Four common combustion technologies in industry

　　Warm air combustion technology

　　Also known as regenerative combustion technology, it is an efficient waste heat recovery energy-saving technology. The regenerative combustion technology refers to alternately switching air or gaseous fuel and flue gas to flow through the regenerator, which can recover the sensible heat of the high-temperature flue gas to the greatest extent, and the exhaust gas temperature can be lowered to below 180 ℃， which can be used for combustion. The medium or gaseous fuel is preheated to above 1000 ℃ to form a new flame type different from the conventional flame, and the commutation combustion makes the temperature distribution in the furnace more uniform. At present, China has successfully applied regenerative combustion technology in industrial furnaces such as steel kiln, aluminum melting furnace, forging furnace and ladle roaster.

 

　　Pulse combustion technology

　　It is a method of intermittent combustion, using pulse width modulation technology to achieve temperature control of the furnace by adjusting the on-off ratio of the combustion time. This technology makes it easier to control the furnace temperature of the furnace, so the temperature field in the furnace is uniform and the temperature fluctuation is minimal, and fuel can be saved. In recent years, this technology has been gradually promoted and applied in the control of industrial furnace combustion systems such as metallurgy and ceramics, with good results.

 

　　Oxygen-rich combustion technology

　　It is an efficient intensive combustion technology with oxygen content in the combustion air exceeding the conventional value. Oxygen-enriched combustion technology can reduce the burning point of fuel, accelerate the combustion reaction speed, promote complete combustion, reduce the excess air coefficient, reduce the amount of flue gas after combustion, and thus improve the efficiency of heat utilization. Oxygen-enriched combustion technology is more suitable for high-temperature industrial furnaces, such as metal heating furnaces and glass melting furnaces. There are data showing that forging furnaces can save 1/4 of fuel if they use 23%~25% oxygen-enriched air to support combustion.

 

　　Staged combustion technology

　　It means that the insufficient amount of air is sent to the main combustion zone by changing the air supply mode to form excess combustion of the oxygen-deficient fuel, and then the remaining air is added in the second-stage combustion zone to form a lean combustion zone of the fuel to complete the entire combustion process. Staged combustion can reduce the emission of nitrogen oxides. According to the results of the project operation, the nitrogen oxide emissions in the exhaust gas are reduced by about 35% after using the graded air combustion technology.