Reducing the fresh water consumption

Several modern technologies have been employed by sand and gravel companies to ensure that gravel could be quarried in an environmental-friendly way. The mechanical separation technology using centrifuges has been employed in quarries where a large quantity of gravel water with a high content of fine particles is generated. The wash water is fed through a stationary pipe into the feed zone located in the center of the scroll for solid-liquid separation. The scroll rotates at a slightly different speed than the bowl and deposited solids are transported toward the conical end of the bowl. Wolkersdorf, a sand and gravel sales company, has been operating a process water treatment plant using a Flottweg Decanter for dewatering the separated sludge that significantly reduce the fresh and ground water consumption. The sludge is separated using different sieving devices and disc clarifiers and then flocculates are introduced that ensure the reduction in operating costs.