Foerfarande foer aoteranvaendning av med kvicksilver foercrenade fasta aemnen, pulver och slam

摘要

When a mixture of spent electric batteries is treated by pyrolysis, a pyrolysis slag is obtained having at least a residual mercury content between 50 and 1500 ppm, according to the battery type. It does not seem possible to eliminate this residual content by simply modifying the parameters of this pyrolysis process. The residual content may however be lowered below 10 ppm by a second thermal treatment between 500 DEG c and 700 DEG C. Preferably the material to be treated is crusched between the first pyrolysis and the second thermal treatment, and the second thermal treatment is carried out while air or nitrogen is blown through the material.