Sludge Cylinder®

In the summer of 2015, Promeco launched a revolutionary innovation: the Sludge Cylinder®. Purpose: large processing capacity for sludge dewatering on small surface areas as found in urban areas. This innovation has emerged almost twenty years after Promeco pioneered the development of dewatering sludge with the help of geotextiles/dewatering containers.

Advantages of the Sludge Cylinder®:

  • In conventional geotextiles, you cut open the textile so that you can dispose of the sludge; the textile cannot be recycled. If you excavate the sludge from the Sludge Cylinder® from above, you can infinitely recycle the textile. In other words: extremely cost-effective if you are able to deploy it on a regular basis.
  • In addition: with the Sludge Cylinder®, you dewater sludge on small surface areas as found in urban areas, for example in excavation pit. Conventional dewatering techniques require much more space.

The photos below show an example measuring approximately 11 metres in diameter (capacity 250 cubic metres). The size can be easily adapted by omitting circular sections (minimum diameter is 6 metres).

Important: although overlapping applications exist, the Sludge Cylinder® is not a direct competitor for the existing geotextiles: the new application is a supplement to the possibilities. The deployment of well-known dewatering containers (geotextile dewatering tube) is, for example, a more logical option if the dewatering will take a long time.

The process

You can view the process in the diagram; click on the diagram it to zoom in. As an example, the flocculant requirements and the production are stated above the visual fictitious characteristics of the sludge. The calculated quantities in all phases of the process are stated underneath. Promeco prepares these calculations (a so-called mass flow balance) beforehand for each project. This provides us with a good insight of the desired dewatering process. The data is used in the software that calculates the optimal dosing of flocculant during the entire project. In the short term, we provide you with the opportunity to calculate the mass flow balance yourself at this location by inputting the required data.

Our expertise enables us to work efficiently and effectively, allowing you to save on your investment. However, there are even more advantages: read more about these on the Sludge dewatering page.

What can we see on the illustration? The in-situ dredging spoil is pumped up by a dredging pump, a process in which a lot of excess water is included. The dredging spoil is pumped through a dredging pipe to the Sludge Cylinder®. During the pumping, Promeco continuously measures the dry solids content and flow rate of the dredging spoil. In the processing computer, where the data for the mass flow balance has been entered, based on the measurements, it is continuously calculated how much flocculant we need to use for the dosing. This then takes place further along in the pipe, possibly adding a quantity of mixing water. A mixing device in the pipe then mixes the flocculant with the dredging spoil. Ultimately, dredging spoil dosed with flocculant ends up in the Sludge Cylinder®, where the sludge particles will quickly settle. The geotextile acts as a filter for the sludge flocks, so that the released water is completely clear. This clear water is routed back to the original surface water.

Eight photos and two videos

Click below for two video’s: clear water coming from the Sludge Cylinder® of Promeco! These are .mov-files, together 2 mb.

You can find eight photos below the videos: click on them to zoom in. The Sludge Cylinder® can be transported in compact form and can be operational within one working day so that the dewatering of sludge on a small surface area can be commenced. The processing capacity is large, and the water that is produced is extremely pure.


Promeco patented this groundbreaking innovation.