炼厂胺液脱硫系统模拟与优化设计毕业论文
2021-10-17 16:09:31
摘 要
含硫原油在炼化生产过程中,原料油中部分硫化物转化为H2S,H2S最终进入到干气、液化石油气等产品中。如果这些含硫产品脱硫不达标,作为石油化工原料或燃料使用时将会导致设备、管道的腐蚀,最终造成环境污染。因此,对液化石油气、干气进行脱硫处理非常必要。
本设计采用Aspen Plus流程模拟软件,对武汉某炼油厂炼厂气胺液脱硫系统的全流程进行模拟,主要包含干气脱硫塔,液化气脱硫塔,溶剂再生塔等主要分离设备。模拟采用Aspen Plus V8.4自带脱酸性气体数据包,该数据包按电解质系统进行计算,物性方法为ELECNRTL,需要定义亨利组分和电解反应以及化学反应,组分以真实组分来表示。
在模型能反映实际情况的基础上,保证脱硫效果,以节约能耗为目的,应用设计规定和灵敏度分析等工具对吸收剂温度、压力、组成以及用量等参数进行调节,吸收剂温度由36.1℃升高至40℃,塔操作压力不变,吸收剂组成H2O:MDEA:H2S由0.6577:0.3219:0.0204变化为0.586:0.4:0.014,胺液循环量由15吨下降至5吨。优化后比优化前节能931kW,节能55.4%。
根据优化结果对系统进行改造设计,主要针对干气脱硫塔进行了重新设计,同时对部分配套设施重新进行了设备选型和计算,绘制了带控制点的工艺流程图、干气脱硫塔装配图以及车间平面、立面布置图,并编制了设计说明书。
关键词:胺液脱硫;模拟;优化;设计
Abstract
In oil refining process, some of sulfur compounds will convert to H2S, and then get into dry gas and LPG products. If the products are below quality, they will bring lots of problems such as corrosion of equipment and piping, and environmental pollution when they are used as raw petrochemical materials or fuel. Thus it is quite necessary for dry gas and LPG desulfurization.
This design simulated the whole amine sweetening unit, in which the primary separation equipment include the dry gas sweetening tower, the LPG sweetening tower and the solvent regeneration tower in one of oil refineries in Wuhan by using the date packet of removal of sour gas contained in Aspen Plus V.8.4 process simulation program. The packet is calculated by the electrolyte system and method of ELECNRTL, which need to define the Henry components, electrolytic reaction chemical reaction and the component is displayed in true component.
After making the simulation results in accord with the actual situation, design specifications and sensitivity analysis were applied in the optimization of the process. By adjusting the temperature, pressure, composition and quantity of the amine solvent, the energy consumption was reduced. The temperature of the amine solvent changed from 36.1℃into 40℃ while the pressure remained, and the quantity of the amine solvent decreased from 15t to 5t after the composition (H2O:MDEA:H2S) changed from 0.6577:0.3219:0.0204 to 0.586:0.4:0.014. As a result of these changes, the energy consumption decreased 931kW, which means 55.4% decrease.
Then, to revamp the sweetening unit, the dry gas tower and part of the supporting equipment were re-designed. Finally, the process flow chart with control point, assembling drawing, the plan and vertical sections and the design specification were finished.
Key Words: amine desulfurization, simulation, optimization, design
目 录
第1章 绪论 1
1.1 概述 1
1.2 胺法脱硫技术方案 2
第2章 胺液脱硫工艺简述与模拟优化 4
2.1胺液脱硫工艺流程 4
2.2主要设备及操作条件 5
2.3 胺液脱硫系统流程模拟 5
2.3.1 原料气及贫液进料条件与组成 5
2.3.2 建立流程模拟 7
2.3.3 模拟结果对比 8
2.4 胺液脱硫工艺优化设计 9
2.4.1 灵敏度分析 10
2.4.2 胺液脱硫工艺优化结果 15
第3章 干气脱硫塔设计 17
3.1干气脱硫塔的工艺设计 17
3.1.1塔板设计 17
3.1.2塔板校核 20
3.2干气脱硫塔机械设计 21
3.2.1 塔内件设计 22
3.2.2 辅助装置及附件 23
3.2.3 塔的强度和稳定性计算 25
3.3 辅助设备设计 34
3.3.1换热器选型 34
3.3.2储罐 40
3.3.3离心泵选型 40
第4章 车间布置和岗位人员配置 42
4.1车间布置 42
4.2岗位人员配置 42
第5章 设计总结 43
设备一览表 44
主要符号说明: 45
参考文献 46
致谢 47
附录A 48
附录B 48
附录C 48
第1章 绪论
1.1 概述
含硫原油在炼化生产过程中,经过一次和二次加工,原料油中部分硫化物转化为硫化氢,硫化氢最后被携带到干气和液化石油气中。如果这些含硫产品脱硫不合格,作为石油化工原料使用时,在水存在的情况下将会对管道及装置造成腐蚀,含硫燃料燃烧后生成SO2,进一步形成酸雨,造成环境污染。所以,干气、液化石油气脱硫极其必要。
气体脱硫历史悠久。19世纪后期,人们就利用干式氧化铁来脱除含硫化合物中的硫。到了20世纪初,醇胺法逐渐兴起,气体脱硫得到进一步的发展,气体脱硫才逐渐演变成独立的工业分支。干法脱硫和湿法脱硫是常用的脱硫工艺,除此之外还有一些脱硫新方法正在研究开发中。
(1)干法脱硫