汲取液对正渗透微生物燃料电池处理垃圾渗滤液的影响

以垃圾渗滤液为阳极液,系统研究了汲取液种类和浓度对正渗透微生物燃料电池(OsMFC)工艺处理垃圾渗滤液性能的影响.结果表明,在汲取液为氯化钠的情况下,OsMFC工艺的最大功率密度可达0.44 W·m~(-2),表观内阻为236.75Ω,水通量为0.98 L·m~(-2)·h~(-1),TOC、NH_4~+-N、TN和TP的去除率分别达到89.51%、93.27%、94.01%和96.95%,均好于碳酸氢钠和碳酸氢铵作为汲取液时的处理效果.此外,氯化钠汲取液浓度越大,产电性能越好,表观内阻越小,水通量越大.产电性能随汲取液浓度的增大变化不大,在汲取液浓度为1 mol·L~(-1)的情况下,水通量和盐返混量的比值最大,处理效果最好.     

Landfill leachate treatment in assisted landfill bioreactor

Landfill is the major disposal route of municipal solid waste（MSW） in most Asian countries. Leachate from landfill presents a strong wastewater that needs intensive treatment before discharge. Direct recycling was proposed as an effective alternative for leachate treatment by taking the landfill as a bioreactor. This process was proved not only considerably reducing the pollution potential of leachate, but also enhancing organic degradation in the landfill. However, as this paper shows, although direct leachate recycling was effective in landfilled MSW with low food waste fraction （3.5%, w/w）, it failed in MSW containing 54% food waste, as normally noted in Asian countries. The initial acid stuck would inhibit methanogenesis to build up, hence strong leachate was yielded from landfill to threaten the quality of receiving water body. We demonstrated the feasibility to use an assisted bioreactor landfill, with a well-decomposed refuse layer as ex-situ anaerobic digester to reducing COD loading in leachate. By doing so, the refuse in simulated landfill column （2.3 m high） could be stabilized in 30 weeks while the COD in leachate reduced by 95%（61000 mg/L to 3000 mg/L）. Meanwhile, the biogas production was considerably enhanced, signaling by the much greater amount and much higher methane content in the biogas.     

Evolution on qualities of leachate and landfill gas in the semi-aerobic landfill

To study the characteristics of stabilization in semi-aerobic landfill, large-scale simulated landfill was constructed based on the semiaerobic landfill theory. Consequently, the concentrations of chemical oxygen demand (COD), ammonia nitrogen, and nitrite nitrogen, and the pH value in leachate, as well as the component contents of landfill gas composition (methane, carbon dioxide, and oxygen) in landfill were regularly monitored for 52 weeks. The results showed that COD and ammonia concentrations declined rapidly and did not show the accumulating rule like anaerobic landfill, and remained at about 300 and 100 mg/L, respectively, after 48 weeks. Meanwhile, the descending rate reached 98.9% and 96.9%, respectively. Nitrate concentration increased rapidly after 24 weeks and fluctuated between 220–280 mg/L after 43 weeks. The pH values were below 7 during the first 8 weeks and after that leachates appeared to be alkaline. Carbon dioxide was the main composition in landfill gas and its concentration remained at a high level through the whole stabilization process. The average contents of carbon dioxide, oxygen, and methane varied between 19 vol.%–28 vol.%, 2 vol.%–8 vol.%, and 5 vol.%–13 vol.%, respectively. A relative equilibrium was reached after 48 weeks. The highest temperature in the landfill chamber could amount to 75.8 degrees centigrade.     

