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考察了混合接种不同储存时间及储存方式的好氧颗粒污泥(AGS)的恢复效果。储存后的AGS表现出不同的形态特征:常温湿式储存两年的AGS形态松散, 出现了明显的解体现象;常温湿式储存一年的AGS未出现明显的解体现象, 但颜色明显变黑;琼脂包埋干式储存五个月的硝化颗粒污泥颜色、形态及沉降性能变化不大。重新曝气后, 污泥的MLSS(4.85~10.51 g/L)与MLVSS/MLSS(0.6~0.75)、EPS(15.05~38.36 mg/g MLSS)、平均粒径(0.61~1.12 mm)及颗粒化率(80.92%~97.60%)迅速增大, COD及氨氮去除率也分别在19天与15天上升至90%以上。恢复过程中, 颗粒污泥经历了先破裂后重新颗粒化的过程。根据恢复过程中颗粒污泥的理化特性可知, 混合污泥在21天内成功实现了稳定性及效果恢复。研究结果表明混合部分储存后的硝化颗粒污泥有效提高了硝化细菌的富集速度, 为应用时AGS中硝化细菌的快速富集提供了一种新思路。 相似文献
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为考察好氧颗粒污泥(AGS)对不同pH环境下的耐受力,研究了不同pH废水(pH分别为3、4、5、10、11、12)下AGS的稳定性变化规律.在酸性环境中,AGS的理化特性随pH下降而变差(胞外聚合物(EPS)含量由102.5 mg/g下降到76.43 mg/g MLSS,比耗氧速率(SOUR)由17.94 mg O2/(g MLSS·h))下降到16.19 mg O2/(g MLSS·h)),pH为3和4时均出现不同程度的污泥上浮,对污染物的去除效果也呈下降趋势,但COD和TP的去除率维持在80 %以上.在碱性环境中,AGS出现了明显的上浮及解体.随着pH的增大,AGS的理化特性不断恶化(EPS由93.27 mg/g MLSS上升到178.45 mg/g MLSS,SOUR由6.81 mg O2/(g MLSS·h))下降到4.30 mg O2/(g MLSS·h)).同时,AGS对污染物的去除能力急剧下降,对COD、TN、TP的去除率均下降到50 %以下.研究结果表明AGS在酸性环境中有较强的耐冲击负荷能力,而碱性环境对AGS有较大的抑制作用. 相似文献
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以好氧颗粒污泥(AGS)处理无机高氨氮废水脱氮性能及对钇离子(Y(Ⅲ))吸附效果为研究对象,探索了“好氧+缺氧”模式下自养硝化颗粒污泥(ANGS)的脱氮性能及“好氧+缺氧+好氧”模式下AGS的脱氮性能及短期钇离子冲击下系统稳定性,利用热力学、动力学模型等研究了AGS对Y (Ⅲ)的吸附能力和机理。结果表明,“好氧+缺氧”模式导致混合液悬浮物固体浓度(MLSS)及平均粒径持续减小,通过降低进水氮负荷并补充ANGS使氨氮去除率逐渐增大(3.25%~73.51%);采用“好氧+缺氧+好氧”运行模式并补充AGS后,氨氮去除率超过72.00%(50~72天),MLSS及平均粒径增大,总无机氮(TIN)含量基本保持不变。72天后投入碳源,氨氮去除率减小至40%以下、TIN去除率增大至30%左右。第78天起Y(Ⅲ)浓度在0.01~0.82 mg/L之间,去除率基本稳定在88%以上;通过改变曝气方式和外投碳源后,AGS内Nitrosomonas丰度明显下降(47.43%~11.08%),而Thauera、 unclassified_Chitinophagaceae、 unclassified_Comam... 相似文献
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稀土冶炼有机废水是一种危害性大、水质复杂的高浓度酸性废水,主要污染物包括有机物、氨氮、悬浮物、无机盐、重金属等。因此研究如何有效处理稀土冶炼有机废水对水体、土壤的保护具有重大意义。本研究搭建了序批式膜生物反应器(SBR-MBR),并结合好氧颗粒污泥(Aerobic Granular Sludge,AGS)组成好氧颗粒污泥膜生物反应器(AGS-MBR)。在此基础上,研究了不同碳氮比(有机物中碳与氮的总含量的比值C/N)对AGS-MBR处理工艺的影响。结果表明,在C/N=10时,好氧颗粒污泥稳定性最好,对COD、NH4+-N、TN和TP的脱除率稳定后可达99.0%、96.7%、79.3%、91.1%;进水C/N的降低对AGS-MBR去除COD的影响较小,对出水N的形态和TP影响较大,并且当C/N≤7时,部分好氧颗粒污泥发生解体,出水TN和TP浓度达到《城镇污水处理厂污染物排放标准》GB 18918—2002(2006)一级A排放标准要求,为进一步探讨研究更低C/N的稀土冶炼有机废水的处理工艺提供理论依据。 相似文献
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准好氧填埋场稳定化指标的室内模拟研究 总被引:1,自引:0,他引:1
准好氧填埋场是传统填埋场可持续发展的一个重要的方向,本文结合准好氧填埋场的室内模拟实验结果以及理论分析,提出了准好氧填埋场稳定化评价指标的四条选取原则,在模拟实验的基础上,从渗滤液性质、垃圾降解特性、填埋场地沉降三个方面建立了准好氧的评价指标体系,所包含的指标有:渗滤液COD、氨氮、TVS/TDS,固相垃圾BDM,场地沉降量。 相似文献
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Aerobic granular sludge technology was applied to the simultaneous nitrogen and phosphorus removal from livestock wastewater that contains high concentrations of nitrogen and phosphorus (TN: 650?mg/L; TP: 125?mg/L). A lab-scale sequencing batch reactor was operated in an alternating anaerobic/oxic/anoxic denitrification mode. Granular sludge was first formed using synthetic wastewater. When livestock wastewater was diluted with tap water, the shape and settleability of aerobic granular sludge were maintained even though livestock wastewater contained suspended solids. Simultaneous nitrification, denitrification, and phosphate uptake were observed under an aerobic condition. However, when nondiluted livestock wastewater was used, the diameter of granular sludge and the denitrification efficiency under an oxic condition decreased. When the concentrations of nitrogen and phosphorus in wastewater increased, hydraulic retention time (HRT) increased resulting in a decrease in selection pressure for granular sludge. Therefore, the sustainment of granular sludge was difficult in livestock wastewater treatment. However, by applying a new excess sludge discharge method based on Stokes’ law, the shape of granular sludge was maintained in spite of the long HRT (7.5?days). To select large granular sludge particles, excess sludge was discharged from the upper part of settled sludge because small particles localized there after settling. Finally, excellent nitrogen and phosphorus removal was accomplished in practical livestock wastewater treatment. The effluent concentrations of NH4–N, NOx–N, and PO4–P were <0.1, 1.4, and 1.2?mg/L, respectively. 相似文献
