| 摘要 |
<p>PURPOSE:To reactivate deactivated lime particles, in a method for purifying exhaust gas by a dry lime process, by hydrating lime particles deactivated by the shells formed to the surfaces thereof by the chemical reaction with SOX, HCl or HF. CONSTITUTION:In a method for purifying exhaust gas by recovering and removing acidic harmful substances from exhaust gas by spraying fine lime particles in said exhaust gas, the particle group recovered by a dust collector 2 is guided to a classifier 4 to be classified into a coarse powder group with a large particle size containing fly ash and a fine powder group with a small particle size containing lime particles having shells comprising the compound with the aforementioned acidic org. harmful substances formed to the surfaces thereof and the lime particles of said fine powder group are hydrated in a hydration reactor 5 by steam and the shells of the lime particles are destructed and removed by volumetric expansion at the time of hydration reaction to prepare recycle lime particles wherein hydration reaction lime exposed to the surfaces thereof and said recycle particles are again supplied to exhaust gas.</p> |
