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厌氧生物法废水处理技术进展 总被引:2,自引:0,他引:2
阐明了厌氧生物法处理废水的特征,并着重介绍了厌氧接触反应器、厌氧流化床反应器、厌氧膨胀床反应器.厌氧生物转盘和厌氧污泥床反应器在各种厌氧生物法处理废水工艺中的应用情况。 相似文献
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将处理柠檬酸废水的内循环厌氧反应器的出水以不同比例回流至水解酸化池,研究了厌氧出水回流对水解酸化过程及厌氧处理过程的影响。实验结果表明:厌氧出水参与水解酸化能明显提高水解酸化池的出水pH及废水的预酸化度,厌氧出水添加比(V(厌氧出水)∶V(废水))为1∶4及以上时,可使水解酸化池的出水pH稳定在4.5以上,同时达到10.0%以上的预酸化度,且对NH3-N的去除能力明显增强;随水解酸化时间的延长,水解酸化池的出水pH先减小后增大,而预酸化度则呈上升趋势;水解酸化3.0 h时,厌氧出水COD降至1 200 mg/L以下。厌氧出水参与水解酸化能增强厌氧反应器中微生物对挥发性脂肪酸的利用率,提高厌氧反应器出水的pH,降低出水COD及其波动幅度,增强厌氧系统的稳定性及自我修复能力。 相似文献
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将处理柠檬酸废水的内循环厌氧反应器的出水以不同比例回流至水解酸化池,研究了厌氧出水回流对水解酸化过程及厌氧处理过程的影响。实验结果表明:厌氧出水参与水解酸化能明显提高水解酸化池的出水pH及废水的预酸化度,厌氧出水添加比(V(厌氧出水)∶V(废水))为1∶4及以上时,可使水解酸化池的出水pH稳定在4.5以上,同时达到10.0%以上的预酸化度,且对NH3-N的去除能力明显增强;随水解酸化时间的延长,水解酸化池的出水pH先减小后增大,而预酸化度则呈上升趋势;水解酸化3.0 h时,厌氧出水COD降至1 200 mg/L以下。厌氧出水参与水解酸化能增强厌氧反应器中微生物对挥发性脂肪酸的利用率,提高厌氧反应器出水的pH,降低出水COD及其波动幅度,增强厌氧系统的稳定性及自我修复能力。 相似文献
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为了有效的减少新诺明废水在生化处理中产生的泡沫,研究了生物泡沫及化学泡沫控制措施.实验结果表明:将进水方式由多点喷淋进水改成单点中部进水,按m(C):m(P)=100:1投加磷肥、控制MLSS为2500~3000 mg/L、连续投加NaClO溶液5d,使泡沫体积由原来的95 mL减少到39 mL,生物泡沫得到了有效控制;采用厌氧工艺,当厌氧污泥MLSS为30000 mg/L、厌氧停留时间为6d时,泡沫体积从110mL减少到43 mL,化学泡沫得到有效控制. 相似文献
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涤纶厂聚酯废水的生化处理 总被引:2,自引:0,他引:2
本文简述了涤纶厂聚酯废水的特点,介绍了对这种废水的三种生化处理方法(活性污泥法,生物塔滤-生物流化床法,氧化沟-厌氧-生物接触氧化法)及其优缺点,并较详细地介绍了氧化沟-厌氧-生物接触氧化法的处理工艺。 相似文献
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A dynamic leaching method for the assessment of trace metals released from hydraulic binders 总被引:2,自引:0,他引:2
Moudilou E Bellotto M Defosse C Serclerat I Baillif P Touray JC 《Waste management (New York, N.Y.)》2002,22(2):153-157
With respect to sustainable development, the leachability of trace metal from solid materials in contact with water has focused much attention over the years. Portland cements produced in industrial kilns generally contain from 10 to 300 mg/kg of trace metals. The behaviour of these endogenous metals has been, in this regard, the target of different leaching studies. Many of these researches concluded that heavy metals release are lower than analytical detection limits. Although satisfying from an environmental point of view, it induces a lack in the knowledge about the trace metals behavior during the leaching of cement based material. Accordingly, we designed the CTG-LEACHCRETE device, a dynamic leaching system (modified Soxhlet type) that overcomes this difficulty and allows long term monitoring. The experimental procedure is presented and preliminary results are discussed. 相似文献
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Thermodynamic analysis of the role of chlorine and sulfur environments during combustion and incineration processes 总被引:1,自引:0,他引:1
Iddi S.N. Mkilaha Hong Yao Ichiro Naruse 《Journal of Material Cycles and Waste Management》2002,4(2):143-149
In order to control the emission of trace metals from combustion and incineration systems, sorbents and filters are sometimes
used. However, the effectiveness of these methods is greatly affected by the volatility of the metals and the way in which
they speciate during combustion, and afterwards during condensation, and physical or chemical sorption. Although there has
been a lot of research into the mechanisms by which trace metals speciate and subsequently appear in submicron particles,
the details of these mechanisms are not yet thoroughly understood. In this study, a chemical equilibrium approach was used
to qualitatively determine the speciation of lead, cadmium, and chromium in Cl and S environments. The reaction conditions
of sorbents were also tested numerically in order to understand the reaction behavior of metals with sorbents. This article
reports the influence of different concentrations of Cl and SO2 on Pb, Cd, and Cr speciation, as representatives of other trace elements. The partitioning behavior of metals during combustion
was also examined for Cl and S. The results obtained indicate that most metals exist in the vapor phase, even at low temperatures,
when chlorine is present. However, the addition of SO2 enhances the formation of the condensed phase, except at extremely high temperatures. This observation was not significant
for Cd or Cr. The higher the concentration of Cl the higher the retention of trace metals in the vapor phase, even at low
temperatures. Results from comparisons of the reactivities of mixed metals with Cl indicate that the presence of Fe limits
the reactivity of most trace metals with Cl except at higher concentrations. In the presence of Fe, alkali metals are the
first to react with Cl. If Fe is not present, most trace metals react with Cl, and the activity increases with higher concentrations.
