低尘烟气螺旋翅片管式油加热器的设计毕业论文
2020-06-19 22:24:55
摘 要
近年来,大气污染问题和化石能源日益衰竭问题成为了人们日常生活不可回避的话题。因而,各领域的科研人员同样纷纷聚焦于此,而此类问题的关键在于如何滞止环境恶化与提高能源利用率,从而引发了当今世界最为首要的大话题——节能减排。
目前,一些导热油锅炉由于排烟温度高,热量浪费较大,炉体热效率较低,一般导热油锅炉出口烟气温度大约在300℃左右,导热油锅炉热效率很低。本课题结合国家节能减排的大政方针,沿着科研与生产相结合的原则,进行余热生产锅炉用给水,提高系统的热效率。
本课题旨在设计出一台螺旋翅片管式油加热器,以改善导热油锅炉热效率低的现状。在整个设计过程中,将工作分为了几个阶段,然后逐步进行。第一步,大量查阅国内外相关的文献和资料,对整个设计有一个宏观的把握,并学习这些文献中的研究方法,为本课题的展开积累理论依据;第二步,精选一些英文文献进行翻译,对国外相关研究有一定的了解,扩展视野;第三步,开题;第四步,首先利用热平衡方程、烟气和导热油的进、出口温度以及标况下的流量等原始参数,计算出传热量,查阅和选取合适的导热油型号;第五步,在选取了翅片管的规格及其结构参数之后,计算出总传热系数,以确定螺旋翅片管的纵深管排数;第六步,在热力设计计算以及结构设计计算完成之后,进行阻力计算以及强度校核计算,保证所设计的螺旋翅片管式油加热器能够安全运行。最后,在烟气的流动压力降以及导热油管程压力降等各项指标满足设计要求的前提下,综合考虑各种因素,选择合理适用的结构设计、经济的结构形式,同时满足制造、检修、装配、运输和维修等要求,设计并绘制出该翅片管式油加热器的总装图以及壳体、框架、上下接口、翅片管和孔板等主要的零部件图。
在计算过程中,计算导热油出口温度的问题上,采用先假设再校核的研究方法,在校核温差合理时确定导热油的出口温度。在计算加热器迎风面管排数时,首先要保证导热油的流速不得低于0.5m/s,流速过低时则需要进行折流来保证流速;在制图过程中,综合考率了各个部件之间的尺寸配合,以及安装的可行性,保证油加热器制造的合理性。在技术方面,考虑了低温烟气的腐蚀等问题。在设计制造时,按照压力容器的相关标准,同时满足换热器相关标准。
本课题所设计的螺旋翅片管式油加热器进一步对紧凑式换热器的研究进行了总结和创新。在理论上,丰富了与翅片管换热器相关的研究课题,在实践中,因为其结构紧凑,体型比一般列管式换热器小,所以安装更方便,而且节省成本,增加了经济效益。
关键词:翅片管换热器 节能减排 导热油锅炉 余热回收
Design of spiral finned tubular oil heater with low dust flue gas
Abstract
In recent years, the problem of air pollution and fossil energy depletion has become an unavoidable topic of daily life. Thus, researchers in various fields are also focused on this, and the key to such problems is how to stop the deterioration of the environment and improve energy efficiency, which led to the world's most important topic - energy conservation and emission reduction.
At present, some thermal oil boiler due to high exhaust gas temperature, heat waste is large, the furnace thermal efficiency is low, the general thermal oil boiler outlet flue gas temperature about 300 ℃, and thermal oil boiler thermal efficiency is low. This project combined with the national policy of energy conservation and emission reduction, along the combination of scientific research and production principles, the use of waste heat to produce boiler water supply, improve the system thermal efficiency.
The purpose of this paper is to design a spiral finned tube oil heater to improve the thermal efficiency of the thermal oil boiler. Throughout the design process, the work is divided into several stages, and then gradually. The first step, a lot of access to relevant literature and information at home and abroad, the entire design has a macro grasp, and learn the literature of these research methods for the subject of the accumulation of theoretical basis. The second step, selected some of the English literature to translate to understand the relevant foreign research, and expand my vision; The third step, opening report. The fourth step is to use the heat balance equation, the inlet and outlet temperature of the flue gas and the heat transfer oil, and the flow rate under the standard condition to calculate the heat transfer quantity, and check and select the appropriate heat transfer oil model. In the fifth step, after selecting the specifications of the finned tube and its structural parameters, the total heat transfer coefficient is calculated to determine the number of deep pipe rows of the spiral finned tube; The sixth step, after the calculation of thermal design and structural design calculation is completed, the resistance calculation and strength check calculation to ensure that the design of the spiral finned tube oil heater can run safely. Finally, the flow pressure drop of the flue gas and the pressure drop of the heat conduction oil pipe meet the design requirements. Under the premise of considering the various factors, choose the reasonable structure design and economic structure, and meet the requirements of manufacturing, maintenance and assembly , Transport and maintenance requirements, design and draw the finned tube oil heater assembly drawings and shell, frame, upper and lower interfaces, finned tube and orifice and other major parts and components map.
In the calculation process, the first test method is used to calculate the heat transfer oil outlet temperature, after checking the temperature difference is reasonable, then determine the heat transfer oil outlet temperature. In the calculation of the heater side of the wind pipe row, the first to ensure that the flow rate of heat transfer oil shall not be less than 0.5m / s, the flow rate is too low when the need to bend to ensure the flow rate; In the process of drawing, the comprehensive assessment of the size of the various components with the installation, and the feasibility of the installation to ensure the rationality of oil heater manufacturing. In terms of technology, taking into account the corrosion of low temperature flue and other issues. In the design and manufacture, in accordance with the relevant standards of pressure vessels, while meeting the relevant heat exchanger standards.
The spiral finned tube oil heater designed in this paper has further summarized and innovated the research of compact heat exchanger. In theory, it is rich in research topics related to finned tube heat exchangers. In practice, because of its compact structure, the size is smaller than that of the general tube heat exchangers, so the installation is more convenient and cost effective.
Key Words: Finned tube heat exchanger; energy saving; Heat conduction oil boiler; Waste heat recovery
目 录
摘要………………………………………………………………………………Ⅰ
ABSTRACT………………………………………………………………………Ⅲ
第一章 绪论………………………………………………………………………1
1.1 课题背景……………………………………………………………………1
1.2 换热器的国内外研究现状…………………………………………………2
1.3 翅片管式换热器……………………………………………………………2
1.3.1 翅片管………………………………………………………………2
1.3.2 翅片管的结构参数…………………………………………………3
1.3.3 翅片管管束的排列…………………………………………………3
1.3.4 翅片管的换热性能…………………………………………………4
1.3.5 螺旋翅片管式换热器………………………………………………4
1.4 导热油在换热器中的应用…………………………………………………5
1.4.1 导热油的特点………………………………………………………5
1.4.2 导热油加热的优点…………………………………………………6
1.4.3 导热油系统…………………………………………………………6