Analysis On The Water Network Of Petrochemical Industry

Water pinch technology (WPT), as a very effective optimization tool of analysis and design for the water network, developed from 1990's. The flux and the key factor of water reuse can be found by WPT, and then the minimization of water use can be realized through design the water network according to WPT. WPT can be used not only in the reconstruction but also in the design of new equipment. On overseas, lots of keys were reported on the application of WPT in the process industry, but the traditional water economization technologies were still used in China. Large amounts of fresh water were consumed by petrochemical industry; simultaneously great deals of wastewater were discharged. 5 to 6 times more fresh water was used than in the developed countries for process every ton crude oil in China, so it's necessary to ameliorate the present equipment.As a part of the project "Research of test and application of eco-industry in the petrochemical industry in shanghai", the optimization of water network of some petrochemical industry was researched by WPT. According to the theory of WPT, "Decision Tree", a more appropriate method for multi-contaminants and multi-operations water network, was brought forward. At the same time, the corresponding computer program was written by the MATLAB language to save manpower. In practice, firstly, investigation and collection data for the water and discharge of the oil refining department of the petrochemical industry were carried out. And then the feasibility and limiting conditions of equipments were discussed. Finally, "Decision Tree" technology was utilized to determine the minimum of fresh water, the flux and concentration of reuse water and the designed water network was optimized. Through WPT optimization, 20% fresh water was saved and the cost of reconstruction was reduced.The research indicated that "Decision Tree" technology can be used to the design and reconstruction of the petrochemical industry water network, at the same time, it provided profitable suggestion for other industries.