氧化技术处理垃圾渗滤液研究进展

城市垃圾渗滤液是一种成分复杂、有机物、氨氮浓度高的难处理废水。针对垃圾渗滤液有机物的难去除性,许多国家开始采用氧化技术来对垃圾渗滤液进行直接处理或深度处理。论文在阐述氧化处理技术的分类和原理的基础上,分析总结了国内外各种氧化技术在垃圾渗滤液处理中的应用,并提出了当前应用氧化技术处理垃圾渗滤液所存在的问题和发展方向。     

老龄垃圾渗滤液处理技术研究进展

垃圾在长期填埋过程中产生的老龄垃圾渗滤液成分复杂,处理更为困难。老龄垃圾渗滤液具有氨氮含量高、C/N低、可生化性差等特点。从物化处理、生化处理和生物脱氮等方面对国内外该类渗滤液的处理工艺进行了分析,指出了各种处理方法的优势与不足,并在此基础上对老龄垃圾渗滤液处理技术的发展进行了展望。     

吹脱法去除垃圾渗滤液中氨氮的技术进展

介绍了吹脱法在垃圾渗滤液氨氮脱除方面的研究进展,着重对渗滤液氨氮吹脱的关键因素、联合技术和工程应用进行了总结和分析,并对今后垃圾渗滤液氨氮吹脱技术的研究提出了建议。     

改性粉煤灰处理垃圾渗滤液中氨氮的研究

采用溶胶-凝胶法对粉煤灰进行改性,并在500℃条件下煅烧以去除残留的有机物质。研究改性粉煤灰处理淮南市垃圾渗滤液中氨氮去除效果,从而为垃圾渗滤液中氨氮的去除提供一个有效途径。通过垃圾渗滤液吸附实验,研究表明:在p H接近中性,粉煤灰投加量为3.0 g/L,垃圾渗滤液在低浓度下氨氮去除率接近100%;垃圾渗滤液初始氨氮浓度为16 mg/L时,垃圾渗滤液中氨氮去除率为80.24%。改性后的粉煤灰的吸附性能更好。     

垃圾渗滤液脱氮技术研究现状

垃圾填埋场渗滤液(尤其是"中老年"填埋场渗滤液)中较高浓度的氨氮含量是导致其处理难度较大的一个重要原因,对其进行脱氮处理是后续生物处理正常运行的重要保证。综述了当今常用的氨氮去除方法,如氨吹脱、化学沉淀、湿式催化氧化、生物法等,分析讨论了各处理技术的原理及其在垃圾渗滤液脱氮中的应用。     

老龄化垃圾渗滤液处理技术研究进展

垃圾渗滤液的浸出,对地表水和地下水的水质具有潜在威胁。渗滤液经过5年的填埋期后会逐渐发生老化,老龄化垃圾渗滤液中含有高浓度的难降解有机物、氨氮、重金属和无机盐,常规污水处理方法难以对其进行有效处理。目前针对老龄化垃圾渗滤液水质的特殊性,衍生出了一系列处理工艺：膜分离工艺、高级氧化工艺以及以厌氧氨氧化作为核心工艺的生物处理技术等。本文系统研究了老龄化垃圾渗滤液处理技术的国内外研究进展,探讨了不同技术工艺的优缺点,并指出改进的建议和发展方向。     

化学氧化法处理工业垃圾渗滤液中氨氮的研究

采用化学氧化法对工业垃圾渗滤液中氨氮进行处理.通过二氯异氰尿酸钠、次氯酸钠、次氯酸钙、高铁酸钾、过硫酸钾五种氧化剂对工业垃圾渗滤液中氨氮的处理结果对比,得出次氯酸钠对氨氮的处理效果更为显著.最佳反应条件为:反应温度30℃、搅拌强度300 r/min、次氯酸钠加入量3.93 g/L、反应时间1h,工业垃圾渗滤液中氨氮含量...     

