植物与微生物联合修复垃圾渗滤液污染土壤

发布时间：2018-01-04 07:19

本文关键词：植物与微生物联合修复垃圾渗滤液污染土壤　出处：《重庆大学》2015年硕士论文　论文类型：学位论文

【摘要】：长期以来,国内一些老垃圾填埋场由于防渗措施较差、渗滤液处理系统不完善,导致渗滤液污染填埋场周边农田的情况日益严重。利用植物与微生物联合作用对污染土壤进行原位修复是一种较为理想的修复策略,已成为当前该领域研究的热点。本研究针对重庆市某受渗滤液污染农田土壤中Cd、Pb超标,有机污染物含量较高,属于重金属-有机物复合污染土壤的特性,筛选出广东万年青(Aglaonema modestum)、白掌(Spathiphyllum kochii)和孔雀竹芋(Calathea makoyana)作为修复植物,考察了植物在污染土壤中的生物量、植物体内重金属积累量以及污染土壤的修复效果。并以广东万年青作为参试植物,以驯化活性污泥作为接种微生物进行联合修复的研究。得出以下主要结论:①广东万年青在污染土壤中生长良好,对污染物具有较强的耐性。白掌和孔雀竹芋在污染土壤中受到一定毒害作用,但生物量基本保持不变。广东万年青、白掌和孔雀竹芋对Cd的富集系数分别为1.19、0.92和0.60,对Pb的富集系数分别为0.97、0.72和0.72,可看出广东万年青相比另外两种植物具有更强的重金属富集能力。广东万年青对Cd和有机物的去除效果优于白掌和孔雀竹芋,而对Pb的去除能力与孔雀竹芋相当。②添加活性污泥能明显提高对污染土壤中有机物的降解,同时能降低Cd和Pb的生物有效性。随着活性污泥添加量的增加,土壤修复效率显著提高,其中当添加20%的水分(m/m)、氮磷比3:1的营养元素(质量比)、10mg/kg的表面活性剂SDS、10%的电子受体H2O2(m/m)时,活性污泥对有机物的降解效率最高;当添加10%的水分(m/m)、氮磷比3:1的营养元素(质量比)、10mg/kg的SDS和5%的H2O2(m/m)时,活性污泥对Cd的固定效果最好;当添加10%的水分(m/m)、10mg/kg的SDS、15%的H2O2(m/m)时,活性污泥对Pb的固定效果最好,但任何氮磷比的营养元素都会提高Pb的迁移性。③植物和微生物联合修复时,活性污泥能促进广东万年青的生长,植物生物量明显提高。添加活性污泥会降低植物地上部Cd的含量,但可以提高根部Cd的含量;植物地上部和根部Pb的含量均有所降低。虽然添加活性污泥在一定程度上降低了广东万年青对Cd和Pb的转移和富集能力,但活性污泥能够促进植物生长,使植物地下部和根部生物量显著提高,从而对土壤Cd和Pb的提取总量大幅度增加,有效降低了土壤重金属含量。同时,添加活性污泥后,土壤中土著微生物难以降解的有机物也得到有效的去除,土壤有机物降解率也显著提升。因此,采用合适的植物与微生物联合修复能提高对渗滤液污染土壤的修复效率,具有一定的应用潜力。
[Abstract]:For a long time, some domestic old landfill due to poor anti-seepage measures, leachate treatment system is not perfect, resulting in landfill leachate pollution surrounding farmland is becoming increasingly serious. The combined effect of plants and microorganisms in situ remediation of contaminated soil is an ideal repair strategy, has become a hot research in the field. In this study, Chongqing city by the leachate pollution in farmland soil Cd and Pb exceed the standard, higher levels of organic pollutants, belong to the characteristics of heavy metal and organic contamination of soil, screened Guangdong evergreen (Aglaonema Modestum), whitehand (Spathiphyllum kochii) and Calathea makoyana (Calathea makoyana) as repair plants, effects of biomass plants in contaminated soil, the accumulation and the remediation effect of heavy metals in plants. Taking Guangdong evergreen as tested plants, domesticated Study on activated sludge as inoculating microorganism remediation. The main conclusions are as follows: 1. Guangdong evergreen in contaminated soil grew well and had a strong tolerance to pollutants. Patinii and Calathea makoyana by some toxic effects in the polluted soil, but the biomass remained unchanged. Guangdong evergreen, white peacock and enrichment coefficient arrowroot of Cd 1.19,0.92 and 0.60 respectively, the enrichment coefficient of Pb were 0.97,0.72 and 0.72, can be seen in Guangdong wanniangqing compared to the other two kinds of heavy metals in plants have stronger enrichment ability. Guangdong wanniangqing on Cd and the organic removal effect is better than the White Peacock and arrowroot, and ability to remove Pb and the peacock arrowroot is. The addition of activated sludge can improve the degradation of organic pollutants in the soil, and can reduce the bioavailability of Cd and Pb. With the increase of amount of activated sludge, Soil remediation efficiency is enhanced, which when added 20% water (m/m), ratio of nitrogen and phosphorus nutrient 3:1 (mass ratio), 10mg/kg surfactant SDS, 10% H2O2 electron acceptor (m/m), activated sludge on organic matter degradation rate is highest; when adding 10% water (m/m). The ratio of nitrogen to phosphorus nutrient 3:1 (mass ratio), 10mg/kg SDS and 5% H2O2 (m/m), the best fixation effect on activated sludge Cd; when adding 10% water (m/m), 10mg/kg SDS, 15% H2O2 (m/m), the best fixation effect of activated sludge on Pb, but any nutrients nitrogen and phosphorus ratio will increase the mobility of Pb. The plant and microbial remediation, activated sludge can promote the growth of Guangdong evergreen, plant biomass significantly increased. Addition of activated sludge will reduce the content of plant shoot Cd, but can increase the content of Cd in roots and shoots; content of plant the roots of Pb have Although the addition of activated sludge decreased. Lower Guangdong wanniangqing on Cd and Pb transfer and accumulation ability to a certain extent, but the activated sludge can promote plant growth, plant root and root biomass was significantly increased, and the total extraction greatly on soil Cd and Pb increased, effectively reducing the heavy metal content in soil. At the same time, addition of activated sludge, soil organic matter in indigenous microorganisms is difficult to be degraded effectively the removal of soil organic matter degradation rate was also significantly improved. Therefore, the appropriate plant and microbial remediation can improve the repair efficiency of Leachate Contaminated Soil, has great potential application.

【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X53;X17

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