Van Dijk heating is introducing the SOREM sodium remover. This new technology removes sodium very selectively from closed water systems. The nutrients in the treated water are preserved for the crop. The unique procedure stands out because of its purity and high capacity. On average, one unit is enough to maintain a low-sodium, closed water system at a nursery of 10 hectares.
There are many nurseries with closed water systems where gradually increasing sodium concentrations make it necessary to discharge drain water into the surface water with some regularity. Nutrients, including phosphate and the nitrogen components nitrate and urea, are also lost in the process. On 1 January 2027, the so-called zero emissions for nitrogen components will enter into force in the EU. In essence, this means that horticultural companies will then no longer be allowed to discharge drain water, and water systems must remain - virtually - completely closed. To continue to reuse drain water responsibly, horticultural companies need to have technology that removes sodium from water selectively. The SOREM sodium remover does this very effectively.
The removal process is based on ion exchange by means of a resin column and additives. During the process, the additives (nitric acid, caustic potash and CO2) are converted into potassium nitrate, a common fertilizer.
The open structure gives the resin column a large active surface, which binds a lot of sodium. As soon as the saturation point is reached, the resin column is “discharged” in a separate process stage. The concentrated sodium solution drains into the sewer. Most of the additives remain behind in the system, where they make a second contribution as a nutrient component in the form of potassium nitrate. This means that the net use of additives is extremely low.
By using SOREM, growers opt for an advanced, very selective technology with a high efficiency rate. Barely any nutrients are lost, which means sustainable, closed cultivation within the legal limits remains possible. On average, one unit is enough to maintain a permanent low-sodium, closed water system at a nursery of 10 hectares. The capacity may turn out to be higher or lower, depending on the quality (sodium levels) of the irrigation water and the fertilizers used.