The most sensible way to dispose of contaminated waste: We use the structural properties of your waste to protect and stabilise decommissioned areas of the mine.
Typical waste for underground recovery:
- Fly ash from waste incineration plants
- Sinter dust from the metal industry
- Aluminium filter dust
- Contaminated soil and rubble
- Waste containing salt
- Sludges from chemical-physical treatment and galvanic sludge
We deposit your waste in cavities that formerly served as potash and rock salt mines. The law stipulates that mining areas which no longer meet today's safety standards must be backfilled.
Thanks to the location of the cavities between impermeable clay and salt layers, your waste is stored for the long-term. With five underground recovery plants, K+S has the largest capacity in Europe, fit to last for decades to come.
To permanently secure an underground cavity, a filling material with specific physical properties is needed. Some waste provides those required characteristics. When it does not, we achieve this by combining various materials (conditioning). Our engineers have developed numerous special processes for conditioning and processing, and further research on the subject is ongoing.
K+S has been in the underground recovery business for 25 years. Depending on the properties of the waste and the nature of the cavity, we employ a number of different methods.
In stacking, the waste is packed into big bags, stacked in the mining chambers and any gaps are filled in with salt. The aim is to make a flush connection to the surrounding rock mass. To achieve the required stability and compressive strength, some waste must be conditioned. As a result of this process, waste with higher pollution content can also be recovered.
From pneumatically transportable waste, suspensions which cure at their destination are formed using specially designed formulas. That the individual substances are mixed in such a way that they flow through the kilometre-long, intertwining system of pipes, then cure at the right time, and ultimately keep all fluids in, is a science in itself. K+S engineers have specially developed the sludge mixing station using highly sophisticated technology.
In this process your waste is deposited loosely, packed in big bags or sacks as a backfilling material before being compacted.