HUBER Grit Washer RoSF4 T Treatment of partly dewatered grit from wastewater treatment plants

Q: "What are the characteristics of a good grit washing system?"

"A good grit washing system is characterised by its ability to wash out the organic substances in the grit so that the loss on ignition in the washed grit is < 3%. In addition to the effective separation of organic and mineral components, the retention of fine sands is also decisive in practice, which is taken into account in the design of HUBER Grit Washing Plants."

Q: "What happens to the grit from the grit chambers within a wastewater treatment plant?"

"In order to be landfilled, the grit must be further treated before. Depending on the size of the sewage treatment plant and the amount of grit, grit classifiers or grit washers are used. The state of the art is now the grit washer."

Q: "Why is grit washing needed?"

"In municipal wastewater treatment, grit is separated in a grit trap. This separation takes place by sedimentation, i.e. the grit settles in the grit chamber after sufficient retention time. However, since there are not only mineral substances such as grit in the wastewater, but also many organic solids, these also settle to a greater or lesser extent. As a result, when the grit is discharged from the grit chamber, it sometimes contains a large amount of organic solids. This contamination of the grit with organic matter hinders, among other things, cost-effective landfilling or reuse of the grit.\r\nGrit washing with a HUBER Grit Washer RoSF4 solves this problem and produces clean grit with an organic content of less than 3% loss on ignition, the HUBER Grit Washer RoSF G4E reduces the organic content to \u2264 5%."

Q: "Why should subsequent grit washing be implemented after grit separation?"

"Conventional grit classifiers separate virtually all solids contained in the grit trap effluent. This classified and partly dewatered grit is usually more or less contaminated with organic particles. With further treatment in a subsequent grit washer, the organics are separated from the mineral particles."

The HUBER Grit Washer RoSF4 T provides an efficient and cost-effective solution for washing and dewatering grit, while reducing organic content and minimizing disposal costs.

Reduced disposal costs
Less than 3 % organic content
Very high solids content of > 90 %
Easy retrofitting, seamlessly integrates with existing grit classifiers

Conventional grit separation

Conventional grit classifiers separate virtually all solids contained in the grit trap effluent. This classified and partly dewatered grit is usually more or less contaminated with organic particles.

Subsequent grit washing

The classified grit is therefore further treated in the subsequent grit washer to separate organic material from mineral particles. This ensures a cleaner end product and reduces organic content in the grit.

HUBER Grit Washer RoSF4 T

Classifying screw with subsequent HUBER Coanda Grit Washer RoSF4 T

The HUBER Grit Washer RoSF4 T washes the classified grit from a HUBER Circular Grit Trap HRSF

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Design sketch: Flow diagram

Design and Function

Design sketch: Flow diagram

The combination of conventional grit separation and subsequent washing ensures high performance and cost efficiency, making it an excellent solution for modern wastewater treatment plants.

By introducing upwardly directed service water, the grit in the lower part of the HUBER Grit Washer RoSF4 T is fluidized, creating a grit fluidized bed. In this fluidized bed, lighter organic particles are effectively separated from the denser grit particles, regardless of their size.

The process is further assisted by a central stirrer that keeps the particles in motion. Once the organic material has been removed, the clean grit is conveyed by a classifying screw, statically dewatered, and then discharged into a container.

The removed organics are automatically discharged with the introduced wash water.

The Benefits of the HUBER Grit Washer RoSF4 T

Reduced disposal costs due to lower organic content in the grit
High dewatering efficiency of washed grit up to 90 % dry residue
Organic content reduction to < 3% loss on ignition
Throughput capacity up to 3.0 ton / 3.0 m³ solids per hour
Low investment costs

Easy installation and smooth retrofitting after grit classifiers, in complete plants, or in circular grit traps
Long-lasting design with grit removal screw supported on both ends to minimize wear
Maximum corrosion protection

Downloads

Customer Information and Documents

Brochure: HUBER Grit Washer RoSF4 T

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FAQ

Frequently Asked Questions

A good grit washing system is characterised by its ability to wash out the organic substances in the grit so that the loss on ignition in the washed grit is < 3%. In addition to the effective separation of organic and mineral components, the retention of fine sands is also decisive in practice, which is taken into account in the design of HUBER Grit Washing Plants.

In order to be landfilled, the grit must be further treated before. Depending on the size of the sewage treatment plant and the amount of grit, grit classifiers or grit washers are used. The state of the art is now the grit washer.

In municipal wastewater treatment, grit is separated in a grit trap. This separation takes place by sedimentation, i.e. the grit settles in the grit chamber after sufficient retention time. However, since there are not only mineral substances such as grit in the wastewater, but also many organic solids, these also settle to a greater or lesser extent. As a result, when the grit is discharged from the grit chamber, it sometimes contains a large amount of organic solids. This contamination of the grit with organic matter hinders, among other things, cost-effective landfilling or reuse of the grit.

Grit washing with a HUBER Grit Washer RoSF4 solves this problem and produces clean grit with an organic content of less than 3% loss on ignition, the HUBER Grit Washer RoSF G4E reduces the organic content to ≤ 5%.

Conventional grit classifiers separate virtually all solids contained in the grit trap effluent. This classified and partly dewatered grit is usually more or less contaminated with organic particles. With further treatment in a subsequent grit washer, the organics are separated from the mineral particles.

Case Studies