Method for maintaining normal production after the burning-out of a small bushing of a blast furnace

Abstract

The application relates to a method for maintaining normal production after a blast furnace tuyere small sleeve burns out, and relates to the field of steel smelting production. The method comprises the following specific method steps: the normal water inlet flow of the small sleeve is Q1, the water outlet flow is Q2, the water inlet and outlet flow curves are stable, and the water inlet and outlet flow difference is Delta Q12; after burning out, the water inlet flow increases to Q3, the water outlet flow decreases to Q4, part of the cooling water enters the furnace, and the water inlet and outlet flow difference is Delta Q34; blast furnace organizers immediately control the water, the water control is 20%-25%, the water inlet flow of the small sleeve after water control is Q5, the water outlet flow is Q6, and the water inlet and outlet flow difference is Delta Q56; the water inlet temperature of the small sleeve after water control is T1, the water outlet temperature is T2, and the water inlet and outlet temperature difference T2-T1 after burning out is Delta T. The application has the beneficial effects that: the method can effectively reduce the unplanned downtime rate of the blast furnace, improve the operation rate of the blast furnace, provide an effective method for stable production and high yield of the blast furnace, and has practical significance for cost reduction and benefit increase of the steel enterprise, especially the blast furnace iron smelting.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of steel smelting production, in particular to a method for maintaining normal production after a blast furnace tuyere small sleeve burns out. BACKGROUND

[0002] The blast furnace tuyere is an important component for blast and coal injection in blast furnace iron smelting, and is usually composed of a tuyere large sleeve, a tuyere middle sleeve and a tuyere small sleeve. The tuyere small sleeve is installed in the furnace wall between the bosh and the hearth, and is the most inside and the most severe environment among the tuyere large, middle and small sleeves. The tuyere small sleeve not only has to withstand high wind temperature, but also has to withstand the erosion of coke, coal powder and molten slag iron in the high-speed rotation of the tuyere rotation zone. Especially when the blast furnace collapses, suspends, the slag skin falls off, and the hearth is not alive, the tuyere small sleeve burns out more frequently.

[0003] The current traditional operation mode is to replace the tuyere small sleeve after the blast furnace is shut down for slag iron after the small sleeve is found to be leaking. The replacement of the tuyere small sleeve requires the blast furnace to be shut down for 30-120 minutes, and the slow wind process in the process of shutdown operation and restart operation causes great loss to the blast furnace output and economy. SUMMARY

[0004] The present application aims at the deficiencies and shortcomings in the prior art, and provides a method for maintaining normal production after the blast furnace tuyere small sleeve burns out. The method can effectively reduce the unplanned shutdown rate of the blast furnace and improve the operation rate of the blast furnace, thereby providing an effective method for stable and high production of the blast furnace and having practical significance for cost reduction and benefit increase of steel enterprises, especially blast furnace iron smelting.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solution: a method for maintaining normal production after the blast furnace tuyere small sleeve burns out, which comprises the following specific method steps: the normal small sleeve water inlet flow is Q1, the water outlet flow is Q2, the inlet and outlet water flow curves are smooth, and the difference between the inlet and outlet water flow is △Q12; after burning out, the water inlet flow increases to Q3, the water outlet flow decreases to Q4, part of the cooling water enters the furnace, and the difference between the inlet and outlet water flow is △Q34; the blast furnace organizes the operators to immediately control the water, the water control is 20%-25%, the small sleeve water inlet flow after water control is Q5, the water outlet flow is Q6, and the difference between the inlet and outlet water flow is △Q56; the small sleeve water inlet temperature after water control is T1, the water outlet temperature is T2, and the difference between the inlet and outlet water temperature after burning out is T2-T1=△T.

[0006] Further, the following conditions are met after water control in S3: |△Q56-△Q12|≤0.3t / h; the inlet and outlet water flow curves are smooth without fluctuation; no water flows out of the tuyere and the adjacent tuyere; and the tuyere remains bright without dark red or blackening;

[0007] The temperature difference of the water entering and exiting the tuyere small sleeve is not greater than 10 DEG C, and the temperature difference of the tuyere small sleeve after burning out is ΔT≤10 DEG C.

