DOC《南京林业大学》

南京林业大学 本科毕业设计(论文) 题目: 机制木炭生产温度控制系统的研究 学院: 木材工业学院 专业: 热能与动力工程 学号:

080403212 姓名: 蒋明铭 指导老师: 梅玉春 职称: 副教授 2012年5月5日摘要就目前而言,我国森林资源严重不足,随着社会的发展,对于木材及其附属能源产品的需求也越来越多,长期以来人们对于森林资源的过度开采利用造成了人与自然的不平衡.

随着人们对生活要求的不断提高,环保节能意识也逐渐在人们脑海中形成.近些年,人们对于能源有效利用的关注程度和要求越来越高,因而推动了我国新能源、节能行业的发展.机制木炭作为一种新型的能源利用方式逐渐兴起并不断发展,在我国形成了一定的生产规模.然而,目前我国的机制木炭加工行业大多数为中小企业,且技术设备相对落后,自动化程度较低,这也导致我们的产品与其他发达国家相比,存有很大的劣势与不足. 在整个机制木炭加工过程中,对于温度的控制显得尤为重要.机制木炭大体分为干燥、制棒、炭化三个过程,每一个过程都对温度有着严格的要求.我国机制木炭行业中对于温度的检测与实时控制这块技术还不是很成熟,自动化程度不高,这也是我国机制木炭发展没有国外好的主要原因.出棒机是机制木炭主要设备之一,它对材料的挤压软化温度控制要求很高.我要设计的,就是将出棒机挤压软化温度控制在一定的范围.通过温度传感器,采集温度信号,然后反馈到控制系统中,然后PLC控制系统通过温度信号与设定值的对比,自动控制电加热丝的启停,从而使温度控制在一定的范围内变化.这种自动控制方式,一方面可以带来良好的经济效益,避免人工操作控制所带来的误差,保证了炭棒的成型质量与较高的生产效率,减少原料损耗.另一方面也带来良好的社会效益,用程序自动来代替人工操作,降低劳动力. 当然,这种设计也存在着一定的不足之处,首先一点不足是由机器设备带来的,比如说温度探头测温到反馈需要一定时间,这会引起一定误差,当然这无法避免.另外一点,所谓的温度自动控制也只是将温度变化控制在一定范围内上下波动,并不能精准的控制在某一个温度点上,这点还需要改进. 关键词:机制木炭、生产温度、PLC控制,可编程终端、实时监控 Abstract For the present, our country forest resources severity shortage, along with the development of society, for the wood and affiliated energy products demand more and more, people have long to forest resources of excessive exploitation caused the people and the natural imbalance. As people life request to improve the environmental protection and energy saving consciousness are gradually people formed in the mind. In recent years, people to energy and effective use of degree of concern and demand more and more high, thus promote the our country in the new energy, the development of the industry. Mechanism of charcoal as a new energy utilization way gradually arisen and development, in our country formed some production scale. However, China'

s mechanism charcoal processing industry for most small and medium-sized enterprises, and technical equipment is relatively backward, automation degree is low, it is also leading to our products and other developed countries, there is a lot of disadvantages and shortcomings. The mechanism of charcoal in the machining process, for the control of the temperature is particularly important. Mechanism of charcoal roughly divided into dry, the rods, carbonized three process, each process of temperature has strict requirements. Our country mechanism for the temperature in the industry charcoal detection and real-time control this technology is not mature yet, automation degree is not high, this is our country without foreign good development mechanism charcoal main reason. A great machine is one of the main equipment of charcoal mechanism, it to material extrusion softening temperature control requirements is very high. I want to design, is a great machine will squeeze softening temperature control in a certain range. Through the temperature sensor, collect the temperature signal, and then back to the control system, and then PLC control system through the temperature signal and setting the contrast, the automatic control electric heating silk rev. Stop, so that the temperature control in a certain range of change. The automatic control method, on the one hand, can bring good economic benefits, avoid artificial operation control brought about by the error, and to ensure the quality of the great molding with carbon high production efficiency, reduce raw material loss. On the other hand has also brought good social benefits, with the program to be automatic instead of manual operation ,reduce the labor force. Of course, this design also has certain deficiencies, first a little shortage is brought by machine equipment, for example, temperature probe temperature measurement to feedback need certain time, it will cause a certain error, which, of course, can'