Contaminated soil treatment technologies

Synopsis

Contaminated Soils are destinated to become a major problem in densely populated countries. Land disposal prohibitions will require that these soils must be treated using best demonstrated available technology.

Various possibilities exist in soil decontamination, organic contaminants can be incinerated, separated by washing or biologically treated.

Inorganic contaminants can be separated by washing, extracted or leached by acids and can be solidified.

Lurgi has broad experiences in all kind of waste incineration; primarily applied are incineration in the grate incinerator, multiple hearth furnace, fluidized bed incinerator, atmospheric circulating fluidized bed incinerator, special combustion chambers (incineration of TNT contaminated soils) as well as the rotary kiln.

For remediating contaminated soils, Lurgi has developed a wet mechanical separation process using only water for cleaning the soil. Plants are designed as semimobile systems.

Dredging mud, a disposal problem or raw material for the building industry. To solve this problem Lurgi developed a stepwise process, separating the mud into sand and silt, dewatering the silt fraction, producing silt pellets and converting the silt pellets into hard-burnt ceramic products replacing natural gravel for concrete production by thermal treatment. Harbour sediments with high amounts of organic and inorganic contaminants are thus converted to building material, a contribution to save raw materials by recycling.