Stages in Aggregates Processing:
- Primary Crushing
Raw material is transported from the quarry using off road dump trucks and unloaded into the feeder hopper of the primary crushing plants. Typically, the crushing operation is adjacent to the quarry.
From the hopper, the material is brought to the primary jaw crushers via the apron feeder.
The boulders with a maximum size of 0.80 meter are initially crushed in the primary crushers to reduce the size down to 0.25 meter maximum and is conveyed to the surge pile by the jaw conveyor.
Directly underneath the surge pile is an underground vibrating feeder which feeds the surge pile materials through a conveyor up to the initial screening stage known as the scalping screen.
Materials larger than the maximum scalping screen opening of 1 '!h" to 2" are conveyed to the secondary crushing stage while materials that passed through the screen go to the base course or the sub base course product stockpile.
- Secondary Crushing
The secondary crushing is done using a gyratory crusher and after this stage, the materials are conveyed via the main conveyor going to the vibrating screens.
The process involves separation of materials that were crushed into smaller particles and these reduced particles passed through the multi layered vibrating screens. From the screens, the materials are conveyed directly to the different finished product stockpiles..
- Tertiary Crushing
Oversized materials from the first screen deck and the second screen deck go to another crushing stage, the tertiary crushing for further size reduction.
- Stockpiling of Finished Product
From the tertiary crushers, materials are conveyed back to the vibrating
screens by the return conveyor and from the screens then to the individual
finished product stockpiles via the stacker conveyor. The finished products
namely, G-1, 3/4", 3/8" and S-1 are held in stockpiles ready for distribution.