【作者】 韩龙叶；

【导师】 刘广民；

【作者基本信息】 哈尔滨工程大学 ， 环境工程， 2011， 硕士

【摘要】 在有毒有机化学品的生产、贮存、运输及使用过程中,经常会发生突发性泄漏事故,造成土壤点源污染。这些污染物对生态环境和人体健康有很大危害,而且若不能及时去除,它们会长期存在于土壤中。因此,在土壤点源污染事故发生后,为了最大限度地减少事故带来的环境危害,对污染物进行快速降解处理十分必要。本文以苯酚(Phenol)为目标污染物,采用高铁酸钾氧化法处理苯酚模拟污染土壤。通过对苯酚处理效果影响因素的研究,确定了最佳的工艺操作条件,实现了工艺的自动控制。通过HPLC法测定该反应的中间产物和最终产物,并推断出高铁酸钾氧化降解苯酚的反应途径。本文实验结果表明,高铁酸钾法氧化处理土壤中苯酚的最佳条件为：泥水混合液的土水比为1：1-1：4,高铁酸钾与苯酚的摩尔比为7.5：1,体系初始pH值为7.0-9.0(用2%的稀硫酸调节),分批少量投加高铁酸钾,每次投加量为0.15g/kg土,同时在搅拌条件下,苯酚去除率可达95%。整个反应过程迅速,可在10min内完成。反应后的泥水混合液经泥水分离后的上清液用2%的硫酸调节pH值至近中性,可以多次循环使用。反应后需要排放的泥土及反应液体中残余的氧化剂可通过加入硫酸亚铁来还原,消除氧化剂对环境的影响。根据体系的中间产物,推断出高铁酸钾氧化降解苯酚的主要途径为：苯酚→对苯醌→顺丁烯二酸→草酸→甲酸→二氧化碳和水。高铁酸钾氧化体系在反应过程中pH值会不断升高,通过监控体系中pH的变化,设计出一套适于高铁酸钾氧化降解土壤污染物的工艺流程及自动控制方法,实现了工艺的自动控制过程。本文研究结果对快速处理点源污染土壤有借鉴作用。更多还原

【Abstract】 Chemical leaking accidents which could cause serious point source soil contamination happened frequently in the storage, transportation and usage of hazardous chemicals. These chemicals are extremely detrimental to ecological environment and human health, and they would chronically exist in the soil and strongly bound to the soil matrix if they can not be eliminated immediately. To eliminate the negative impacts of these accidents, rapid on-site disposal of the contaminated soil would be highly necessary.In this paper, phenol was selected as the target contaminant and the simulant phenol contaminated soil was treated with Potassium Ferrate Oxidation Method. Through the study of the influencing factors of phenol degradation efficiency, optimum operating conditions were identified. Automatic control of the whole treatment process was achieved. The final products and intermediates of the reaction were also identified by HPLC method and the reaction pathway of phenol degradation by potassium ferrate was concluded.Through single-factor experiments, the optimum operating conditions were identified as follows:soil-water ratio of the slurry 1:1-1:4; phenol-potassium ferrate molar ratio 7.5:1; initial system pH 7.0～9.0 (adjusted by 2% sulfuric acid); moderate mixing; potassium ferrate was added into the reactor in batches, dosing amount 0.15 g/batch. Under optimum conditions, the degradation efficiency of phenol reached up to 95% and the whole reaction process was done in 10 min. After each round of reaction, the supernatant of the slurry can be reused in the next round after its pH was adjusted to neutral by 2% sulfuric acid. To eliminate the bad impacts of the residual oxidant, ferrous sulfate can be added into treated soil to neutralize excessive oxidant. Based on the fact that system pH kept increasing during the reaction process, automatic control of the dosing of potassium ferrate was achieved through the monitoring of system pH value. The process flow of potassium ferrate treating point source phenol contaminated soil was further designed to establish an integrated method. Based on HPLC testing results and the intermediate product, the reaction pathway was concluded as follows: The research results of this paper can be used as a reference for practical applications.更多还原