ABSTRACT
The washing (extraction) technologies used for removal of polluting chemicals from soil are based on several mass-transfer stages (Hursthouse, Mohammed et al,). Multistage washing with differential distribution of water/extraction agent during the different stages is an efficient system for cost-saving during the soil cleaning process. A typical example of this process is decanting of discrete materials in the chemical industry. The cascade method developed during research work by Shandyba et al, (1998) utilizes mass balance and kinetic equations with unequal efficiency and mass-transfer parameters at every stage (Figure 1).
