A JIG washer, a well known and widely used installation in gravel washing, is mostly used to clean poluted soil. This innovative technique within the field of the soil purification, is used to clean the debris fraction from organic impurities. Where a washing sieve is only capable of sieving and washing items of a predetermined size, a JIG washer can make a densimetric separation. Heavier parts are separated from lighter, floating material.
A mixture of debris and organic fractions are introduced into a water bath. Pulsating movements create upward and downward flows. This causes the heavier fractions to separate from the lighter floating parts. The heavy parts at the bottom of the machine are discharged onto a de-watering sieve. The floating fraction are brought onto another de-watering sieve.