In January 2008 Dar Al Manajim obtained a licence for the extraction of hard rock from within the north east Briman area of Jeddah province. In March 2008 an order was placed for a state of the art 500 tph Metso Crushing Plant and work began on the initial quarry development to provide the necessary infrastructure and facilities to support such a plant.
In June 2009 a complete Sandvik Mobile Crushing Plant was purchased and delivered to site in order to quickly complete the required quarry floor area and quarry face development work prior to the large Metso Plant being built on the new site. The purchase of this smaller mobile crushing plant operation also assisted in providing saleable products and establishing a customer base prior to the large Metso Plant coming on stream.
The 500 tph Metso Crushing Plant commenced full production in July 2010 working in conjunction with the smaller mobile plant with the following being a description of the crushing processes undertaken at Briman Quarry.
Drilling & Blasting
Drilling and blasting operations are currently carried out by a qualified and experienced sub contractor who provide the necessary drilling equipment and liaise directly with the Police re the deliveries of explosives and the charging process at the blast area. Vertical holes are drilled to a pre-determined depth and pattern set out and agreed with Darmco management. Each blast is carefully engineered to reduce vibration and noise and is fired in a safe and controlled manner.
Primary Crushing
Blasted rock is then loaded by excavator onto dump trucks which haul the rock to the primary dump hopper where the material passes through the large primary jaw crusher. The finer dirty material is then screened off leaving the clean crushed material for processing through the next stage of crushing.
Secondary & Tertiary Crushing & Screening
Primary crushed rock is then crushed through a series of secondary and tertiary crushers and associated screens where the final product size of 0-25mm is achieved.
Quartenary Crushing & Screening
Here the 0-5mm crushed rock fines portion is removed through screening leaving a clean aggregate portion of 5-25mm. This aggregate is then fed into a vertical shaft impactor which shapes the product prior to it being screened into its final single sizes as 25mm, 20mm, 14mm & 10mm. As a result of this VSI quartenary crushing operation Darmco aggregate is of an extremely high quality with regards to aggregate strength with very low flake and elongation content.
Final Products
Large stockpile conveyors then convey each single size aggregate product onto a stockpile where it can then be loaded by a loading shovel directly onto trucks. These loaded trucks are then weighed over our weighbridge located at the quarry offices and then despatched onto our customers throughout KSA where it will be used in the manufacture of concrete, concrete blocks, slabs, asphalt, pipe bedding, drainage materials and other building products.
Environmental / Technological Performance
Our combined crushing plants are fitted with 15 dust filter units which extract and store dust prior to re-discharging into the production process in a safe, clean and controlled manner. All relevant conveyors are also covered to contain dust and a foam/water suppression system is also used to minimise dust emissions. The new Metso Plant is fully automated and is controlled by one man overseeing the whole crushing operation via a computer screen and keyboard from the plant control room.