阅读说明：本技术 一种利用bprt机组调节高炉顶压的方法 (Method for adjusting top pressure of blast furnace by using BPRT (blast furnace pressure recovery turbine) unit ) 是由 暴振岭 张军红 崔继森 刘广武 毕新兴 张春茂 侯景恩 陈月光 郭瑞明 郭彦刚 于 2020-04-29 设计创作，主要内容包括：一种利用BPRT机组调节高炉顶压的方法,所述方法包括以下步骤：a.在高炉的煤气上升管上同时安装三个顶压变送器,将三个顶压变送器输出的三路顶压信号输入到BPRT机组自控系统；b.BPRT机组自控系统将接收到的三路顶压信号分别与设定的上限值和下限值进行比较,再根据比较结果对顶压信号做出选择；c.BPRT机组自控系统根据顶压信号的选定测量值和由高炉自控系统提供的顶压设定值对高炉顶压进行调控。本发明同时测量多路顶压信号并采用合理的选择顶压信号的测量值。同传统高炉顶压调控方法相比,该方法克服了单路顶压信号易丢失或不准的缺陷,可有效提高高炉顶压调控水平,确保炉顶压力的稳定性,保证高炉生产的顺利进行。(A method for adjusting top pressure of a blast furnace by using a BPRT unit comprises the following steps: a. three top pressure transmitters are simultaneously installed on a gas ascending pipe of the blast furnace, and three top pressure signals output by the three top pressure transmitters are input into a BPRT (blast furnace process control room) unit automatic control system; the BPRT unit automatic control system compares the received three paths of top pressure signals with a set upper limit value and a set lower limit value respectively, and then selects the top pressure signals according to the comparison result; and c, regulating and controlling the top pressure of the blast furnace by the automatic control system of the BPRT set according to the selected measured value of the top pressure signal and the top pressure set value provided by the automatic control system of the blast furnace. The invention simultaneously measures multiple paths of top pressure signals and reasonably selects the measured value of the top pressure signals. Compared with the traditional blast furnace top pressure regulating and controlling method, the method overcomes the defect that a single-way top pressure signal is easy to lose or inaccurate, can effectively improve the regulation and control level of the top pressure of the blast furnace, ensures the stability of the top pressure of the blast furnace, and ensures the smooth production of the blast furnace.)

1. A method for adjusting the top pressure of a blast furnace by using a BPRT unit is characterized by comprising the following steps:

a. three top pressure transmitters are simultaneously installed on a gas ascending pipe of the blast furnace, and three top pressure signals output by the three top pressure transmitters are respectively input to different input ends of a BPRT (blast furnace process control room temperature) unit automatic control system;

the BPRT unit automatic control system compares the received three jacking signals with a set upper limit value and a set lower limit value respectively, and then selects the jacking signals according to the comparison result and the following method:

if the three paths of top pressure signals are all in a normal range, namely are positioned between a set upper limit value and a set lower limit value, selecting a middle value of the three paths of top pressure signals as a selected measurement value;

if only one of the three jacking signals exceeds the normal range and the other two of the three jacking signals are in the normal range, selecting the middle value of the three jacking signals as a selected measurement value;

thirdly, if two paths of the three paths of top pressure signals exceed the normal range and the other path is in the normal range, taking the one path of top pressure signal in the normal range as a selected measurement value;

and c, regulating and controlling the top pressure of the blast furnace by the automatic control system of the BPRT set according to the selected measured value of the top pressure signal and the top pressure set value provided by the automatic control system of the blast furnace.

2. The method as claimed in claim 1, wherein when the three top pressure signals received by the BPRT unit automatic control system are all out of the normal range, the BPRT unit automatic control system discards the three top pressure signals at the same time and sets the opening of the turbine stationary blade of the BPRT unit to 50%.

3. The method for adjusting the top pressure of the blast furnace by using the BPRT unit as claimed in claim 1 or 2, wherein the top pressure set value provided by the blast furnace automatic control system to the BPRT unit automatic control system is confirmed by the following method:

the method comprises the following steps that after receiving a top pressure set value sent by a blast furnace automatic control system, a BPRT set automatic control system feeds the signal back to the blast furnace automatic control system, the blast furnace automatic control system compares the feedback signal of the top pressure set value with the sent top pressure set value after receiving the feedback signal of the top pressure set value, if the difference value of the two is smaller than a set maximum allowable error, a confirmation signal is sent to the BPRT set automatic control system, and otherwise, the confirmation signal is not sent; if the BPRT unit automatic control system receives the confirmation signal sent by the blast furnace automatic control system, the received top pressure set value is used for regulating and controlling the top pressure of the blast furnace, otherwise, the original regulating and controlling state is still maintained, and the BPRT unit automatic control system waits for receiving the top pressure set value again.

