A recent installation at a marble quarry in Namibia of the Rubble Master RM 90GO! Impact Crusher has opened up a number of new alternative revenue streams for the owners. The client, initially, had a mobile Metso jaw and screen crusher, and were looking at various options to add more value to their operation by varying production output from the site. 

While well-entrenched in the market, with a product ranked in the top 1% quality-wise, there were two options to grow the business. They could either produce more marble, which was undesirable as that would compromise the lifespan of the quarry or they could use the waste materials that continuously piles up. A decision was made to utilise the waste materials.

Being a marble quarry, quality is paramount. Should any of the material be cracked, or have inherent flaws, it is deemed waste. This does not mean the material is useless and by crushing the waste they would be adding value and manufacturing a sellable product. This newly crushed waste material has a number of uses in the construction and industrial sectors from tile grout all the way to additives in commercial products – basically anywhere a fine powder is required.

“Initially, they were using the jaw crusher and screen to do single-stage crushing, but were achieving very low volumes,” explains Fernando Abelho, Africa sales manager at Pilot Crushtec. “The team from Pilot Crushtec spent about six months with them in order to understand their business. The Client did an exhaustive analysis in terms of what other industry uses there could be for their waste and what specifications were required to compete in the market, Pilot Crushtec was then consulted on how to achieve the required product specifications. Our initial idea was to just put in a single screening plant to drop operating costs as material was being double handled. Essentially, this meant the material was fed into the jaw crusher, split into three usable products and a fourth that was still too large to be of any use and had to be reprocessed. The extra screen, however, would not solve the problem as the client’s production rates were just too low and the cost could not be justified. The only logical solution was to increase production, and the Rubble Master was the perfect tool for the job.”

With the Rubble Master RM90GO! in place, there now exists a thorough two-stage crushing process.

To properly explain the mechanics of crushing Abelho likens the process to driving a car. “You need to go through all your gears to get to your top speed and it is the same when crushing. You have your first stage that will generally round off the material from 600mm to around 100mm. The second stage will then further reduce the size from 100mm down to about 25mm. You can, of course, abuse the various stages but this does come at a cost. Your efficiency will suffer, wear and tear will increase, and production levels will drop. The client has negated all of these negatives by installing the Rubble Master RM90GO! and their production has almost tripled. They are at a point  where they have to find more clients for their industrial products.”