| 摘要 |
PURPOSE:For harmless, elution-free heavy metal treatment, heavy metal-containing waste liquid is absorbed by silicic inorganic adsorbent and made in sludge which is then fired for treatment. CONSTITUTION:Waste liquid containing Cr, Cd, etc discharged from metal surface treatment or inorganic chemical insustry is treated by adjusting its pH to 5 to 9 to precipitate a substantial part of heavy metals as hydroxides. This is then added with silisic inorganic adsorbent such as zeolite particulates below 100 mesh to adsorb the remaining heavy metals. The so formed sludge contains adsorbent and heavy metals which is separated, dried and heated to be sintered for treatment. The heavy metals are thus trapped in the sintered products and free from elution, thus rendering them harmless. |
