Water Board Limburg (WBL) is responsible for the transport and treatment of municipal and industrial wastewater and the treatment of sludge in Limburg province (The Netherlands). In 2011, WBL tendered for a new sludge hydrolysis plant at their waste water treatment plant (WWTP) in Venlo. The goals of the plant included increasing biogas production, reducing sludge generation and speeding up the process – resulting in both energy savings and cost reductions.
The board published a tender for the design, construction, operation and maintenance of a new sludge hydrolysis plant. Following a pre-qualification, a competitive dialogue was used to improve the tender specifications and provide space for innovative proposals to be developed. The use of functional specifications also gave bidders more freedom to design novel solutions.
The winning bidder developed a technology to significantly improve the efficiency of sludge treatment. Not only does the new plant match all the goals WBL set out, it also reduces the anaerobic digestion time. Through the procurement process, an affordable thermal hydrolysis sludge treatment technology that lowers the costs and the CO2 emissions of sludge treatment was achieved. The new technology is cheap enough to be used in smaller waste treatment plants. This process saw WBL nominated for the Procurement of Innovation Award 2014.
For more information, visit the European Commission case study.