CN203656971U - Residual oxygen analytic combustion control device of hot blast stove - Google Patents

Abstract

The utility model provides a residual oxygen analytic combustion control device of a hot blast stove, belongs to the technical field of the control equipment for the blast-furnace hot blast stoves and aims at implementing real-time automatic control on the combustion of the hot blast stove. The technical scheme adopted is as follows: an exhaust gas thermocouple, an arch crown thermocouple, a gas flowmeter and an air flowmeter of the residual oxygen analytic combustion control device are mounted on the hot blast stove, respectively, the signal output ends of the exhaust gas thermocouple, the arch crown thermocouple, the gas flowmeter and the air flowmeter are connected with the signal input end of a combustion controller by virtue of an isolator, a residual oxygen analyzer is mounted on the flue gas duct of the hot blast stove, and the signal output end of the residual oxygen analyzer is connected with the signal input end of the combustion controller. The residual oxygen analytic combustion control device realizes integration of residual oxygen analysis and hot blast stove combustion control, provides the optimal air-fuel ratio of the hot blast stove in a rapid burning period and provides the optimal air-fuel ratio cardinal number for next combustion process; meanwhile, the residual oxygen analytic combustion control device functions in regulating the air-fuel ratio in the combustion management period of the hot blast stove, and therefore, sufficient burning of gas is realized, the amount of the gas used by the hot blast stove is saved to an utmost extent, the combustion cost is reduced, and the environmental pollution is reduced.

Description

A hot stove residual oxygen analysis combustion control device

technical field

The utility model relates to a combustion control device for a blast furnace hot blast stove, which belongs to the technical field of blast furnace hot blast stove combustion control equipment.

Background technique

During the operation of blast furnace hot blast stove, it is necessary to effectively control the combustion of the hot blast stove through the combustion control device. At present, the main method to determine the initial air-fuel ratio of the hot blast stove combustion control device is to rely on a large amount of historical data. According to the historical vault temperature The corresponding relationship with the air-fuel ratio determines the value of the air-fuel ratio; another method is to determine the value of the initial air-fuel ratio of the combustion process according to the past combustion experience. These two methods will not be able to realize real-time and precise control of the hot blast stove combustion due to the complexity of the hot blast stove working conditions and empirical errors, resulting in problems such as poor safety and reliability, high gas consumption, and poor emission reduction effects.

Utility model content

The technical problem to be solved by the utility model is to provide a residual oxygen analysis and combustion control device for the hot blast stove, which integrates the residual oxygen analysis and the combustion control of the hot blast stove, and provides the best air-fuel ratio for the hot blast stove during the rapid combustion period , and provide the best air-fuel ratio base for the next combustion process, and at the same time play a role in adjusting the air-fuel ratio in the combustion management period of the hot blast stove, realize the full combustion of gas, save the gas consumption of the hot blast stove to the greatest extent, reduce combustion costs, and reduce environmental pollution.

The technical scheme that solves the above-mentioned technical problem is:

A combustion control device for residual oxygen analysis of a hot blast stove, which consists of a combustion controller, an isolator, an exhaust gas thermocouple, a vault thermocouple, a gas regulating valve, an air regulating valve, a gas flow meter, an air flow meter, an exhaust gas thermoelectric Couple, vault thermocouple, gas flowmeter, and air flowmeter are respectively installed on the hot blast stove, and their signal output terminals are connected to the signal input terminal of the combustion controller through an isolator. The oxygen analyzer is installed on the flue gas pipe of the hot blast stove, and the signal output end of the residual oxygen analyzer is connected with the signal input end of the combustion controller.

In the combustion control device for residual oxygen analysis of the hot blast stove, the signal output end of the combustion controller is connected to the gas regulating valve on the gas input pipeline of the hot blast stove and the air regulating valve on the air input pipeline.

The beneficial effects of the utility model are:

The utility model is an integrated controller which highly integrates the analysis of residual oxygen and the combustion control of the hot blast stove. The oxygen content in the flue gas is used as an index to control the combustion efficiency, and the setting value of the oxygen content loop controller is preliminarily set. At the average value of 0.2%, the oxygen content measured by the residual oxygen analyzer is used as the feedback value of the loop controller. The air-fuel ratio sets a reference point before each hot blast stove is fired. Around this reference point, the air-fuel ratio reference point is corrected according to the output of the oxygen loop controller. The result is used as the set value for participating in the control of the air-fuel ratio. The air-fuel ratio can be quickly, accurately and safely adjusted to the optimal value, so that the air and gas can be fully combusted, reducing the use of gas and air pollution, and achieving good economic benefits in terms of energy saving, with energy saving of more than 5%.

