In July 2018, the two new digesters of Wastewater Treatment Plant Würzburg were inaugurated. They are considered an art installation when illuminated. The concrete buildings with the façade insulation have already been implemented since spring-time and now also the membrane shells are on the digesters. Dr.-Ing. Anke Durth is the responsible project manager for the construction of the two new digesters. "They replace the 40-year-old digesters of the wastewater treatment plant, the capacity of which is no longer sufficient to treat the entire amount of sewage sludge. With the new digesters, the amount of sludge to be disposed of is reduced by one-third and power production is tripled", explains Anke Durth, who has been working for 15 years in the expert committee KEK-1 of the DWA-Board Committee for Recycling/Energy/ Sewage Sludge. The water and sewerage company of the city of Würzburg commissioned DAHLEM with the planning for the new construction of the digesters and several operations buildings, in which the facilities for gas treatment, gas utilization, co-substrate acceptance, etc. are housed.The façade design of the digesters and the operations buildings is the result of an architectural competition. The towers are covered with membrane layers of different shapes, so that two similar but not identical sculptures have been created.
After 26 years of operation, one of the two parallel-fed disc dryers of the sludge drying plant was replaced by a new one at Waste Water Treatment Plant Düsseldorf-Süd. In order to ensure a constant operation of the facilities, the exchange of the other rotor took place already in 2005. Before the replacement of the second rotor, a study showed that the drying of sludge by means of a new disc dryer represented the most favorable solution in terms of operating costs. With a pipe length of 8.6 metres and a heating surface of 400 m², the new disc dryer 2, partly made of stainless steel, provides a throughput of 5.2 tonnes per hour. As the previous plant part was no longer economically viable, the rotor replacement took place in March 2019. For the replacement of the disc dryer, DAHLEM provides the technical equipment planning, from establishing the basis of the project to the award, including construction supervision.