纳滤技术在垃圾渗滤液深度处理中的应用

采用纳滤技术对垃圾焚烧场渗滤液进行深度处理,探讨了该方法用于垃圾渗滤液深度处理的可行性.实验结果表明,COD去除率为80％～93％,氨氮去除率为45％～70％.实验过程中膜通量和脱盐率变化不大,膜性能稳定,可为垃圾渗滤液处理提供参考.     

以A/O+MBR为核心的渗滤液处理厂工艺调试运行

以常州某家垃圾渗滤液处理厂为例,验证A/O+MBR生化处理"成熟期"填埋场中渗滤液的可行性,此渗滤液具有氨氮高、可生化性低等特点。生物工艺与物化处理相结合的对渗滤液处理的效果起到关键的作用,以溧阳某垃圾渗滤液处理厂为例,对垃圾渗滤液处理工程中生物处理的调试运行进行介绍。调试证明,A/O+MBR+RO的工艺组合处理高氨氮低COD的渗滤液是可行的。     

Fenton+氨吹脱+EGSB+AO池+沉淀池组合工艺处理垃圾渗滤液研究

针对填埋场垃圾渗滤液COD_(Cr)、氨氮浓度高等特点,采用Fenton+氨吹脱+EGSB+AO池+沉淀池组合工艺处理填埋场垃圾渗滤液。研究了Fenton、氨吹脱处理垃圾渗滤液的最佳反应条件以及组合工艺处理效果。结果表明,经组合工艺处理后出水COD_(Cr)及氨氮平均浓度分别为385mg/L、40mg/L,出水水质能满足《污水排入城镇下水道水质标准》（GB/T31962-2015）中A级标准,为垃圾渗滤液处理提供技术参考。     

Sequential anaerobic–aerobic treatment of sulphur rich phenolic leachates

Sequential biological anaerobic–aerobic treatment of oil shale ash dump leachate was studied using laboratory-scale reactors and bioassays. The COD of the leachate was 2·0–3·0 g dm^?3. The leachate was known to contain several phenolic compounds and to have a high sulphur concentration. The proportion of the leachate in the feed of the biological process was gradually increased during a 309 day test period. With 100% leachate in the feed, COD removal was 35% in the anaerobic stage while in the combined process the COD and BOD₇ removals were up to 75% and 99%, respectively. The removal of total phenols was insignificant in the anaerobic stage, while up to 85% removal was obtained by the combined anaerobic–aerobic process. In the anaerobic stage, degradation of organic compounds was mainly a result of sulphide production. The results demonstrated that the leachates were amenable to biological treatment.     

填料对生活垃圾降解及渗滤液水质水量的影响

为了考察在生活垃圾中添加具有吸附性和干燥性的填料对垃圾降解速率、渗滤液产生量、渗滤液水质的影响,在实验室建立了五个圆柱形垃圾厌氧填埋反应器,用于模拟垃圾填埋场的运行情况,以不添加填料反应器作对比,其余四个反应器中分别混合加入锯末、活性炭、沸石、报纸作为填料。实验中对五个反应器中的垃圾层高度、渗滤液产生量、产生渗滤液的COD和NH3-N及重金属离子浓度进行了检测。实验结果表明:在垃圾中添加具有吸附和干燥性的填料具有减少渗滤液产量、加速垃圾降解和减少溶入渗滤液中污染物质的作用,整体来看,锯末在发挥这些作用方面要好于其他三种填料。     

蒸发气相吸收耦合方法处理垃圾渗滤液

对垃圾渗滤液蒸发、蒸发-气相酸吸收、蒸发-气相碱吸收和蒸发-气相酸吸收-气相碱吸收处理进行了试验研究,考察了不同工艺真空度和渗滤液初始pH对冷凝液水质的影响。结果表明：采用蒸发法时,随着真空度的升高,冷凝液pH、NH₃-N浓度和总含盐量（TDS）值均呈下降趋势,而COD浓度逐渐增加。当初始渗滤液呈酸性时,冷凝液中NH₃-N的含量较低,而COD的含量较高;当初始渗滤液呈碱性时,冷凝液中COD的含量较低,而NH₃-N的含量较高。采用蒸发-气相酸吸收法可有效降低渗滤液中NH₃-N的含量,采用蒸发-碱吸收法可去除渗滤液中的COD。采用蒸发-气相酸吸收-气相碱吸收法能同时降低渗滤液中COD、NH₃-N和TDS的浓度,在渗滤液初始pH为8.1的条件下,对渗滤液中COD、NH₃-N和TDS的去除率均达99%以上,浓度分别降至60mg/L、8mg/L和10mg/L以下,冷凝液水质符合GB 16889—2008对环境敏感地区的排放标准。     

