| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the sticking and depositing of melted fly ash in a smaller space near an exhaust gas outlet by avoiding the increase in length of an exhaust gas duct by spraying cooling gas to the exhaust gas of a melting furnace outlet before the fly ash contained in the exhaust gas starts liquefying. SOLUTION: The exhaust gas mixed with melted fly ash is exhausted together with melted slag from the slag hole 2 of a plasma melting furnace 1. Since the gas temperature in the furnace 1 is a high temperature of 1200 deg.C or higher, the slag is completely liquid state, but the structure that can supply city gas E toward the hole 2 is formed to prevent the stopping due to the solidification of the melted slag so that the temperature in the duct near the outlet of the hole 2 can be held at 1000 to 1200 deg.C. In this case, cooling gas is sprayed to the exhaust gas of the outlet of the furnace 1 before the melted fly ash contained in the exhaust gas starts liquefying. That is, the high temperature gas is quickly cooled at once by spraying the cooling gas A supplied by cooling gas supply means 9 via a spray nozzle 7.</p> |
