Discuss Rick Barnett's answer to: How do you make diesel exaust fluid

Big industrial diesels have smoke towers.  They don't burn regular diesel fuel.  They burn straight petroleum.  They put up a smoke stack a good 175 feet off the ground and fill it with high temperature foam "stars."  They look a little like jacks you played with as a kid.  They are made of ceramic and have pressurized CO2 inside them.  Tou'd have a rough time trying to break them with a sledge.

They run the exhaust into the stack about a quarter of the way up and let  goo form on the stars.  As the stars warm up a thick tar flows down into a catch basin and then they put that into moulds.  It hardens in an hour or two and they sell that to make roads.

Coal fired powerplants do pretty much the same thing. 

Either one uses a fine water spray in a secondary tower to settle out the ashes and that is gray to white and it goes into concrete. 

They don't waste the CO2 either.  They liquefy it by chilling it down and then they put that in refrigerated tankers and shoot that into oil wells.  It pushes out more oil and keeps the CO2 out of the air.