Furnace Fires and Explosions

The Institution of Chemical Engineers markets Ha/ards Workshop 005, which is entitled Furnace Fires and Explosions. [1] One of the advertising leaflets for this workshop makes the following generalization Furnaces are comparatively simple items for a plant, and because they are unsophisticated they tend to be imperfecdy understood by operators and plant managers alike. Their tolerance to abuse is limited, and once abused their useful life can be drastically shortened. Worse still they may fail suddenly, since furnace tubes distort easily and then fracture. Such failure is often severe, with a consequential fire and/or explosion. ... 

Institution of Chemical Engineers, Furnace Fires and Explosions, Hazard Workshop Module 005, Rugby, U.K. (available as a training kit with 23 35mm slides, booklets, teaching guides, and related materials). 

The Institution of Chemical Engineers markets "Hazards Workshop 005, which is entitled Furnace Fires and Explosions. [1] One of the advertising leaflets for this workshop makes the following generalization ... 

The flammability and explosivity of high-sulfur petroleum coke dust (particle size <75 pm) were examined. Air-dried powder was non-explosive but fire-prone above 400°C. A 5 mm layer became incandescent at 420-470° and a dust cloud ignited at 520-660°C [1]. The fire and explosion hazards of petroleum coke or anthracite, when used in the manufacture of furnace electrodes, may be reduced by heat treatment [2],... 

Therefore, there is a tendency for a large plant to be situated in an open space. The best arrangement is to put the plant in a separate structure covered only with a light roof. If this is not possible, attention should be given to the situation of collection and storage, units and furnaces. All those units as far as possible should be outside the building or inside a fire-resistant enclosure. Also essential is the position of the central room and electrical switch rooms and how they will be affected by fire and explosion. 

Protection of fired equipment (heaters, furnaces) against accidental explosion and fire. 

Advancement of the munitions in the demil operations by conveyors to the furnaces and explosive agent destruction operations have been reviewed with possible failure modes, fire, toxic release, and deterrent actions. 

The chemistry laboratory has additional hazards. Open flames, ovens and furnaces can cause fires and bums. Cold storage rooms and their contents, notably dry ice and liquid nitrogen, may cause freeze burns. Corrosive acids and other chemicals can cause chemical skin bums and internal damage from inhalation, ingestion and absorption through the skin. Many chemicals are poisonous chemicals should not be tested by taste or smell. Compressed gases constitute inhalation, explosion and fire hazards if handled improperly. 

In the event of a Pb-Bi leak into or out of the furnace, neither fire nor explosion will occur. Pb-Bi has the advantage of being non-flammable and virtually non-chemically reactive in contact with liquid water, unlike sodium or potassium. The environmental implications of a lead leak into a high temperature smelting vessel require evaluation before such a coolant could be applied in the metallurgical industry. 

High/low fiimace pressure Loss of draft control High pressure Loss of containment, fire and gas escapes causing damage to property, seal, and personnel, explosion Low pressure Furnace implosion, damage to seal, excess dtaft, combustion... 

The recovery boiler in question was heavily damaged and all four water walls and most of the fiimace floor had to be replaced. The explosion opened up all four comers of the furnace from the firing gun level (third floor) to the roof ( 30 m), and buck stays were sheared off at the comers. Some openings were as wide as 1.2 m about halfway up the wall. The water walls were displaced over 1 m and left a corrugated pattern in the walls where they were constrained by buck stays. 

The first explosion occurred without warning. One man 14 ft from the furnace was knocked off his feet. No fire or smoke was reported. About 5 sec later a second and more violent explosion occurred. The entire area... 

Although fire damp/ which is mainly methane, and choke damp (carbon dioxide) are frequent causes of mine accidents, Dr. William Brownrigg learned how to make good use of them. In 1741 he communicated to the Royal Society several papers on the gases of coal mines, but preferred to withhold them from publication until he could prepare a comprehensive treatise on the subject. His laboratory at Whitehaven was provided with several gas furnaces of his own design and a constant supply of fire damp from the nearby mines. Because of his skill in foretelling explosions by the rapid fall of the barometer, mine operators often consulted him. 

Startup heaters - electrical or direct-fired types - are used to heat synthesis gas for the converter dining startup. Some of the problems encountered with these heaters are hydrogen-induced tracks, overheating and flame impingement, thinning at bends, and furnace explosions. Normally, SS321 is used for startup heater coils and the downstream pipeline88. 

---