| DE-GASSING
|
Hydrogen is always generated during electrochlorination and is directly proportional to the amount of generated chlorine. Hydrogen is an inert by-product and does not participate in the overall chemical reaction. It is discharged along with the hypo into the de-gassing tank where it will disengage. This is the primary function of the hypo de-gassing tank. Hydrogen is then safely diluted and removed with blower air from blower fans. There are usually 2x 100% blower fans, a duty and standby fan.
In order to ensure 100% safety, hydrogen is diluted 4 times below the LEL (lower explosion limit) of H2. A failsafe operation is also employed where dilution air is continuously measured with an air flow sensor and, only after the set flow rate is achieved, is a signal send to the control panel to enable the electrochlorination process. Any dilution air low-flow condition will activate a system emergency shut down.
The second purpose of the hypo de-gassing tank is to act as a retention tank for the dosing system to offer a steady supply of hypo and to prevent pump dry-running.
The third purpose of the hypo de-gassing tank is to control the start/stop of the hypo generation process. During hypo dosing the hypo level will drop and as it reaches the low level (LSL) the electrochlorination process will start and the hypo de-gassing tank will refill again. As the level reaches the high level (LSH), hypo generation will stop.
Hypo dosing and hypo generation are therefore two completely independent processes that are only interphased with the hypo tank’s low and high level switches
|
|
|