[0008] Further, if the small sleeve burns out again and cannot simultaneously satisfy the above conditions, the water control step of 10%-15% is performed to make the tuyere small sleeve working state simultaneously satisfy the above conditions; if the burning out phenomenon does not occur, the step does not need to be operated.

[0009] Further, the alarm parameters are set according to the difference between the water entering and exiting flow values and the difference between the water entering and exiting temperature values to facilitate real-time and strict monitoring of the running state of the small sleeve after water control.

[0010] Further, the difference between the water entering and exiting flow values after water control and before water control is not greater than 0.3 t / h, that is, |△Q56-△Q12|≤0.3 t / h.

[0011] Further, the temperature difference of the water entering and exiting the tuyere small sleeve after water control is not greater than 10 DEG C, and the temperature difference of the tuyere small sleeve after burning out is ΔT≤10 DEG C.

[0012] After the above technical scheme is adopted, the present application has the beneficial effects that: by adopting the method, the unplanned blast furnace shutdown rate can be effectively reduced, the operation rate of the blast furnace is improved, an effective method for stable and high production of the blast furnace is provided, and the method has practical significance for cost reduction and benefit increase of the steel enterprise, especially the blast furnace ironmaking. DETAILED DESCRIPTION

[0013] The technical scheme adopted in the present embodiment is as follows: it comprises the following specific method steps: S1, the normal small sleeve water entering flow value is Q1, the water exiting flow value is Q2, the entering and exiting flow value curve is smooth, and the difference between the entering and exiting flow values is △Q12; S2, after burning out, the water entering flow value increases to Q3, the water exiting flow value decreases to Q4, part of the cooling water enters the furnace, and the difference between the entering and exiting flow values is △Q34; S3, the blast furnace organizes the operators to immediately control water, the water control is 20%-25%, the small sleeve water entering flow value after water control is Q5, the water exiting flow value is Q6, and the difference between the entering and exiting flow values after water control is △Q56; S4, the small sleeve water entering temperature after water control is T1, the water exiting temperature is T2, and the temperature difference between the entering and exiting water after burning out is T2-T1=△T.

[0014] More specifically, the small sleeve after water control in S3 needs to simultaneously satisfy the following conditions:

[0015] |△Q56-△Q12|≤0.3 t / h;

[0016] The entering and exiting flow value curve is smooth without fluctuation;

[0017] No water flows out of the tuyere and the adjacent tuyere;

[0018] The tuyere remains bright without dark red or blackening;

[0019] The temperature difference of the water in and out of the tuyere small sleeve is not greater than 10 DEG C, and the temperature difference of the tuyere small sleeve after burning leakage is ΔT≤10 DEG C.

[0020] More specifically, if the small sleeve is burned again and cannot meet the above conditions, the water control step of 10%-15% is performed to make the tuyere small sleeve meet the above conditions, and if the burning leakage phenomenon does not occur, the step is not needed.

[0021] More specifically, the alarm parameters are set according to the water flow difference of the small sleeve and the temperature difference of the water in and out to facilitate real-time and strict monitoring of the operation state of the small sleeve after water control.

[0022] More specifically, the water flow difference of the water in and out before and after water control is not greater than 0.3 t / h, that is, |ΔQ56-ΔQ12|≤0.3 t / h.

[0023] More specifically, the temperature difference of the water in and out of the tuyere small sleeve after water control is not greater than 10 DEG C, and the temperature difference of the tuyere small sleeve after burning leakage is ΔT≤10 DEG C.

[0024] The following are specific data of the application:

[0025] Data I

[0026] The water in-flow of the tuyere small sleeve is 40 t / h, the water out-flow is 39.7 t / h, the water in-flow of the tuyere small sleeve after leakage is 40.5 t / h, the water out-flow is 39.4 t / h, the operator controls the water immediately, the water control is 20%-25% to the in-flow of 32 t / h, the out-flow is 31.7 t / h, the curve is smooth without fluctuation, the tuyere is patrolled, no water flows out of the tuyere and the adjacent tuyere, the tuyere camera is strictly monitored, the tuyere is kept bright without dark red or black, the water temperature difference of the small sleeve is strictly monitored, the water temperature difference is 8 DEG C, the cooling water of the small sleeve does not enter the furnace or the water amount entering the furnace is very small, which does not affect the blast furnace production or has a small impact which can be ignored. The small sleeve is replaced after the blast furnace is planed to be shut down for seasonal maintenance under the strict monitoring of the operator.

