DOC《南京林业大学》

南京林业大学 本科毕业设计(论文) 题目: 木材干燥温湿度控制系统的研究 学院: 木材工业学院 专业: 热能与动力工程 学号:

080403211 姓名: 黄赛冬 指导老师: 梅玉春 职称: 副教授 2012年5月7日摘要近几年来,由于环保、能源节约的要求以及木材科学的快速发展,使得在中国从事木材加工、地板生产以及一系列与木材相关的企业行业不断的兴起,中国木材行业呈现出欣欣向荣的景象.

但是同样的也存在着一些不能忽略的问题:当前社会要求企业节能减排和保护环境.但是目前大多数企业都是中小型企业,其在节能减排方面展现出来的效果不尽人意,存在着改进的必要;

另外节约劳动力成本,提高自动化程度作也是企业当前的一大发展趋势,但是大多数中小型企业的自动化程度还不高,生产成本居高不下. 结合这两方面的要求,对于木材加工行业都需要经行的一个环节―木材干燥,我们着重进行了改造.利用可编程序控制系统―PLC,选择合适的检测仪器.在干燥过程中实时监测温度和湿度,一旦发生变化及时自动的调整加热强度和排气量,使得干燥的温湿度始终维持在要求范围之内,从而干燥过程实现自动化工作.这样的精确控制使能源消耗量降低,而自动化的控制则大大节约了生产的成本,提高了木材加工产业的经济效益 在干燥加工过程中控制温湿度是两个不同的方面,两方面控制的同时进行使得控制程序相对复杂.此外温湿度只能反应干燥箱内空气的状况,并不能够精确反应木材的干燥情况.本课题中,尝试通过监测木材内部的含水率来控制干燥过程,使得控制干燥的效果更加显著. 关键词:木材干燥 、温湿度监测、PLC控制、可编程终端 Abstract In recent years,since requirement of the environmental protection and the saving use of energy and the booming development of wood science and technology,so many companies who are occupied in the production of wood or floor board are developed quickly ,the future of chinese wood industry is so beautiful and hopeful .However there are numbers of questions that we shouldn'

t ignore .Nowadays energy saving and emission reduction is the main direction in the industry of energy using and also fit the requirement of environment protection . But, the reality is a lot of companies are small and medium enterprise in energy conservation and emission reduction in this respect shown effect unsatisfactory, there is the need to improve. The current for save labor cost, automation work is also one of the enterprise the current development trend, but many small and medium enterprise automation level is not high, the production cost remains high. Combining the two requirements, For the wood processing trade needs done by a link-----dry wood, we focus on innovation. Use of programmable control system-----PLC . Choose the right test instrument, Real time monitoring in the process of drying temperature and humidity, Once the change in time, the intensity and the heating automatic adjustment emissions from automobiles, Make the temperature and humidity of the dry always maintain a requirement in scope, Thus the drying process automation work. Precise control, making energy consumption is reduced, and the automatic control, makes the production processing cost can save, which greatly improve the economic benefit of wood processing industry. In dry processing process, control temperature and humidity are two different aspects, Both need to complete the accurate control, makes the control program relatively complicated, The temperature and humidity of the air in the oven is only reaction the air condition, But lumber dry situation is not very accurate response, If can use monitoring the moisture content of timber internal, to control the drying process, So the results will be even more obvious. Key Words: Drying, PLC control, Programmable terminals, temperature and humidity monitoring 目录1前言