Novel testing and adjusting method for coke oven side combustion chamber

Abstract

The invention discloses a novel method for testing and adjusting a side combustion chamber of a coke oven, which belongs to the technical field of thermal regulation of coke ovens and mainly comprises the following steps of: opening a small turning plate of a coal gas air door of a side waste gas shutter into two grids and fixing the two grids; an air damper small turning plate of the side waste gas shutter is opened into five grids and is fixed; the opening degree of an air door at the upper parts of the two inserting parts is reduced to 60mm; and a side adding and reducing cock of the side combustion chamber is driven to a fully-open position. By means of the method, the horizontal curve of the side combustion chamber can be optimized from a steamed bun shape to an oblique line shape, and the lower fire of the heat storage chamber can be eliminated.

Description

Technical Field

[0001] The invention relates to the field of coke oven thermal technology, and in particular to a new method for measuring and adjusting a coke oven side combustion chamber. Background Art

[0002] The "steamed bun-shaped" horizontal curve appears more frequently when the amount of gas, air and exhaust gas does not match the suction force, that is, the actual suction force that drives the gas movement is greater than the suction force required for normal gas movement, causing most of the gas and air to be sucked into the middle of the coke oven.

[0003] However, the gas and air of the side combustion chamber come from two exhaust plates and small flues, one is the exhaust plate and small flue connected to the resistance wall, and the other is the normal exhaust plate and small flue. The exhaust plate and small flue connected to the resistance wall only provide gas and air to the side combustion chamber, so the suction force required by this exhaust plate and small flue is less than that of other exhaust plates and small flues. Since blast furnace gas is used for heating, if the suction force of the downdraft of the second-to-last small flue is reduced, the combustion of the second-to-last combustion chamber will be affected.

[0004] The traditional approach is to expand the air door, increase the cross-sectional area of ​​the air flow, consume more suction, and thus increase the temperature of the burner head, so that the horizontal curve changes from "steamed bun type" to "sawtooth type" to "oblique line type". However, since the heat stored in the heat storage chamber of the side combustion chamber is less, when the heat in the heat storage chamber is sufficient in the early stage, the horizontal temperature curve can meet the requirements, but after running for a period of time, the accumulated heat is not enough to meet the preheating requirements, and the horizontal curve returns to the original "steamed bun type".

[0005] From the industry's perspective, for coke ovens heated by blast furnace gas, fire under the small flue is a common problem. The normal treatment method is to use hot repair methods, remove the sealing wall of the burning regenerator, take out the checkered bricks inside the regenerator, and if it is the main wall, replace the coke oven gas pipe bricks for repair. If it is a single wall, use spraying or smearing to repair it. However, the repair requires the furnace to be cooled down. The coke oven masonry has a poor ability to withstand rapid cooling and heating, and it is easy to cause damage to other parts of the coke oven. The current coke oven adopts a regenerator compartment design. When removing the wall, the original compartment of the regenerator needs to be broken, which is difficult to restore.

[0006] After each temperature measurement, since the temperature regularity of the side combustion chamber is poor, in order to ensure that the temperature can be stabilized within a reasonable range, it is necessary to frequently adjust the adding and subtracting valves. However, the single adjustment range of the adding and subtracting valves is too large, and the temperature changes are also large.

[0007] As the valve is turned down, the gas volume decreases. Under the condition that the suction force of the smoke duct remains unchanged, the remaining gas and air are sucked to the middle of the coke oven. The gas and air allocated to the side fire ducts are insufficient, and the horizontal curve tends to be more like a steamed bun. The temperature of the fire duct in the furnace head fluctuates frequently and greatly, and thermal stress cracks appear in the coke oven masonry.

[0008] The fundamental reason for the fire in the small flue is the leakage between the gas and air single walls of the side heat storage chamber. The air entering the air heat storage chamber of the rising airflow leaks into the gas heat storage chamber through the cracks in the wall, and combustion occurs inside the heat storage chamber. Therefore, just to eliminate the fire in the small flue, we need to prevent the air from leaking to the gas.

[0009] There are two adjustment ideas for the steamed bun-shaped horizontal curve. One is to lower the high temperature point in the middle, and the other is to raise the low temperature point of the furnace head fire channel. Moreover, since blast furnace gas is used for heating, the vertical fire channel in the middle cannot reduce the temperature by reducing the nozzle diameter like coke oven gas heating, so we need to control the pressure to change the steamed bun-shaped curve. Summary of the invention

[0010] The purpose of the present invention is to solve the problem that the temperature change regularity of the coke oven side combustion chamber in the thermal adjustment work currently using blast furnace gas for heating is poor and does not conform to normal temperature fluctuations. The traditional method adjusts the gas volume through a valve, and the horizontal temperature curve easily presents a "steamed bun shape", the temperature of the furnace head changes greatly, cracks appear in the masonry of the partition wall of the coke oven heat storage chamber, and the heat storage chamber often has fire problems. A new method for measuring and adjusting the coke oven side combustion chamber is proposed.

