CN101892338A - Constant air temperature control system for hot blast stove - Google Patents

Abstract

A constant air temperature control system for a hot blast stove, comprising a hot blast stove (2), a detection element, a regulating valve, a data collector (1) and a computer (26), including fluid parameter and valve position signal detection, data acquisition, data transmission, Data comparison, data correction and control adjustment process; installation of detection elements and regulating valves in pipelines, installation of temperature measurement devices on the surface of furnace body, dynamic calculation of parameters such as checker brick heat storage, temperature rise rate and theoretical wind temperature during combustion, online adjustment of combustion air and Gas flow, preheating temperature and other parameters are used to control the reversing of the hot blast stove with the maximum set temperature of the checker brick, furnace roof and flue gas. During the air supply period, the air supply curve and the air supply time are determined with the goal of hot air temperature control. This method is based on the calculation of the dynamic balance of the online energy of the hot blast stove, effectively controls the heat storage of the checker bricks of the hot blast stove, adjusts the air supply volume and the air supply time, and ensures the stable output of the hot blast stove air temperature.

Description

Constant wind temperature control system for hot blast stove

Technical field

The invention belongs to Iron And Steel Industry iron-smelting blast furnace hotblast stove control techniques field, particularly relate to a kind of wind-warm syndrome Controlling System, use under the situation of stablizing wind-warm syndrome at blast furnace and use.

Background technology

Hotblast stove is the auxiliary facility of blast furnace, and its effect is to provide stable wind-warm syndrome for blast furnace.The operating parameter of hotblast stove is a lot, and parameters such as temperature, pressure, flow are arranged, and simultaneously, hotblast stove comprises burning, changes processes such as stove and air-supply, and operating parameter control and process control how to carry out effective hotblast stove are the keys of hotblast stove control.

At present, control about hotblast stove mainly contains following mode, according to the control mode branch, can be divided into one-level control, secondary control etc., wherein one-level is controlled to be the logic control such as the monitoring such as instrument, PLC on basis, secondary is controlled to be control of process control such as automatic combustion and expert systems etc., and three grades are controlled to be production control level and production management level with level Four, as the ERP system of enterprise.Present hot blast stove system automated control technology relates generally to one-level control, secondary control.

Secondary control about hotblast stove, mainly contain automatic combustion control system at present based on mathematical model, it is characterized in that with the incendiary optimal air-fuel ratio be the adjusting that hotblast stove operating parameter and process are carried out in the basis, can effectively solve the efficiency of combustion and the optimization problem of hotblast stove, but have the stable and constant problem that effectively to control wind-warm syndrome.Stablize wind-warm syndrome for guaranteeing that blast furnace uses, often adopt mixed wind to regulate, and the instability of mixer selector valve door aperture changes the instability that causes blast furnace to use wind-warm syndrome.

Fan Chengfei proposes the hotblast stove autocontrol method, referring to " Shanxi metallurgy " 2008 4 phase 51-55 pages or leaves, it mainly is target with the dome temperature, keep the blast furnace gas flow constant, set the rate of descent of coke-oven gas and blast furnace gas ratio, to reduce the coke-oven gas flow, reach the control of COG in the Combustion of Hot Air Furnace.

Patent of invention 200410000677.1, Ma Zhuwu etc. propose a kind of hybrid blast funnace hot blast stove optimizing and controlling method, adopt computer system, developing instrument, functional module comprises modules such as data gathering, physical model, artificial intelligence model, mixture model, output control, and realization is optimized control to the fuel quantity and the air capacity of the input of hotblast stove heating.

Patent of invention 200510127964.3, Sun Jinsheng etc. propose a kind of harmonization control method for blast furnace hot blast stove system, according to the time of example prediction hotblast stove air-supply, determine the combustion time of current incendiary hotblast stove with this, and the size of fuel metering in view of the above, original fixed cycle burning is become the variable cycle burning.

Patent of invention 200810102200.2, the automatic control system of the blast furnace hot blast stove combustion process that Wang Ziting etc. propose from solving the full automatic control of combustion processes, realizes that nobody starts with in intervention, the method that adopts self study and fuzzy control to combine, the full automatic control of realization Combustion of Hot Air Furnace process.

Above method stresses the Automatic Combustion control of hotblast stove, all can't realize the stable control of wind-warm syndrome.

