登录

  • 登录
  • 忘记密码?点击找回

注册

  • 获取手机验证码 60
  • 注册

找回密码

  • 获取手机验证码60
  • 找回
毕业论文网 > 毕业论文 > 机械机电类 > 过程装备与控制工程 > 正文

自然循环系统气液两相流及基本工艺参数的选择毕业论文

 2022-02-13 08:02  

论文总字数:29128字

摘 要

湿式氧化(WAO)技术因其适用于高盐、高氨氮、高浓度、难降解有机废水的无害化处理,日益成为工业有机废水的重要处理技术之一。为了推动WAO反应器中物料的循环流动,一般选用高温循环泵,其工作条件极为恶劣,长期运行的稳定性和可靠性得不到保证。针对上述问题,本课题采用解析计算和数值模拟方法,设计WAO反应器的物料自主循环系统,实现无泵循环,对其主要结构和工艺参数进行探讨,其主要研究内容如下:

(1)基于WAO小中试实验装置的结构尺寸和工艺参数建立相应的反应器物料自主循环系统。通过解析计算的方法得出冷却段(冷阱)至反应器底部的距离,随之可得出反应器(热阱)顶部至气液分离器之间的垂直高度,从而确定整个循环回路的基本结构参数。

(2)基于解析计算所涉及到的各物理量,确定影响自主循环系统流动速度的各物性参数、结构参数和流动参数,并采用有限元方法对这些影响因素进行单因素试验,根据计算结果确定其取值范围。

(3)依据单因素试验所确定的各因素取值范围,采用正交实验设计法探讨各可控因素对自主循环流量的影响。并基于正交试验设计显著性分析,将其中的非显著因素去除,对显著影响因素采用量纲分析方法得到有关反应器自主循环系统循环流量的拟合方程。

关键词:WAO 自主循环 量纲分析 数值模拟

ABSTRACT

Wet air oxidation technology (WAO) has been presently accepted as one of the important treatment methods of industrial organic wastewater in western countries, being suitable for treating difficult degradation organic wastewater with high organic, ammonia nitrogen and salt concentration. High-temperature circulation pump might be applied in the material circulating system of WAO reactor, but the stability and reliability of the pump can not be consistently guaranteed in one operational cycle. In this thesis, analytical calculation and numerical simulation method were used to design the material autonomic circulatory system of WAO reactor. And main structure and technological parameters of the system were discussed, realization of non pump cycle. The main research contents are as follows:

  1. Based on the structure sizes and technological parameters of small-sized WAO experimental facility, the corresponding material autonomic circulation system of the reactor was established. The distance from the cooling zone (cold trap) to the bottom of the reactor was obtained by analytic calculation. As well, the distance from the top of the reactor (hot trap) to the vapor-liquid separator was worked out. And the basic structural parameters of the whole circulation loop were obtained.
  2. Studying the physical quantities involved in the analytic calculation, physical property parameters, structural parameters and fluid parameters affecting flow velocity of the autonomic circulation system were determined. The single factor experiments were carried out, and the value range of these influence factors were obtained by using FEM calculation.

According to the value range of various influence factors determined by single factor experiments, the orthogonal test design method was adopted to discuss the influences of various controllable factors on the autonomic circulation flow rate. Besides, by using remarkable analysis of orthogonal test design, the nonsignificant influence factors were discarded. And the dimensional analysis was carried out on the remarkable influence factors to obtain the fitted equation of circular flow rate of the autonomic circulation system.

KEYWORDS: Wet air oxidation technology; Autonomic circulation; Dimensional analysis; Numerical simulation

目 录

摘 要 I

ABSTRACT i

第一章 绪 论 1

1.1 研究背景及意义 1

1.2 湿式氧化技术发展及应用 1

1.2.1 湿式氧化技术的部分工艺 1

1.3 自然循环系统 3

1.3.1 自然循环系统的应用 3

1.3.2 自然循环系统的循环影响因素 3

1.3.3 循环系统的工艺参数选择 5

1.4 课题目标及研究内容 6

第二章 湿式氧化反应器自主循环模型的构建 7

2.1 自主循环系统水力模型参数的确定 7

2.2 循环系统有限元模型的建立 13

2.2.1 COMSOL Multiphysics多物理场仿真软件 13

2.2.2 网格划分 13

2.2.3 计算模型 14

2.3 本章小结 15

第三章 反湿式氧化反应器自主循环系统各参数对循环流速的影响 17

3.1 自主循环流动的影响因素 17

3.2 本章小结 26

第四章 循环流量的量纲分析及正交设计 27

4.1 正交试验设计 27

4.2 各影响因素的量纲分析 30

4.3 经济评价 33

4.4 本章小结 33

第五章 结论与展望 35

5.1 主要研究内容和结论 35

5.2 展望 35

参考文献 37

致谢 41

第一章 绪 论

1.1 研究背景及意义

请支付后下载全文,论文总字数:29128字

您需要先支付 80元 才能查看全部内容!立即支付

企业微信

Copyright © 2010-2022 毕业论文网 站点地图