[0011] To achieve the above object, the present invention provides the following technical solution: a new method for measuring and adjusting the combustion chamber beside a coke oven, which is applied to a regenerative coke oven using blast furnace gas heating, double fire channels, exhaust gas circulation, blast furnace gas and air side entry, and regenerative chamber compartmentation, and the method comprises the following steps in sequence:

[0012] S1. By measuring the horizontal curve of the side combustion chamber, confirm that the horizontal curve of the side combustion chamber is a "steamed bun shape";

[0013] S2. When the exhaust gas shutter is in the process of rising airflow, open the observation hole of the exhaust gas shutter and confirm through the observation hole that there is a phenomenon of fire from the heat storage chamber to the small flue inside the small flue;

[0014] S3, the gas and air damper small flaps at the bottom of the movable exhaust gas switch enable the small flaps to be flexibly adjusted;

[0015] S4. Open the small flap of the gas damper of the exhaust gas switch to 2 spaces and fix it;

[0016] S5. Open the small flap of the air damper of the side exhaust switch to 5 grids and fix it;

[0017] S6. Reduce the air door opening on the machine side to 60mm;

[0018] S7. Turn the addition and subtraction cock of the combustion chamber to the fully open position;

[0019] S8. Use the waste gas analyzer to sample the waste gas from the ascending airflow of the adjacent fire channel generated by the blast furnace gas fed into the side blast furnace gas branch pipe in the side combustion chamber to determine the excess air coefficient. If the excess air coefficient is within the range of 1.05-1.15, it means it is qualified;

[0020] S9. If the excess air coefficient is less than 1.05, expand the air door by 1mm, adjust the air door, and re-measure the excess air coefficient until the excess air coefficient is qualified;

[0021] S10. If the excess air coefficient is greater than 1.15, reduce the air valve by 10 mm, adjust the air valve, and re-measure the excess air coefficient until the excess air coefficient is qualified.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The changing pattern of the horizontal curve is: steamed bun type → sawtooth type → oblique line type, which shows that the method is feasible in terms of temperature regulation; through the method of the present invention, the problem of fire under the small flue is solved, and the red-burned small flue furnace wall returns to its original color; in the case of excess air, the flue gas analyzer is used to measure the oxygen content of the rising and falling airflows provided by the exhaust gas disk of the side heat storage chamber in the vertical fire channel, which is ≥3%, fully meeting the combustion requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the operation structure of the present invention;

[0025] Figure 2 It is a "steamed bun-shaped" horizontal curve diagram of the present invention;

[0026] Figure 3 It is a "slash type" horizontal curve graph of the present invention;

[0027] Figure 4 It is a schematic diagram of the phenomenon of underfire existing inside the small flue of the present invention;

[0028] Figure 5 It is a "diagonal line type" horizontal curve graph of the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Example

[0031] The present embodiment provides a new method for measuring and adjusting the combustion chamber beside a coke oven. A group of coke ovens in the present embodiment are numbered 1# and 2#, which are 2×65-hole JNX3-70-1 type 7m coke ovens. Blast furnace gas is used for heating, with a turnover time of 22.5 hours and a standard temperature of 1285 / 1335°C. The blast furnace gas cyclone on the coke side of the 1# regenerator is closed by 1 / 3, the machine side damper opening is 120mm, the air and gas small flap openings are 3 grids, the coke side damper opening is 130mm, and the air and gas small flap openings are 3 grids; the blast furnace gas cyclone on the coke side of the 2# regenerator is fully opened, the machine side damper opening is 150mm, and the coke side damper opening is 160mm; the furnace head on the coke side of the 1# carbonization chamber is black coke, and smoke is emitted when pushing the coke; during the rising airflow, the sampling port of the exhaust gas switch on the coke side of the gas regenerator 1 is opened, and it is observed that there is a fire phenomenon inside the small flue, such as Figure 4 ; The horizontal curve of the No. 1 combustion chamber is a "steamed bun" shape. Figure 2 .

[0032] The method of this embodiment is used to further measure and adjust. In this embodiment, the 1# regenerator of the 1# coke oven is selected for measurement and adjustment, which includes the following steps in sequence:

[0033] S1. By measuring the horizontal curve of the side combustion chamber, confirm that the horizontal curve of the side combustion chamber is a "steamed bun shape";

[0034] S2, when the exhaust gas shutter is in the process of rising airflow, open the observation hole 7 of the exhaust gas shutter, and confirm through the observation hole that there is a phenomenon of fire from the heat storage chamber to the small flue inside the small flue;

[0035] S3, the gas small flap 4 of the movable exhaust gas switch and the air damper small flap 3, so that the small flap can be flexibly adjusted;

[0036] S4, open the gas damper small flap 2 of the side exhaust gas switch to 2 grids and fix it with bolts;

[0037] S5. Open the air damper flap 1 of the side exhaust gas switch to 5 grids and fix it with bolts;

[0038] S6. Reduce the opening of the machine side air door 8 to 60mm;

