| 摘要 |
<p>The urban refuse (waste) (21) is dried and combusted in a furnace (2) with mechanical grill (22) in reducing regime, in order to reduce the formation of NOx. The dross is eliminated by being consumed in a well (32), at the base of which a means, such as a plasma torch (35), is arranged for vitrifying the dross. The combustion gases are burnt in the presence of secondary air in a circulating fluidised-bed furnace (5). Most of the flying ash is removed from the fumes in a filter (61), before the fumes are passed through a boiler (7) where they are cooled. Further on, the fumes pass through a purifying region (8) which is per se conventional, before being removed via a flue (chimney) (10). This produces very little toxic waste, either in the fumes or in the dross. The flying ash which is collected downstream of the fluidised bed (5) is recycled with the dross to be vitrified. The heavy metals volatilised in the furnaces are recovered via the purge (83). <IMAGE></p> |
