Flame length controllable high-efficient burner

Abstract

A length-controllable high-efficiency burner comprises a mixed precombustion chamber, a throat section, a middle switch-in port, a middle circuit and a middle nozzle. On the refractory annular block or the pouring body on top of the mixed precombustion chamber is disposed a top circuit with at least one top nozzle. One end of the top nozzle is in communication with the mixed precombustion chamber, and the other end of the top nozzle is in communication with the top circuit connected with a medium branch pipeline.

Description

technical field [0001] The invention relates to the fields of metallurgy, gas-fired power generation, cement production, glass production, etc., and specifically relates to a burner, which is especially suitable for but not limited to top-combustion, external-combustion and internal-combustion hot blast stoves for blast furnace (and non-blast furnace) ironmaking. Background technique [0002] The ironmaking process accounts for more than 65% of the total energy consumption of iron and steel production. Every technological advancement to reduce energy consumption in the ironmaking process can generate huge benefits for enterprises and contribute energy saving benefits to the society. The use of hot air smelting in blast furnace (and non-blast furnace) ironmaking is the main and key technical measure to greatly reduce the energy consumption of the process. The higher the temperature of the hot air, the greater the benefit of energy saving and consumption reduction. The functio...

AI Technical Summary

Problems solved by technology

At present, the burners used in internal combustion hot blast stoves are backward sleeve type and relatively advanced rectangular type, and the burners used in external combustion hot blast stoves are circular sleeve type and porous type, all of which have the following defects: 1) service life Short, generally 5 to 8 years, the highest is 15 years; 2) The fine streams are cross-cutting and mixed with each other, and the mixing intensity is weak, which is a long-flame burner; in order to achieve the desired combustion efficiency, sufficient time and space for mixed combustion are required , the height of the fire well on the upper part of the combustion chamber is very high; the higher the fire well height, the greater the project investment and the worse the stability of the partition wall

3) The required excess air coefficient is high

Production practice shows that there are serious defects: the service life of the burner and the vault is generally only 1 to 3 years; the flame burning in the checker bricks leads to a rapid decrease in the overall performance of the hot blast stove

Compared with the first generation, the second-generation technology has made significant progress in terms of structural stability and service life. The layout still has the following defects and deficiencies: 1) All the rings and nozzles are arranged in the middle of the burner, and are set according to the ideal conditions of curing, without any flame length adjustment means, and the specific operating conditions such as medium pressure, temperature, flow rate, etc. It is constantly changing, and any parameter change will cause the mixing and combustion conditions to deviate from the ideal state, and cause the flame length to be too long or too short; 2) The medium air flow in the middle of the mixing pre-combustion chamber is a swirling flow, resulting in medium air flow density segregation (center Low density and less quantity at the part, high density and more quantity around the wall), low utilization rate of co-combustion space and affect co-combustion effect; 3) The longitudinal area of ​​each medium is too thick, the initial mixing conditions of the two media are poor, and the rotary cutting mixed The power and strength are not enough, and a higher co-combustion space is still required; 4) The swirl-mixing combustion is incomplete along the upper pre-combustion chamber and the middle main combustion space, and the burnout point (ie, the highest point of flue gas temperature) extends into the checker brick, Therefore, in actual production, the temperature of the vault at the end of combustion is lower than the temperature of the vault at the early stage of air supply, and the combustion in the checker bricks will seriously affect the life of the checker bricks in this area and the overall thermal performance of the hot blast stove; The use of silicon checker bricks is more harmful (the flame is in direct contact with the silica bricks); 5) The temperature difference between the burner's mixed combustion chamber during the combustion period and the air supply period is as high as 300°C, and the long-term, periodic, and frequent fluctuations reduce the temperature of the burner. Service life; 6) The combustion efficiency is not high and insufficient, and the excess air coefficient required is still high

Images