回收草铵膦生产废溶剂中有用组分的应用研究

发布时间：2018-03-15 06:35

本文选题：草铵膦　切入点：废溶剂　出处：《南京师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：草铵膦是重要的除草剂,其生产量近年来增长迅速,草铵膦生产过程中需要用到多种溶剂,相关企业面临着大量的废溶剂回收再利用问题。本文系统地总结了当前国内外草铵膦的生产现状以及生产过程中产生混合废溶剂的种类和处理办法。由于生产流程的差异,草铵膦生产过程中主要产生两种混合废溶剂,经企业初步处理后,其组成分别为：废溶剂A(四氢呋喃35.0 wt%、甲基亚磷酸二乙酯15.0 wt%、亚磷酸三乙酯2.0 wt%及三甲苯48.0 wt%)以及废溶剂B(四氢呋喃38.0 wt%、二溴乙烷14.0 wt%、亚磷酸三乙酯4.0 wt%、三甲苯44.0 wt%)。其中主要成分四氢呋喃、甲基亚磷酸二乙酯、二溴乙烷、亚磷酸三乙酯、三甲苯都是重要化工原料,必须采用合适的工艺路线回收这些物料,使其能够循环利用,同时降低企业的环保压力。针对废溶剂A,设计了三种工艺流程用以回收其中的四氢呋喃、甲基亚磷酸二乙酯、亚磷酸三乙酯、三甲苯等有用组分。这三种流程分别为常压三塔串联连续精馏、单塔侧线出料精馏后接单塔连续精馏和单塔双侧线出料精馏,通过Aspen Plus化工流程模拟软件模拟计算,以产品的纯度、收率、能耗及设备造价为指标,考察分析确定单塔侧线出料精馏后接单塔连续精馏为最佳的工艺方案,并进一步通过单因素实验结合正交实验设计的方法考察了塔板数、进料位置、回流比以及侧线出料位置等工艺参数对回收结果的影响。在模拟计算基础上,设计了单塔侧线出料精馏实验装置并进行了实验研究,实验结果表明,在优化的工艺条件下,所回收的四氢呋喃纯度达到99.7%、收率为99.1%,甲基亚磷酸二乙酯纯度达到98.6%、收率为98.0%,亚磷酸三乙酯纯度达到95.1%、收率为94.2%,三甲苯的纯度达到98.1%、收率为97.5%1所回收产品的纯度均达到企业循环利用的标准。针对废溶剂B,同样设计了三种工艺流程用以回收其中的四氢呋喃、二溴乙烷、亚磷酸三乙酯、三甲苯等有用组分。这三种流程分别为常压三塔串联连续精馏、单塔侧线出料精馏后接连续萃取精馏和单塔双侧线出料精馏,通过AspenPlus化工流程模拟软件模拟计算,以产品的纯度、收率、能耗及设备造价为指标,考察分析确定单塔侧线出料精馏后接连续萃取精馏为最佳的工艺方案,并进一步通过单因素实验结合正交实验设计的方法考察了塔板数、原料进料位置、萃取剂进料位置、回流比、侧线出料位置以及溶剂比等工艺参数对回收结果的影响。在模拟计算基础上,设计了单塔侧线出料精馏实验装置、萃取精馏实验装置并进行了实验研究,实验结果表明,在优化的工艺条件下,所回收的四氢呋喃纯度为99.0%、收率为98.6%,二溴乙烷纯度为96.5%、收率为89.9%,亚磷酸三乙酯纯度为99.0%、收率为93.2%,三甲苯的纯度为99.0%、收率为98.5%；所回收产品的纯度均达到企业循环利用的标准。本文所做工作为草铵磷生产中废溶剂的回收循环利用提供了新的解决方案。
[Abstract]:Phosphine oxalate is an important herbicide, and its production has been increasing rapidly in recent years. The related enterprises are faced with a large number of waste solvent recovery and reuse problems. This paper systematically summarizes the current production situation of ammonium phosphine at home and abroad, and the types and treatment methods of mixed waste solvents in the production process. Two kinds of mixed waste solvents are mainly produced in the production process of ammonium phosphine. After preliminary treatment by enterprises, The composition of the waste solvent A (tetrahydrofuran 35.0 wtand methyl diethyl phosphite 15.0 wtt, triethyl phosphite 2.0 wt% and trimethylbenzene 48.0 wtt respectively) and the waste solvent B (tetrahydrofuran 38.0 wtt, dibromoethane 14.0 wtth, triethyl phosphite 4.0 wt, trimethylbenzene). 44.0 wts. the main component of tetrahydrofuran is tetrahydrofuran, the main component of which is tetrahydrofuran. Diethyl methyl phosphite, dibromoethane, triethyl phosphite and trimethylbenzene are all important chemical raw materials. At the same time, the environmental pressure of the enterprise was reduced. For the waste solvent A, three processes were designed to recover the tetrahydrofuran, methyl diethyl phosphite and triethyl phosphite. The three processes are series continuous distillation under atmospheric pressure, continuous distillation with single column side line and single column with double side line distillation. The simulation calculation is carried out by Aspen Plus chemical process simulation software. Taking the purity, yield, energy consumption and equipment cost of the product as the index, the best process scheme was determined by investigating and analyzing the single column side line discharge rectification followed by single column continuous distillation. The effects of the process parameters, such as plate number, feed position, reflux ratio and side line discharge position, on the recovery results were investigated by single factor experiment and orthogonal design. The experimental equipment of single column side line discharge distillation is designed and studied. The experimental results show that, under the optimized technological conditions, The purity of the recovered tetrahydrofuran is 99.7, the yield is 99.1, the purity of diethyl methyl phosphite is 98.6, the yield is 98.0, the purity of triethyl phosphite is 95.1 percent, the yield is 94.2 percent, the purity of trimethylbenzene is 98.1 and the purity of the recovered product is 97.51. For waste solvent B, three processes were also designed to recover tetrahydrofuran. The three useful components, such as dibromoethane, triethyl phosphite and trimethylbenzene, are serially rectified in series with three columns under atmospheric pressure, followed by continuous extraction distillation in a single side line and a double side line extraction distillation in a single column. Through the simulation calculation of AspenPlus chemical process simulation software, taking the purity, yield, energy consumption and equipment cost of the product as the index, the optimum technological scheme was determined by investigating and analyzing the single column side line discharge rectification followed by continuous extractive distillation. Furthermore, the number of trays, the feed position of raw materials, the feed position of extractant and the ratio of reflux were investigated by single factor experiment and orthogonal design. On the basis of simulation calculation, a single column side line extraction distillation experimental device and an experimental device for extractive distillation are designed and studied. The experimental results show that the recovery results are affected by the side line discharge position and solvent ratio. Under the optimized technological conditions, The purity of the recovered tetrahydrofuran is 99.0, the yield is 98.6um, the purity of dibromoethane is 96.55.The yield is 89.9. the purity of triethyl phosphite is 99.0, the purity of triethyl phosphite is 99.0, the purity of trimethylbenzene is 99.0, and the purity of trimethylbenzene is 98.5.The purity of the recovered products reaches the enterprise recycling profit. The work in this paper provides a new solution for recycling waste solvent in ammonium oxalate production.
【学位授予单位】：南京师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X786

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