Patent of invention 96105254.6, Zhou Yaochang has proposed off-line control method for hot-blast stove operation, adopt the heat calculation of regenerator lattice brick, adopt proximate calculation regenerator heat-conduction coefficient, this method only off-line provides foundation for stove operation, because the variation of actual regenerator heat-conduction coefficient so can't realize the stable control of online wind-warm syndrome.

Summary of the invention

The object of the present invention is to provide a kind of Control System of Airheater that is controlled to be the basis based on wind-warm syndrome, adopt control hotblast stove different sites method of temperature, on the monitoring basis of furnace roof, checker brick and tail flue gas equitemperature, determine parameters such as the space gas under the constant wind-warm syndrome, cold and hot wind flow, temperature by the hotblast stove heat balance principle, and, realize the stable control of hotblast stove wind-warm syndrome by online adjusting.Overcome the unsettled defective of present hotblast stove wind-warm syndrome, improve the wind-warm syndrome automatic control system of hotblast stove, combine with advanced control techniquess of part such as hotblast stove automatic combustion or expert systemss, reach the stable control of hotblast stove wind-warm syndrome in use.

A kind of constant wind temperature control system for hot blast stove, comprise hotblast stove, gas line, combustion air pipeline, cold air duct, hot air duct, flue, data acquisition unit and computer, it is characterized in that: control process comprises fluid parameter and valve position signal detection, data gathering, data transmission, data contrast, data correction and regulating and controlling process, comprises following steps:

(1) gas parameters that detects according to the burning phase, combustion air parameter, Gas Parameters are calculated checker brick heat storage capacity, temperature rise rate and theoretical wind-warm syndrome, and wherein parameter comprises temperature, pressure and flow;

(2) compare with setting wind-warm syndrome according to the actual outlet wind-warm syndrome that on air detects, revise the calculating of the theoretical wind-warm syndrome that exceeds setting range, adjust gas parameters, combustion air parameter, the Gas Parameters of burning phase;

(3) according to the furnace roof, checker brick and the funnel temperature that detect respectively with the maximum of computer settings relatively, surpass furnace roof, checker brick and the funnel temperature maximum set, the commutation of control hotblast stove;

(4) according to the cold wind and the hot blast parameter that on air detect, calculate temperature drop rate, air output and air-supply time, adjust cold wind, hot air flow according to setting wind-warm syndrome;

(5) adopt intersection mid-shunt pattern control hotblast stove group to change stove.

Constant wind temperature control system for hot blast stove of the present invention, gas line is installed gas parameters measuring element and gas regulator, the combustion air pipeline is installed combustion air parameter detecting element and combustion air variable valve, cold air duct is installed cold wind parameter detecting element and cold wind variable valve, flue is installed Gas Parameters measuring element and flue variable valve, hot air duct is installed hot blast parameter detecting element and hot blast variable valve, the hotblast stove furnace roof is installed by the furnace roof infrared temperature measurement apparatus and checker brick top infrared temperature measurement apparatus is installed at the checker brick top, thermocouple temperature measuring apparatus is installed in the checker brick bottom, hot-blast furnace body surface mounting surface wireless temperature measuring device; Wherein, gas parameters measuring element, combustion air parameter detecting element, cold wind parameter detecting element, Gas Parameters measuring element, hot blast parameter detecting element comprise flow, pressure and temperature transmitter; Gas parameters measuring element, gas regulator, combustion air parameter detecting element, combustion air variable valve, cold wind parameter detecting element, cold wind variable valve, Gas Parameters measuring element, flue variable valve, hot blast parameter detecting element, hot blast variable valve, furnace roof infrared temperature measurement apparatus, checker brick top infrared temperature measurement apparatus, thermocouple temperature measuring apparatus, surperficial wireless temperature measuring device link to each other with data acquisition unit by wired or wireless data conveyer line, and data acquisition unit gathers detection signal and transmits burning and the air-supply process monitoring that computer carries out hotblast stove.

Constant wind temperature control system for hot blast stove of the present invention, in the burning phase, by the gas parameters measuring element, combustion air parameter detecting element, the flow that the Gas Parameters measuring element detects, temperature, pressure and by the furnace roof infrared temperature measurement apparatus, checker brick top infrared temperature measurement apparatus, thermocouple temperature measuring apparatus, the throat temperature that the surface wireless temperature measuring device detects, checker brick temperature and body of heater surface temperature, the online computed in software of machine goes out the checker brick heat storage capacity as calculated, temperature rise rate and theoretical wind-warm syndrome, and adopt actual outlet wind-warm syndrome to revise, compare by corrected Calculation wind-warm syndrome and setting wind-warm syndrome, to exceeding the corrected Calculation wind-warm syndrome of setting the wind-warm syndrome scope, adjust gas regulator aperture and combustion air control valve opening and gas temperature and combustion air preheating temperature by computer, thereby realize gas flow, gas temperature and combustion air flow, the adjustment of combustion air temperature; When the flow that detects, the variation of pressure and temperature parameter, use the constant principle of wind-warm syndrome, corresponding each detect parameters of regulating; When combustion time, furnace roof top temperature, checker brick head temperature, when the tail flue gas temperature exceeds set(ting)value, changing-over stove;

