Mobile fumigator disinfects with formaldehyde - automatically followed by release of neutralising ammonia gas

摘要

Mobile fumigation unit, for disinfecting premises with heat-generated formaldehyde, comprises two, independently-wired, electric resistance heaters, one serving a generator of formaldehyde and the other serving a generator of gaseous ammonia, and an automatic programming device which controls the two electric heater circuits. Pref. a motorised fan. also controlled by the programming device, is mounted above the two generators in the fumigation unit, and should have a delivery capable of 10 atmos. changes/hr of the premises. The programmed controller should provide a fumigation sequence comprising: release of formaldehyde with fan circulation; formaldehyde heater off but fan on for several hrs, release of ammonia gas; and ammonia heater off but fan on until the formaldehyde is fully neutralised by ammonia. Used for fumigating premises with formaldehyde followed by release of ammonia gas which neutralises the ammonia by forming hexamethylenetetramine. The complete cycle of disinfection and neutralisation is carried out automatically without an operator having to enter the premises to set off ammonia generation while formaldehyde fumes remain. The premises are fit for use much sooner when neutralised in this way.