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Combined cultures were developed from anaerobic granular and suspended aerobic cultures in three upflow sludge blanket reactors aerated at 10?mL air/min 4?h/day (R2), every other day (R3), and 24?h/day (R4). The use of combined cultures was found to be advantageous compared to the anaerobic granules for the treatment of low-strength wastewaters. During municipal wastewater treatment at influent 5-day biochemical oxygen demand (BOD5) concentration of 53–118?mg/L (hydraulic retention time: 0.75?day), combined cultures in R2, R3, and R4 exhibited average BOD5 removal efficiencies of 52, 75, and 76%, respectively. The use of these cultures might be proposed as an alternative for municipal wastewater treatment due to their advantages such as achievement of required discharge standards, prevention of biomass loss/settleability problems unlike activated sludge systems and possible methanogenic activity, as well as high settling characteristics comparable to those of anaerobic granules. 相似文献
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Bench-scale experiments investigated the effect of electrolyte mixing on the effectiveness of an electrochemical reactor for the reactivation of granular activated carbon (GAC). Two different GACs (F-400 and WV-B) were loaded with phenol via batch adsorption tests, then electrochemically reactivated and finally reloaded with phenol. Reactivation was conducted in a recirculating flow reactor with a 0.1?M NaCl solution as the electrolyte. Cathodic reactivation was more efficient than the anodic reactivation and increasing the degree of electrolyte mixing decreased the cathodic reactivation efficiencies, while there was no significant change in the anodic reactivation efficiencies. Higher degrees of electrolyte mixing decreased the local pH at the cathode and consequently reduced the desorption driving force and therefore reduced the reactivation efficiency. The electrolyte mixing lowered the cell voltage. However, this advantage was overshadowed by the increased energy consumption required for the electrolyte pumping, the reduction of the oxidation rate of phenol, and a 20% reduction in the reactivation efficiencies. Thus, electrolyte mixing of the electrolyte is not recommended in the electrochemical reactivation of GAC. 相似文献
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Laboratory-scale experiments were conducted to determine optimum sludge residence time (SRT) and temperature of aerobic thermophilic pretreatment (ATP) of mixed sludge (thickened waste activated sludge and primary sludge) to achieve maximum pathogen reduction and best process performance. 4-L laboratory-scale ATP reactors were operated at SRTs of 0.6, 1.0, and 1.5 days and temperatures of 55, 58, 62, and 65°C. ATP at temperatures ≥62°C and SRT ≥0.6 day reduced the feed sludge fecal coliform density from 107 MPN∕g total solids (TS) to <104 MPN∕g TS. Salmonella in the feed sludge was reduced to <1 MPN∕4 g TS from 2 to 18 MPN∕4 g TS by ATP at temperatures ≥55°C and SRT ≥0.6 day. ATP was able to increase sludge volatile acids concentration by 100–200% over the feed sludge volatile acid concentration and to reduce sludge supernatant chemical oxygen demand from 20,000 to 22,000 mg∕L in the feed to 13,000–17,000 mg∕L in the ATP reactor. Volatile solids reduction by ATP increased from 25 to 40% when SRT was increased from 0.6 to 1.5 days, and a 5% increase in volatile solids reduction was seen at SRTs of 0.6, 1.0, and 1.5 days when ATP temperature was increased from 55 to 65°C. 相似文献
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The objective of this research was to investigate the effectiveness of aerobic thermophilic treatment in enhancing conventional anaerobic mesophilic digestion in terms of pathogen reduction. vector attraction reduction, volatile solids (VS) reduction, gas production, and product sludge dewaterability. Lab-scale two-stage experiments were conducted with the aerobic thermophilic stage as pretreatment (AerTAnM) or as posttreatment (AnMAerT) to mesophilic anaerobic digestion. The lab-scale AerTAnM and AnMAerT systems were operated at system sludge residence times (SRTs) of 15 and 15.5 days, thermophilic reactor temperature = 62°C, and mesophilic reactor temperature = 37°C. The control anaerobic digester was operated at a system SRT of 15 and 15.5 days and temperature = 37°C. The AerTAnM and AnMAerT systems and control anaerobic digester operated at a system SRT of 15 days were able to achieve VS reductions of >38% (Class A sludge vector attraction reduction requirement). The VS reductions by the AerTAnM and AnMAerT systems (~65%) were higher than the VS reduction in the control (~51%) by 14%. The AerTAnM and AnMAerT systems reduced fecal coliform density in the feed sludge from 108 most probable number (MPN) per gram of total solids (TS) to <103 MPN∕g TS (Class A sludge fecal coliform density limit), whereas the control reduced the same feed sludge fecal coliform density to about 106 MPN∕g TS. The AerTAnM and AnMAerT systems and control can reduce Salmonella density in the feed sludge from 5 to 12 MPN∕4 g TS to <1 MPN∕4 g TS. Average methane gas production by the AerTAnM system anaerobic mesophilic digester (0.61 m3∕kg VS destroyed) was higher than those of the AnMAerT system (0.50 m3∕kg VS destroyed) and control (0.52 m3∕kg VS destroyed) anaerobic mesophilic digesters. Average H2S content of the AerTAnM [133 ppm volume-to-volume ratio (v∕v)] system anaerobic thermophilic digester gas was significantly lower than those in gas from the AnMAerT system (249 ppm v∕v) and control (269 ppm v∕v) anaerobic mesophilic digesters. The dewaterabilities of the product sludge (measured as time-to-filter, s) from the AerTAnM system (237 s) and AnMAerT system (203 s) were significantly better than that of the product sludge from the control (346 s). 相似文献
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The formation and characteristics of intracellular polymers in aerobic sludge of sequencing batch reactors were investigated at ambient temperature under balanced nutrient conditions. Three substrates of different chemical natures, including fatty acid (acetate), carbohydrate (glucose), and aromatic (benzoate), were fed to individual reactors. When substrates were initially in excess, the sludge in all reactors was capable of converting soluble substrates into intracellular polymers under aerobic conditions. Acetate (up to 27%) and benzoate (up to 51%) were converted to poly-β-hydroxybutyrate, whereas glucose (up to 33%) was converted to intracellular carbohydrates. The initial substrate depletion rates were 208–243 mg-C∕g-VSS∕h for acetate, 491–590 mg-C∕g-VSS∕h for benzoate, and 405–558 mg-C∕g-VSS∕h for glucose. When external substrates were absent in the mixed liquor, the intracellular polymers could be consumed by the sludge for endogenous respiration under aerobic conditions or as a carbon source for denitrification under anoxic conditions. These results suggest a dynamic metabolic mechanism in the sequencing batch reactors. 相似文献
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Response of an aerobic upflow sludge blanket (AUSB) reactor system to the changes in operating conditions was investigated by varying two principle operating variables: the oxygenation pressure and the flow recirculation rate. The oxygenation pressure was varied between 0 and 25?psig (relative), while flow recirculation rates were between 1,300 and 600% correspondingly. The AUSB reactor system was able to handle a volumetric loading of as high as 3.8?kg total organic carbon (TOC)/m3?day, with a removal efficiency of 92%. The rate of TOC removal by AUSB was highest at a pressure of 20?psig and it decreased when the pressure was increased to 25?psig and the flow recirculation rate was reduced to 600%. The TOC removal rate also decreased when the operating pressure was reduced to 0 and 15?psig, with corresponding increase in flow recirculation rates to 1,300 and 1,000%, respectively. Maintenance of a high dissolved oxygen level and a high flow recirculation rate was found to improve the substrate removal capacity of the AUSB system. The AUSB system was extremely effective in retaining the produced biomass despite a high upflow velocity and the overall sludge yield was only 0.24–0.32?g VSS/g TOC removed. However, the effluent TOC was relatively high due to the system’s operation at a high organic loading. 相似文献
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重点研究了pH对污泥发酵的影响,研究结果表明:酸性pH(4~5)对产酸菌和产甲烷菌都有抑制作用,pH越小,抑制作用越大;碱性pH能促进水解,并且对产酸菌和产甲烷菌的抑制作用很小,故碱性对污泥发酵最有利。 相似文献