The advanced treatment of sewage sludge or industrial residual sludge is increasingly gaining in importance also for industrial customers. Whereas, until recently, the common strategy was to pass the sludge on to disposal companies at low costs, this has now become more and more complicated, difficult and especially more expensive due to the modified and now more stringent German Fertilizer Regulation and Waste Sewage Sludge Ordinance and because of the generally increasing costs in the disposal industry.
Therefore, industrial customers increasingly concern themselves with strategies how to additionally treat their sludges on site using the residual heat from the process or wastewater. In addition to the significant sludge volume reduction and the utilisation of exhaust heat energy, the dry sludge, due to its high heat value, often represents also a valuable fuel for use in the own incineration plant on site.
HUBER customers from disposal industries chose the opposite approach. They are service providers for municipalities and industries, establishing centralized sludge treatment centres with utilisation of residual heat from other treatment technology units. On the other hand, customers from the power plant and energy supply sector are interested in refuse derived fuel, not least because coal combustion will be abandoned in the future, secure for themselves sewage sludge contingents and invest into the appropriate drying technology.
HUBER SE provides comprehensive customer advice, depending on the specific requirements up to the thermal utilisation of the sewage sludge. Contact us!
Project: paper industry in Brazil
A paper industry in Brazil generates with its own wastewater treatment plant up to 45 m³/h (1 – 5 % DS) surplus sludge. Up to now, the surplus sludge has been dewatered and transported to a landfill.
For cost reasons, the sludge will in the future be dewatered to > 21% with five HUBER Screw Press Q-PRESS® 800.2 units and then dried to approx. 90% solids content with a HUBER Belt Dryer BT 30. The dryer is designed for a throughput of 45,000 t dewatered sewage sludge.
The dried sludge is fed to the company’s own biomass incineration plant and the energy produced there is used for sewage sludge drying – a cycle with optimal exploitation of otherwise unutilized heat sources.
Delivery and installation of the plant components starts in the middle of 2019, commissioning is planned for the beginning of 2020.
Project: disposal industry in Germany
A disposal company in Southern Germany provides the service of disposing residual materials from municipal sewage treatment plants (grit trap material, screenings, sewage sludge) and diverse types of sludge and residues, mainly form the food industry, industrial kitchens and other industrial companies.
To increase the capacity and economic efficiency of their plant, they have decided to install a HUBER Belt Dryer BT 24 with up to 40,000 t/a throughput capacity. The installation of the dryer is scheduled to take place at the end of 2019, commissioning in spring 2020.
Furthermore, in the medium term, they also want to recover phosphorus from the dried sludge.