Experimental study of the seawater fouling on a plate-frame heat exchanger for utilization of waste heat from powerplant

摘要

The overall heat transfer coefficient, pressure drop, and the fouling thermal resistance were compared between a clean and a seawater-exposed, fouled plate-frame heat exchanger. The fouled heat exchanger was utilized for heat recovery from the seawater-effluent for 3 months at a powerplant site. The performance tests were conducted at temperatures of 20 degrees C and 30 degrees C on the fouled-side, while the corresponding temperatures on the clean-side were 15 degrees C and 25 degrees C, respectively. Flow rate ranged from 20 to 40 l.min(-1) on the fouled-side and the clean-side of the heat exchanger. In the absence of fouling, the average U value was higher than that under the fouling condition by 21.3 %. The average thermal resistance ranged from 0.135 m(2).K.kW(-1) to 0.157 m(2).K.kW(-1). The pressure drop was less than 2 kPa with the change of temperature, but the pressure drop of the fouled-side increased by 400 % compared with that of the clean-side.