铁离子循环电解法处理垃圾填埋场晚期渗滤液

使用箱式电化学反应器,采用铁离子循环电解工艺处理垃圾填埋场晚期渗滤液,确定了硫酸铁的剂量,考察了该工艺去除污染物的效率与主要因子对污染物去除的影响.实验结果表明,铁离子循环电解工艺对垃圾填埋场晚期渗滤液具有良好的处理效果,在电压3.80V、pH值为3.0、电解时间40min条件下,电解后的渗滤液满足二级排放标准的要求;硫酸铁的合理浓度为1000mg·L-1;电解电压不宜超过4.0V,电解时间不宜超过40min;渗滤液中氯离子的浓度对COD和NH 4-N的去除有显著影响,浓度越高COD和NH 4-N去除效果越好,且其对NH 4-N去除的影响大于对COD去除的影响.     

膜生物反应器在垃圾渗滤液处理工程中的应用研究

介绍膜生物反应器的基本原理、优点、类型和影响因素,总结膜生物反应器在垃圾渗滤液处理工程中的应用现状及进展。工程应用实践表明,膜生物反应器固液分离效果好、污泥负荷高、可截留大分子难降解有机物、剩余污泥产量低、占地面积小、易于实现自动化,在垃圾渗滤液处理领域具有很好的应用前景。根据工程实际经验,针对膜生物反应器在渗滤液处理工程中的应用,提出工程设计和运行控制方面的建议。     

膜生物反应器处理晚期垃圾渗滤液亚硝化性能及其抑制动力学分析

采用连续流MBR反应器处理晚期垃圾渗滤液,考察其亚硝化性能;并探讨底物、产物和毒性物质对亚硝化性能的抑制及其动力学特性.结果表明,在进水NH₄⁺-N浓度为(280±20) mg/L时,通过控制DO为0.5~1 mg/L,pH值为7.8~8.2和温度为(30±1)℃,成功启动MBR的亚硝化工艺,在第32d时, NO₂^--N积累率为84.27%;后逐步升高进水负荷,并提高DO至2~3 mg/L,逐渐实现MBR系统中以晚期垃圾渗滤液原液为进水的亚硝化,在第112d时,系统出水NO₂^--N浓度为889 mg/L, NO₂^--N积累率为97.23%.底物、产物和毒性物质的抑制实验表明,毒性物质对微生物的抑制作用强于底物和产物;当毒性物质浓度(以COD计)为1600.2 mg/L时,氨氧化速率下降了22.15%,而相应条件下若以FA为单因子抑制时,氨氧化速率下降了4.74%~6.49%,若以FNA为单因子抑制时,氨氧化速率相比下降了14.46%~15.86%.分别采用Haldane底物抑制模型、Aiba产物抑制模型以及修正后的毒性物质抑制模型对实验数据进行非线性拟合,相关系数R²分别为0.9821、0.9961和0.9924,并得到底物、产物和毒性物质的抑制动力学模型.     

垃圾渗滤液浓缩液高铁酸钾联合PAC处理技术研究

以碟管式反渗透(DTRO)处理垃圾渗滤液产生的浓缩液为研究对象,采用高铁酸钾联合聚合氯化铝(PAC)处理浓缩液.结果表明,在单独采用高铁酸钾的条件下,DTRO浓缩液COD、UV_(254)和色度去除率随着高铁酸钾投加量的增加而升高.高铁酸钾投加量为10 g·L~(-1),pH为5时,COD、UV_(254)和色度去除效果最佳,反应在40 min内基本完成,COD、UV_(254)、色度去除率分别为38.5%、35.7%和68.5%.通过响应曲面法分析高铁酸钾联合PAC处理DTRO浓缩液效果可得,高铁酸钾投加量在10.0～13.0 g·L~(-1)之间,pH调节至3.0～4.0,PAC投加量为13.0～15.0 g·L~(-1)时,DTRO浓缩液COD去除率可达74%.     

