A Study on the Improvement of Thermal Efficiency of High-Temperature High-Pressure Washer Equipped with Exhaust Gas Waste Heat Recovery System

Abstract

A high-temperature high-pressure washer that saves thermal energy by drastically reducing exhaust gas temperatures by recovering the waste heat of exhaust gas at 270°C discharged through the flue duct after heating the cold water that flowed into the boiler was studied. In addition, by applying the devices developed in this study to the high temperature and high pressure pump that can be used for boiler devices at high temperatures, research results that can reduce the load of the boiler per se required due to the duranbility of pressure resistant boilers required for existing washers were derived. In addition, since the high-temperature high-pressure washer developed in this study is based on the exhaust gas waste heat energy recovery, the research results that drastically save energy with the technology that maximizes efficiency compared to existing technologies were derived. As a result of the study as such, the thermal efficiency of the washer that comprises an exhaust gas recycling system and a low pressure boiler was shown to be 20.5~21.2% higher than that of the washers comprising a high pressure boiler. In addition, the fuel saving rate of the washer that comprises an exhaust gas recycling system and a low pressure boiler was shown to be at least 20% higher than that of the washers comprising a high pressure boiler. Furthermore, since the thickness of the coil of the boiler was reduced, the thermal resistance was greatly reduced leading to improvement of thermal efficiency and great reductions in material costs and fabrication costs.  

Keywords – Washer, Waste Heat Recovery System, Exhaust Gas, Improvement of Thermal Efficiency, Low Pressure Boiler