Analysis and Optimization of Open Circulating Cooling Water System

Abstract

Open circulating cooling water system is widely used in process industry. For a system with a fixed structure, the water consumption and blowdown usually change with the varying parameters such as quality and temperature. With the purpose of water saving, it is very important to optimize the operation strategy of water systems. Considering the factors including evaporation, leakage, blowdown and heat transfer, the mass and energy conservation equations of water system are established. On this basis, the quality and temperature models of makeup and blowdown water are, respectively, developed. The water consumption and discharge profiles and the optimal operating strategy of the open recirculating cooling water system under different conditions are obtained. The concept of cycles of temperature is proposed to evaluate the temperature relationship of various parts of the open circulating cooling water system. A mathematical relationship is established to analyze the influence of the water temperature on the makeup water rate of the system under the condition of insufficient cooling capacity of the cooling tower. In addition, the co-influences of quality and temperature parameters on the system are analyzed.