共查询到19条相似文献,搜索用时 125 毫秒
1.
本研究旨在探索用电解浮选进行活性污泥固液分离的可行性。研究通过小试试验确定电解浮选进行活性污泥固液分离的适宜工艺条件,在装有Ti/RuO2-IrO2-TiO2阳极、Ti阴极的电解浮选槽中进行了活性污泥固液分离的研究,针对影响电解气浮工艺的4个主要影响因素(水力停留时间、接触室电流密度、分离区电流密度和接触室极板间距)及3个合适的水平进行正交试验。结果表明,分离区电流密度是最主要影响因素。当进水SS浓度为1687 mg/L时,在停留时间为25 min,接触室电流密度为5 mA/cm2,分离区电流密度为4 mA/cm2,极板间距为3 mm的条件下进行电解浮选验证性试验,悬浮固体颗粒物去除率较高,去除率为98.9% ,能耗0.54 kWh/m3。 相似文献
2.
分别用3种不同材料电极(不锈钢、Ti/Pt和Ti/RuO2-IrO2)作阳极、石墨电极作阴极在同一条件下分别对循环式准好氧填埋垃圾场渗滤液进行电解处理对比研究.研究结果表明,随着电解时间的变化,渗滤液中的COD、BOD5、BOD5/COD、重金属离子浓度、色度和pH值均会发生改变.当电解时间为10~20 min时,用上述3种电极作阳极电解均会出现渗滤液COD、BOD5、BOD5/COD增大的现象;当电解时间为30~40 min时,用Ti/RuO2-IrO2或Ti/Pt电极作阳极电解均可使渗滤液的色度降为0;当电解时间为120 min时,分别用3种电极作阳极电解都可使渗滤液中的COD、BOD5和重金属得到有效的去除,其中用Ti/RuO2-IrO2电极作阳极电解对COD、BOD5的去除效果最好:用Ti/Pt电极作阳极电解对Pb2 的去除效果最好. 相似文献
3.
La掺杂SnO2/Ti电极电催化降解邻硝基苯酚 总被引:2,自引:1,他引:2
采用凝胶一溶胶法制备了La掺杂SnO2/Ti电极并用于邻硝基苯酚废水的电解研究.分析了电流密度、电极距离、溶液初始pH对邻硝基苯酚电解效果的影响,确定了最佳电解条件.结果表明,La/Sn(摩尔比)为0.03,热处理温度为450℃下制备的La掺杂SnO2/Ti电极对邻硝基苯酚的降解效果最好.当电流密度为20 mA/cm2,电极距离为2 cm,溶液初始pH为6~7时,电解180 min后的邻硝基苯酚的降解率可达95.1%.利用液相色谱和离子色谱检测了邻硝基苯酚电解产物,并初步分析了邻硝基苯酚的降解途径. 相似文献
4.
针对罐底油泥水洗过程中存在的油相与固相分离难度大、回收的油分中含固率与含水率较高2个关键问题,研究了以“球磨+浮选”为核心的联合工艺的处理效果。对球磨和浮选工艺参数进行优化后,确定球磨段的最优处理条件为球磨温度45 ℃,液固比3∶1,球磨处理时间30 min,球磨药剂用量0.8%;浮选段的最优处理条件为浮选温度55 ℃、液固比4∶1、浮选时间35 min、浮选药剂用量0.6%。结果表明:在最优条件下,处理后罐底油泥的固体出料含油率可降低到0.8%,达到了 SY/T 7301-2016中规定的处理处置要求;处理过程中得到的原油经过油品纯化后,含水率与含固率均低于0.5%,可在炼厂进行回收利用。以“球磨+浮选”为核心的联合工艺较好地解决了罐底油泥在水洗过程中暴露出来的2个问题,为罐底油泥的无害化、资源化处理提供了参考。 相似文献
5.