电催化系统-电生物炭接触氧化床处理垃圾渗滤液

 提出了电催化系统(ECS)组合电生物炭接触氧化床(EBACOR)来处理垃圾渗滤液的方法.结果表明,ECS-EBACOR法诸多的影响因素中,对处理效率影响最大的是ECS的电活性催化填料组分.GC/MS分析结果表明,垃圾渗滤液中的64种有毒有机污染物经ECS处理后,大部分已被矿化成CO₂、H₂O或降解为小分子有机物.ECS-EBACOR现场运行试验结果还表明,当垃圾渗滤液废水中的COD和NH₃-N浓度分别在3000～5000mg/L以及1100～1780mg/L范围时,COD和NHs₃-N去除率均可超过90%.     

紫外催化过硫酸盐深度处理垃圾焚烧厂渗滤液

为研究垃圾焚烧厂渗滤液生化出水的处理特性,对比了单独紫外(UV)体系、单独过硫酸盐(PS)体系以及紫外/过硫酸盐(UV/PS)体系深度处理垃圾渗滤液效果,发现UV/PS体系对渗滤液中有机污染物的去除效果较另外两体系的效果优异,因此采用UV/PS体系处理典型难降解有机物腐殖酸并考察体系的处理效能.在初始腐殖酸浓度为200...     

Three-stage aged refuse biofilter for the treatment of landfill leachate

A field-scale aged refuse(AR) biofilter constructed in Shanghai Refuse Landfill,containing about 7000 m3 aged refuse inside,was evaluated for its performance in the treatment of landfill leachate. This AR biofilter can be divided into three stages and can manage 50 m3 landfill leachate per day. The physical,chemical,and biological characteristics of AR were analyzed for evaluating the AR biofilter as leachate treatment host. The results revealed that over 87.8%-96.2% of COD and 96.9%-99.4% of ammonia nitrog...     

Characteristics of dissolved organic matter （DOM） in leachate with different landfill ages

The main objective of the study was to investigate the characteristics of dissolved organic matter (DOM) in leachate with different landfill ages through the chemical, spectroscopic, and elemental analysis. Humic acid (HA), fulvic acid (FA), and hydrophilic (HyI) fractions were isolated and purified by the XAD-8 resin combined with the cation exchange resin method. The analytical results of fluorescence excitation-emission matrix spectroscopy (EEMs) revealed that the fluorescence peaks were protein-like fluorescence for young landfill leachate, while the fluorescence peaks for medium and old landfill leachate were humic-like and fulvic-like fluorescence, respectively. Elemental analysis showed that carbon, hydrogen, and nitrogen content decreased with landfill age, while the oxygen content increased. Moreover, the nitrogen content in these isolated fractions followed HA ＞ HyI ＞ FA. The results of elemental analysis, FT-IR, and fluorescence EEMs also confirmed that aromatic carbons and portions of aliphatic functional groups were more abundant in leachate samples with increasing landfill age.     

Advanced landfill leachate treatment using a two-stage UASB-SBR system at low temperature

A two-stage upflow anaerobic sludge blanket(UASB) and sequencing batch reactor(SBR) system was introduced to treat landfill leachate for advanced removal of COD and nitrogen at low temperature.In order to improve the total nitrogen(TN) removal efficiency and to reduce the COD requirement for denitrification,the raw leachate with recycled SBR nitrification supernatant was pumped into the first-stage UASB(UASB1) to achieve simultaneous denitrification and methanogenesis.The results showed that UASB1 played an important role in COD removal and UASB2 and SBR further enhanced the nutrient removal efficiency.When the organic loading rates of UASB1,UASB2 and SBR were 11.95,1.63 and 1.29 kg COD/(m3·day),respectively,the total COD removal efficiency of the whole system reached 96.7%.The SBR acted as the real undertaker for NH4+-N removal due to aerobic nitrification.The system obtained about 99.7% of NH4+-N removal efficiency at relatively low temperature(14.9-10.9°C).More than 98.3% TN was removed through complete denitrification in UASB1 and SBR.In addition,temperature had a significant effiect on the rates of nitrification and denitrification rather than the removal of TN and NH4+-N once the complete nitrification and denitrification were achieved.     