The effects of nitrate and nitrate‐supplemented leachate addition on methanogenesis from Municipal Solid Waste

The recirculation of nitrified leachate through landfill sites, followed by in situ denitrification, represents a novel and more sustainable approach for the removal of ammonia from leachate, prior to discharge. The effects of nitrate and leachate supplementation on methanogenesis in Municipal Solid Waste (MSW) were studied in batch cultures. The addition of a range of nitrate concentrations to MSW samples had an inhibitory effect on methanogenesis. The effects were dose‐dependent, such that recovery of methane production was recorded within 5 and 23 days with added 100 and 750 mg NO₃ dm^?3, respectively. Even after 24 days, no recovery was observed in cultures challenged with 1000 mg NO₃ dm^?3. The enumeration of denitrifying bacteria in a range of fresh, actively methanogenic and aged, well‐decomposed MSW confirmed the potential of MSW for rapid denitrification. Methanogenesis was not inhibited by the addition of leachate (20–100% strength) that contained high concentrations of VFAs. However, when the same leachate was supplemented with nitrate (250 mg NO₃ dm^?3), methanogenesis was inhibited by the addition of leachate concentrations ≥20%, which was attributed to inhibition of denitrification by VFAs. Propionate accumulated, confirming the importance of methanogenesis as an electron sink. With the removal of nitrate and the recovery of methanogenesis, net propionate concentrations decreased. Copyright © 2004 Society of Chemical Industry     

移动床生物膜法处理垃圾渗滤液COD降解动力学

采用移动床生物膜反应器间歇处理城市垃圾渗滤液,并建立了其COD降解的动力学模型。试验结果表明,模型能够很好地描述渗滤液COD的好氧降解过程,其中动力学参数K2可用来指示基质的降解速率, Sn可用作渗滤液可生化性和可降解程度的评价指标。在不同底物浓度下模拟出的参数K2和Sn均与底物浓度S0呈线性关系。在不同填料填充比下的拟合结果表明动力学参数K2与生物量浓度无关。两级MBBR串联运行能够有效处理该垃圾渗滤液,当总HRT为4 d,平均COD去除率达89.24％,其出水COD平均为452.10 mg·L-1,与模型得出该进水浓度下含有的惰性COD相近,直接证明了模型对评价该渗滤液可生化性具有较高的可靠性。     

垃圾渗滤液生化出水絮凝-纳滤处理及过程机理

垃圾焚烧发电厂渗滤液是一种含高浓度腐殖酸类物质和高盐含量的复杂有机废水, 传统生化处理后仍难达标排放。本工作围绕垃圾渗滤液生化出水的特性, 开展了Ca(OH)₂絮凝、臭氧氧化预处理与NF处理相结合的处理工艺, 并对处理过程的机理进行了探讨。研究表明, 渗滤液生化出水经过Ca(OH)₂絮凝处理, 可以有效地去除其中的杂环类化合物。生化出水经8 g·L^-1的Ca(OH)₂絮凝处理后, 比MBR出水产水通量提高达8.2%。对Ca(OH)₂絮凝出水进行臭氧氧化处理, 虽然降低了它的COD, 但并未进一步提高其NF膜通量, 其主要原因可能是臭氧氧化生成的硅氧烷类物质造成了膜的污染;与RO处理垃圾渗滤液生化出水相比较, NF膜无法分离废水中的酮类、胺和酰胺类、杂环类化合物, 使得NF产水的COD处在100~160 mg·L^-1。NF平均膜通量的增大可导致产水COD略有上升;垃圾渗滤液生化出水及其预处理水在NF处理过程中, 都没有表现出严重的膜污染。     

