K-2
(Potassium Sulphate)
More commonly known as K-2, this is a fairly new blasting media
and it amounts to nothing more than potash garden fertilizer.
Advantages
K-2 has many of the advantages of baking soda in that it is environmentally
and worker friendly, is water soluble and is non sparking. Additionally,
K-2 is Ph neutral and is more aggressive in nature reducing the
amount of time required to strip the item. When compared to baking
soda, K-2 leaves an increased profile, leaves no residue, and
reduces stripping time and the amount of media used. Tests have
shown K-2 to be as fast as seventy grit silica sand without pitting
the metal underneath or any of the health concerns related to
silica sand.
Disposal
While water soluble, it is not recommended that K-2 be washed
away. It should be gathered up and disposed of in the local landfill.
If hazardous materials have been removed, appropriate disposal
techniques must be followed.
Disadvantages
Dry blasting creates dust that may have to be contained. While
considered non-hazardous, K-2 will irritate the skin and eyes
and requires the use of additional personal protective equipment.
Ingestion of large quantities have also shown to irritate the
digestive tract. As it is similar in nature to fertilizer, large
quantities left on the ground will damage vegetation proper
cleanup and disposal techniques are necessary. K-2 is not suited
for use on softer substrates such as fiberglass.