Efficient wash water processing in the sand and gravel industry – Flottweg’s centrifuge technology in focus

The extraction and processing of sand and gravel plays a major role in the construction and raw materials industries. Throughout such processes, a significant amount of wash water that contains fine solids is generated. The efficient cleaning and reuse of this water presents a technical and ecological challenge. With its innovative solution, Flottweg, a leading provider of centrifuge technology, offers a sustainable and economically attractive alternative to conventional settling ponds.

The challenge presented by wash water

When processing sand and gravel, the raw material is washed to remove unwanted elements such as clay, silt, and organic matter. The resulting wash water contains fine solids that do not settle easily, however. Traditionally, these residues were collected in settling ponds – a process that requires a lot of space, is maintenance-intensive, and poses ecological risks.

“In the past, settling ponds were used, but since some of the water contains contaminants, these days it is preferable for 100% of the water to be put into circulation without being temporarily stored in nature,” explains Robert Klug, Flottweg sand and gravel sales engineer.

Flottweg’s solution: inclined clarifier + centrifuge + water tank

Flottweg uses a closed-circulation system consisting of three key components: an inclined clarifier, a high-performance centrifuge and a large water tank. This combination enables almost the complete recovery of the process water.

This is an area in which the centrifuge plays a crucial role: it processes the superfine particles which were previously directed into settling ponds. The centrifugal technology generates up to 1,750 times the force of gravity – a quantum leap in separation performance compared with natural sedimentation at 1 G. The result: a compact solid and a clear, reusable centrate.

Strength through wear protection

A key element of Flottweg centrifuges is their durability – including with abrasive materials. The scroll helixes are armored with silicon carbide, one of the toughest materials on the market. Silicon carbide bushings also ensure minimal wear at critical points on the machine. This enables the centrifuge to process highly contaminated raw materials on a reliable, durable basis.

Economic effectiveness and sustainability

In addition to its technical efficiency, the system also offers impressive economic benefits. According to Flottweg, investing in a centrifuge typically pays for itself within five years. A significant cost factor is eliminated. “Compared with the previous costs of having to dredge the settling ponds once or twice a year, investing in a centrifuge certainly pays off,” explains Robert Klug.

The system also makes an important contribution to sustainability. It reduces space requirements, minimizes environmental risks and allows for a closed water circuit – a crucial advantage in an era of increasing water scarcity and stricter environmental regulations.

Summary

With its centrifuge technology, Flottweg offers a pioneering solution for the processing of wash water in the sand and gravel industry. With its combination of technical efficiency, economic profitability and ecological responsibility, the system is an attractive alternative for companies seeking to modernize their processes while also making them more sustainable.

Find more information about Sand and Gravel and Flottwegs solution for the washing process.