Sonic fog dust supression
It always looks good as the larger dust visible dust is quickly knocked out of the air stream, which immediately wins over the process guys at a demonstration, but be aware of such miracle cures for dust problems for “The devil lies within the fine print” as it were.
The following problems are present in all such systems;
Unless the water is super clean any dust ,organic bacteria and chemical content is atomised and becomes a respirable hazard. ( The human lung is the most sensitive of all our bodily intakes) .
Any dust induced anywhere near the energy zone of the nozzles is also instantly atomised as well thus increasing the content of the dust respirable content and not reducing it which is the primary objective here as health is more important than how an area looks.
The nozzles are destroyed at an alarming rate as well even in the hardest material and respirable metal fragments are also now introduced into the air body as a further toxic agent.
Visually the largest dust particulate is suppressed quite well and one can see an immediate difference in and area.
Wind has a major effect and can simply blow the fog away before it has any chance of collecting any dust and so there is a need for larger enclosures to permit the fog to saturate the contents of the enclosures.
In almost any plant situation the generation of dust is a dynamic process and the dust is being created continuously at a rate greater than one can retain in a fixed enclosure and so the leakage is also continuous. If one is to look at a dust extraction installation then to save on wastage of air extraction one needs to enclose the chute or head end of conveyors adequately to allow the same dwell time as spoken about above, but the essential difference is that because an extraction system is extracting from the enclosure continuously there is no outward leaks as the dust being pumped into the enclosure as a volume is extracted continuously at the same volume if all your calculations are correct and your reading of the plant dynamics and the same for the material being handled are correct.
The actual real use of sonic fog is to humidify and in that regard is extensively efficient with an application mainly cooling stacks and any stack emissions to comply with environmental legislation. Ironically it is in a stack where one actually achieves a better suppression as the atmosphere up there is well away from any place where the fine particulates one is creating can cause an exposure problem.
Author: Gerry F. Kuhn
- Single Bucket DustWatch unit