Coal slag VS Aluminum Oxide for Sandblasting

Coal Slag and Aluminum Oxide are two of the most common sandblast medias companies use for preparation of a products surface. Both medias have pros and cons and today will give an overview of their benefits, when they are ideal, and important considerations when thinking about choosing one or the other.

Coal Slag

Pros

• Coal Slag is one of the most affordable of disposable sandblast media costing approximately 25 cents per cycle (a cycle referring to using an entire ton of media and assuming no reuse which is normal for black beauty)
• Coal Slag is one of the most readily available blast medias in most areas
• It is ideal for removing medium – Heavy amounts of paint and for prepping surfaces for coating application for a profile range of 2- 6 Mils depending on the coarseness of media used
• It turns to dust on impact which can help with clean up if reclamation is not important

Cons

• Does not have the cutting speed that Aluminum Oxide provides
• Will only provide a single life cycle
• Disposal costs can be higher due to having to use more media for the same surface

Ideal Applications

• Ideal for removal of mil scale, rust, and medium to heavy amounts of paint.  Ideal for single use applications. Great for target profiles of 2- 6 mils in depth.

Aluminum Oxide

Pros

• Offers some of the fastest cutting time of any abrasive reducing the amount of time to prepare a surface which improves production rates
• Reusable up to 6 times in certain situations and if used 6 times the cost of the media is about 9 cents per pound
• Can be recovered and reused helping save on media costs long term
• Can reduce costs by reducing media disposal costs
• Create less dust as media will not fracture on initial use
• Ideal for creating surface profile of 1-6 Mils deep and removing mil scale, rust, or medium to heavy paint
• Will not color the surface from blasting

Cons

• Higher initial costs running around 55 cents per pound and is higher cost than brown Aluminum oxide
• Can be harder on equipment from sandblast nozzles to blast rooms requiring additional equipment upgrades in certain scenarios to properly protect equipment from long term damage
• To be cost effective will want to consider recovery equipment for the blast media

Ideal Applications

• Ideal for blast recovery rooms where production is the primary goal and where hard to remove surface contaminants are present. Also ideal if concerned about dust creation in outdoor blasting process. Great for mil profiles of 1-6 Mils deep.

Notes: Cost per pound of media is based on purchase quantity of one ton and in the case of White Aluminum oxide the media being reused approximately 6 times prior to disposal. Disposal fees have not been considered in the example given and could increase the cost of black beauty. Pricing reflects costs in the Northeast Market and may vary based on market.