SU821495A1 - Device for measuring blasting material amount in tuyere apparatus rf blast furnace - Google Patents

Description

one

The invention relates to ferrous metallurgy, in particular to devices for controlling the consumption of blast-furnace

to blow.

The closest to the invention to the technical essence and the achieved result is a device for determining the flow rate to blow by pressure drop at two points of supply lines to blow to the lance, including a common (annular) air line with a positive pressure discharge pipe blowing, fixed knee with a minus pressure pick-up tube, - movable knee with. charm, nozzle and lance IJ

However, negative pressure tapping holes are often clogged, and when the furnace is taken up, the lining softens on the traction line. The magnitudes of the measured pressure drop and its changes in this device are small, which does not allow to ensure the necessary accuracy in determining the flow rate calculated by the formula

Q - KTPG,

where Q is the flow rate to blow, m / min; h - pressure differential blowing

(pressure difference) according to measurements in positive and minus connections, mm of water. st;

K - calibration coefficient. The magnitude of the coefficient K may be changed by the measure of the profile change in the path between the pressure measurement points.

The purpose of the invention is to improve the reliability, accuracy of flow determination by blowing tuyeres and facilitating maintenance. .

The goal is achieved by the fact that each negative pressure tapping nozzle is installed in a moving knee point, while in the electronic system between the measuring units and the number you additionally entered, a unit for determining the flow coefficients blows tuyeres.

Installing the negative nozzle in the movable knee point and using a flexible metal sleeve to connect it to the impulse track greatly simplifies the maintenance of pressure selection devices. In addition, an increase in the distance between the pressure points increases the magnitude of the useful signal, and the measurement accuracy also increases.

FIG. .1 shows the proposed device; in fig. 2 - work diagram.

In FIG. 2 simultaneous recording of the pressure drop of the annular air duct - the fixed wheel curve A) and the annular air duct - the point of the movable knee curve B) the measurement accuracy in the second case is 13.5% higher than in the first one.

The device for determining a hot blow includes an annular air duct 1, a stationary elbow 2, a movable elbow 3, a nozzle 4, and a lance 5 fixed in the wall of the hearth 6. Measurement unit 7, including positive 8 and negative 9 nozzles for pressure extraction, is installed to determine the flow rate block 10 for determining flow rate calibration coefficients to blow; block 11 for calculating flow to blow; and block 12 for correcting flow to blow.

The device works as follows.

The blast from the annular air duct 1 through the stationary elbow 2, the movable knee 3, the nozzle 4 and the lance 5 enters the blast furnace. In this case, using the positive 8 and negative 9 pipes of the block 7 is measured. It does not determine the pressure differential between the annular air duct 1 and the movable elbow 3, the value of which in calculating block 11 using the calibration coefficient K, which is in the memory device of the calibration coefficients determining unit 10, is calculated as the flow through the tuyere compared to the required (specified ) its consumption. and with the help of the actuator of the correction unit 12 for blowing, a corresponding adjustment of the flow is carried out. Continuous pressure drop measurement, flow calculation and correction allow you to continuously maintain the flow rate at a predetermined level.

The value of the calibration coefficient K is usually determined by bench testing of the tuyere devices of the construction used before installing them on the blast furnace. However, during the manufacture of the tuyeres, deviations are possible, and during operation changes in the configuration of the supply path are blowing between the measuring points, pressure 8 and minus 9 branch pipes. At the same time, the value of the calibration coefficient determined during bench tests will not correspond to its actual value, which will introduce an error in determining the flow rate to blow. Therefore for

in order to improve the accuracy of controlling the flow rate in the proposed device, an electronic unit between measurement units 7 and calculation 11 was additionally introduced with a block of 10 calibration coefficients, with the help of which the values of the calibration coefficients for each tuyere air duct are determined and stored. The constructive execution of the block of calibration coefficients is not critical. For example, variants are possible with the use of additional non-stationary standard means of flow measurement (for example, Pitot tubes 5) and using mathematical methods according to the measurement of pressure drops h in each of the tuyere air ducts and the total flow to blow into the blast furnace.

In the first variant, the values of the calibration coefficients are determined in the following sequence: using a non-stationary measuring device, the flow is measured through the i-th tuft meter V and simultaneously using measurement unit 7 - the value of pressure drop. Then, in block 11, the calculation

The value of the calibration coefficient K is calculated according to the formula

F

V

The values of calibration coefficients for all other tuyere air ducts are determined in the same way.

In the second variant, a multiple (at least the number of tuyere air ducts on a blast furnace) is measured simultaneously and simultaneously the total flow is blown to the blast furnace (Vg) and with the help of unit 7 for measuring the pressure drop in each tuyere air duct h. Then, in block 11, the calculation is performed to solve a system of equations of the form 2 with respect to the values of the calibration coefficients.

The values of the calibration coefficients are transmitted to the filling device of the unit 10 and are used to determine the flow rate to blow according to this method of operation of the proposed device.

Improving the reliability and accuracy of controlling the flow rate of hot blowing through the tuyeres according to the invention will improve the distribution of fuel additives (tume dust, liquid, gaseous fuels) over the tuyeres, thus stabilizing the blast furnace process and economical operation of the blast furnace. A reduction in coke consumption is expected.

Claims (1)

Claim A device for measuring the flow rate of blast in the tuyere device of a blast furnace, containing an annular air duct with a positive nozzle of general pressure, tuyere sleeves with negative nozzles, consisting of a fixed elbow and a movable stake with a point, nozzles, tuyeres, a computing unit connected to plus and minus nozzles, characterized in that, in order to increase the accuracy and simplify the device, each negative pressure take-off nozzle is built into the point of the movable knee.