Heating furnace flue gas waste heat recovery system and combustion system

Abstract

The invention relates to the field of recovery and treatment of flue gas from heating furnaces, in particular to a waste heat recovery system and combustion system of flue gas from heating furnaces. It includes a spray cooling tower and an air humidification tower. The spray cooling tower includes a cooling tower body and a first spray device for spraying cooling liquid. The side of the cooling tower body relatively close to the bottom of the tower is provided with a flue gas inlet. The shower device is set in the cooling tower body and is relatively close to the top of the tower, so that the flue gas and the cooling liquid form convection; the air humidification tower includes the air humidifier body and the second spray device for spraying liquid, and the air humidifier body is relatively close to the tower There is an air inlet on one side of the bottom, and the second spraying device is arranged in the air humidifier body and is relatively close to the top of the tower. The liquid outlet of the cooling tower body is connected to the second spraying device, so that the air and the liquid form convection, The air is heated and humidified. It can effectively recover and utilize the waste heat of the flue gas of the heating furnace while reducing the content of NOx in the flue gas.

Description

technical field [0001] The invention relates to the field of recovery and treatment of flue gas from heating furnaces, in particular to a waste heat recovery system and combustion system of flue gas from heating furnaces. Background technique [0002] The heating furnace is a large energy consumer and the main discharge outlet of refining and chemical enterprises. For refining and chemical enterprises, it is of great significance to improve the thermal efficiency of heating furnaces, reduce pollutant emissions, and save energy and reduce emissions. [0003] The existing technology generally adopts air preheating method to recover waste heat of flue gas, and improves energy utilization efficiency by reducing exhaust loss, but the current exhaust gas temperature of heating furnace is generally higher than 100°C. This is because if the flue gas temperature of the heating furnace is lower than 100°C, the conventional air preheater will suffer from low-temperature dew point corro...

AI Technical Summary

Problems solved by technology

Due to the huge heat and low temperature, the conventional air heat exchange cannot recover the latent heat of condensation of this part of the flue gas

Therefore, the existing air heat exchange method is difficult to recover the low-temperature sensible heat and latent heat of condensation of the flue gas, which restricts the further improvement of the thermal efficiency of the heating furnace

[0004] At the same time, with the stringent national environmental protection regulations, the national standard stipulates the emission of heating furnaces, requiring that the NOx content in the flue gas of the process heating furnace should not exceed 100mg / m 3 , refining and chemical enterprises have successively carried out the transformation of low-nitrogen combustion technology, and the current emission has basically reached the national standard, but there are still certain technical difficulties in further reducing the NOx emission in the flue gas of the heating furnace

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