”Sewage Sludge Day” at HUBER

Scientists, planners and plant operators met to discuss the challenges of sewage sludge disposal on 23 July 2019 at an expert forum organised by HUBER SE. More than 300 guests had come to inform themselves and listen to the excellent presentations of the experts that both provided an overview of the legal framework and showed practical solutions.

The well-attended Europahalle at Berching

CEO Georg Huber welcoming more than 300 guests at the sewage sludge expert forum in Berching

The Bavarian Minister for the Environment and Consumer Affairs Glauber as patron of the event underlined in his video message, among other, the necessity of intercommunal collaboration in order to meet the challenges of future sewage sludge disposal.

CEO Georg Huber opened the event that took place in the Europahalle at Berching, reminding the audience in his welcome speech that the first HUBER Sewage Sludge Day was organised 15 years ago.

The moderator of the event, Professor Norbert Dichtl, director of the Institute for Sanitary Engineering of the Technical University of Braunschweig, explained in his introductory speech the legal regulations setting the framework for sewage sludge disposal. Especially the new German Fertilizer Regulation and Waste Sewage Sludge Ordinance are playing a prominent role in this context. This results in the necessity to provide increased capacity for sewage sludge mono-incineration plants and in an increased demand for economical methods of phosphorus recovery.

Markus Gleis of the German Federal Environmental Agency reported then about the present situation of sewage sludge disposal in Germany. Approximately 1.8 million tons dry mass are generated annually in Germany. In 2016, approximately 65% of it were used for agricultural purposes, 24% for thermal utilisation and 11% went to landscaping projects. He also stated the German Federal Environmental Agency’s position when it comes to the future of sewage sludge: abandon agricultural sewage sludge utilisation and recover phosphorus and energy from sewage sludge.

Professor Mocker of the University of Applied Sciences Amberg-Weiden dealt with the topic of thermal sewage sludge utilisation. He demonstrated the advantages and disadvantages of decentralized and centralized solutions for sewage sludge drying and further thermal sewage sludge utilisation. He explained in detail the different technical solutions available presently but finally concluded that the proven technology of mono-incineration in a fluidised bed furnace is the technology of choice.

Experts spoke about their practical experience and projects they have implemented. Ulrich Jacobs pointed out the importance of intercommunal cooperation and showed with the example of a sewage sludge cooperation in the northeastern German state Mecklenburg-Vorpommern what to consider when uniting 15 wastewater authorities into one cooperation and what are the challenges to overcome in this process. Harald Erber of STW Innsbruck reported about the successful installation of a HUBER Belt Dryer BT on the sewage treatment plant Innsbruck. Mr. Ziegler of STW Bayreuth told about his practical experience with the HUBER solar sewage sludge dryer and provided also interesting insights into the decision process that led to choosing a solar dryer.

Professor Günthert introduced to the audience the Platform for coordination of municipal sewage sludge utilisation in Bavaria (PKB). The task of this organisation, among other, is to support Bavarian municipalities in establishing partnerships (with economy or as intercommunal cooperations) and promote the exchange of expertise with researchers and suppliers of options for sewage sludge utilisation.

Jan Kirchoff of Glatt Ingenieurtechnik GmbH picked up the topic of phosphorus recycling, which is closely connected with the issue of sewage sludge disposal. He presented the PHOS4green method that manages to convert sewage sludge ash to phosphorus fertilizer. A large-scale plant with a processing capacity of 60,000 t sewage sludge ash per year is currently under construction.

Insight into the activities of a sewage sludge disposal company was given by Johann Emter of Emter GmbH. On their thermal sewage sludge utilisation plant, they process 140,000 t sewage sludge per year. The sewage sludge ash generated on site is utilised as fertilizer. Due to the great demand, they are planning to increase the incineration capacity of the plant with the installation of a HUBER Belt Dryer BT 24.

As representative of WTEB, Thomas Roitzsch reported about the project Halle-Lochau, a thermal sewage sludge utilisation plant with slude2energy GmbH as contractor. sludge2energy is a joint enterprise between the companies WTE Essen and HUBER SE. The plant at Halle-Lochau is designed for a capacity of approximately 33,000 t/a dewatered sewage sludge and 2,750 t/a dried sewage sludge. Commissioning of the plant is scheduled to take place in September 2020. WTEB as a subsidiary of WTE Essen will take over the operation of the plant.

The successful event was closed with a summary provided by Professor Dichtl who once again reflected on the many aspects of sewage sludge disposal. Everyone interested was finally invited to join a tour of the HUBER factory to get an impression of the different machines and plants manufactured there for the treatment of wastewater and sludge.