碳酸盐-硫酸盐矿物强化垃圾渗滤液厌氧处理研究

厌氧消化通常是垃圾渗滤液生物处理的首要环节,但处理效率不高.本研究尝试通过添加碳酸盐、硫酸盐等矿物来提高垃圾渗滤液的厌氧转化效率.研究共设置5组厌氧生物反应器,包括投加硬石膏、方解石、石膏、白云石的反应器及空白对照,考察添加矿物对垃圾渗滤液厌氧消化的影响.从实验结果可以看出,添加矿物的反应器中COD的去除率可以达到75%左右,而空白对照组去除率尚不足60%,添加矿物反应器甲烷产量显著高于对照.从反应器中的p H变化可以看出,矿物的添加可以提高溶液中的p H.研究结果表明,添加碳酸盐/硫酸盐矿物对垃圾渗滤液中的有机物厌氧消化过程具有重要的促进作用.     

白腐菌附着式生物膜反应器处理垃圾渗沥液技术研究

以煤渣为填料 ,在自制反应器内利用白腐菌生物膜对垃圾渗沥液生化出水进行深度处理 .实验结果表明 ,在停留时间为 97h、葡萄糖浓度为 2 0 0 0mg·L-1、氨氮浓度为 84mg·L-1左右时 ,白腐菌生物膜对渗沥液深度处理的效果最佳 .此外 ,将白腐菌生物膜反应器在上述条件下的处理效果与普通活性污泥SBR法进行比较 ,结果表明前者的处理效果要明显好于后者 .     

垃圾填埋场渗滤液对生态环境的污染影响及其治理

随着城市化进程的快速发展,生活垃圾产生量不断增加,垃圾填埋场产生的垃圾渗滤液给生态环境带来了一定程度的污染,因此城市生活垃圾安全处置已成为生态环境保护的重要内容,必须重视对垃圾渗滤液的处理。本文论述了城市生活垃圾填埋场渗滤液对生态环境造成的危害,并提出了防治对策。     

渗滤液循环对填埋气体产生量影响的实验研究

以上海市生活垃圾组成为依据,通过填埋模拟柱实验研究了不同渗滤液循环方式对新鲜垃圾填埋层填埋气体(LFG)产生的影响.渗滤液循环方式包括:原液循环、厌氧预处理后循环、好氧预处理后循环、原液与陈垃圾柱出水混合后循环.结果表明,原液循环抑制了甲烷化进程,产气速率小,产气期分散.渗滤液经适当预处理后循环均能改善LFG的各项气量指标,表现为产气速率显著提高、产气期集中(本实验条件下约1a);Qt(实际累积产气量)增加,Q有效 Qt值(甲烷浓度大于50%的填埋气体量与实际累积产气量的比值)大于0 80,Qt Qp值(实际累积产气量与计算总产气量的比值)大于0 4.但渗滤液经不同预处理后循环对LFG各项气量指标的优化效果不同,排序为厌氧预处理后循环>原液与陈垃圾柱出水混合后循环>好氧预处理后循环.优化LFG各项气量指标的关键是:①缩短填埋层进入稳定的甲烷化阶段的时间;②减少垃圾中有机物的场外去除量.而渗滤液的预处理程度和方式对这两个因素有直接影响.     

Fenton氧化法预处理并提高垃圾渗沥液可生化性的研究

采用Fenton氧化法对垃圾渗沥液进行预处理.基于响应面法研究了Fenton氧化法对垃圾渗沥液的处理效能,考察了初始pH值、H_2O_2投加量和[H_2O_2]/[Fe~(2+)]摩尔比对TOC去除率的影响,并拟合了TOC去除率与三因素之间的回归方程.同时,通过三维荧光和凝胶色谱比较了Fenton处理前后渗沥液的可生化性.结果发现,渗沥液中类富里酸等难降解有机物得到有效去除,B/C比从0.1左右升至0.25.研究表明,Fenton氧化法可有效改善垃圾渗沥液的可生化性,为后续生物处理创造了条件.     

