Operating Principle

Soil Washing is a flexible and proven process technology, recognized for years as the Best Available Technique (BAT) for various contaminants, including heavy metals and hydrocarbons.

The Soil Washing process is primarily a volumetric waste reduction/minimization technique that achieves the following results:

• Separation of fine soil particles that “host” contamination from the coarser soil fraction.
• Dispersion or solubilization of contaminants in the liquid phase and removal of contaminants from the liquid, enabling the liquid to be reused in the process.

The distribution of contaminants within the matrix depends on several factors, mainly the type of matrix, particle size, as well as the type and concentration of contaminants.

Contaminated soils are classified and washed according to their particle size distribution. Fine particles are separated from gravel, sand, and coarse solid materials using various dry and wet processes.

Contaminants tend to concentrate on fine particles such as silt and clay due to their high adsorptive properties. During the pretreatment and screening phase, gravel, sand, and coarse solids are cleaned and can be reused or redeployed onsite, while contaminants remain in the water and fine particles. These are then subjected to further processing steps, water treatment systems, and sludge dewatering.

Soil Washing and Sediment Washing installations are designed and constructed as either stationary or mobile configurations, depending on the operational needs of each specific remediation project. The facilities are equipped with closed-loop water purification systems and mechanical dewatering lines.

The product range is further complemented by stabilization/solidification and inertization systems, as well as road sweeping treatment and cleanup sand systems.