【作者】 王苗苗；

【导师】 季民；

【作者基本信息】 天津大学 ， 环境工程， 2007， 硕士

【摘要】 为了进一步降低生化处理后垃圾渗滤液中有机污染物浓度,提高出水水质,本研究分别采用光催化氧化、TiO₂/O₃/UV、O₃/UV、O₃工艺对经生化处理后的垃圾渗滤液进行深度处理小试,探讨了垃圾渗滤液中有机污染物降解的影响因素及其降解机理。以ZnO_作为光催化剂,利用光催化氧化技术处理垃圾渗滤液,试验设计及结果分析都用响应曲面法,得到COD去除率最大值39%时的反应条件为:催化剂投加量为9g/L,反应时间75min,初始CO_D浓度为440mg/L;UV254去除率到达最大值42.4%时的反应条件为:催化剂投加量为9.37g/L,反应时间120min,初始CO_D浓度为771mg/L。光催化氧化与臭氧结合可以大大提高降解效率,COD去除率可以提高20%³0%,UV254去除率以提高40%⁶0%。利用TiO₂/O₃/UV工艺处理垃圾渗滤液,TiO₂的最佳投加量为0.5g/L;最佳反应时间为2.0h;臭氧浓度16.8mg/L;垃圾渗滤液初始浓度在430mg/L以下,不调pH值时可以得到理想的处理效果。此外,该工艺还可以大幅提高垃圾渗滤液的可生化性。TiO₂/O₃/UV、O₃/UV、O₃三种工艺处理垃圾渗滤液进行对比,试验结果表明: TiO₂/O₃/UV工艺在垃圾渗滤液初始COD浓度为433mg/L左右,臭氧浓度16.8mg/L的条件下,降解有机物的速率明显高于其他两种工艺;三种工艺达到同样的处理效果,所需的反应时间TiO₂/O₃/UV<O₃/UV<O₃,相比较于O₃/UV工艺,采用TiO₂/O₃/UV工艺可以节约20³0min,相较于O₃工艺,可以节约30⁹0min,臭氧的成本较高,所以节约时间就是节约成本,因而对于垃圾渗滤液的深度处理,TiO₂/O₃/UV工艺优于其他两种工艺。更多还原

【Abstract】 To improve the effluent quality and reduce pollutant concentration in landfill leachate, the processes of photocatalytic oxidation, TiO₂/O₃/UV, O₃/UV and O₃ were used to treat the effluent treated by biological processes. The effects of initial COD concentration, dose of photocatalyst, concentration of ozone and reaction time were evaluated.In the photocatalytic experiment, ZnO was chosen as the photocatalyst, response surface methodology was used to design the experiment and interpret the result. The COD removal was up to 39% under the conditions that photocatalyst was 9g/L, and reaction time was 75min, as well as initial COD concentration of landfill leachate was 440mg/L. The UV254 removal was up to 42.4% under the conditions that photocatalyst was 9.37g/L, and reaction time was 120min, as well as initial COD concentration was 771mg/L. The COD removal could be increased to 20%³0% and UV₂₅₄ removal could be increased to 40%⁶0% with photacatalysis and ozone.During TiO₂/O₃/UV process, the result indicated that the process was effective under the conditions that the dose of TiO₂ 0.5g/L, the reaction time 2.0h, the concentration of ozone 16.8mg/L, the initial COD concentration less than 430mg/L, and pH neutral. In additon, the process could improve the biodegradability of landfill leachate obviously.Comparing the processes of TiO₂/O₃/UV, O₃/UV and O₃, it was found that TiO₂/O₃/UV was more effective than others in degrading organic matters under the conditions that the initial COD concentration of landfill leachate was 433mg/L and the concentration of ozone was 16.8mg/L. The result also indicated that the reaction time was different （TiO₂/O₃/UV<O₃/UV<O₃） when the three processes achieve the same treatment effect. The reaction time of TiO₂/O₃/UV was less 20³0min than by O₃/UV, and less 30⁹0min than by O₃. Because the cost of ozone is more expensive, saving time means saving cost. TiO₂/O₃/UV is better than others in advanced treatment of landfill leachate.更多还原