电极材料对电解法处理循环式准好氧垃圾填埋场渗滤液效果的影响研究 总被引:1,自引:0,他引:1
分别用3种不同材料电极(不锈钢、Ti/Pt和Ti/RuO2-IrO2)作阳极、石墨电极作阴极在同一条件下分别对循环式准好氧填埋垃圾场渗滤液进行电解处理对比研究。研究结果表明,随着电解时间的变化,渗滤液中的COD、BOD5、BOD5/COD、重金属离子浓度、色度和pH值均会发生改变。当电解时间为10—20min时,用上述3种电极作阳极电解均会出现渗滤液COD、BOD5、BOD5/COD增大的现象;当电解时间为30—40min时,用Ti/RuO2-IrO2或Ti/Pt电极作阳极电解均可使渗滤液的色度降为0;当电解时间为120min时,分别用3种电极作阳极电解都可使渗滤液中的COD、BOD5和重金属得到有效的去除,其中用Ti/RuO2-IrO2电极作阳极电解对COD、BOD5的去除效果最好:用Ti/Pt电极作阳极电解对Pb^2+的去除效果最好。 相似文献
6.
采用PbO2/Ti和IrO2-Ta2O5/Ti电极对酸性橙7(AO7)模拟废水进行了电解处理实验研究。考察了2种电极上不同电流密度条件下AO7的去除率、反应动力学、COD去除效果及瞬时电流效率,结果表明,在相同条件下,PbO2/Ti电极表现出更好的处理效率、更适合用于AO7的矿化。循环伏安(CV)曲线表明,PbO2/Ti电极具有更高的析氧电位且在AO7电解液中出现了氧化峰,说明PbO2/Ti电极对AO7具有更好的催化活性和直接氧化能力。紫外可见光谱对比分析表明,IrO2-Ta2O5/Ti电极对AO7的结构破坏速度缓慢且伴随苯胺等中间产物产生,对AO7的矿化程度弱。对比结果说明PbO2/Ti电极更适合于偶氮类染料废水的电催化氧化处理。 相似文献
7.
研究通过单因素分析和正交实验法确定新型微电解填料-Fenton联用预处理硝基苯废水的最佳操作条件。结果表明,新型微电解填料降解硝基苯的影响因素从大到小依次为固液比 > 进水pH值 > 气水比 > HRT,在微电解最佳条件:HRT为60 min,固液比为0.6,进水pH值为2,气水比为15:1;Fenton试剂最佳条件:反应时间为20 min、pH值为4.5、m(H2O2):m(COD)为2.5、n(H2O2):n(Fe2+)为6,硝基苯和COD总去除率可分别达到97.6%和68.3%。处理后的废水可生化性提高,为后续的生物处理创造了良好的条件。 相似文献
8.
通过植物泥培筛选实验、植物密度实验和水力停留时间优化实验对4种沉水植物进行筛选并研究了植物的最佳种植密度和生物降固装置对水体悬浮物和总氮的净化效果。结果表明:穗花狐尾藻适应能力较强,在北方冬季低温环境下仍能继续生长;种植密度为100株·m-2的穗花狐尾藻对悬浮物的吸附和截留作用最明显;生物降固装置最佳HRT为6~8 h。在HRT为6 h条件下,植物组对悬浮物的去除率为78.6%,比对照组高39%;总氮去除率为8.9%,说明生物降固装置可以有效截留、吸附悬浮物,但在较短HRT条件下对总氮吸附作用不明显。悬浮物达到同样去除效果,生物降固装置比自然沉降需要的时间少2~4 h。同时,种植水生植物的生物降固装置对总氮有一定的去除效果,降低人工湿地进水氮负荷。 相似文献
9.
10.
