The invention discloses a process for recovering dichloromethane from waste gas. The specific steps are as follows: first, the waste gas containing dichloromethane is introduced to the bottom of the dichloromethane absorption tower, and the lean white oil is sent to the top of the dichloromethane absorption tower. After the two phases are in counter-current contact in the tower, the tail gas from the top of the tower is directly discharged into the atmosphere, and the rich white oil is sent to the decomposition. Absorption tower, the dichloromethane absorption tower has five theoretical versions, the operating pressure is atmospheric pressure, the temperature of lean white oil is about 20 C, the temperature of exhaust gas is about 20 C, and the temperature of rich white oil is about 24 C. The second step is to introduce the first step of rich white oil in the upper and middle part of the desorption tower, and the steam at the top of the desorption tower is extracted and condensed by a dry vacuum pump. After reflux, a dichloromethane liquid is produced, which is preheated with the analysed poor white oil, then cooled to 20 C and returned to the dichloromethane absorption tower for reuse. The desorption tower consists of five theoretical plates with an operating pressure of about 10 kPa. The liquid feeding position of the desorption tower is at the upper and middle parts of the desorption tower, and the temperature of the desorption tower kettle is 170-175. Centigrade.
【技术实现步骤摘要】
一种废气中二氯甲烷的回收工艺
本专利技术涉及一种排放废气中二氯甲烷的回收工艺。
技术介绍
在常规的化工萃取过程中,二氯甲烷是常用的有机萃取剂。二氯甲烷的沸点很低,为39.8℃,挥发性较高,具有一定的毒性,对于人的中枢神经系统和呼吸系统有危害,并且其溶液还具有腐蚀性。二氯甲烷废气直接排放将对大气造成较大污染,对操作人员的身体造成损害,并影响周围生活居民的环境。
技术实现思路
本专利技术的目的在于提供一种废气中二氯甲烷的回收工艺。该回收工艺通过二氯甲烷吸收塔用贫白油对废气中的二氯甲烷进行吸收,在塔顶得到可直接排放到大气的尾气,吸收后的富白油经换热器换热后进入解吸塔进行解吸,塔顶气相经冷凝后得到纯度较高的二氯甲烷液体,塔釜解吸后的贫白油经换热器给富白油预热后在经冷却器回到吸收塔套用。为了实现上述二氯甲烷回收的目的,本专利技术提供一种废气中二氯甲烷的回收工艺,具体步骤是:第一步,将含有二氯甲烷的废气引入二氯甲烷吸收塔的底部,将贫白油送入二氯甲烷吸收塔的顶部,两相在塔内逆流接触后,将塔顶尾气直排大气,将富白油送入解吸塔,所述二氯甲烷吸收塔共5块理论版,操作压力为常压,贫白油的温度为20℃左右,废气的进气温度为20℃左右,富白油温度约24℃;第二步,在解吸塔中上部引入第一步的富白油,解吸塔塔顶蒸汽经干式真空泵抽出并冷凝后后回流,并采出二氯甲烷液体,用解析后的贫白油给富白油预热,而后冷却到20℃回到二氯甲烷吸收塔回用;所述解吸塔共5块理论版,操作压力10kPa左右,解吸塔液体进料位置为解吸塔的中上部位置处,解吸塔塔釜温度为170~175℃。附图说明图1本专利技术中的无组织排 ...
【技术保护点】
1.一种废气中二氯甲烷的回收工艺,具体步骤是:第一步,将含有二氯甲烷的废气引入二氯甲烷吸收塔的底部,将贫白油送入二氯甲烷吸收塔的顶部,两相在塔内逆流接触后,将塔顶尾气直排大气,将富白油送入解吸塔,所述二氯甲烷吸收塔共5块理论版,操作压力为常压,贫白油的温度为20℃左右,废气的进气温度为20℃左右,富白油温度约24℃;第二步,在解吸塔中上部引入第一步的富白油,解吸塔塔顶蒸汽经干式真空泵抽出并冷凝后后回流,并采出二氯甲烷液体,用解析后的贫白油给富白油预热,而后冷却到20℃回到二氯甲烷吸收塔回用;所述解吸塔共5块理论版,操作压力10kPa左右,解吸塔液体进料位置为解吸塔的中上部位置处,解吸塔塔釜温度为170~175℃。
【技术特征摘要】
2017.04.14 CN 20171024718831.一种废气中二氯甲烷的回收工艺,具体步骤是:第一步,将含有二氯甲烷的废气引入二氯甲烷吸收塔的底部,将贫白油送入二氯甲烷吸收塔的顶部,两相在塔内逆流接触后,将塔顶尾气直排大气,将富白油送入解吸塔,所述二氯甲烷吸收塔共5块理论版,操作压力为常压,贫白油的温度...
【专利技术属性】
技术研发人员:项威,姚红果,丁少峰,陈学青,来庆发,王庆云,宋兴豪,陈干英,张伟,
申请(专利权)人:山东爱地高分子材料有限公司,石家庄工大化工设备有限公司,
类型:发明
国别省市:山东,37
还没有人留言评论。发表了对其他浏览者有用的留言会获得科技券。