| 摘要 |
<p>PROBLEM TO BE SOLVED: To recover chlorine contained in combustion gas in the form of a refined calcium chloride which can be used as a regenerated resource and also is safe in handling, when incinerating shredder dust to recover a useful metal or the like as the resources. SOLUTION: When incinerating shredder dust, a generated exhaust gas is made to burn in a combustion furnace in succession to obtain a high temperature combustion exhaust gas, and this combustion gas is brought into contact with an absorbing solution consisting of a calcium carbonate emulsion circulating through a neutralization tank in a concentration column through using the thermal energy of the combustion exhaust gas, and further, a hydrogen chloride-state chlorine contained in the combustion exhaust gas is concentrated as a calcium chloride. In addition, a byproduct gypsum is separated from the obtained highly concentrated calcium chloride, utilizing the solubility difference and a contained heavy metal is removed as a sulfide by adding a sulfiding agent. Next, an obtained highly concentrated calcium chloride solution is electrically heated to make a calcium chloride deposition with the help of a deposition condenser, and thus the calcium chloride is recovered by separation. This method and device for recovering the chlorine from shredder dust are characteristic of the described recovery process.</p> |
