Investigation On The Improvement Of The Drying Crafts And Arts Of Synthetic Leather-Making Process And Its Control Strategies

Currently, environmental pollution and energy consumption are the main factors which restrict the development of China’s synthetic leather industry. Aiming at the problem of environmental pollution, a kind of environment friendly ecological polyurethane synthetic leather was developed, which commendably solved the problem of the serious pollution in the process of synthetic leather production. In view of the energy consumption, our country is making great efforts to construct the Synthetic leather industrial park with CHP(combined heat and power), and The technology of reforming the production of synthetic leather by using steam central heating instead of distributed heat conduction oil boiler is put forward. The technology can save energy and emission reduction while avoiding the disadvantages of the heat conduction oil, such as poor safety, high operating cost and short service life. The paper was funded by the innovation team of energy saving and environmental protection key equipment and control engineering of light chemical industry (2014KCT-15). On the basis of construction of leather industrial park with CHP, the drying section which has high energy consumption in synthetic leather producing machine was selected as research object in this present work. The improvement scheme of synthetic leather drying process was put forward, and the control system of steam supply was designed, simultaneously, the drying energy consumption was further reduced, the drying efficiency and the drying quality were improved. The main works were as follows.I The drying process of traditional synthetic leather was studied and the feasibility of steam supply strategy was analyzed.With traditional synthetic leather drying section as the object of study, wet base drying and dry synthetic leather drying process were researched, and the shortcomings of heat-conducting oil heating system was pointed out. With the transformation technology of steam power plant instead of conducting oil in construction of leather industrial park with CHP, steam supply scheme of synthetic leather drying was proposed, and feasible analysis was carried out.II The drying process of synthetic leather based on steam supply is improved.Based on the steam supply scheme in the thermal power plant, the synthetic leather drying process was improved. The wet base drying device was improved to be the combination drying device with cylinder and oven, and a tandem steam supply system is designed. At the same time, the parallel steam supply system is designed on the basis of the oven drying device.III The control scheme of the improved synthetic leather dryer section was designed.Based on the study of improved wet base drying and dry synthetic leather drying process, for the key and difficult point for each stage control, the serial type steam supply control scheme and steam supply control scheme were presented. At the same time, according to the complex characteristics of the hot air temperature control of the outlet of the heat exchanger, the solution of Smith-Fuzzy PID feed forward feedback control is designed. By controlling the parameters of drying, the drying efficiency and quality are improved, and the energy consumption is reduced.IV The DCS control system for the synthetic leather dryer section was designed based on S7-300 PLC.According to the control scheme of the synthetic leather drying system, the DCS control system is built. The hardware based on S7-300PLC was designed, and the programs and the operation pictures were designed in the STEP 7 and WinCC, and the data transmission between MATLAB and PLC was completed through OPC technology. The DCS control system realizes the on-line control of the drying process.Currently, the country is making great efforts to implement the CHP production of the synthetic leather industrial park, which is used to replace the heat transfer oil with steam in the thermal power plant for the production of synthetic leather. Based on the implementation plans, the drying process of synthetic leather was improved, and the steam supply control system based on improved drying technology was designed. The effective recycling of steam in thermal power plant is realized, and the cost of drying is reduced, and the safety of synthetic leather production process is improved. The program conforms to our country policy of cogeneration energy saving, has a certain originality and generalization.