Design And Realization Of Temperature&Humidity Control System In Textile Plant

The i-d diagram was normally used in analysis and determining theparameter of air in domestic textile plant in the past, then one canmechanically adjust the air volume according to the unit parameters in orderto achieve the purpose of air conditioning, it is not only a low precisionadjustment and lag way, but also with operation limitations. Along with therapid development of the textile processing, the high quality of productsdemands increase, operating requirements to improve the workingenvironment of workers, site air stability requirements increasing, and airconditioning’s configuration becoming more complex, traditional manualcontrol system in textile air conditioning can’t meet the productionrequirements.This thesis is based on this background, the textile mill’s temperatureand humidity is the research object, to combine the HVAC basic theory andthe automatic adjustment of knowledge, meanwhile a real case of a textilemill， using wet-screen technology and configured with automatic control,is applied to explore and realize a successful automatically control in the fieldof temperature and humidity in the textile mills and reach precise controleffect. The main air conditioning energy consumption in textile plant is water,electricity, steam. In order to increase enterprise efficiency and reduceproduction cost, the most important task for HVAC engineer is to use andsave energy reasonable.Normally the air conditioning treatment is inclusive heating, cooling,humidifying, dehumidifying and air mixing. The wet-screen technical whichwas focused described in this thesis is humidifying and cooling in equal enthalpy process, following the evaporative cooling principle. Wet-screen airconditioning system is traditional air conditioning equipment, with a longhistory, mature technology and the application is simple. But it can be onlyused in low level air conditioning field because of its own defect at present.This thesis brings PLC technology application into wet-screen airconditioning system control field, help to overcome the limitation of thewet-screen air conditioning application, promote its application space.A textile mill, who will establish a new twisting and doubling plant, willbe the real case as the wet-screen air conditioning application. The airconditioning auxiliary room "H" type structure is set up according to theworkshop building structure, which can isolate the important load area andthe no-important area, at the same time the air conditioning area and thenon-air conditioning area are also isolated."H" type area in the middle of theauxiliary room zone also divide important area into two exactly same piecesof area, It’s helpful for air uniform distribution, not only playing a crucial rolein the temperature and humidity stable control, but also reaching the purposeof saving energy.This thesis focuses on the control side, making reasonable program,optimize the air conditioning operation energy using and saving. Basing onthe reasonable arrangement of air conditioning system room, the wet-screenair conditioning equipment will be reasonable controlled. Hollysys LK serieslarge PLC is chosen as the controller, with Powerpro platform for softwareprogramming, the system is divided into winter, summer two operation mode,the enthalpy value can be calculated by program automatically, the sequencecontrol is applied into the actuator unit, the workshop temperature, humiditywill be separately accuracy controlled.The final operating data records can prove that this thesis about textileplant temperature and humidity control system design is very successful.