De-ionized cooling water system study and improvement at TLS

In order to promote the stability and quality of the de-ionized cooling water (DIW) system, a series of studies and improvements on the DIW system are accomplished at the Taiwan Light Source (TLS). The total DIW system capacity is increased 400 GPM, where a special subsystem of 150 GPM is for a new superconducting-rf (SRF) system only. The DIW temperature is globally controlled within ± 0.1 °C. A high precision temperature control system of ± 0.01 °C for local DIW supply is also established to meet the critical stability requirements. The water quality has also been improved by upgrading local filters, reverse osmosis, conductivity meters, pH monitors, flow meters and various resins. The conductivity of the water has been maintained above 10 M ohm/cm and the pH at 7 ± 0.3. Additionally, the dissolution of oxygen, which is another essential water quality factor, has also been much reduced from 5000 ppb to 6 ppb by new deoxygenating equipment.