Hotblast stove uses coal gas and adopts fully burning blast-furnace gas, specifically may further comprise the steps:

(1) gas flow, gas pressure, gas temperature, combustion air flow, combustion air pressure, combustion air temperature, parameter detecting such as flue gas flow, tail flue gas temperature,

(2) combustion time, furnace roof top temperature, checker brick head temperature, waste gas funnel temperature are set,

1. be 40～110min combustion time;

2. the furnace roof top temperature is 1400～1450 ℃;

3. the checker brick head temperature is 1250～1350 ℃;

4. the tail flue gas temperature is 200～400 ℃;

(3) checker brick heat storage capacity, temperature rise rate and the isoparametric calculating of theoretical wind-warm syndrome,

1. the checker brick heat storage capacity is calculated,

$Q_z={\∫}_0^{\mathrm{\τ}}{\mathrm{dC}}_z{\mathrm{dM}}_z{\mathrm{dT}}_z/\mathrm{d\τ}$

In the formula: Q _z-checker brick heat storage capacity, kJ, C _z-checker brick thermal capacitance, kJ/ (kg. ℃); M _z-checker brick quality, kg; T _z-checker brick temperature, ℃; τ-time, s;

2. the checker brick temperature rise rate calculates,

$\mathrm{dS}=\frac{{\mathrm{dT}}_z}{\mathrm{d\τ}}$

In the formula: the S-temperature rise rate, ℃/s;

3. theoretical wind-warm syndrome is calculated,

$T_f=\frac{V_g(Q_{\mathrm{dw}}+C_g{T}_g+k{C}_a{T}_a)-Q_s}{C_f{V}_f}$

In the formula: Q _DwThe lower heating value of-coal gas, kJ/m ³C _g-coal gas thermal capacitance, kJ/ (m ³. ℃); V _g-blast furnace gas volumetric flow rate, m ³/ s; T _g-gas preheating temperature, ℃; C _a-combustion air thermal capacitance, kJ/ (m ³. ℃); V _a-combustion air volume, m ³T _a-combustion air preheating temperature, ℃; C _f-hot blast thermal capacitance, kJ/ (m ³. ℃); V _f-hot blast volumetric flow rate, m ³/ s; T _f-theoretical wind-warm syndrome, ℃; The k-air-fuel ratio, 0.6～0.7; Q _s-hotblast stove thermosteresis, kJ;

(4) adjust the checker brick temperature rise rate according to checker brick temperature rise rate estimation combustion time or according to changing the stove time, and then adjust blast furnace gas flow and combustion air flow,

(5) revise the calculating that exports wind-warm syndrome,

T _fs＝ξT _f

T _Fs-actual wind-warm syndrome, ℃; ξ-correction factor;

(6) revise gas preheating temperature and combustion air preheating temperature,

(7) gas parameters of testing process, combustion air parameter fluctuation are taked reverse adjusting, and caloric power of gas fluctuation forward is regulated air-fuel ratio,

1. gas pressure, gas flow, gas temperature fluctuation surpass 2%～5%, oppositely regulate 2%～5%;

2. combustion air pressure, combustion air airshed, combustion air temperature fluctuation surpass 2%～5%, oppositely regulate 2%～5%,

3. the caloric power of gas fluctuation surpasses 2%～5%, and forward is regulated air-fuel ratio 2%～5%,

(8) combustion time, design temperature go beyond the scope, and the burning phase finishes, changing-over stove.