粉煤灰对Cr(Ⅵ)的吸附特性 总被引:1,自引:0,他引:1
通过间歇实验研究了粉煤灰对重金属Cr(Ⅵ)的吸附特性.探讨了固液比、pH、反应时间、温度、离子强度和初始浓度等因素的影响.实验结果表明,固液比、pH、温度与离子强度都对去除率有较大影响.当温度为20℃、pH=1、Cr(Ⅵ)的初始浓度为10 mg/L,固液比为100 g/L时,去除率达到50.13%.动力学实验结果表明,粉煤灰对Cr(Ⅵ)的吸附为快速反应,在180 min内可达到平衡,伪二级动力学模型可较好地拟合实验结果.等温吸附实验结果表明,Freundlich模型与Langmuir模型均可较好地拟合等温吸附实验结果.低温有助于粉煤灰对Cr(Ⅵ)的吸附. 相似文献
11.
受微通道分离介质再生后截滤残留污染物影响,常规微通道分离效率持续衰减,成为抑制微通道分离广泛高效应用的关键瓶颈。通过开发旋流振荡再生单元,研究了旋流振荡再生强度和振荡再生结构对微通道分离装置过滤介质再生效率的影响,由此集成研发沸腾床分离器,考察了装置对实际含油污水的分离效率,并分析了微通道振荡再生对沸腾床分离的强化原理以及装置的分离经济性。结果表明,当再生强度为5.0 L·(s·m2)−1时、再生15 min后采用轴向振荡再生结构,沸腾床分离器达到最佳再生工况。在最佳再生工况下开展10 m3·h−1实际含油污水连续处理实验,针对油质量浓度为30~200 mg·L−1、悬浮物质量浓度为25~200 mg·L−1的来水,装置出水平均油分和悬浮物质量浓度分别降至11.4 mg·L−1和23.5 mg·L−1,并可在来水最高油质量浓度和悬浮物质量浓度接近50 000 mg·L−1的冲击工况下,确保出水平均油分和悬浮物质量浓度降至15.9 mg·L−1和29.8 mg·L−1。利用沸腾床分离器再生结构中旋流诱导的过滤介质表界面污染物振荡运动,分离过程中截滤残留的油分和悬浮物等污染物被及时脱附,实现颗粒介质表界面彻底更新,确保装置长周期稳定运行。以200 m3·h−1规模实际含油污水处理为例,沸腾床分离工艺相对涡凹气浮和溶气气浮的组合工艺,可完全取消化学絮凝药剂消耗且不产生化学浮渣,且具有显著的经济环保效益。 相似文献
12.
The difference in performance of three differently designed circular secondary clarifiers in the same wastewater treatment plant was analyzed in this paper. Data obtained using flocculated suspended solids and disperse suspended solids tests were analyzed using statistical tools. The conventional clarifier showed more variability in the average effluent suspended solids concentration when compared with the flocculator-clarifiers. Furthermore, a difference in performance among the two different flocculator-clarifiers was found. 相似文献
13.
Characteristics and behavior of raw and digested mixed liquor derived from a membrane bioreactor (MBR) and a full-scale activated-sludge (FSAS) facility were compared. The accumulation of nondegradable chemical oxygen demand in the MBR appears to play an important role in increasing the observed biological yield coefficient (Y(obs)), reducing average floc size, decreasing total suspended solids/total solids and volatile suspended solids/volatile solids (VS) ratios, and reducing specific-oxygen-uptake rates of the mixed liquor relative to FSAS-derived biological solids. Membrane bioreactor sludges exhibited lower VS destruction following 30 days mesophilic-anaerobic and aerobic digestion when compared to FSAS sludges. Significant deterioration in dewatering behavior was observed for the FSAS biosolids after anaerobic digestion and, to a lesser extent, following aerobic digestion. In comparison, digestion had a small affect on dewatering efficiency and conditioner requirements for MBR biosolids. Full-scale facilities using membrane separation may need to tailor digestion and dewatering processes to the specific characteristics of MBR sludges. 相似文献
14.
