The Dutch WWTP Leidsche Rijn, will be significantly expanded to treat also the sewage delivered  from the surrounding villages Maarssen and Maarssenbroek. To avoid construction of additional new treatment reactors and next to the construction of a new clarifier the plant will be equipped with an innovative sieving technology to remove non-dissolved solid materials from the incoming sewage. As a result, the capacity of the existing plant will be finally increased and able to treat sewage from 165.000 citizens in the near future.

By closing the two surrounding WWTP’s  Maarssen and Maarssenbroek, more sewage will be pumped to the nearby Leidsche Rijn WWTP. The capacity of this plant should therefore be increased from 90.000 PE (people equivalent units) to 165.000 PE. This expansion will be, amongst others,  mainly achieved by applying a dedicated sieving technology, which reduces the biological load prior to the current treatment reactors. By sieving the incoming sewage and removing solids from it, there is no need to build additional new biological treatment reactors or a voluminous pre-sedimentation stage to cope with the future loads. The solids, which are sieved out from the incoming sewage, will be dewatered and discharged via existing disposal routes. In future the sieving’s could also be considered for the production of celluloses.

ELIQUO will apply the HUBER Drum Screen LIQUID technology. The sewage will flow by gravity through two new sieving stations. The sieves will be pre-fabricated as package unit plants and will be installed in a new building. Inlet and outlet connections for the new sieves will be made to the existing structures, which includes the screening - and sand removal station as well the distribution  to the two existing biological reactors. Sieving’s that are collected in the Drum Screens are flushed out by an internal removal system. Collected sieving’s will then pass a two-stage dewatering system, in order to be dry stored in containers, ready for dispatch via regular disposal routes.

Furthermore the Drum Screens are equipped with an innovative high pressure cleaning system to clean the screen intensively during regular operation. This dedicated cleaning system avoids comprehensive hot water rinsing systems and use of detergents for cleaning the sieving equipment during operation, which is required by other technologies using filter cloth sieving principles. Our solution reduces the costs for operation of this type of treatment stage significantly, which was confirmed by presenting the lowest total cost of ownership during the tender stage of this project.

ELIQUO will realize this innovative solution together with his partners Dutch Spiral  BV and Van Hattum en Blankevoort BV. The project will be commenced by a design phase after which construction will start during summer 2019. The new Drum Screens will be put in operation during the first half of 2020, after which the WWTP Leidsche Rijn is ready to treat the entire future loads of sewage.

To get an impression, watch our animation of IVOS Leidsche Rijn: start annimation