三乙胺冷芯盒制芯尾气处理技术的研究

发布时间：2018-12-15 23:18

【摘要】：三乙胺冷芯盒制芯是1968年由美国Ashland油脂化学公司向铸造界推出的一种制芯技术,凭借其生产效率高、砂芯尺寸精度高、溃散性好、综合成本低等众多优点,推出不久便受到国内外铸造行业的欢迎,并得到了广泛的应用。时至今日,它已成为铸造行业最常用的制芯工艺。但是,在三乙胺冷芯盒制芯过程中产生的含三乙胺尾气,有毒,不仅污染了大气环境,而且对人的身体健康有害。采用经济、有效的方法解决三乙胺冷芯盒制芯过程中产生的含三乙胺尾气污染及胺回收问题,对铸造行业可持续发展和我国的生态文明建设具有重要的现实意义。目前,有机废气处理的方法有液体吸收法、吸附法、燃烧法、膜分离法、冷凝法、生物法、等离子体法等,但是针对铸造生产中产生的含三乙胺尾气治理问题的研究少见报道。为解决三乙胺冷芯盒制芯尾气处理及胺回收问题,本课题先后开展了活性炭吸附三乙胺可行性研究、活性炭吸附三乙胺后的脱附技术研究和冷凝法回收三乙胺技术研究,确定了“活性炭吸附+脱附+冷凝回收”的冷芯盒制芯含三乙胺尾气处理的技术方案,通过活性炭吸附解决三乙胺有机废气处理问题,然后将吸附的三乙胺从活性炭中解附出来,通过冷凝的方式加以回收,从而实现了冷芯盒制芯过程中含三乙胺尾气净化及胺的回收。对活性炭吸附三乙胺的吸附量、适宜吸附层厚度、脱附率、回收率等相关参数进行了实验研究,发现活性炭对三乙胺的吸附量随活性炭层厚度的增加而增加,当吸附饱和时,单位质量活性炭吸附三乙胺的量为0.0389g/g；三乙胺尾气中胺的去除率随活性炭厚度的增加而增加,当活性炭厚度达到65mm时,三乙胺尾气中胺的去除率达到100%；吸附三乙胺后活性炭的胺脱附率随脱附时间的延长呈现先急剧增加,后趋于平缓的变化趋势,胺脱附率不随活性炭吸附-脱附三乙胺次数的增加而变化；脱附后三乙胺的回收率随空胺比的增加而降低,随冷凝水温度的降低而升高。依据三乙胺冷芯盒制芯尾气处理及胺回收技术方案和实验研究所得到的结果,开发了一种具有胺回收功能的三乙胺尾气处理装置。该装置由预处理器、尾气处理器和胺回收器三部分组成,预处理器是用于将尾气中夹杂的粉尘等固体颗粒去除；尾气处理器是利用活性炭对有机气体的吸附性,将尾气中三乙胺吸附下来,使之得到净化,然后利用活性炭的脱附性,将三乙胺从活性炭中解附出来；胺回收器是将脱附出的三乙胺气体液化成液体,进而将其回收,从而解决了三乙胺冷芯盒制芯尾气的处理问题,同时又实现了三乙胺的回收利用。
[Abstract]:Triethylamine cold core box core-making is a kind of core-making technology introduced by Ashland Oil Chemical Company of America in 1968. It has many advantages, such as high production efficiency, high precision of sand core size, good collapsibility and low comprehensive cost, etc. It was welcomed by the foundry industry at home and abroad soon after its launch and has been widely used. Today, it has become the foundry industry the most commonly used core-making process. However, the tail gas containing triethylamine produced in the core-making process of triethylamine cold box is toxic, which not only pollutes the atmospheric environment, but also is harmful to human health. Using economical and effective methods to solve the pollution of triethylamine tail gas and the recovery of triethylamine in the core-making process of triethylamine cold core box has important practical significance for the sustainable development of foundry industry and the construction of ecological civilization in China. At present, organic waste gas treatment methods include liquid absorption method, adsorption method, combustion method, membrane separation method, condensation method, biological method, plasma method, etc. However, there are few reports on the treatment of tail gas containing triethylamine in foundry production. In order to solve the problems of tail gas treatment and amine recovery in the core-making of triethylamine, the feasibility of activated carbon adsorption of triethylamine, the desorption of triethylamine by activated carbon and the recovery of triethylamine by condensation were studied. The technical scheme for the treatment of tail gas containing triethylamine in the core of "adsorption and desorption of activated carbon and condensate recovery" was determined, and the treatment problem of organic waste gas of triethylamine was solved by adsorption of activated carbon. Then, the adsorbed triethylamine was desorbed from the activated carbon and recovered by condensation, thus the tail gas purification and amine recovery were realized in the core-making process of the cold core box. The adsorption amount of triethylamine on activated carbon, suitable adsorption layer thickness, desorption rate and recovery rate were studied experimentally. It was found that the adsorption amount of triethylamine on activated carbon increased with the thickness of activated carbon layer, and when the adsorption was saturated, the adsorption capacity of triethylamine on activated carbon increased with the increase of the thickness of activated carbon layer. The amount of triethylamine adsorbed by activated carbon per unit mass is 0.0389g / g; The removal rate of amine in tail gas of triethylamine increased with the increase of the thickness of activated carbon. When the thickness of activated carbon reached 65mm, the removal rate of amine in tail gas of triethylamine reached 100. After adsorption of triethylamine, the desorption rate of activated carbon increased sharply with the prolongation of desorption time, and then tended to be gentle, and the desorption rate of amine did not change with the increase of the number of times of adsorption and desorption of triethylamine. The recovery of triethylamine after desorption decreased with the increase of air-amine ratio and increased with the decrease of condensation water temperature. A triethylamine tail gas treatment unit with the function of amine recovery was developed according to the technical scheme and experimental results of core-making tail gas treatment of triethylamine cold core box. The device consists of three parts: preprocessor, tail gas processor and amine collector. The preprocessor is used to remove the dust and other solid particles in the tail gas. The tail gas processor uses activated carbon to adsorb organic gas, adsorbs triethylamine from tail gas, makes it purify, and then uses the desorption property of activated carbon to remove triethylamine from activated carbon. The amine collector liquefies the desorption triethylamine gas into a liquid and then reclaims it, thus solving the problem of treating the tail gas from the core making of the cold core box of triethylamine, and at the same time realizing the recovery and utilization of the triethylamine.
【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG242.7

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