4. The method as claimed in claim 3, wherein the three top pressure signals are outputted from three top pressure transmitters, one of the top pressure signals is sent to the blast furnace automatic control system, the other top pressure signal is sent to the BPRT unit automatic control system, and the other top pressure signal is directly sent to the BPRT unit automatic control system.

5. The method as claimed in claim 4, wherein a signal abnormality alarm device is added to the BPRT unit automatic control system, and when any one of the three top pressure signals exceeds a normal range, or any two of the three top pressure signals has a deviation of more than 5KPa, or any one of the three top pressure signals has a deviation of more than 10KPa from a top pressure set value, the BPRT unit automatic control system triggers the abnormality alarm device.

Technical Field

The invention relates to a method for adjusting top pressure of a blast furnace by using a BPRT (blast furnace pressure recovery turbine) unit, which can improve the stability of the top pressure of the blast furnace and belongs to the technical field of metallurgy.

Background

In the blast furnace smelting process, whether the top pressure is stable is crucial to the blast furnace production. The BPRT unit is a coaxial driving unit of a blast furnace blower and a gas turbine, directly drives the blower by using mechanical energy output by the gas turbine, can save about 50 percent of power consumption of the blower, reduces a power generation grid connection link compared with a traditional TRT system, can more effectively recover residual pressure and residual temperature of blast furnace gas, and has the function of adjusting the pressure of the top of the blast furnace. In the process of adjusting the blast furnace top pressure by the BPRT set, the faults of a blast furnace top pressure transmitter, a short circuit or open circuit of a top pressure measuring circuit, the faults of a blast furnace automatic control system PLC module and the faults of the BPRT set automatic control system PLC module are inevitable, so that the phenomena of loss or inaccuracy of a blast furnace top pressure signal and a blast furnace top pressure set value signal are inevitable, the pressure adjusting function of the BPRT set is further lost, the blast furnace top pressure is overhigh, the gas pipeline is suppressed, or the top pressure is suddenly reduced, the smooth running of blast furnace production is influenced, great economic loss is caused to an enterprise, the gas pipeline is possibly broken in severe cases, major safety accidents such as gas leakage and the like are also possibly caused, and the maintenance of the stability of the blast furnace top pressure is especially important.

At present, a single-path top pressure signal and a single-path top pressure setting signal are commonly adopted in a domestic BPRT unit top pressure adjusting system, and a 4-20 mA signal output by an AO module of a blast furnace automatic control system PLC is transmitted to the BPRT unit automatic control system through a cable line. The control mode has poor reliability, and top pressure imbalance can be caused when module faults, line faults and transmitter faults occur, so that the stability of the pressure of the top of the blast furnace cannot be ensured.

Disclosure of Invention

The invention aims to provide a method for adjusting the top pressure of a blast furnace by using a BPRT unit aiming at the defects of the prior art so as to ensure the stability of the top pressure of the blast furnace and ensure the smooth production of the blast furnace.

The problems of the invention are solved by the following technical scheme:

a method for adjusting top pressure of a blast furnace by using a BPRT unit comprises the following steps:

a. three top pressure transmitters are simultaneously installed on a gas ascending pipe of the blast furnace, and three top pressure signals output by the three top pressure transmitters are respectively input to different input ends of a BPRT (blast furnace process control room temperature) unit automatic control system;

the BPRT unit automatic control system compares the received three jacking signals with a set upper limit value and a set lower limit value respectively, and then selects the jacking signals according to the comparison result and the following method:

if the three paths of top pressure signals are all in a normal range, namely are positioned between a set upper limit value and a set lower limit value, selecting a middle value of the three paths of top pressure signals as a selected measurement value;

if only one of the three jacking signals exceeds the normal range and the other two of the three jacking signals are in the normal range, selecting the middle value of the three jacking signals as a selected measurement value;

thirdly, if two paths of the three paths of top pressure signals exceed the normal range and the other path is in the normal range, taking the one path of top pressure signal in the normal range as a selected measurement value;

and c, regulating and controlling the top pressure of the blast furnace by the automatic control system of the BPRT set according to the selected measured value of the top pressure signal and the top pressure set value provided by the automatic control system of the blast furnace.

