References

How to reduce the operational costs related to blasting operations in closed tanks?
20.07.2017

How to reduce the operational costs related to blasting operations in closed tanks?

A feasibility study conducted in USA revels that even if traditionally all shipyards tend to use mineral abrasives for surface treatment operations, the new regulations related to environmental policies and improvement of working conditions, forced the navy industry to look for more efficient and less invasive solutions.

The study highlights the direct impact of mineral abrasives and metallic ones on the overall operational cost of a shipyard.

To be more specific:

  • The costs implied by the use of metallic abrasives (including the acquisition cost, the labor costs and the stocking costs for wasted materials resulted during the blasting process) are 50% lower than in case of using mineral abrasives
  • The labor costs related to the blasting operations and the abrasive cleaning ones are 60% lower than in case of using mineral abrasives
  • The most relevant savings generated by the use of metallic abrasives refer to the acquisition cost (1/10 of the cost implied by the use of mineral abrasive considering that we refer to the quantity of material which is necessary for treating the same surface one can treat during the whole lifetime of the chosen metallic abrasive) and to the stocking cost for waste material (2% of the one implied by the use of mineral abrasive).
  • The only relevant cost in case of working with mineral abrasive is the one related to its acquisition and it represents a third of all operational costs related to the blasting process
  • The only relevant cost implied by using metallic abrasives is the one for operating and maintaining the abrasive recovery system. This one represents almost half of the total operational cost
TypeCooper SlagGarnetProfilium StandardCast Iron
Bulk weight (kg/m3)1700-20002400-26003500-40003500-4000
Hardness>7-8 Mhos7-8 Mhos>64 HRc>60 HRc
 >54 HRc>54 HRc  
Size0.25 – 1.5 mm0.25 – 1.5 mm0.2 – 0.7 mm0.4 – 0.85 mm
 0.25 – 2.5 mm   
 1.00 – 2.8 mm   
Efficiency12 m2/h16 m2/h20 m2/h20 m2/h
Lifetime 1 – 2 (max 4)max 5200100
Consumption (Sa 2.5)50 kg/m28 kg/m20.5 kg/m21 kg/m2
Priece per ton(EUR)75300670440
Abrasive cost(EUR/m2)3.752.400.340.44
Ferrous contaminationNoNoYesYes