Develpment And Engineering Practice Of Energy-Saving Control Technology In Chlor-alkali Production

Chlor alkali industry is not only a basic raw material industry of the national economy,but also a typical largepower consumption.The energy saving work of the chlor alkali industry in China is facing a grim situation.In this paper,the energy saving transformation of ion-exchange membrane electrolyzer and circulating water system are carried out for the key energy consumption device and actual energy conservation demand of a chlor alkali enterprise.The main contents are as follows:(1)In the background of energy conservation and emission reduction,the research status of energy-saving work of chemical enterprises is reviewed in detail,and summarized the status of energy saving technology in chlor alkali enterprises in technology,equipment update,device innovation etc.At the same time,the circulating water system and energy saving technology are carded and analysised according to the present situation.(2)As to the energyconsumption device-ion-exchange membrane electrolyzer of chlor alkali enterprises,starting from the principle of electrolysis and the specific process flow,analyses and sorts out the factors affecting the current efficiency,which focused on the cell voltage,the long distance between the membrane which leads to highcell voltage is found,thereby affect the current efficiency,and the comprehensive energy-saving technological transformation is carried out,which not only makes the membrane distance minimum,but other special treatment processing technology has been used to ensure that the ion-exchange membrane electrolyzer in the distance to reach the minimum at the same time,realizs the uniform distribution of multi pin spring diapHragm configurations and unit cell current protection to the electrolyzer,improves the electrode performance and current efficiency,effectively reduces the tank voltage and realizes the double drop of AC power consumption of caustic soda and the comprehensive energy consumption of ion-exchange membrane electrolyzer.Finally,according to the actual operating effect after reformation puts forward the management of technical parameters on the direction of optimization.(3)The actual energy demand for utility systems,focusing on the implementation of energy efficient transmission and distribution of circulating water system integration technology,Firstly it is based on the energy saving of the pump body,the operation control of parallel pumps was optimized;Secondly is the driving electric fan will transform the circulating water system for water turbine.The backwater system surplus energy cascade utilization;Thirdly the smart balance valve is using to solve the system network and terminal hydraulic imbalance problem;Fourthly is the integration of these three technologies,implement energy efficiency monitoring system as the production load demand of chlor alkali enterprises,sets up the whole process of circulating water hydraulic and thermal state monitoring,and achieve the efficient operation of the whole system.After the implementation of ion-exchange membrane electrolyzer membrane polardistance energy-saving technological transformation projects,the per unit power consumption reduces 47.875kWh/t,annual electricity reduces 6106000 kWh which equals standard coal equivalent 1953.92tce;After the implementation of energy efficient circulation water system distribution integration transformation,to achieve the goal of energy-saving 9507400 kWh/a,which equals standard coal equivalent of 3042.37tce.Chlor alkali industry is the main energy consumption of the key energy device industry,energy-saving technologies research not only has important practical significance,but also can provide an important reference for China's other chlor alkali production and chemical industry enterprises energy saving work.