摘要 |
<p>57 A method of cleaning contaminated soil which achieves very low levels of residual impurities and does not produce contaminated residues is characterised by the steps of
(a) feeding the contaminated soil to a combustion space (6) of a fluidised bed furnace (4) having, at the underside of said combustion space, a structure (5) for air distribution,(b) forming a fluidized bed of the contaminated soil above said air distribution structure (5) in the combustion space by means of combustion air delivered under elevated pressure via the air distribution structure, and(c) mainly or completely burning the impurities from the soil in the combustion space (6), to provide cleaned soil. Preferably the air distribution structure (5) comprises a generally horizontal grid (7) of pipes having air distribution nozzles with gaps between the pipes, coarse soil particles passing through said gaps into a collection space (13) from the combustion space.</p> |