New Glass Sand Processing Plant

Float glass and container glass are high demand products, and this growing trend is ongoing! To generate these consumables, high quality silica sand must be produced, for which a customer from central Asia contacted AKW Equipment + Process Design to investigate their raw material in our technical center and confirm its potential for use in glass production. Following the positive test protocol and results, the needed plant concept was elaborated and then dimensioned on the basis of the customer‘s wishes (capacity and footprint). The aim of the plant is to significantly improve the chemical composition of the sand and to produce it according to a tight size specification, without compromising on the yield.

A special request was also placed for a thickener AKA-SET in order to minimize the water consumption and allow the plant to run during the harsh winter local conditions.

The overall space available for the plant installation being limited, AKW Equipment + Process Design engineers had to implement a highly customized plant concept.

Project Information

Technical Data

Capacity per Hour	50 t/h
Capacity per Year	> 250.000 t/a
Fresh Water	< 13 m³/h
Process Water	170 m³/h
Compressed Air	5 bar
Installed Power	310 kW

Products

Oversize Material	> 4 mm
Coarse Sand	0.63 – 4 mm
Glass Sand	0.1 – 0.63 mm

Process Flow

By the mean of a wheel loader, the raw material is fed in the box feeder where it is transported to the coarse grain control screen (cut at 4 mm). The particles > 4 mm are diverted and stockpiled.
Through a wear resistant slurry pump, the < 4 mm material is fed to a hydrocylcone AKA-VORTEX for desliming at 100 µm, and the underflow goes to a dewatering screen that will further up concentrate the solid content of the slurry.
This fraction is then directed into the high performance attrition cells AKA-TRIT, where it undergoes a mechanical surface cleaning treatment before it is fed on a multi-deck screening machine AKA-SCREEN for classification at 630 µm (0.63 mm). The oversize particles are stockpiled in a concrete box.
The undersize (0.1 – 0.63 mm fraction) goes to another hydrocyclone AKA-VORTEX which further deslimes the product and adjust the solid concentration before it feeds the spirals  AKA-SPIN. The spirals, typical density separation equipment, ensures that most of heavy minerals are removed from the sandy fraction (so-called lights and middlings fractions). This clean sand, sized at 0.1 – 0.63 mm, is then further deslimed and dewatered before stockpiling, in order to reach the specific customer requirements both in terms of quality and rest moisture content.
Additionally, a water and sludge processing system is integrated to the treatment unit. A high performance thickener AKA-SET ensures a compact sedimentation of the fines present in the process water, to form a so-called sludge. This is performed through to addition of selected flocculants in the process water, while a proprietary rake system that covers the complete thickener tank diameter accelerates the fines sedimentation process and ensures an optimum compacting and dewatering of the sludge. This sludge is then directed with a sludge pump to the sludge pond.

In February 2020 the erection phase started. Due to the pandemic spread, further action had to be put on hold for a period, and the commissioning and training of the customer team was then successfully completed in April 2021.

Impressions

Overall Plant View: customized design to fit into a given tight volume area

AKA-TRIT High Performance Attrition Cells

AKA-VORTEX Flat-bottom Hydrocyclone

AKA-SET High Performance Thickener