Allelopathic Exudates of Cogongrass (Imperata cylindrica): Implications for the Performance of Native Pine Savanna Plant Species in the Southeastern US

We conducted a greenhouse study to assess the effects of cogongrass (Imperata cylindrica) rhizochemicals on a suite of plants native to southeastern US pine savanna ecosystems. Our results indicated a possible allelopathic effect, although it varied by species. A ruderal grass (Andropogon arctatus) and ericaceous shrub (Lyonia ferruginea) were unaffected by irrigation with cogongrass soil “leachate” (relative to leachate from mixed native species), while a mid-successional grass (Aristida stricta Michx. var. beyrichiana) and tree (Pinus elliottii) were negatively affected. For A. stricta, we observed a 35.7 % reduction in aboveground biomass, a 21.9 % reduction in total root length, a 24.6 % reduction in specific root length and a 23.5 % reduction in total mycorrhizal root length, relative to the native leachate treatment. For P. elliottii, there was a 19.5 % reduction in percent mycorrhizal colonization and a 20.1 % reduction in total mycorrhizal root length. Comparisons with a DI water control in year two support the possibility that the treatment effects were due to the negative effects of cogongrass leachate, rather than a facilitative effect from the mixed natives. Chemical analyses identified 12 putative allelopathic compounds (mostly phenolics) in cogongrass leachate. The concentrations of most compounds were significantly lower, if they were present at all, in the native leachate. One compound was an alkaloid with a speculated structure of hexadecahydro-1-azachrysen-8-yl ester (C₂₃H₃₃NO₄). This compound was not found in the native leachate. We hypothesize that the observed treatment effects may be attributable, at least partially, to these qualitative and quantitative differences in leachate chemistry.     

电催化氧化技术提高垃圾渗滤液可生化性的研究

本文引入了TbOD(总BOD)概念代替BOD,来作为渗滤液可生化性指标的一个间接量度,其主要目标是考察经电催化氧化技术对垃圾渗滤液进行预处理后,水质可生化性的变化情况．结果表明,电解时间以及电流密度对渗滤液可生化性的影响较为明显,电催化氧化技术能有效提高渗滤液水质的可生化性,TbOD／COD由原来的0．39上升到0.75,电催化氧化对NH3-N的去除效果明显,电解90min后,最终NH3-N去除率能够达到94．8％,有利于后续的生物法处理。     

Phenol and refuse catabolism: The effects of different co-disposal strategies

The efficacies of different co-disposal strategies (elution, leachate recycle, single addition (batch), single addition plus rain permeation) to treat phenol (1000 and 2000 mg dm⁻³) were investigated with laboratory microcosms. The elution columns recorded the highest total removals but were coincident with low leachate pH values and high residual phenol concentrations. In contrast, leachate recycle facilitated both increased leachate pH values and methane evolution. Rain permeation proved detrimental to phenol attenuation since the molecule was rapidly displaced together with key methanogenic precursors. All the microcosms were characterised by protracted lag phases prior to phenol catabolism and the nitrate- and sulphate-reducing bacteria were particularly sensitive to the added molecule. © 1998 Society of Chemical Industry     

Influence of Liquid Height to the Oxidation Process of Landfill Leachate by Using Ozone

The influence of liquid height on chemical oxygen demand (COD) of leachate was investigated. When 400 mL leachate was filled in a thick tube reactor (TTR) with height of 0.063 m, COD removal efficiency was 45.69%, while ozone dosage was 3.35 mg_O3/mg_COD. As leachate was filled in a slender tube reactor (STR) with a height of 0.815 m, removal efficiency was 51.81%, and ozone dosage was 3.12 mg_O3/mg_COD. The results indicated that COD removal efficiency increased with the height of liquid. It is believed that the liquid height increased hydraulic pressure and resulted in COD removal efficiency.