Sand & Gravel, Claybound Aggregates
0-4mm, 5-10mm, 10-20mm & +20 mm sand
In Attichy-Bitry, Oise, Antrope, a subsidiary of Eiffage Travaux Publics, operates an alluvial quarry where it extracts sand for the concrete market. The company turned to CDE to replace an ageing mobile installation which was no longer reaching the required performance level (screen belt conveyor and wheel sand washing machine). Unusable in its original state, the sand extracted in the Antrop quarry has to be washed and screened. For 6 years, the operator had been using a screening belt conveyor but “its production was limited to 50t/h and the sand wasn’t processed well enough or dried sufficiently”, says Samuel Wendel, head of operations at Antrope.
After seeing it in operation in the UK, the operator bought a CDE M2500 mobile washing plant, the first to be installed in France. The M2500 is composed of three distinct and dissociable elements: a 9 m3 hopper, a 14 m feed conveyor (with a 1,000 mm belt) and the washing unit consisting of a 7 m2 two-deck screen, a hydrocyclone and a dewatering screen. A variable speed feeder feeds the sand to the feed conveyor.
At this level, it undergoes a first cut at 25 mm on the upper screen, then at 5.5 mm and finally at 10 mm. These last two cuts are made on the double deck screen. Under the screen, a tarpaulin collects the 0-4mm which is pumped to the hydrocyclone. The 5-10mm is collected in a second tarpaulin and transported by a water flow to the dewatering screen. This fraction is transported by the general supply pump with clear water.
Run by an electric actuator (less than 200kW), the M 2500 washing unit produces four different types of sand: 0-4mm, 5-10mm (which is taken up by the water circuit), 10-20mm and over 20 mm. Thanks to its automatic system, the M2500 can run for a full cycle, all year round, without the need to intervene in the washing unit. It’s only a one man job to start up the washing unit, supply the unit with sand and load the trucks that come to get supplies. Another special feature is that there is no weighbridge, and everything relies on the loader and its on-board weighing system. Afterwards, all the data from the weighing system can be transferred to Antrope's headquarters for integration into a standard weighing software.
For the operator, the objective has been achieved, since he has succeeded in producing 100-120 t/h of sand that can be sold after 24 hours of storage, to the operator’s great satisfaction. This sand is intended for use in concrete applications, especially in batching plants.
Material Claybound Aggregates, Limestone, Quarry Waste, Crushed Rock, Sand & Gravel
Output 0 - 5mm | 5 - 10mm | 10 - 20mm | 20 - 90mm | +90mm
Material Crushed Rock, Quarry Waste, Limestone, Sand & Gravel
Output Concrete sand | 40-50mm, 20-40mm, 14-20mm and 5-14mm aggregates
Material Sand & Gravel, Claybound Aggregates
Output 0 – 2mm building sand | 0-4mm coarse sand | 4 – 10mm gravel | 10 – 20mm gravel | 20 – 40mm gravel | +50mm oversize