SU391180A1 - VPTB - Google Patents

Description

one

This invention relates to ferrous metallurgy, in particular, to methods for controlling gas pressure under the blast furnace throat.

There are known methods for regulating the pressure of a gas beneath the top of a blast furnace in the presence of a gas reclamation pressure-free turbine (GUBT) on it, which is carried out by acting on an isodromic pressure regulating gas regulator on the throttle body of a special throttling device — a throttle group through which the MHG passes through a GHG gas flow through the throttle body through a throttling device — a throttle group through which the MHD flow is passed. amount of domestic gas south.

A throttle group is a set of throttle valves of different diameters. One of them, the regulator, is controlled by an isodromic pressure regulator. The rest of the dampers, as a rule, of a larger diameter than the adjusting one, are remotely controlled, while KaiK and the regulator GUTT are rotatable. When the controller is operating, the remote-controlled throttle bodies do not change their position.

In order to maintain a constant pressure under the top of the blast furnace, short-term technological disturbances from the furnace (usually connected with the charging device operation) through the throttle control valve at each steady-state mode must not allow the flow of the pelvis to be less than Рдр to enter the furnace. mip Gas flow Qr. m. through the utilization turbine is determined by the pressure and temperature of the gas is not rare, and the value of the leakage flow is Rdr. pog 4eipe3 looseness of the Drosseliga group - with a blast furnace gas under the furnace top. With a total yield of blast furnace gas QoGm. fair equation. Miiii. Qo6in.-

-Qr. T.-Q; i.p. log

In the case when, with an increase in the output of the blast furnace gas caused by changes in the furnace process, the right part of the equation significantly exceeds the left, in order to restore the pressure under the throat it is necessary to open large, remotely moved throttle valves. If the output of the blast furnace gas cyniecTno decreases, then for the entire period of work with a reduced gas output it is necessary to cover the turning diaphragm of the main tube by an amount so that through the adjusting throttle the drohadil gas Rdr. think

So, the known systems are not fully automatic, since with changes in the output of the blast furnace gas, it is necessary to distantly move the throttle valves or the diaphragm of the main tube. In addition, in some cases, to pass through the throttle group of the minimum necessary for the needs of controlling the flow rate of the blast furnace gas, the gas flow through the HBT is throttled, which, in turn, leads to a decrease in the electricity generation of the utilization turbine.

The aim of the invention is to ensure maximum gas flow through the HBT.

This is achieved by the fact that the isodromic regulator, the sensitive element of which measures the gas pressure under the blast furnace top furnaces, sequentially controls three regulating elements — two regulating elements “throttle valves of the throttle group and”. rotary diaphragm tube. When the pressure of the gas decreases, the transfer of the control valve from the first valve to the second and then from the second to the rotary diaphragm of the main tube is carried out by a signal (for example, a limit switch) that the corresponding regulator has moved to the maximum suitable for conditions normal operation value (this prevents sticking of the dampers in the minimum covered state, etc.).

The proposed method, along with the full automation of the process of maintaining a constant pressure of the blast-furnace gas under the blast furnace throat, ensures the maximum possible generation of electric energy by a utilization turbine at any given output of the blast-furnace gas, since the reduction of the top gas flow through the main gas pipeline is carried out only after all throttle valves are completely covered throttle group.

The drawing shows a control device that implements the proposed method.

The isodromic regulator 1 of its measuring element 2 measures the gas pressure under the throat, compares it with the task set by setpoint 3, and the imbalance signal directs the logic device 4. It transmits the control action of the regulator to one of the three regulating and regulating throttle the valve 5 (450 mm), the adjusting throttle valve 6 (300 mm) or the rotary diaphragm 7. The logic device 4 also receives signals about the position of the regulators. Depending on the combination of these signals, the control action of the regulator is transferred from one organ to another. To generate the aforementioned signals from the regulating bodies, it is equipped with limit switches: the throttle valve 5 is equipped with a switch 8, which gives a signal about its maximum cover; Throttle valve 6 - by switches 9 and 10, signaling its full opening and maximum cover, and, finally, turning the diaphragm of HUBT - switch 11, giving a signal of its full opening.

In order to reduce the output of the blast furnace gas or the pressure drop under the furnace top, the device 4 operates as follows.

When signals are received about the full opening of the rotary diaphragm 7 and the valve 6, the control action of the regulator is transmitted to the valve 5. After it is completely covered while maintaining a constant gas pressure, the switch 8 closes under the control panel, after which the control action of the regulator is transferred valve 6. After opening the contact of the switch of the valve 9, the throttle valve 5 is fixed in the fully closed position. Fully covering the valve 6 causes the contact of the switch 10 to close, after which the control action of the regulator is transferred to the rotary diaphragm 7. After the contact of its switch 11 is opened, the throttle valve 6 is fixed in the fully closed position and until the diaphragm completely opens takes

With an increase in the blast furnace gas output and an increase in pressure under the top of the furnace, the rotary diaphragm of the main tube and throttle valves of the throttle group open in the reverse order.

Subject invention

The method of controlling the gas pressure under the blast furnace thrust, including the effect of high pressure inductors on the pipelines and the diaphragm of the gas utilization uncompressed turbine (HBT), characterized in that, in order to ensure maximum gas flow through the HBT, the gas pressure regulator under the throat is sequentially switched over the signal to completely close the throttles in the gas pipeline after the scrubber to the diaphragm of the main current transformer, and the reverse switching of the regulator is carried out according to the signal of the end switch of the main main switch.