On the other hand, the partitioning characteristics of S show that its presence generally means that metals remain in the
condensed phase. Sulfur is more reactive with alkali metals than with other trace metals.
Received: June 6, 2001 / Accepted: April 30, 2002 相似文献
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土壤-植物系统重金属形态分析和生物有效性研究进展 总被引:62,自引:0,他引:62
介绍了土壤-植物系统中重金属连续提取的形态分析方法研究进展,同时归纳了影响重金属生物有效性的主要因素,如土壤性质、复合污染及根际环境等,并指出了需要解决的问题与今后的发展方向。 相似文献
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Elvis G. Ngwenya Maud Walsh Caroline A. Metosh‐Dickey Ralph J. Portier 《补救:环境净化治理成本、技术与工艺杂志》2006,16(2):79-90
Biological and physicochemical approaches were utilized in a treatment train for acid mine dis charge (AMD) waters. Anaerobic bioreactors, chemical precipitation reactors, and biopolymer chelation reactors, operated in static, semicontinuous, and continuous flow modes, removed significant quantities of metals and sulfates associated with AMD water. Static tests indicated accept able copper removal via precipitation by generation of hydrogen sulfide in anaerobic reactors. However, low pH affected the biopolymer coating in the chelation reactor, resulting in loss of bed surface. Corrections of AMD to pH > 7 resulted in some metal precipitationprior to biopolymer treatment. A series of static semicontinuous tests at pH 5.0 provided improved metal and sulfate removal. Copper (Cu+) was reduced to trace concentrations, while manganese (Mn+), although reduced, proved to be the most recalcitrant of the metals. © 2006 Wiley Periodicals, Inc. 相似文献
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The purpose of this study was to examine if long-term anaerobic digestion of food waste in a semi-continuous single-stage reactor could be stabilized by supplementing trace elements. Contrary to the failure of anaerobic digestion of food waste alone, stable anaerobic digestion of food waste was achieved for 368 days by supplementing trace elements. Under the conditions of OLR (organic loading rates) of 2.19-6.64 g VS (volatile solid)/L day and 20-30 days of HRT (hydraulic retention time), a high methane yield (352-450 mL CH(4)/g VS(added)) was obtained, and no significant accumulation of volatile fatty acids was observed. The subsequent investigation on effects of individual trace elements (Co, Fe, Mo and Ni) showed that iron was essential for maintaining stable methane production. These results proved that the food waste used in this study was deficient in trace elements. 相似文献
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Anaerobic biotransformation and methane generation potential of cheese whey in batch and UASB reactors. 总被引:5,自引:0,他引:5
Anaerobic treatability and methane generation potential of cheese whey were determined in batch reactors. Furthermore, the effect of nutrient and trace metal supplementation on the batch anaerobic treatment, and the high-rate anaerobic treatability of cheese whey in upflow anaerobic sludge blanket (UASB) reactors were investigated. To this purpose biochemical methane potential experiments were conducted and single- and two-stage UASB reactors with granular cultures were operated. In UASB experiments significance of process staging, operational parameters such as hydraulic retention time (HRT), influent chemical oxygen demand (COD) concentration and loading rate were also investigated. The results revealed that nutrient and trace metal supplementation is vital for the anaerobic treatment of cheese whey; the anaerobic methane generation for the cheese whey studied was found to be 424 ml CH4/g COD (23.4 1 CH4/l cheese whey); undiluted cheese whey could be treated anaerobically at relatively short HRT values (2.06-4.95 days) without any significant stability problems; HRT values as low as 2-3 days can be used for the anaerobic treatment of cheese whey, with a COD removal efficiency of 95-97% at influent COD concentration of 42 700 +/- 141-55 100 +/- 283 mg/l. 相似文献
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Accumulation and fate of selected heavy metals in a biological wastewater treatment system 总被引:10,自引:0,他引:10
Chipasa KB 《Waste management (New York, N.Y.)》2003,23(2):135-143
The aim of this research was to study the accumulation and removal of heavy metals (Cd, Cu, Pb, Zn) by a biological wastewater treatment system. Heavy metal contents in the influent and effluent wastewater were compared. Also, the heavy metal contents in the sludge before and after anaerobic digestion were compared. The results showed: (1) more pronounced variations in the contents of Cu and Zn than that of Cd and Pb, which showed that at 0.02 for Cd and 0.05 mg/l for Pb, the reduction in their contents was insignificant; (2) that removal of heavy metals was directly proportional to their initial contents in the influent wastewater. Corresponding to the influent contents, in increasing order, the reduction in heavy metal contents was: Cd相似文献