[0039] S7, turn the side increase and decrease cock 5 of the combustion chamber to the fully open position;

[0040] S8. Use the waste gas analyzer to sample the waste gas from the ascending airflow of the adjacent fire channel generated by the blast furnace gas fed into the side blast furnace gas branch pipe in the side combustion chamber to determine the excess air coefficient. If the excess air coefficient is within the range of 1.05-1.15, it means it is qualified;

[0041] S9. If the excess air coefficient is less than 1.05, expand the machine-side damper 8 by 1 mm, adjust the damper, and re-measure the excess air coefficient until the excess air coefficient is qualified;

[0042] S10. If the excess air coefficient is greater than 1.15, reduce the machine-side damper 8 by 10 mm. After adjusting the damper, re-measure the excess air coefficient until the excess air coefficient is qualified.

[0043] After the above work is completed, when the side exhaust gas shutter is in the process of rising airflow, open the observation hole of the exhaust gas shutter and check the fire situation inside the small flue through the observation hole. Check that there is no flame coming down from the heat storage chamber in the small flue, and close the observation hole of the exhaust gas shutter. Measure the horizontal temperature of the side combustion chamber. The horizontal curve has changed from "steamed bun type" to "slash type". Figure 5 Observe the maturity of the coke at the furnace head before pushing the coke to confirm whether the coke at the furnace head is evenly mature.

[0044] The method utilizes a pressure measuring device, and connects both ends of the pressure measuring device to the observation holes of the side gas and air exhaust switch.

[0045] The fundamental reason for the fire in the small flue is the leakage between the gas and air walls of the side heat storage chamber. The air enters the gas heat storage chamber through the cracks in the wall, and combustion occurs inside the heat storage chamber. Therefore, in order to eliminate the fire in the small flue, we need to prevent the air from leaking into the gas. By measuring the suction at the exhaust gas plate of the rising airflow, we found that the suction on the air side is greater than that on the gas side. This is the fundamental reason for the large suction difference on both sides and the leakage. Therefore, we need to increase the pressure on the gas side and reduce the pressure on the air side.

[0046] There are two points in the adjustment of the steamed bun-shaped horizontal curve. One is to lower the high temperature point in the middle, and the other is to raise the low temperature point of the furnace head fire channel. In addition, because it is heated by blast furnace gas, the middle vertical fire channel cannot reduce the temperature by reducing the nozzle diameter like coke oven gas heating. So we need to change the steamed bun-shaped idea by controlling the pressure.

[0047] According to the traditional method, we can increase the temperature of the burner by expanding the air door, so we can use this idea in reverse and use more gas and less air.

[0048] The purpose of fully opening the small gas flap is to allow relatively more exhaust gas to pass through the gas heat storage chamber, fully preheat the gas before combustion, and ensure that the gas can be fully burned.

[0049] As the air valve is reduced in size, the amount of air entering the combustion system is also reduced. In order to reduce the suction force, the small flap on the air side is closed to one level.

[0050] Although the temperature of the side combustion chamber does not conform to the law of temperature change, we can only control the maximum temperature to ensure that high temperature signals do not appear.

[0051] If the fire is still going out, it means that the air pressure is still greater than the gas pressure, so we can continue to reduce the damper.

[0052] If the furnace temperature rises sharply due to delays in furnace discharge, our temporary treatment measure is no longer to turn down the valve but to close the valve completely. The purpose is to ensure that each partitioned heat storage chamber can pass through the appropriate gas flow.

[0053] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new method for measuring and adjusting the combustion chamber at the side of a coke oven, characterized in that: The steps are as follows: S1. By measuring the horizontal curve of the side combustion chamber, confirm that the horizontal curve of the side combustion chamber is a "steamed bun shape"; S2. When the exhaust gas shutter is in the process of rising airflow, open the observation hole of the exhaust gas shutter and confirm through the observation hole that there is a phenomenon of fire from the heat storage chamber to the small flue inside the small flue; S3, small flaps of gas and air dampers of movable exhaust gas switch, so that the small flaps can be flexibly adjusted; S4. Open the small flap of the gas damper of the exhaust gas switch to 2 spaces and fix it; S5. Open the small flap of the air damper of the side exhaust switch to 5 grids and fix it; S6. Reduce the air door opening on the machine side to 60mm; S7. Turn the addition and subtraction cock of the combustion chamber to the fully open position; S8. Use the waste gas analyzer to sample the waste gas from the ascending airflow of the adjacent fire channel generated by the blast furnace gas fed into the side blast furnace gas branch pipe in the side combustion chamber to determine the excess air coefficient. If the excess air coefficient is within the range of 1.05-1.15, it means it is qualified; S9. If the excess air coefficient is less than 1.05, expand the air door on the machine side by 1mm, adjust the air door, and re-measure the excess air coefficient until the excess air coefficient is qualified; S10. If the excess air coefficient is greater than 1.15, reduce the air door on the machine side by 10 mm. After adjusting the air door, re-measure the excess air coefficient until the excess air coefficient is qualified.

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