Every year in the Netherlands about 95,000 tons of aquafer is generated (62,000 tons of liquid aquafer and 33,000 tons of dewatered aquafer). Reststoffenunie (now AquaMinerals) disposes of this water company residual and finds outlets for it in a variety of applications, such as in bioenergy plants, WWTPs and as a construction material. The transformation of dewatered aquafer into granular material makes a further expansion of the sales opportunities possible. The pellets can be used as filter medium, for example in gas and air cleaning (H2S binding) or water treatment (removal of phosphorus and heavy metals). The pellets can also be used in the development of nature areas (phosphorus binding in water courses and soil).
It is key that the pellets be of consistent and well-defined quality. Mechanical properties are important to avoid pulverisation. Physical-chemical properties guarantee the proper functioning of the material in gas and water treatment. The challenge is to produce stable pellets with sufficient adsorption capacity.
In the first place it is necessary to produce pellets of a consistent quality. Each specific application requires pellets with specific properties. This demands an optimised production process and well developed logistics, which can deal with quality variations in the available raw material (irons sludges). In addition, the pellets’ properties and the various targeted applications for the granulated aquafer have to be tested in practice. Before the product is finally marketable, it must meet all regulatory requirements and its final destination following its use needs to be established.
Availability of granular aquafer as a commercial product for applications in, for instance, water treatment, nature development and agriculture, and gas cleaning.