that Salmonella serovars Rissen was the most abundant at 18.46% (12/65), followed by Anatum 12.31% (8/65), and Kedougou
9.23% (6/65). The pathogenic strains of Salmonella serovars Paratyphi B var. java and Typhimurium were present in equal amounts at
4.62% (3/65) in samples from all swine farms. This study revealed that significant reduction in E. coli and coliform levels in sludge
from covered lagoon biogas systems on swine farms. The presence of Salmonella as well as Cd and Pb, in significant amount in dry
manure, suggests that there is a high probability of environmental contamination if it is used for agricultural purposes. Thus, careful
waste and manure disposal from swine farms and the regular monitoring of wastewater is strongly recommended to ensure the safety
of humans, other animals and the environment. 相似文献