自动控制实现两级混合床反应器处理垃圾渗滤液的短程硝化

采用两级混合床反应器(分别命名为 Hybrid Ⅰ和 HybridⅡ).对垃圾渗滤液中的COD和氨氮去除进行了试验研究,混合床由颗粒悬浮载体和固定组合软性填料相结合.试验以反应器的 DO、pH、ORP、SS等作为在线控制参数,研究了该反应器在固定温度(28～33℃)、不同进水负荷、DO 和 pH值下的运行效果,最后在 Hybrid 反应器的优化控制条件(DOHrbrid Ⅰ=(2.0±0.2)mg·L-1,DOHbrid Ⅱ=(1.5±0.2)mg·L-1,pHHybrid Ⅰ=8.0±0.2,pHHybrid Ⅱ=8.5±0.2,周期进水量为50L)下,实现了COD的高效去除以及氨氮的短程硝化去除.垃圾渗滤液进水 COD和氨氮分别为2300～5700mg·L-1和580～1150mg·L-1.两级混合床反应器工艺的COD和氨氮的去除率分别为93%和95%左右,总氮(TN)的去除率在82%以上.连续运行过程中 Hybrid Ⅰ和 Hybrid Ⅱ反应器的COD最大去除速率分别为 1.91 kg·m-3·d-1和0.75kg·m-3·d-1,氨氮亚硝化速率最大分别为 0.54kg·m-3·d-1和0.33kg·m-3·d-1.运行结果表明,该工艺耐冲击负荷强,处理效果稳定.     

UASB-A/O工艺处理垃圾渗滤液短程生物脱氮的实现

应用缺氧/厌氧UASB-A/O组合工艺处理高氮晚期渗滤液,在获得稳定有机物和氮同步去除的前提下,考察了如何实现并维持A/O系统内稳定短程硝化的途径.结果表明:在单一UASB反应器内,同时发生了缺氧反硝化和厌氧产甲烷的反应,有机物和NOx--N去除速率分别为5.3,1.1kg/(m3×d).12~30.6℃时,经过54d的运行, A/O反应器实现短程硝化 (亚硝态氮积累率>50%),此后亚硝态氮积累率迅速上升,70d后,亚硝态氮积累率稳定在90%以上.在A/O反应器内,游离氨和游离亚硝酸协同作用是实现并维持稳定短程硝化的决定因素.此外,以pH值作为A/O硝化反应进行的过程控制参数,可准确把握硝化终点,避免过度曝气破坏短程硝化,为氨氧化菌的生长创造有利条件,有效抑制亚硝酸盐氧化菌的生长并逐渐从系统中淘洗出去,实现了硝化菌种群的优化,荧光原位杂交技术检测也证明这一点.     

超临界水氧化处理垃圾渗滤液的响应面法优化

在间歇式反应釜上采用超临界水氧化法处理垃圾渗滤液.运用中心组合设计研究了反应温度（400~500 ℃）、压力（24~28 MPa）、反应时间（5~10 min）和氧化系数（1.5~2.5）,以及它们的交互作用对COD、氨氮去除率的影响,同时通过响应面法分析拟合出COD、氨氮去除率的二次回归方程,得到最优工艺条件.结果表明,各因素对COD去除率的影响主次作用排序为：反应压力>温度>氧化系数>反应时间;各因素对氨氮去除率的影响主次作用排序为：反应温度>压力>氧化系数>反应时间,而影响因素之间的交互作用对两者去除效果的影响却不明显.所得拟合方程对COD、氨氮去除率的预测误差分别小于±4%、±9%.拟合方程所得最佳实验条件为：时间5 min、温度496.05 ℃、压力27.69 MPa、氧化系数2.44,此时COD的去除率可以达到98.31%、氨氮去除率可以达到95.69%.