《国际环境与污染杂志》2011,30(2):332-344
A pilot-scale electroflotation system with a treatment capacity of 0.8 m³ per hour has been designed and built. The system is equipped with a conditioning tank, a rectifier, flow meters, an energy meter and pumps. Iron, aluminium and titanium coated with oxides of tantalum, ruthenium and iridium were used as electrodes. The system was installed within the premises of the Common Effluent Treatment Plant (CETP), which receives effluents from nearly 200 tanneries. The effectiveness of electroflotation for the separation of suspended solids, sulphur species, chromium and other chemicals contributing to COD and BOD were studied. The separation of suspended solids and chromium by electroflotation was nearly complete (>95%) and their concentration in the processed samples can be maintained well below the discharge limits. The removal of COD was observed to be 15–20% greater than with conventional chemical coagulation. Furthermore, the entire spectrum of pathogenic bacteria was eliminated to the extent of 99.97% by subjecting the effluent to electroflotation. 相似文献
15.
Daniel P. Smith Ph.D. P.E. 《Journal of the Air & Waste Management Association (1995)》2013,63(6):502-509
Abstract Nitrogen transformations and their effect on aerobic suspended growth treatment of an industrial wastewater were studied in three parallel bench-scale reactors operated at 5 "C at mean cell residence times (MCRT) of 15, 30, and 60 days. In normal process wastewater, the bulk of influent nitrogen was in organic form, and the fraction transformed was almost totally incorporated into synthesized biomass. Assimilative control by heterotrophs maintained ammonianitrogen levels below permitted effluent levels, and nitrification was not significant. Although volatile suspended solids had a nitrogen content of only 5% to 8%, effective organics removal was maintained, and total organic carbon and filtered daily average five-day biochemical oxygen demand (BODS) were below permitted effluent levels. A marked improvement in settleability and lower effluent total suspended solids was achieved by adding ammonia-nitrogen to the wastewater in excess of stoichiometric growth requirements. During a batch production cycle of a cationic chemical, the ratio of nitrogen to chemical oxygen demand and the fraction of the total influent nitrogen in soluble form increased in the wastewater. Reactor effluent ammonia levels increased to above permit levels at all three MCRTs during treatment of wastewater containing cationic production effluents. The magnitude of ammonia increase was greater for longer MCRTs, suggesting that synthesis of cell mass was not capable of assimilating the increased ammonia supply under these non-steady conditions. The experimental results suggest several potential strategies for operating the aerobic process at the treatment facility, including adding nitrogen to improve settleability and discontinuing these additions when wastewater contains a high ratio of nitrogen to chemical oxygen demand and an elevated soluble nitrogen fraction 相似文献
16.
Wen-Xiu Liu Wei He Ning Qin Xiang-Zhen Kong Qi-Shuang He Hui-Ling Ouyang Fu-Liu Xu 《Environmental science and pollution research international》2013,20(4):2033-2045
The levels of organochlorine pesticides (OCPs) in the water, suspended solids, and sediments from Lake Chaohu during the high water level period were measured by a solid-phase extraction gas chromatograph–electron capture detector. The spatial distributions of the three phases and the water/suspended solids and sediment/water partition coefficients were analyzed. The results showed the following: (1) The mean contents of OCPs in the water, suspended solids, and sediments were 132.4?±?432.1 ng/L, 188.1?±?286.7 ng/g dry weight (dw), and 13.7?±?9.8 ng/g dw, respectively. The dominant OCP components were isodrin (85.1 %) for the water, DDTs (64.4 %) for the suspended solids, and both isodrin (48.5 %) and DDTs (31.8 %) for the sediments. (2) β-HCH was the primary isomer of HCHs in the water and sediments, and the proportions were 61.7 and 41.3 %; γ-HCH was the primary isomer in the suspended solids, accounting for 49.3 %; p,p′-DDT was the dominant content of DDTs in the water and suspended solids, whereas p,p′-DDD was the main metabolite of DDTs in the sediments. (3) The concentrations of contaminants in the water from the western lake were greater than those from the eastern lake, but the concentrations in the suspended solids from the western lake were less than those from the eastern lake. (4) There was no significant correlation between the water–suspended solids partition coefficient K d and the n-octanol–water partition coefficient K ow, and between the sediment–water organic-C weighted sorption coefficients K oc and K ow. 相似文献
17.
