【作者】 孙春燕；

【导师】 王增长；

【作者基本信息】 太原理工大学 ， 环境工程， 2011， 硕士

【摘要】 焦化废水是在生产煤气、焦油、焦炭以及其它一些焦化产品的过程中产生的,它主要含有氨氮、酚类、氰化物、硫化物、油份等,属有毒有害难降解的有机工业废水,处理难度很大,焦化废水的处理问题已成为现阶段环境保护领域急需解决的一个难题。目前,我国在焦化废水处理方面普遍采用的方法是：首先对高浓度的焦化废水采用溶剂萃取脱酚和蒸氨,经过预处理的出水与其他废水混合后进入废水处理设施,经调节、隔油沉淀、生物处理等过程后排放。这些工艺对酚类、氰化物等易降解有机物有很好的处理效果,但是对于多环芳烃和杂环化合物等难降解有机物的处理效果并不理想,出水COD和氨氮的浓度较高,无法满足废水排放标准的控制要求,给环境和人体带来危害。针对目前焦化废水处理效果不理想的情况,本课题研究采用了超临界水氧化法(SCWO)处理的新工艺。超临界水氧化法在处理高浓度难降解废水方面有独特优势,是近年发展起来的一项绿色环保处理技术。本文以超临界水的特性为出发点,详细阐述了SCWO技术的特点,并对国内外在SCWO技术上的研究进展进行了较全面的综述。以此为基础,利用自行设计的SCWO处理装置,以焦化废水中COD、氰化物及硫氰化物为主要研究对象,对其反应规律进行了较深入的研究,得出以下实验结论：1、焦化废水的SCWO处理效果较好,在最佳试验条件下,三项指标去除率均可高达95%以上,说明SCWO技术是一种高效水处理技术；2、单因素试验结合正交试验结果表明,单因素对于SCWO处理焦化废水中COD去除率影响的大小顺序为：停留时间>过氧倍数>系统温度>系统压力,并得出SCWO技术处理焦化废水的最佳工艺：N=2.5、t=56.34s、T=480℃、P=26MPa;3、以双氧水为氧化剂时,在系统温度460℃,反应压力26MPa,停留时间34.16s的条件下,水中COD的去除率与过氧倍数的增加几乎呈线性关系,所拟合方程为：y=21.724+17.726, R2=0.8663,相关系数R较高超过0.9,但当过氧倍数增加到2.5时,它的再增加对于三项指标去除率的影响不大；4、对于SCWO处理焦化废水的动力学方面,本实验采用了幂指数方程法,在过氧2.5倍,反应压力26MPa条件下,根据实验所得数据,得出了动力学方程的参数,如下表：最后计算得到动力学反应方程的活化能En=37.993KJ/mol,指前因子k0=21.97;5、分析阐述了SCWO技术的应用前景,为实现绿色水处理的应用提供了进一步的理论依据,最后总结了SCWO技术工程应用中出现的问题。更多还原

【Abstract】 Coking wastewater is in the production of gas, tar, coke and other products generated in the process of coking, which contains mostly nitrogen, phenols, cyanide, sulfide, oil, etc, are toxic refractory organic industrial wastewater treatment very difficult problem of coking wastewater treatment has become the field of environmental protection need to be resolved at this stage is a difficult problem.At present, the widespread using method of coking wastewater treatment in our country is:First, high concentrations of coking wastewater by solvent extraction from phenol and ammonia, after pretreatment of the water mixed with other waste water into the wastewater treatment facilities, by regulation, grease sedimentation, biological treatment processes before being discharged. The process for phenol, cyanide and other easily biodegradable organic compounds have a good treatment effect, but polycyclic aromatic hydrocarbons and heterocyclic compounds such as the treatment effect of refractory organic matter is not ideal, the effluent COD and ammonia nitrogen high concentration, can not meet control requirements of wastewater discharge standards, bring harm to the environment and the human body.In view of the present coking wastewater treatment effect is not the ideal situation, the research uses supercritical water oxidation (SCWO) processing of new technology. Supercritical water oxidation in dealing with high concentrations and hard-degradation waste water has unique advantages, is developed in recent years as a green environmental protection treatment technology. Based on the characteristics of supercritical water as the starting point, this paper expounds the characteristics of SCWO technology at home and abroad, and the research on technology in SCWO reviewed comprehensively reviewed. Based on this, using self-designed SCWO system in coking wastewater treatment plant, COD, cyanide and sulfur in as the main research object, cyanide to its reaction rules were more detailed study, draw the following conclusion:1. SCWO treatment of coking wastewater is better, in the experimental condition, three indicators can be as high as 95% removal rate, indicating that SCWO technology is a highly efficient water treatment technology;2. The single factor experiment, combined with orthogonal test results show that the single factor for SCWO processing coking wastewater in the size of the CODremoval would affect order:retention time> crosses oxygen multiples> system temperature> system pressure, and draw the SCWO technology for the treatment of the coking wastewater optimal process:N=2.5, t=56.34 s, T= 480℃,P=26MPa;3. With hydrogen peroxide as the oxidant, in the system temperature 460℃, reaction pressure of 26MPa, under the conditions of retention time of 34.16s, water under the condition, The removal rate of COD in water increases with the peroxide multiples almost linear relationship.fitting equation is y=21.724+17.726, R2=0.8663,Correlation coefficient R is higher, more than 0.9, but when crosses oxygen increased to 2.5, multiple add to it is little affected removal three indexes;4. For the dynamics of SCWO processing coking wastewater, this experiment used the power exponent equation method,under the conditions of 2.5 times in oxygen、reaction pressure 26MPa,according to the experimental data, it is concluded that the dynamic equation of parameters, the list below:Finally calculated the activation energy dynamic response equation En= 37.993 KJ/mol, refers to the former factor ko= 21.97;5. Analyses the technical application prospect, SCWO for realizing green water processing the application to provide further theoretical basis, finally summarized the SCWO technical engineering application problems, puts forward the corresponding solutions.更多还原