FIRING PREVENTER FOR ASH DEPOSITED IN BOILER

• Main Authors: KATSUMURA SHINICHIRO, TOMII TAKASHI
• Format: Patent
• Language: English
• Published: 24.11.2000
• Edition: 7
• Subjects: BLASTING; HEATING; LIGHTING; MECHANICAL ENGINEERING; METHODS OF STEAM GENERATION; STEAM BOILERS; STEAM GENERATION; WEAPONS

PROBLEM TO BE SOLVED: To lower the temperature of a boiler quickly after extinguishment by disposing a temperature detecting means and a nozzle means for ejecting cooling fluid in a layer of ash deposited at a part in a boiler where the ash is deposited easily thereby preventing the ash deposited on the bottom part in the sub-chamber of the boiler from firing. SOLUTION: Ash ascending from the combustion chamber 1 of a boiler flows, by a small quantity at a time, into the sub-chamber 2 of the boiler through a gap 9 at the water-cooled wall penetrating part of the heat transfer tube 4 of a superheater and ash deposits 3 on the bottom. Since boiler water for adjusting temperature does not circulate through the heat transfer tube 4 and the header 5 of a superheater after the boiler is extinguished, temperature in the sub-chamber immediately after extinguishments of the boiler is about 450-550 deg.C which is substantially equal to the steam temperature. Temperature measuring nozzles 12 and cooling spray nozzles 10 are provided side by side in the sub-chamber 2 of the boiler and when the internal temperature of ash deposited 3 on the bottom exceeds 200 deg.C, inactive gas, e.g. nitrogen gas, or extinguishing water is sprayed from the cooling spray nozzles 10.