According to the method for adjusting the top pressure of the blast furnace by using the BPRT unit, when three top pressure signals received by the BPRT unit automatic control system exceed a normal range, the BPRT unit automatic control system abandons the three top pressure signals at the same time, and the opening of the turbine stationary blade of the BPRT unit is set to be 50%.

In the method for adjusting the top pressure of the blast furnace by using the BPRT unit, the top pressure set value provided by the blast furnace automatic control system to the BPRT unit automatic control system needs to be confirmed according to the following method:

the method comprises the following steps that after receiving a top pressure set value sent by a blast furnace automatic control system, a BPRT set automatic control system feeds the signal back to the blast furnace automatic control system, the blast furnace automatic control system compares the feedback signal of the top pressure set value with the sent top pressure set value after receiving the feedback signal of the top pressure set value, if the difference value of the two is smaller than a set maximum allowable error, a confirmation signal is sent to the BPRT set automatic control system, and otherwise, the confirmation signal is not sent; if the BPRT unit automatic control system receives the confirmation signal sent by the blast furnace automatic control system, the received top pressure set value is used for regulating and controlling the top pressure of the blast furnace, otherwise, the original regulating and controlling state is still maintained, and the BPRT unit automatic control system waits for receiving the top pressure set value again.

The method for adjusting the top pressure of the blast furnace by using the BPRT unit comprises the steps of outputting three top pressure signals by three top pressure transmitters, wherein one top pressure signal is sent to a blast furnace automatic control system firstly, then sent to the BPRT unit automatic control system by the blast furnace automatic control system, and the other two top pressure signals are directly sent to the BPRT unit automatic control system.

The method for adjusting the top pressure of the blast furnace by using the BPRT unit is characterized in that a signal abnormity alarm device is added in an automatic control system of the BPRT unit, and when any one of three top pressure signals exceeds a normal range, or the deviation between any two of the three top pressure signals exceeds 5KPa, or any one of the three top pressure signals deviates from a top pressure set value by more than 10KPa, the automatic control system of the BPRT unit triggers the abnormity alarm device.

The invention simultaneously measures a plurality of paths of top pressure signals, eliminates abnormal values by adopting a reasonable selection method and determines the measured value of the top pressure signals. Compared with the traditional blast furnace top pressure regulating and controlling method, the method overcomes the defect that a single-way top pressure signal is easy to lose or inaccurate, can effectively improve the regulation and control level of the top pressure of the blast furnace, ensures the stability of the top pressure of the blast furnace, and ensures the smooth production of the blast furnace.

The invention effectively avoids the phenomenon of incontrollable top pressure regulation caused by distortion of the top pressure set value by optimizing the selection mode of the top pressure set signal, and further improves the regulation level of the top pressure of the blast furnace.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings.

FIG. 1 is a schematic illustration of a BPRT plant installation;

fig. 2 is a flow chart of the process for optimizing signals of the blast furnace top pressure control system according to the invention.

The reference numbers in the figures are: 1. the method comprises the following steps of (1) a blast furnace, 2, a gas ascending pipe, 3, gravity dust removal, 4, cloth bag dust removal, 5, a high-pressure gas pipeline, 6, a BPRT unit, and 7, a low-pressure gas pipeline.

Detailed Description

The invention provides a method for adjusting the top pressure of a blast furnace by using a BPRT unit, which effectively overcomes the phenomenon of incontrollable top pressure adjustment caused by easy distortion of a single signal source by improving the top pressure signal of the blast furnace and the selection mode of a top pressure set value, and solves the problems in the background art.

Compared with the traditional method, the method has the following characteristics:

optimizing three blast furnace top pressure signals accessed by a BPRT unit automatic control system;

2. optimizing the acquisition mode of the top pressure signal;

3. program screening is carried out on the top pressure process value;

4. optimizing a connection signal between a blast furnace automatic control system and a BPRT unit automatic control system;

5. taking confirmation measures for the set value of the top pressure;

6. and a signal abnormity alarm device is added.