Description of drawings

Fig. 1 is a structural block diagram of the utility model;

Fig. 2 is a schematic structural view of the utility model.

The marks in the figure are as follows: residual oxygen analyzer 1, exhaust gas thermocouple 2, vault thermocouple 3, gas regulating valve 4, air regulating valve 5, gas flow meter 6, air flow meter 7, combustion controller 8, programmable Controller 9, isolator 10, hot blast stove 11.

Detailed ways

The composition of the utility model includes a residual oxygen analyzer 1, an exhaust gas thermocouple 2, a vault thermocouple 3, a gas regulating valve 4, an air regulating valve 5, a gas flow meter 6, an air flow meter 7, a combustion controller 8, an isolation device 10.

As shown in the figure, the exhaust gas thermocouple 2, the vault thermocouple 3, the gas flow meter 6, and the air flow meter 7 are respectively installed on the hot blast stove 11, and their signal output terminals are connected to the signal input terminals of the combustion controller 8 through the isolator 10. connect.

The function of the exhaust gas thermocouple 2 is to measure the temperature of the exhaust gas, the vault thermocouple 3 is used to measure the vault temperature, the gas regulating valve 4 is used to control the gas flow, the air regulating valve 5 is used to control the air flow, and the gas flow meter 6 is used to measure The gas flow, the air flow meter 7 is used to measure the air flow, and the function of the combustion controller 8 is to adjust the gas control valve 4 and the air control valve 5 according to the feedback data such as the vault temperature, exhaust gas temperature, and residual oxygen, and the isolator 10 is used for shunting signals.

As shown in the figure, the residual oxygen analyzer 1 is installed on the flue gas pipeline of the hot blast stove 11 , and the signal output terminal of the residual oxygen analyzer 1 is connected with the signal input terminal of the combustion controller 8 . The function of the residual oxygen analyzer is to measure the oxygen content in the flue gas.

As shown in the figure, the exhaust gas thermocouple 2, vault thermocouple 3, gas flow meter 6, and air flow meter 7 divide the signal into two through the isolator 10 and connect them to the programmable controller 9 and the combustion controller 8 respectively. The residual oxygen analyzer 1 transmits the exhaust gas residual oxygen signal to the combustion controller 8, and the programmable controller 9 communicates with the combustion controller 8, and the combustion controller 8 adjusts the gas control valve 4 and the air control valve according to the number fed back on site 5.

The working process of the present utility model is as follows:

Manually switch to "Auto Burning Furnace", click "Start Furnace Burning", the gas regulating valve 4 and air regulating valve 5 of the hot blast stove 11 start to open slowly, and stop when the gas regulating valve 4 opens to the initial gas volume, and the air regulating valve 5 according to Initial air-fuel ratio adjustment, entering the rapid combustion period, the residual oxygen analyzer 1 starts to measure the oxygen content in the flue gas. According to theoretical calculations, the oxygen content controller setting value is generally set at 0.2%, but there is a certain ripple , as long as the fluctuation is 0.0%~0.3%. In the design of the dead zone of the controller, the output of the controller does not change in the range of 0.1%~0.2%, especially if the oxygen content is less than 0.1% and the duration is less than 5s, it is considered good, and the controller does not need to act. If it continues to be less than 0.1% for more than 5s and is equal to 0.0% for more than 2s, the controller needs to act to increase the air valve to control the oxygen content to more than 0.1%. The same can be used for the judgment of oxygen content greater than 0.2%. The control system will memorize the air-fuel ratio with the oxygen content in the range of 0.1%~0.2% as the benchmark data for the next combustion, and then the combustion system will enter the vault management area and exhaust gas management area until the combustion ends.

Claims (2)

1. A combustion control device for residual oxygen analysis of a hot blast stove, which consists of a combustion controller (8), an isolator (10), an exhaust gas thermocouple (2), a vault thermocouple (3), a gas regulating valve ( 4), air control valve (5), gas flow meter (6), air flow meter (7), exhaust gas thermocouple (2), vault thermocouple (3), gas flow meter (6), air flow meter ( 7) Installed on the hot blast stove (11) respectively, their signal output terminals are connected to the signal input terminals of the combustion controller (8) through the isolator (10), the feature is that it also adds a residual oxygen analyzer ( 1), the residual oxygen analyzer (1) is installed on the flue gas pipeline of the hot blast stove (11), and the signal output terminal of the residual oxygen analyzer (1) is connected with the signal input terminal of the combustion controller (8). 2. The combustion control device for residual oxygen analysis of the hot blast stove according to claim 1, characterized in that: the signal output end of the combustion controller (8) and the gas regulating valve on the gas input pipeline of the hot blast stove (11) ( 4) Connect the air regulating valve (5) on the air input pipe.

Images