A fouling mitigation device for a wastewater heat recovery heat pump system using a bubbling fluidized bed with cleaning sponge balls

Title & Authors
A fouling mitigation device for a wastewater heat recovery heat pump system using a bubbling fluidized bed with cleaning sponge balls
Kim, Jong-Soo; Kim, Do-Bin; Kim, Jun-Ha;

Abstract
Wastewater heat recovery heat pump systems use heated wastewater from public baths or factories as the heat pump`s heat source. Generally, this system uses a bare tube evaporator. In the heat transfer process from wastewater to refrigerant, thermal resistance is caused primarily by fouling deposits on the outside surface of tube. Fouling directly increases thermal resistance and decreases heat pump efficiency. Thus, it is desirable to eliminate fouling. In this study, we fabricated a fouling mitigation device using a bubbling fluidized bed with cleaning sponge balls in the wastewater bath. Experimental conditions were as follows: $\small{20^{\circ}C}$ cold-water temperature, $\small{40^{\circ}C}$ wastewater temperature, 100 L/h cold water flow rate, and $\small{0.161m^2}$ heat exchanger surface area. Experimental results showed that the thermal resistance of fouling decreased by 56% with the fluidized bed alone and by 86% with both the fluidized bed and cleaning sponge balls.
Keywords
Wastewater heat recovery heat pump;Fouling mitigation device;Cleaning sponge ball;Bubble fluidized bed;
Language
Korean
Cited by
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