Research On Optimization And Application Of Water Network System For Petrochemical Enterprises

Along with the continually accelerating pace of industrialization and the increasing demand in industrial water,the safe and effective supply of water resources become the key to economic and social development.Petrochemical enterprises are both large fresh water consumers and large waste water dischargers.However,there is still a big gap in water efficiency between petrochemical industries in China and the advanced petrochemical industry in the world.Thus the potential of the water-saving in China is enormous.To determine the weak link of water use,to tap the water-saving potential of water network and to approach zero liquid discharge through petrochemical enterprises’ supply-water and carrying sewage water balance test becomes the petrochemical enterprises’ target of water usage.The paper introduces the research status of water network system at domestic and abroad.With the goal of minimizing the volume of water consumption and wastewater discharge,the combination of water pinch analysis and mathematical programming are used to optimize the water network through the analysis of the optimization technology of water network system.The process water link is selected as the most potential water-saving unit after finishing petrochemical enterprises’ supply-water and carrying sewage water balance test and mapping water balance diagram of enterprises.Through the comparison of characteristics of water network stepwise design and water network of simultaneous design,the paper chooses the water network stepwise design as the designing way in this system.The catalytic reforming,atmospheric and vacuum distillation unit,coking unit,hydro-refining unit and catalytic cracking unit are selected as optimizing objects.Water pinch analysis plus mathematical programming,stepwise design method,were employed to optimize designing.The result shows that the minimum fresh water is 31.37 th and minimum discharge of wastewater is 36,58 t/h.Compared with the previous amount,fresh water consumption discharge of wastewater reduces by 42.9%and 33.4%,respectively,indicating the effect of water-saving is remarkable.To adapt the changes of the type of impurities and number of units in the calculation process,and to improve the efficiency of data processing,the algorithm program is compiled with the combination using of MATLAB and EXCLE,whose result is in accordance with the manual calculation.It has been the effective and simple support of technology for the optimization and transformation of petrochemical enterprises’ water system.