[0027] Data II

[0028] The water inflow of the small jacket of the blast furnace is 39.5 t / h, the water outflow is 39.2 t / h, the blast furnace condition fluctuates, and after the material collapse, the water inflow and outflow difference alarm of the small jacket of the blast furnace is reported. After checking, the water inflow is 40.0 t / h, the water outflow is 39.0 t / h, the blast furnace organizes the operating personnel to confirm and immediately controls the water, controls the water by 20%-25% to the water inflow of 31.6 t / h, the water outflow of 31.3 t / h, the curve is stable and has no fluctuation, the blast furnace tuyere is strengthened to be patrolled, no water flows out of the tuyere and the adjacent tuyere, the tuyere camera is strictly monitored, the tuyere is kept bright and not dark red or black, the water inflow and outflow temperature difference of the small jacket is strictly monitored, the water temperature difference is stable at about 7.8 ℃, the small jacket cooling water does not enter the furnace or the water amount entering the furnace is very small, which does not affect the blast furnace production or has small influence, and can be ignored.

[0029] After one month of production, the small jacket leaks again, the water is further controlled by 10%-15%, the water inflow is 26.5 t / h after water control, the water outflow is 26.2 t / h, the curve is stable, the water inflow and outflow temperature difference of the small jacket is strictly monitored, and the water temperature difference is stable at about 8.9 ℃. The water inflow and outflow difference of the blast furnace tuyere small jacket, the water inflow and outflow curve, the tuyere brightness, and the water inflow and outflow temperature difference of the tuyere small jacket are within a reasonable range as the standard, so that the blast furnace condition, yield and fuel consumption are not affected, and the water leakage small jacket is replaced when the blast furnace is planned to be blown down.

[0030] The above description is only used to illustrate the technical solutions of the present application but not limit the present application, and other modifications or equivalent replacements to the technical solutions of the present application made by those skilled in the art should be covered in the scope of claims of the present application.

Claims

1. A method for maintaining normal production after a blast furnace tuyere small bush burns out, characterized in that: It includes the following specific method steps: ​ S1, normal small sleeve water inflow is Q1, water outflow is Q2, the inflow and outflow curve is smooth, and the difference between the inflow and outflow is △Q12; S2, after burning leakage, the water inflow increases, the inflow is Q3, the water outflow decreases, the outflow is Q4, part of the cooling water enters the furnace, and the difference between the inflow and outflow is △Q34; S3, the blast furnace organizes the operator to immediately control water, controls water by 20%-25%, after controlling water, the small sleeve water inflow is Q5, the water outflow is Q6, and the difference between the inflow and outflow is △Q56; S4, the water inflow temperature of the small sleeve after controlling water is T1, the water outflow temperature is T2, and the difference between the inflow and outflow temperatures after burning leakage is T2-T1=△T; The following conditions are simultaneously met after controlling water: 1) |△Q56-△Q12|≤0.3t / h; 2) the inflow and outflow curve is smooth without fluctuation; 3) no water flows out of the tuyere and the adjacent tuyere; 4) the tuyere is bright without dark red or black; 5) the difference between the water inflow and outflow of the tuyere is not greater than 10℃, and the tuyere small sleeve △T≤10℃ after burning leakage; if the small sleeve burns leakage again and the above conditions cannot be met simultaneously, the step of controlling water by 10%-15% is performed, so that the working state of the tuyere small sleeve meets the above conditions simultaneously; if there is no burning leakage again, the step does not need to be operated.

2. The method for maintaining normal production after the burning-out of the small bushing of the blast furnace according to claim 1, characterized in that: The alarm parameters are set according to the difference between the small sleeve inflow and outflow, and the alarm parameters are set according to the difference between the inflow and outflow temperatures, so as to facilitate real-time and strict monitoring of the running state of the small sleeve after controlling water.