For industrial sludge, disposal via private disposal companies, via municipal wastewater treatment plants (e.g. also co-digestion of energy-rich flotate sludge) or in approved biogas plants is common. After maximum mechanical dewatering, the sludge is often further treated thermally in drying plants and then thermally utilised or incinerated by these facilities. In the case of production sludge, reuse may also be possible.
Reducing Disposal Costs for Waste and Sludge
Reduce Volume of Industrial Sludge Through Thickening, Dewatering or Drying
In the wastewater treatment process, substances are removed from the wastewater and accumulate as screenings or sludge. In addition, biological processes, but also physical and chemical treatment processes such as the flotation process that is frequently used in industrial wastewater treatment, lead to the formation of sludge.
Residues can also arise directly from industrial production in very liquid form.
Thickening with the HUBER Disc Thickener S-DISC reduces the water content to 90 - 95%.
Sludge dewatering reduces volume and weight and significantly reduces sludge disposal costs.
After dewatering with the HUBER Screw Press Q-PRESS® the sludge is stab resistant.
The HUBER Screw Press Q-PRESS® is available in four different sizes.
Solar sludge drying produces dry granules with the help of solar energy.
The HUBER Belt Dryer BT uses waste heat for thermal drying of sludge.
Process Technology
HUBER solutions for reduction of disposal costs
Depending on the upstream process step, the sludge has a water content of 95 to over 99%, that means it consists mainly of water. Since the disposal of such aqueous sludges is difficult and costly, and transport costs are high, these sludges have to be treated further.
The following process steps are common:
- Sludge thickening: water content is reduced to 90 - 95%, the sludge still behaves as a liquid
- Sludge dewatering: water content is reduced to 60 - 80 %, the sludge is stab resistant
- Sludge drying: water content is reduced to less than 10%, the sludge is a dry material
At least the thickening and dewatering of sludge is common practice directly at the point of origin, i.e. at the industrial plant, whereas sludge drying is only economical for very large quantities of sludge and therefore tends to be carried out in external facilities.
Due to the high compaction of sewage sludge and process sludge, the dry residue (DR) is increased, transport quantities and thus transport costs are reduced to a minimum, and the sludge is optimally prepared for subsequent treatment steps.
HUBER has decades of experience in dimensioning and selecting the optimum machine technology for each sludge treatment application. The HUBER Disc Thickener S-DISC, HUBER Screw Press Q-PRESS® and HUBER Screw Press S-PRESS are mainly used for industrial applications. For preliminary assessment, laboratory tests can be carried out and container-based pilot plants can be provided.
