Sand Washing
Sand washers are selected based on certain factors. These include space availability, water availability, end product requirement, finance and labour.
Professionals in the aggregates industry would agree how important a sand washing machine or a sand washer is in the scheme of things. This device which is used to remove dirt, dust and other impurities from sand and other materials, works on the principles of washing and dewatering to separate the solid particles from the water in the material.
A sand washing machine usually consists of a feed hopper, a washing drum or trommel, a spiral blade or screw and a slurry pump. While the feed hopper introduces the material to be washed into the machine, the washing drum or trommel rotates the material as it is fed through the machine. The spiral blade or screw is used to lift and transport the material through the machine, and the slurry pump is used to remove the excess water from the material.
The movement of the drum helps to remove any dirt or impurities that may be present in the material. The spiral blade separates the dirt and impurities from the sand and the slurry pump removed the excess water from the material. The dewatered sand is collected in a container, finally. A sand drying machine is usually used along with the sand washing machine to dewater the sand after it has been washed. This helps to further remove any moisture from the sand so that it can be used for various applications.
Sand washers are selected based on certain factors. These include space availability, water availability, end product requirement, finance and labour. Washers occupy the last stage in an aggregate processing plant and space constraints must be taken into account, so that there is enough availability for loading by haul trucks. Lean design makes way for above the ground feed points such that existing conveyor setups can be used, taking leverage of the available height.
Conventional washers are high water demanding equipment and so, an additional dewatering screen will prevent additional water from going away through the output. Latest washers have inbuilt valve mechanisms to control the amount of water going into the sedimentation pond, allowing remaining water to be recycled back into the sump.
Conventional washers only produce a single grade of sand while products are sometimes being upgraded to produce dual grades of sand whose quality comes under question. Material mixing mechanisms in the screen gives way to control the gradation of the output product to pass relevant standards.
Conventional washing equipment are cheaper, easy to install and operate but the 30% overflow is a concern. Equipment with poor retention capacity allows for saleable material to be washed. Newer models are actually high initial investment equipment but the break-even is achieved sooner than conventional washers. Latest washers can be operated only be an adequately-skilled workforce, unlike the conventional washers. It is important for the team to understand the operation and maintenance of slurry pump, hydrocyclone and drives.
There are many players manufacturing sand washing plants. Cflo has Combo which is an advanced construction sand production technology. As per details on their website www.cfloworld.com, with a capacity range of 50 to 500 tonnes per hour, the patented Combo mobile sand washing plant takes all the innovation of the ground breaking CFlo technology and gives it the power of mobile.
Our sand washing technology, proven over the last many years with hundreds of installations, is helping our customers maximise the quality and value of their washed sand products for a variety of applications in the construction, mining and industrial sand sectors, reads their website.
The Combo revolution integrates the tried and tested water recycling technology allows customers to use the latest sand washing technology while reducing the water requirement by up to 95%. Sandmaster SP series of Sand wash plant from WEIR are efficient, reliable and rugged single-grade sand wash plants designed for robust performance and low cost of ownership.
As per their website www.global.weir.com, this product has been designed to remove excess fines or coarse material in a simple way, providing exceptional washing results while delivering clean, low moisture product for conveying or stockpiling. The SP series discharges one type of sand. Sandmaster SP sand wash plants allow for simple and easy maintenance with a sump inspection hatch and all discharge and connection points designed to be operated with ease. The product offers rapid assembly, maximum recovery, low energy consumption and low cost of ownership. They can also be used to remove unwanted fines or clay, convert crusher dust to saleable sand, recover saleable sand from effluent stream, recover tailings and grit and wash recycled materials and construction waste. These sand wash plants can be used to wash a range of feed materials such as silica sand and frac sand.
Propel Industries also manufacturers sand washers SW series that adopt advanced technology for high efficiency sand washing. As per details on their website www.propelind.com, the sand washer has cartridge type bucket wheel and spiral arrangement bucket speed controlled by VFD which in turn controls the percentage of fines. It has high-tech planetary gear reducer for better and efficient maintenance.
Propel Dual sand washing machine is a wheel bucket type equipment which is mainly used for washing, classification of end products M-sand and P-sand. It has very low energy consumption and low maintenance costs.
Propel Eco wash provides consistent solutions for all material and mineral washing needs. It offers excellent reliability, ease of transport and fast onsite installation. It facilitates the accurate separation of silt and clay from the washed sand products.
Propel Pro Wash series is designed to ensure maximum efficiency from the washing plant. It facilities the extremely accurate separation of silts and clays from the final washed sand products (M-sand & P-sand). It is employed in the production of specialised sands.
