摘要 |
<p>After pulverizing to minus 200 mesh, a mixture of coal and pyrite particles is passed through an A.C. silent corona discharge in the presence of a reactant gas. Simultaneously, the particles are de-agglomerated and an electrical or magnetic difference between them is enhanced. Thereafter, the pyrite is separated from the coal. The effectiveness of the pulverizing step in separating pyrite particles from the coal matrix, especially small-size particles approximately 50 micrometers and less, is enhanced by pretreating the coal with a chemical comminutant. One example is a solution of ammonia, used to presoak the coal for a short time, at, for example, atmospheric pressure and ambient temperature.</p> |