NUCON Model HGP-H Pulse Mode Halide Generator
The NUCON F-1000-HGP-H is designed to inject a known amount of R-11, R-12, HCFC-123, HFC43-10, HFC134a or 1-Bromobutane liquid into the air system of Charcoal filtration systems. The total quantity of halide used is reduced and exposure of the charcoal to halide loading is minimized.
- Lab Fume Hoods/Exhausts
- Safety and Non-Safety Related Nuclear Air and Gas Treatment Systems
- High Efficiency Carbon (Charcoal) Air Filtration Systems
- Vapor Removal/Scavenger Systems
Testing of Gas Filtration Systems is often performed to meet bypass leakage requirements. Typically, a continuous injection of R-11, R-12, HFC43-10 or HFC134a is made for up to five minutes while inlet (upstream) and outlet (downstream) halide concentrations are monitored.
Steady injections of challenge halide, however, result in a "temporary" loading of halide on the charcoal filters being tested. Retesting following correction of bypass leakage defects must be delayed until adsorbed halide is purged (desorbed). This can be as long as 24 hours.
Under conditions of high humidity, breakthrough of challenge halide can occur so quickly that test data is suspect. Testing of thin (<1 inch) charcoal adsorber beds is equally difficult because of premature breakthrough.
Pulse Mode Testing
An alternate method for in-place leak testing has been developed. This technique involves injecting pulses of known amount of challenge halide while continuously monitoring upstream and downstream concentrations which are delayed by the charcoal. The advantage of injection of a known amount is that, if the airflow is known, the upstream concentration can be calculated and only the downstream reading is necessary. Pulse mode testing requires the injection of halide in controlled amounts as a series of repeatable small-quantity injections. As a result, less halide is used, retesting is easier and hard-to-test systems can be accurately tested.
The pulse mode testing method permits easy identification of leak locations.
The NUCON HGP-H Pulse Mode Generator consists of:
- Holding Chamber
- Pulse Valve and an optional spray nozzle
- Halide Reservoir
- Metering Valve