Heating furnace waste heat recovery generating device

Abstract

The invention belongs to the field of heating furnace waste heat utilization, particularly a rolling heating furnace waste heat recovery generating device of the steel plant. The system is mainly composed of a heating furnace waste heat boiler, a heating furnace air preheater, a heating furnace coal gas heat pipe preheater, a heating furnace tail suction fan, a steam overheating boiler, a steam-filling type steam turbine generator unit and a chemical water system and the like. The generating device provided by the invention is characterized by adopting an all-closed system which recovers the waste heat in the heating furnace; and meanwhile, the system is not influenced by the heating furnace production rhythm and the generating steam system and can not affect the original operation condition of the heating furnace, thus the energy conversion efficiency of waste heat recovery can be maximally improved. Compared with the existing heating furnace waste heat recovery device, the device provided by the invention can maximally recover the flue gas waste heat of the heating furnace, increase the temperature of the stream for power generation without affecting the original working condition of the heating furnace, increase the waste heat generated energy, well ensure the operating parameters of the unit and realize the flexible operation mode of a low-pressure steam system of the whole plant. Therefore, the device has good economic benefit.

Description

1. Technical field [0001] The invention belongs to the field of waste heat utilization of heating furnaces, in particular to equipment for recovering and generating electricity from waste heat of rolling heating furnaces in iron and steel plants. 2. Background technology [0002] Generally, steel rolling heating furnaces in iron and steel enterprises, as a major energy consumer of enterprises, directly affect the production costs of enterprises. As a kind of heating equipment, the thermal efficiency of the heating furnace is generally about 30%, which causes a lot of energy waste. Therefore, recovering the waste heat of the heating furnace has both good economic benefits and certain environmental benefits. [0003] At present, most iron and steel enterprises use vaporization cooling walking beam heating furnaces, and the smoke exhaust method is natural smoke exhaust, and the exhaust gas temperature is above 400°C. Adopt waste heat recovery method for air preheating, gas pr...

AI Technical Summary

Problems solved by technology

These methods have some problems in the actual operation process: (1) In order to ensure that the air preheater will not be burned out, the cost of the material used is relatively high, and most of them use a mixed cooling fan to control the exhaust gas temperature of the heating furnace

(2) There are certain potential safety hazards and leakage and waste of using ordinary shell and tube preheaters for gas preheating

This not only failed to achieve the purpose of waste heat recovery, but caused a new increase in production costs

(4) The low-parameter steam generated by the heating furnace using the waste heat boiler and the vaporized cooling walking beam makes the steam use scheduling of the whole plant more complicated and the adjustment more inflexible

[0004] The above situation has led to the following defects in the current heating waste heat recovery system: (1) The waste heat recovery is not complete and the operation mode is not flexible

(2) The low-pressure saturated steam generated by the low-parameter waste heat boiler cannot be completely consumed, resulting in a large amount of emission and increasing the production cost

(3) There are certain potential safety hazards in preheating gas directly with ordinary shell-and-tube heat exchangers

(4) The operation of mixed cooling fans reduces the quality of waste heat and increases production costs

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