Corr-ZeTM Products to Eliminate Residual Dust Contamination and Improve Surface Cleanliness After Dry Blasting with Copper Slag

The intention of this field trial was to reduce residual dust contamination and improve surface cleanliness after blasting with copper slag.

Using ‘copper slag’ to blast clean a test panel the blaster intentionally adopted a technique which would maximise both blast media particle embedment and residual dust contamination.

Using the method ‘Elcometer 142 Dust Assessment in Accordance with ISO 8502-3’ we tested for residual dust contamination.

As expected, the results were terrible:

  • Test 1: Dust Quantity was 5 (the highest on the scale of 1-5) and the dust particles assessed as class 4 (between from 0.5mm to 2.5mm, the second highest on the scale)
  • Test 2: Dust Quantity was 4 and the dust particles assessed as class 4

The blasted surface was visually assessed as achieving Commercial Blast (SA 2, NACE 3/ SSPC-SP 6), as there was a great deal of staining evident. This is likely because the Copper Slag was very coarse and the particles were unable to clean out the crevices, leaving a high level of staining.

The test panel was then high pressure washed at 3000psi with 1% Corr-Ze™100 additive.

The surface cleanliness standard improved, and was visually assessed as achieving Near White Metal (SA 2-1/2, NACE 2/ SSPC-SP 10), as there was still staining evident, but better than before.

The big difference was that the water blasting almost completely eliminated all residual dust contamination:

  • Test 3: Dust Quantity was 1 (the lowest on the scale of 1-5) and the dust particles assessed as class 0 (not visible under 10x magnification)
  • Test 4: Dust Quantity was 1 and the dust particles assessed as class 1 (visible under 10x magnification, but not visible to the naked eye)

As a final test, Corr-Ze™200 was applied to a small zone at the bottom left of the test panel to see if the staining could be removed.

Corr-Ze™200 did in fact remove all the residual staining, and was visually assessed as achieving White Metal Blast (SA 3, NACE 1/ SSPC-SP 5).

In Conclusion:

  1. Using high pressure washing with 1% Corr-Ze™100 will very effectively eliminate residual dust contamination without creating another problem of premature flash rust. In this test, we almost completely removed all traces of residual dust contamination.
  2. Furthermore, application of Corr-ZE™200 was very effective in cleaning out residual staining left in crevices after blasting with Copper Slag, leaving a White Metal (SA 3) surface standard.