摘要
为了揭示膜滤浓缩液反硝化产水总氮(TN)无法达标排放的主要原因,以湖南某地卫生填埋场垃圾渗滤液膜滤浓缩液(LLMC)为研究对象,选择葡萄糖为碳源,采用SBR反应器,探究Fenton氧化处理前后LLMC在反硝化过程的氮元素变化规律,选择纯化后商品腐殖酸(PCHA)模拟LLMC中主要溶解性含氮有机物,考察PCHA浓度对反硝化脱氮效果的影响以及PCHA在Fenton氧化前后的氮元素变化规律。结果表明,在碳源充足的情况下,LLMC反硝化产水TN高达100.25 mg/L,其中无机氮和有机氮含量分别为15.17、85.08 mg/L;LLMC经Fenton氧化后,其反硝化产水TN降至24.38 mg/L,其中无机氮和有机氮含量分别为6.63、17.75 mg/L,即反硝化产水TN达到了我国《生活垃圾填埋场污染控制标准》(GB 16889-2008)的排放要求。因此推断,LLMC反硝化产水TN无法达标排放的主要原因是LLMC中存在大量的有机氮。PCHA浓度对反硝化的影响表现为随着PCHA浓度的升高,反硝化产水TN逐步升高,当PCHA浓度为2 500 mg/L时,产水TN含量为86.74 mg/L,不能实现TN的达标排放,说明LLMC中大量的溶解性含氮有机物不利于反硝化脱氮。PCHA经Fenton氧化后,其有机氮含量减少、NH_(4)^(+)-N含量增加,部分有机氮转化为NH_(4)^(+)-N,这与LLMC经Fenton氧化后的氮元素变化规律相一致。
To reveal the main reason why the total nitrogen(TN) in the denitrification effluent of the membrane concentrate could not meet the discharge standard, the membrane concentrate from a sanitary landfill(LLMC) in Hunan province was selected as the research object. Glucose was used as a carbon source, and the SBR reactor was used to explore the changes of nitrogen in the denitrification process of the LLMC before and after the Fenton oxidation treatment. The purified commercial humic acid(PCHA) was selected to simulate the main dissolved organic nitrogen matter in the LLMC.The effect of PCHA concentration on the denitrification and the nitrogen changes of PCHA before and after the Fenton oxidation were investigated. The results showed that the TN in denitrification effluent of the LLMC was as high as 100.25 mg/L under the condition of sufficient carbon source, and the contents of inorganic nitrogen and organic nitrogen were 15.17 and 85.08 mg/L, respectively. After the LLMC was oxidized by Fenton, the TN of denitrification effluent decreased to 24.38 mg/L, and the contents of inorganic nitrogen and organic nitrogen were 6.63 and 17.75 mg/L, respectively.Then the TN of denitrification effluent meets China’s standard for pollution control on the Landfill Site of Municipal Solid Waste(GB16889-2008). It was inferred that the main reason of the TN failure by LLMC denitrification is the presence of a large amount of organic nitrogen in the LLMC. The effect of PCHA concentrations on denitrification showed that the TN of denitrification effluent increased gradually with the increase of PCHA concentrations. When the PCHA concentration was 2 500 mg/L, the TN content of denitrification effluent was 86.74 mg/L, which could not meet the discharge standard of TN. The results indicated that a large amount of soluble nitrogen-containing organic matter in the LLMC is not conducive to denitrification. After the PCHA was oxidized by Fenton, the content of organic nitrogen was decreased, the content of NH_(4)^(+)-N was increased, and part of the organic nitrogen was converted into NH_(4)^(+)-N, which was consistent with the change rule of nitrogen in the LLMC after Fenton oxidation.
作者
刘颖
胡慧萍
彭奇凡
彭全凡
LIU Ying;HU Huiping;PENG Qifan;PENG Quanfan(School of Chemistry and Chemical Engineering,Central South University;Changsha Huadi Water Treatment Technology Co.Ltd.,Changsha 410083,China)
出处
《水处理技术》
CAS
CSCD
北大核心
2023年第2期132-138,共7页
Technology of Water Treatment
基金
长沙市科技计划重点项目(kh1902280)。
