Application Study on An Electrolytic Softening Reactor for The Removal of Calcium Hardness in Cooling Tower Water Systems

摘要

An electrolytic softening reactor was developed through fluid dynamic modeling and scale removal performance tests in the KEPRI laboratory. The reactor system consists of anode (iridium coated titanium mesh), cathode (stainless steel reactor), and a DC power supply. The alkaline environment of the cathode surface induces the deposition of calcium ion in the form of CaCO_3 and the calcium ion is removed from the cooling tower water system. A synthetic water was prepared to simulate the cooling water quality of a domestic power plant. The fouling resistance, measured from a fouling monitor, was 4. 4x10 ~-(4) m~2-°C/W in the test conditions of LSI 2. 3, velocity 1. 9 m/sec, and heat flux 110 kW/m~2. When the electrolytic softening reactor was applied, the fouling resistance decreased to 7. 7x10~(-5) m~2-°C/W in the same test conditions. This electrolytic softening reactor showed good scale inhibition performance in the high cycled cooling tower water system without any chemical addition.