The new washing plant from CDE is proving valuable for wash water recycling and fine sands recovery
A new washing system being used in a South African quarrying operation has brought major productivity and efficiency improvements.
1288 Natal Portland Cement (NPC) says these have been achieved at its Sterkspuit quarry, near Durban in KwaZulu-Natal on South Africa's east coast, following the introduction of a new washing plant from CDE Global. The loss of quality fines has been eliminated during sand processing due to the use of the CDE Evowash plant, which replaced a bucket wheel de-waterer at the site.
NPC is also innovating with the use of an Aquacycle high rate thickener, which allows 90% of the water used to wash crushed material to be recycled. It is thought to be the first of its kind in a crushed rock or sand and gravel application in South Africa.
NPC operates 11 facilities in South Africa with total production of 1.7million tonnes/year and the sites include seven ready mix concrete plants, three aggregate production plants of which Sterkspuit is one, two grinding plants and one cement plant.
The CDE washing plant is processing Tillite from existing blasting and crushing operations and the washed material is sold for use in various asphalt mixes and as a replacement for river sand in the firm's own concrete plants.
From the crushing plant the minus 9.5mm material is sent to a CDE Prograde P2-75 double-deck rinsing screen fitted with modular Isenmann polyurethane panels on both decks. The Prograde produces a 6.7-9.5mm and a 5-6.7mm aggregate with the minus 5mm material being delivered to the sand washing phase. The Prograde is specifically designed for washing, which is a major advantage when compared to many other screens on offer according to CDE. The design and construction of the spray bar assembly as a fully independent structure is one of the key features of the ProGrade range.
According to CDE, the spray bar assembly is not rigidly connected to the screen box, which cuts vibration and reduces machine downtime. The new plant also cuts losses of both material and water during screening through the use of splash prevention over decks and specialist spray bar seals.
The new CDE washing plant features a proven Evowash 71 system and this unit has helped increase the efficiency of the Sterkspuit operation.
NPC is also innovating with the use of an Aquacycle high rate thickener, which allows 90% of the water used to wash crushed material to be recycled. It is thought to be the first of its kind in a crushed rock or sand and gravel application in South Africa.
NPC operates 11 facilities in South Africa with total production of 1.7million tonnes/year and the sites include seven ready mix concrete plants, three aggregate production plants of which Sterkspuit is one, two grinding plants and one cement plant.
The CDE washing plant is processing Tillite from existing blasting and crushing operations and the washed material is sold for use in various asphalt mixes and as a replacement for river sand in the firm's own concrete plants.
From the crushing plant the minus 9.5mm material is sent to a CDE Prograde P2-75 double-deck rinsing screen fitted with modular Isenmann polyurethane panels on both decks. The Prograde produces a 6.7-9.5mm and a 5-6.7mm aggregate with the minus 5mm material being delivered to the sand washing phase. The Prograde is specifically designed for washing, which is a major advantage when compared to many other screens on offer according to CDE. The design and construction of the spray bar assembly as a fully independent structure is one of the key features of the ProGrade range.
According to CDE, the spray bar assembly is not rigidly connected to the screen box, which cuts vibration and reduces machine downtime. The new plant also cuts losses of both material and water during screening through the use of splash prevention over decks and specialist spray bar seals.
The new CDE washing plant features a proven Evowash 71 system and this unit has helped increase the efficiency of the Sterkspuit operation.
