Even though dfferent mining companies handle the steps in a slightly different way but still the basic order of sand mining or…
extracting Sand Blocks in West Bengal, remains the same.
Cut off the vegetation: – Prior to beginning with the sand mining process, the vegetation of the region is completely removed that is cut off.
The removal of the topsoil and the unwanted rock layers: – In order to reach the targeted sandstone, the overlaying soil, as well as the unwanted rock layers are removed. All these materials are stockpiled on the site for later use.
Exposure of the top sandstone and placement of the explosive charges: – Unlike the loose sand on the beach, the sandstone that has to be mined is cemented as a rock. Depending on the hardness of the rock, the explosive charges are placed in the holes that are drilled close to the edge of the wall of the mine, for breaking the sandstone into small pieces.
Excavation of the sandstone: – For excavating the sandstones, equipment like front loaders and backhoes are used. The sandstones are scooped up from the wall of mine pit.
Crushing of the sandstone chunks: – The trucks haul tonnes of sandstones to the crusher that helps in breaking the sandstones chunks into the sand grains. The grains that are a bit larger are separated out for either selling or for manufacturing some other industrial products. Water is then mixed to the remaining fine sand grains, which is finally piped to the washer.
Washing of sand: – The sand grains are then washed in order to remove the unwanted slits and the clay particles if any. Water is then pumped to the nearest settling tank in which the flocculants are added to the water for removing the suspended particles. The finest sand grains that come out finally are supplied for the industrial purposes.
Stockpiling of sand for sorting and then shipping: – The clean sand grains are then stockpiled, sorted, and then loaded into the trucks for shipping.
The rejected materials are allowed to settle out of the water: – The slit and the clay left behind are now moved to the holding ponds to settle out of water. This water is reused for washing and transporting the sand.
Drying of the rejected materials: – Sludges from the settling ponds are allowed to dry before finally adding these to the reclamation stock.
Backfilling the unwanted materials and rocks: – During the reclamation process, backfilling of the mined pit is done with the mixture of the unwanted rocks and the rejected materials. As the wall of the mine is excavated, the space left behind it is filled in constantly. Eventually, the new surface will be graded, then covered with the stockpiled soil, and then will get replanted as per the reclamation plan.
So, these were the basic steps for sand mining. It takes a lot of time in sand mining. Equipment with the best features is now used by the reputed mining industries to carry out the entire process. Quality sand is always in demand and the best equipment along with the right technique of mining can bring out the finest sandblocks.