In on air, by flow, temperature, the pressure of cold wind parameter detecting element, hot blast parameter detecting element testing and throat temperature, checker brick temperature and the body of heater surface temperature that detects by furnace roof infrared temperature measurement apparatus, checker brick top infrared temperature measurement apparatus, thermocouple temperature measuring apparatus, surperficial wireless temperature measuring device, utilize checker brick heat storage capacity and wind-warm syndrome data, calculate checker brick temperature drop rate and air output, adjust cold wind control valve opening or hot blast control valve opening by computer, finish the adjustment of cold wind and hot air flow, thereby reach the stable control of hot-blast outlet temperature; When air-supply time, hotblast stove temperature out are lower than the wind-warm syndrome control accuracy scope of setting, changing-over stove;

The air-supply control process specifically may further comprise the steps:

(1) cold wind parameter, hot blast parameter, parameter detecting such as checker brick head temperature and bottom temp, body of heater surface temperature;

(2) wind-warm syndrome control accuracy scope for set wind-warm syndrome ± 4 ℃,

(3) utilize checker brick heat storage capacity, checker brick temperature drop rate estimation air-supply time,

(4) air output calculates and control,

$V_f=\frac{Q_z}{C_{\mathrm{fs}}{T}_{\mathrm{fs}}}$

In the formula: Q _z-checker brick heat storage capacity, kJ; T _Fs-actual wind-warm syndrome, ℃; C _Fs-hot blast thermal capacitance, kJ/ (m ³. ℃);

Wind-warm syndrome descends 2 ℃, turns down hot blast variable valve (4) and cold wind variable valve (31) aperture 1%;

(5) parameter such as air-supply time, setting wind-warm syndrome goes beyond the scope, and on air finishes changing-over stove.

Constant wind temperature control system for hot blast stove of the present invention, the hotblast stove group is by hotblast stove A, hotblast stove B and hotblast stove C form, gas main and hotblast stove A gas line, hotblast stove B gas line links to each other with hotblast stove C gas line, combustion air house steward and hotblast stove A combustion air pipeline, hotblast stove B combustion air pipeline links to each other with hotblast stove C combustion air pipeline, breadboard and hotblast stove A flue, hotblast stove B flue links to each other with hotblast stove C flue, cold wind house steward and hotblast stove A cold air duct, hotblast stove B cold air duct links to each other with hotblast stove C cold air duct, hot-blast main and hotblast stove A hot air duct, hotblast stove B hot air duct links to each other with hotblast stove C hot air duct; The valve position signal of hotblast stove A gas stop valve, hotblast stove A combustion air trip valve, hotblast stove A flue trip valve, hotblast stove A cold wind trip valve, hotblast stove A hot blast trip valve imports computer into by data acquisition unit and carries out opening and closing control; The valve position signal of hotblast stove B gas stop valve, hotblast stove B combustion air trip valve, hotblast stove B flue trip valve, hotblast stove B cold wind trip valve, hotblast stove B hot blast trip valve imports computer into by data acquisition unit and carries out opening and closing control; The valve position signal of hotblast stove C gas stop valve, hotblast stove C combustion air trip valve, hotblast stove C flue trip valve, hotblast stove C cold wind trip valve, hotblast stove C hot blast trip valve imports computer into by data acquisition unit and carries out opening and closing control; Intersection mid-shunt pattern is adopted in burning and air-supply, and computer changes stove by identical timed interval intersection control, and the ratio of the timed interval with the air-supply cycle is 1/2～3/4.

So burning repeatedly, air-supply circulation and the mid-shunt control that intersects realize the stable of hot air furnace hot air temperature.

This method is based upon hotblast stove and calculates on the basis in the transient equilibrium of heat input, effectively control the combustion air of Combustion of Hot Air Furnace phase, the input heat and the checker brick heat storage capacity of gas-fired, adjust by on air interior air output and air-supply time, guarantee the stable output of hotblast stove wind-warm syndrome.

Constant wind temperature control system for hot blast stove of the present invention has following advantage:

The monitoring of 1 hotblast stove operating parameter and regulatory function

In present case, not only can realize flow, the pressure and temperature monitoring of tubing systems such as hotblast stove combustion air, coal gas, cold wind, hot air duct and flue, and can be by the adjustment of computer realization flow and pressure.

2 checker brick heat storage capacity and isoparametric dynamic calculation of temperature rise rate and optimization of operating parameters function

Utilize online dynamic monitoring data, by system's energy input and output equilibrium principle and corrected Calculation wind-warm syndrome with parameter such as wind-warm syndrome is set, the combustion system of rapid adjustment hotblast stove and blowing system are realized the optimization of operating parameter.

3 control processs simple and rapid

Be controlled to be basic foundation with wind-warm syndrome, controlled variable quantity is simplified greatly, utilizes the theoretical heat transfer model computational short cut of online corrected Calculation than checker brick.