Referring to fig. 1 and 2, the optimization of blast furnace top pressure signals accessed by the BPRT unit automatic control system to three means that three jacking pressure transmitters are installed on a gas ascending pipe 2 of a blast furnace 1, wherein one jacking pressure signal (jacking pressure PV) is introduced into the blast furnace automatic control system, and the blast furnace automatic control system provides a power supply required by the pressure transmitter; introducing other two jacking signals (jacking PV2 and jacking PV3) into the automatic control system of the BPRT unit, and providing a power supply required by the pressure transmitter by the automatic control system of the BPRT unit; and outputting a 4-20 mA signal (jacking PV1) from a jacking signal received by the blast furnace automatic control system through an AO module, and transmitting the jacking PV1 to a BPRT unit automatic control system through a cable line.

The optimization of the collection mode of the top pressure signal means that the top pressure signal (top pressure PV1) from the AO module of the blast furnace automatic control system received by the BPRT machine set automatic control system and two paths of top pressure signals (top pressure PV2 and top pressure PV3) from the blast furnace gas ascending pipe are respectively connected into three different AI modules (AI module 1, AI module 2 and AI module 3) of the BPRT machine set automatic control system, so that all top pressure signal abnormalities caused by single module faults are prevented.

The step of program screening for the top pressure process value refers to the step of compiling an automatic judgment and selection program aiming at three paths of top pressure signals measured by a top pressure transmitter: 1) if the three paths of top pressure signals are normal, namely the three paths of top pressure signals are all positioned between the set upper limit value and the set lower limit value, automatically selecting the middle value in the three paths of top pressure signals as a measured value; 2) when one of the top pressure signals is abnormal (is larger than the upper limit value or smaller than the lower limit value), the middle value is still automatically selected as a measured value, and the authenticity of the adopted top pressure measured value is ensured; 3) when the measured values of the two top pressure signals are abnormal, the two top pressure signals are judged to be simultaneously failed, and the other normal top pressure signal closest to the top pressure set value is automatically selected as the measured value by the program; 4) in extreme cases, all three jacking signals fail, emergency measures need to be taken, at the moment, the opening degree of the turbine stationary blade of the BPRT set is set to be 50%, the gas pipe network and equipment are ensured to be in a safe pressure range, and the jacking signal selection rule is shown in table 1.

Table 1: selection rule of top pressure signal

Optimizing a link signal between the blast furnace automatic control system and the BPRT unit automatic control system means that after a top pressure set value is still set by a blast furnace working length, the top pressure set value is output through an AO module of the blast furnace automatic control system (SV is set by top pressure, and a 4-20 mA signal is transmitted to the BPRT unit automatic control system through a cable line; after optimization, a path of output signal (top pressure setting feedback SV _ F) is added in the BPRT unit automatic control system, and a top pressure setting value signal received from the blast furnace automatic control system is transmitted back to the blast furnace automatic control system to form a closed loop. Meanwhile, a digital output signal is added in a DO module of the blast furnace automatic control system and is transmitted to a Digital Input (DI) module of the BPRT machine set automatic control system through relay conversion and a cable line to be used as a top pressure set value confirmation signal.

The confirmation measure of the top pressure set value is that when the blast furnace operator inputs the top pressure set value (top pressure set SV) through the operation picture, the value will not take effect immediately, but pop up a dialogue window picture, the picture displays the set value (top pressure set feedback SV _ F) to be taken effect transmitted from the BPRT machine set automatic control system, if the difference between the top pressure set SV and the top pressure set feedback SV _ F value is not more than 1Kpa, the two values are judged to be consistent, the confirmation can be clicked, and a confirmation signal is sent to the BPRT machine set automatic control system to complete the top pressure setting.

The addition of the signal abnormity alarm device means that a special alarm is added, when an abnormal condition occurs in any one of the three jacking signals, or the mutual deviation between the three jacking signals exceeds 5KPa, or the measured value of the jacking signal deviates more than 10KPa from the set value of jacking pressure, the alarm function is triggered, and the operators at the post of the BPRT set can adjust or feed back the information to relevant departments for maintenance and process adjustment in time.

The invention effectively avoids the phenomenon of incontrollable top pressure regulation caused by easy distortion of a single signal source for top pressure measurement and top pressure setting by programming a controller program, dispersing signal acquisition, improving an operation picture, optimizing a top pressure signal and setting a signal selection mode, and solves the problems in the background art. Even if a single signal loop has a problem, the normal work of the BPRT unit can not be influenced, the related equipment can be inspected and maintained under the condition of not influencing production, the reliability of the BPRT unit for adjusting the top pressure of the blast furnace is improved, and the economic benefit and the safety benefit are fully improved.