利用微生物和含铁粘土矿物降低焦化废水出水COD的研究
发布时间：2019-03-02 10:04
【摘要】：焦化废水是由复杂的有机污染物构成的,这些有机物性质稳定,其中一些具有致毒和致癌的性质,通常COD值很高,但BOD/COD值却很低,很难被生物降解,处理难度比较大。因此,焦化废水属于典型的难以治理并且具有毒性的废水。喹啉作为本次实验焦化废水中含量最高的有机物,具有潜在致癌性,又难以降解,是目前废水中比较难处理的有机物之一。粘土矿物在自然界中分布非常广泛,并且具有许多优异而又无可替代的性能,因其具有比表面积大、吸附能力强、阳离子交换能力强等特点,是一种优良的环境修复材料,正逐渐被广泛应用与关注。本次实验首先将喹啉作为目标污染物,分离能够降解喹啉的微生物,然后针对喹啉的不完全降解产物,继续分离再降解微生物,使其COD进一步地降低。另外利用经过化学还原后的含铁粘土矿物,在好氧条件下产生羟基自由基,对焦化废水中有机污染物进行无选择性的氧化,以达到降低出水COD目的。同时将粘土矿物和微生物共同作用于焦化废水,分为两种:1、先微生物再粘土矿物。2、先粘土矿物再微生物。对比分析,寻找最有效地降低焦化废水COD的方法。针对污染物喹啉,分离出两株可以共同降解喹啉的微生物,Alcaligenes faecalis和Mesorhizobium sp.。Alcaligenes faecalis降解喹啉的最适pH、温度、盐度分别为8.0、30℃、0.3%,而底物的浓度在500mg/L及以下时,可将其完全降解,另外对于苯酚降解也具有重要的作用。同时Alcaligenes faecalis降解喹啉过程中喹啉中的部分N释放为NH3-N,并且对于产物二羟基喹啉浓度进行了定量分析。通过LC-MS的定性分析,得出了两株菌共同作用后产物的成分,提出了可能的两条降解途径,一条为左侧苯环结构的开环,另一条为右侧含氮杂环的开环。上述结果表明两种菌可以共存,并且Mesorhizobium sp.可以更深度降解喹啉。将微生物和含铁粘土矿物应用于焦化废水,相比于微生物的降解作用,化学还原后的粘土矿物对于焦化废水出水COD的去除率更高,去除效果更好。微生物-粘土矿物模式和粘土矿物-微生物模式,整体上两者最终的COD去除率基本一致。微生物的降解作用在前期的效果更好,因此将微生物-粘土矿物模式选为最优的焦化废水COD去除模式。
[Abstract]:Coking wastewater is composed of complex organic pollutants, some of which have toxic and carcinogenic properties. The COD value is usually very high, but the BOD/ COD value is very low, so it is difficult to be biodegraded and difficult to treat. Therefore, coking wastewater is a typical wastewater which is difficult to treat and toxic. Quinoline, as the organic matter with the highest content in coking wastewater of this experiment, has the potential carcinogenicity and is difficult to degrade, so quinoline is one of the most difficult organic compounds to be treated in the wastewater at present. Clay minerals are widely distributed in nature, and have many excellent and irreplaceable properties. Because of their large specific surface area, strong adsorption ability and strong cation exchange ability, clay minerals are a kind of excellent environmental remediation materials. It is gradually being widely used and paid attention to. In this experiment, quinoline was first used as the target pollutant to isolate the microorganisms that could degrade quinoline, and then to the incomplete degradation products of quinoline, the microorganisms were further separated and redegraded, and the COD of the microorganisms was further reduced. In addition, the organic pollutants in coking wastewater were oxidized non-selectively by using iron-containing clay minerals after chemical reduction to produce hydroxyl radicals under aerobic conditions, in order to reduce the effluent COD. At the same time, clay minerals and microorganisms act together on coking wastewater, and they are divided into two kinds: 1, the first microorganism is followed by clay mineral. 2, the first clay mineral is followed by microorganism. By comparison and analysis, the most effective method to reduce COD in coking wastewater was found. For the pollutant quinoline, the optimum pH, temperature for the degradation of quinoline by, Alcaligenes faecalis and Mesorhizobium sp..Alcaligenes faecalis was 8.0, 30 鈩，
本文编号：2432948
[Abstract]:Coking wastewater is composed of complex organic pollutants, some of which have toxic and carcinogenic properties. The COD value is usually very high, but the BOD/ COD value is very low, so it is difficult to be biodegraded and difficult to treat. Therefore, coking wastewater is a typical wastewater which is difficult to treat and toxic. Quinoline, as the organic matter with the highest content in coking wastewater of this experiment, has the potential carcinogenicity and is difficult to degrade, so quinoline is one of the most difficult organic compounds to be treated in the wastewater at present. Clay minerals are widely distributed in nature, and have many excellent and irreplaceable properties. Because of their large specific surface area, strong adsorption ability and strong cation exchange ability, clay minerals are a kind of excellent environmental remediation materials. It is gradually being widely used and paid attention to. In this experiment, quinoline was first used as the target pollutant to isolate the microorganisms that could degrade quinoline, and then to the incomplete degradation products of quinoline, the microorganisms were further separated and redegraded, and the COD of the microorganisms was further reduced. In addition, the organic pollutants in coking wastewater were oxidized non-selectively by using iron-containing clay minerals after chemical reduction to produce hydroxyl radicals under aerobic conditions, in order to reduce the effluent COD. At the same time, clay minerals and microorganisms act together on coking wastewater, and they are divided into two kinds: 1, the first microorganism is followed by clay mineral. 2, the first clay mineral is followed by microorganism. By comparison and analysis, the most effective method to reduce COD in coking wastewater was found. For the pollutant quinoline, the optimum pH, temperature for the degradation of quinoline by, Alcaligenes faecalis and Mesorhizobium sp..Alcaligenes faecalis was 8.0, 30 鈩，
本文编号：2432948
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