Design and development of heat exchanger for treated tank water and cool waste water : the case study of the frozen shrimp production line

Abstract

The research objective is to utilize the waste water at 12ºC to 20ºC in exchange with the process water at the temperature of 29ºC. After entering the heat exchanger, the process water will have the reduced temperature of 19ºC and then will be delivered to the cooler so the temperature of the process water will further be reduced to 15ºC to involve in the production process. Consequently, the cooler’s energy use is lower. Since the common coolers used in these days have problems about the clogged system caused by shrimp residue, the cleanup of the system is difficult and the maintenance cost is high. With this problem, the research and development of the new heat exchanger is carried out, resulting to the Shell and Tube Heat Exchanger type with the angled lid and the waste water flow control pads allowing the water alternatingly running through the lower part and upper part of each pad. The process water will flow in the 6 sets of the stainless tubes with 2 mm. thickness, ½ inch diameter and 6 meter length. The space between the set is 5 centimeters for exchanging heat with the waste water flowing outside the tubes. The study conclusion is that the new heat exchanger can reduce the temperature of the process water to 19ºC so it can save the electricity cost of the cooler for 886,485 baht per year and make the cleanup easier without taking off the equipment parts, thus lowering the maintenance cost as well.