Dolomite powder

I am doing a project on the gas cleaning system. We are using the Dolomite powder for the cleaning the gas. I have some issues about the dolomite powder which should be studied before proceeding for experimental work. 1. Availability and cost of the dolomite in different countries like china, African countries and American countries.
2. Use of the dolomite disposal. The powder is used to absorb the some particulate matters and Tar. So the disposal of the tar laden powder is the big issue.
So, Can u provide me some information that where can be this west powder used.