Soda blasting uses sodium bicarbonate, similar to baking soda, but with a larger particle
Sodium bicarbonate has a pH of 8.4 and can be disposed of in most wastewater treatment systems. It can be neutralized by either a vinegar/water solution, or just
water dilution (it dissolves completely and quickly in water).
There are a variety of alternative blasting medias : Crushed or Beaded Glass, Corn Cob, and Walnut Shell come to mind.
Others include:
Ice, Wheat Starch,
Aluminum Oxide, Plastics (Urea,
Acrylic, Polyester, and Melamine), Pumice, Silicon Carbide,
The only material that needs to be disposed of are the coatings removed, which can be separated by dissolving the blast media in
water and the use of a filter or centrifuge to separate the coatings from the now dissolved soda.