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Kevin A. Morris 《补救:环境净化治理成本、技术与工艺杂志》2009,20(1):59-68
Mulch biowalls are proving to be an effective means of generating reducing conditions for the in situ anaerobic reduction of contaminants in groundwater that are amenable to the reduction process. Mulch is an inexpensive and readily available substrate that provides a long‐lasting carbon and electron donor source for the stimulation of the anaerobic reduction process in groundwater. Examples of contaminants that are amenable to the biotic anaerobic reduction process include: chlorinated alkenes and alkanes, explosives, perchlorate, some metals, and petroleum hydrocarbons. The microbial degradation of cellulose fibers (mulch) is arguably the oldest reduction process known and is evident anywhere that plant material, soil, and water are present together. This article presents three case studies discussing three different uses of mulch biowalls to stimulate the anaerobic bioremediation of contaminants in shallow soils and groundwater. © 2009 Wiley Periodicals, Inc. 相似文献
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Fixation and partitioning of heavy metals in slag after incineration of sewage sludge 总被引:3,自引:0,他引:3
Fixation of heavy metals in the slag produced during incineration of sewage sludge will reduce emission of the metals to the atmosphere and make the incineration process more environmentally friendly. The effects of incineration conditions (incineration temperature 500-1100°C, furnace residence time 0-60min, mass fraction of water in the sludge 0-75%) on the fixation rates and species partitioning of Cd, Pb, Cr, Cu, Zn, Mn and Ni in slag were investigated. When the incineration temperature was increased from 500 to 1100°C, the fixation rate of Cd decreased from 87% to 49%, while the fixation rates of Cu and Mn were stable. The maximum fixation rates for Pb and Zn and for Ni and Cr were reached at 900 and 1100°C, respectively. The fixation rates of Cu, Ni, Cd, Cr and Zn decreased as the residence time increased. With a 20min residence time, the fixation rates of Pb and Mn were low. The maximum fixation rates of Ni, Mn, Zn, Cu and Cr were achieved when the mass fraction of water in the sludge was 55%. The fixation rate of Cd decreased as the water mass fraction increased, while the fixation rate of Pb increased. Partitioning analysis of the metals contained in the slag showed that increasing the incineration temperature and residence time promoted complete oxidation of the metals. This reduced the non-residual fractions of the metals, which would lower the bioavailability of the metals. The mass fraction of water in the sludge had little effect on the partitioning of the metals. Correlation analysis indicated that the fixation rates of heavy metals in the sludge and the forms of heavy metals in the incinerator slag could be controlled by optimization of the incineration conditions. These results show how the bioavailability of the metals can be reduced for environmentally friendly disposal of the incinerator slag. 相似文献
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Evaluation of heavy metal content in digestate from batch anaerobic co-digestion of sunflower hulls and poultry manure 总被引:1,自引:0,他引:1
Burak Demirel Nefise Pınar Göl Turgut Tüzün Onay 《Journal of Material Cycles and Waste Management》2013,15(2):242-246
In this experimental study, the biogas digestate from mesophilic batch anaerobic co-digestion of poultry manure and an agricultural residue, sunflower hulls, was characterized, particularly in terms of heavy metal content, in order to evaluate whether the biogas digestate was suitable for land applications. Ni, Zn, Cu, Pb, Cr, Cd, and Hg were detected in the biogas digestate in each trial, however, their concentrations were always lower than the limit values stated in Turkish regulations. The main source of heavy metals in the biogas digestate seemed to be the poultry manure, not the agricultural residue. The commercial feedstuffs that are frequently supplemented with various essential elements to promote optimum nutrient supply and optimum growth rates may have contributed to heavy metals presence in the biogas digestate. The results indicated that the biogas digestate from anaerobic co-digestion of manure and agricultural residue could be utilized as fertilizer in agricultural applications. 相似文献