Giant Vacuum Cyclone?

[v-600]

Treat this like a hypothetical scenario, unless you're a wealthy industrial philanthropist. I was just wondering about this after watching a lorry spewing black clouds of diesel exhaust, and going for a dusty bike ride, but how good are cyclone vacuum systems?

In Kathmandu there is a pollution problem as most of it just hangs over the city, trapped by the valley walls. Could you just use industrial size cyclones to filter the air? I'm sure the collected dust etc could be used for something (making breeze blocks springs to mind), or worst case just buried.

Ktm valley is approx 570 square km, or allowing for an average valley wall height of 400m, 228 cubic kilometers.

I guess with something like this you wouldn't be after a strong vacuum, but would need huge amounts of air flow, but at the mo its late, I'm tired and can't think where to begin. Power could be solar, or hydro to avoid adding any more air pollution, but could either of those provide enough to cycle 228km3 of air at an acceptable rate?

Thoughts?

 

[Howard]

Depends on the particle size of the dust.

 

[lakedude]

Better to pollute less rather than clean up after using even more energy and creating even more pollution...

 

[lakedude]

http://en.wikipedia.org/wiki/Diesel_particulate_filter

 

[v-600]

In an ideal world less pollution would be great. However maintainance/road worthiness isn't one of the high points for Nepali lorry owners. Also added in is the fact that there is a lot of road building/expansion happening that is throwing dust into the air which particle filters wouldn't catch.

 

[CycloWizard]

Once it's out in the air, there's no remotely economical way to recollect it. In a laboratory setting, you can use charged plates to attract aerosols but the electric fields required to achieve good collection are fairly large. Since electric field drops off rather quickly with distance from the plate, this is only a useful approach at small length scales (a few millimeters).