Oxidative co-treatment using hydrogen peroxide with anaerobic digestion of excess municipal sludge. 总被引:1,自引:0,他引:1
Jesus A Cacho Rivero Narain Madhavan Makram T Suidan Philippe Ginestet Jean-Marc Audic 《Water environment research》2006,78(7):691-700
The effect of an oxidative co-treatment on anaerobic digestion of a mixture of primary and waste activated sludge was investigated. The oxidant used in this study was hydrogen peroxide (H2O2). A maximum improvement in solid destruction of 15.2% was achieved in the overall process, with a dosage of 2.0 g H2O2/g influent volatile suspended solids (VSS(influent)). All configurations operated at this dosage also showed statistically significant increases in solids removal. A statistically significant enhancement in overall solids destruction was observed for the lower oxidant dosage (0.5 H2O2/g VSS(influent)). Surprisingly, for 1.0 g H2O2/g VSS(influent), only one of the three configurations involving oxidative co-treatment showed significant increases in solids destruction. Special attention was paid to the performance of this process relative to fecal coliforms destruction. Class A biosolids were obtained for all the different hydrogen peroxide dosages used when oxidative co-treatment is combined with a two-stage anaerobic digestion process. 相似文献
18.
Valente GF Santos Mendonça RC Pereira JA Felix LB 《Journal of environmental science and health. Part. B》2012,47(4):355-361
Iron electrodes were used for electrocoagulation (EC) treatment of wastewater from a dairy plant. Electrolysis time, pH, current density and distance between electrodes were considered to assess the removal efficiency of chemical oxygen demand (COD), total solids (TS) and their fractions and turbidity. Samples were collected from the effluent of a dairy plant using a sampling methodology proportional to the flow. The treatments were applied according to design factorial of half fraction with two levels of treatments and three repetitions at the central point. The optimization of parameters for treating dairy industry effluent by electrocoagulation using iron electrodes showed that electric current application for 15 minutes, an initial sample pH close to neutral (pH 7.0) and a current density of 50 A (.)(m-2) resulted in a significant reduction in COD by 58 %; removal of turbidity, suspended solids and volatile suspended solids by 95 %; and a final treated effluent pH of approximately 9.5. Negative consequences of the type of electrode used were the emergence of an undesirable color and an increase in the proportion of dissolved solids in the treated effluent. 相似文献
19.
This study investigates the effect of dispersed microorganisms and exocellular polymeric substances on biomass dewaterability. Specific resistance to filtration (SRF) was measured for biomass from a membrane bioreactor and a completely mixed activated sludge system. Both laboratory-scale reactors were fed with synthetic wastewater and operated at a high food-to-microorganism ratio (F/M) (1 to 11 kilograms chemical oxygen demand per kilogram mixed liquor volatile suspended solids per day [kgCOD/(kg MLVSS.d)]) and short solids retention times (0.25 to 5 d). The SRF values were affected by strong interactions of three parameters: (1) the mixed liquor suspended solids concentration, (2) the amount of dispersed microorganisms, and (3) the exocellular polymeric substances (EPS) concentration. At F/M smaller than 2 kg COD/(kg MLSS.d) and mixed liquor suspended solids (MLSS) concentration higher than 2000 mg/L, increasing amount of dispersed microorganisms in the biomass yielded higher SRF values. However, at high F/M (> 5 kg COD/kg MLSS.d) and low MLSS concentrations (< 600 mg/L), lower EPS concentrations resulted in slightly smaller SRF values, even though the amount of dispersed microorganisms in the biomass was much higher. Thus, at low MLSS concentrations, EPS concentrations rather than the amount of dispersed microorganisms tend to control SRF. 相似文献