【作者】 刘苓；

【导师】 刘晓艳；

【作者基本信息】 大庆石油学院 ， 地球化学， 2010， 硕士

【摘要】 土壤是人类赖以生存和发展的物质基础和环境条件。石油进入土壤后,在复杂的土壤结构中经历着一系列物理、化学和生物过程,同时在重力和毛细力作用下不断入渗进入地下水而使其污染范围进一步扩大。进而直接或间接的危害到动植物和人类的生命健康,因此,研究大庆地区土-水系统中石油类污染物在自然条件下的迁移转化规律以及植物-微生物联合修复实验研究对油气田开发建设中土壤及水体环境的保护具有重要的现实意义。本文研究了大庆地区自然条件下石油类污染物在土-水系统中迁移转化规律;用生物泥浆法对影响本源微生物生物活性的因素进行测定,从而确定最佳的能应用于本源微生物生物强化的具体措施;在此基础上,再经实地考查及大量相关文献的阅读,优选出适宜的植物种子并将其按照一定的规律栽种于经过生物强化处理的土壤中,从而研究植物-微生物联合作用与石油污染降解率的关系。1.自然条件下石油类污染物在土-水系统中迁移转化规律根据实验目的,选取油井周围作为石油污染土壤的采样地点,观察在自然条件下石油类污染物的迁移转化特征。研究表明,石油类污染物含量总体上随深度的增加而降低,随距离的增加而减少,只有少数亲水性污染物在淋滤作用下向深处迁移。基于大庆地区的实际情况石油类污染物通常不会对本地区地下水层造成污染。2.影响本源微生物激活因素研究通过在实验室内模拟实验研究各种影响微生物生物活性的因素,确定本源微生物生物强化的具体方法。研究表明,温度对微生物生物活性的影响很大,最佳温度是40℃;引进外来碳源对微生物的生物活性的影响也很大,不同碳源在提高微生物活性能力方面存在差异,实验得出当淀粉加入量为C 0.5g/kg或葡萄糖加入量为C 0.1g/kg时最佳;含水率对微生物的影响较次要,最佳含水率为50%,太高会抑制微生物生物活性;适宜浓度的营养物质也会影响微生物活性,当营养物(N/P)的配比为10:1时微生物活性最大;试验得出,电子受体H2O2量累积14ml或表面活性剂浓度低于50mg/L时对微生物的繁殖才有利,但考虑到实际操作以及对环境方面的影响,不主张采用后两种方法。3.植物-微生物联合修复研究以前期实验为基础,选取三种植物种:黄豆、苜蓿和羊草,按照一定规律种植于经过处理的样品中。研究表明,前期经过处理的样品生物活性得到加强,与植物一起进行联合修复的作用明显;经过加入淀粉处理,种植黄豆-苜蓿组降解效果最好,黄豆组次之;总体看来,同属于豆科的黄豆-苜蓿混种降解效果最好,而豆科的苜蓿与禾本科羊草混种的组降解效果最差,这说明在实际应用中植物选择要注意搭配的合理性,本次实验证明同种植物混种长势好,降解效果突出。更多还原

【Abstract】 Soil is material base and environmental conditions for human to survive and develop.when oil was brought into soil, it would undergo a series of complex physical, chemical and biological processes in the soil. The scope of oil pollution would be expanded if it infiltrated into the groundwater under gravity and capillary pressure. And the lives and health of animal, plant and human would be endangered directly or indirectly. Therefore, the researches were carried out on the natural migration and transformation law of oil contaminants in soil-water system and the mediation experiment by plants-microbial technology, which had important practical significance for the protection of the soil and water environment.The natural migration and transformation law of oil contaminants in soil-water system is studied in this research. The influencing factors of biological activity of indigenous microorganism were determined by the method of bioslurry. On this basis, the suitable seeds which had be selected through extensive literature survey and field work would be planted in the bioaugmentation soil according to certain laws, thus research on the relationship between the effects of plant-microorganism combined bioremediation and the degradation rate of oil contaminants.1. The migration and transformation law of oil contaminants in soil-water under the natural situationAccording to the experimental purpose, the sampling sites were selected around wells for observing the migration and transformation law of oil contaminants. The results show that the content of petroleum contaminants decreases with increased depth and distance, and only a few hydrophilic contaminants could continue to migrate because of the eluviations. Based on the actual situation in Daqing, the groundwater could not be polluted by petroleum contaminants under the general condition.2. Study on the influencing factors of activating indigenous microorganismThe influencing factors of activating indigenous microorganism were analyzed in the simulated tests in laboratory to determine the concrete method of activating indigenous microorganism. The results indicated that temperature had a great effect to microbial activity, optimal temperature was 40℃. So as the introduction of alien carbon source, and the capacity of various carbon sources were different in activating indigenous microorganism. The result showed that the best effect was when 0.5gC/kg of starch or 0.1gC/kg of glucose were added to Samples. The experiments concluded that the best conditions were: containing water 50%, the proportion of nutrition (N/P) was ten to one, electron accepter(H2O2) was cumulated to 14ml or the content of surfactant equals 50mg/L.However, taking into account the actual operation and the impact on environment , the latter two methods were not be advocated . 3. Research on the bioremediation experiment of plant-microorganismThe basis of preliminary experiments, we would like to select the three plant species: soybeans, alfalfa, and leymus chinensis, according to certain laws in the treated samples. The studies have shown that the samples pre-treated biological activity has been strengthened, with the plant obvious effect of combined bioremediation experiment; after adding starch processing, Planting soybeans - degradation of alfalfa group the best, followed by the soybean; overall, belong to the same legume soybeans - is the best of mixed degradation. But the legume alfalfa and Phocaea Leymus is worst of mixed degradation, this shows that in practical applications with plant selection should focus on the collocations of reasonableness, the results show the same kinds of mixed species of plants are growing well, the degradation effect is prominent.更多还原