4 is safe and reliable, and wind-warm syndrome is stable

With checker brick head temperature and throat temperature is that the highest controlled temperature and the hot-blast outlet temperature of commutation is controlled target, can guarantee to export the stable and safety of wind-warm syndrome.

Description of drawings

Below in conjunction with accompanying drawing the specific embodiment of the present invention is described further.

Fig. 1 is a Controlling System synoptic diagram of the present invention;

Fig. 2 is a wind-warm syndrome control flow synoptic diagram of the present invention;

Fig. 3 and Fig. 4 are hotblast stove group system schematic flow sheet of the present invention.

Among the figure, 1, data acquisition unit, 2, hotblast stove, 3, hot-blast outlet, 4, the hot blast variable valve, 5, hot blast parameter detecting element, 6, hot air duct, 7, combustion air parameter detecting element, 8, the combustion air variable valve, 9, the combustion air pipeline, 10, gas regulator, 11, gas line, 12, the gas parameters measuring element, 13, the combustion air inlet, 14, gas entry, 15, checker brick, 16, flue outlet, 17, cold air inlet, 18, the flue variable valve, 19, the Gas Parameters measuring element, 20, flue, 21, cold air duct, 22, cold wind parameter detecting element, 23, the furnace roof infrared temperature measurement apparatus, 24, the data conveyer line, 25, checker brick top infrared temperature measurement apparatus, 26, computer, 27, the surface wireless temperature measuring device, 28, thermocouple temperature measuring apparatus, 29, gas blower, 30, the cold wind trip valve, 31, the cold wind variable valve, 32, hotblast stove A hot air duct, 33, hotblast stove A hot blast trip valve, 34, hotblast stove A hot blast variable valve, 35, hotblast stove A, 36, hotblast stove A combustion air variable valve, 37, hotblast stove A gas regulator, 38, hotblast stove A gas stop valve, 39, hotblast stove A combustion air trip valve, 40, hotblast stove A gas line, 41, hotblast stove A combustion air pipeline, 42, hotblast stove A flue variable valve, 43, hotblast stove A flue trip valve, 44, hotblast stove B hot air duct, 45, hotblast stove C hot air duct, 46, the hot-blast main, 47, hotblast stove A flue, 48, hotblast stove B flue trip valve, 49, hotblast stove B flue, 50, hotblast stove C flue trip valve, 51, hotblast stove C flue, 52, breadboard, 53, hotblast stove B hot blast trip valve, 54, hotblast stove B, 55, hotblast stove B flue variable valve, 56, hotblast stove C flue trip valve, 57, hotblast stove C, 58, hotblast stove C flue variable valve, 59, chimney, 60, hotblast stove B hot blast variable valve, 61, hotblast stove B combustion air variable valve, 62, hotblast stove B gas regulator, 63, hotblast stove B gas stop valve, 64, hotblast stove B combustion air trip valve, 65, hotblast stove A cold wind variable valve, 66, hotblast stove A cold wind trip valve, 67, hotblast stove A cold air duct, 68, gas main, 69, hotblast stove B combustion air pipeline, 70, hotblast stove B gas line, 71, the combustion air house steward, 72, hotblast stove C hot blast variable valve, 73, hotblast stove C combustion air variable valve, 74, hotblast stove C gas regulator, 75, hotblast stove C gas stop valve, 76, hotblast stove C combustion air trip valve, 77, hotblast stove B cold wind variable valve, 78, hotblast stove B cold wind trip valve, 79, hotblast stove B cold air duct, 80, the cold wind house steward, 81, hotblast stove C combustion air pipeline, 82, the combustion air gas blower, 83, hotblast stove C cold wind variable valve, 84, hotblast stove C cold wind trip valve, 85, hotblast stove C cold air duct, 86, hotblast stove C gas line, 87, the combustion air primary heater unit, 88, the gas preheating device.

Embodiment

Constant wind temperature control system for hot blast stove embodiment of the present invention is as follows.With a hotblast stove and three hotblast stove groups is that embodiment describes whole process in detail, and the significant parameter of the hotblast stove that present embodiment is selected for use is:

Hotblast stove quantity: 3

Combustion system: two burn one send

Hotblast stove type: internal combustion type

Fuel type: blast furnace gas

Combustion period: 60min

The air-supply time: 50min

Wind-warm syndrome: 1265 ± 4 ℃

Combustion of Hot Air Furnace air-supply controlled variable setting range sees Table 1,

Table 1 Combustion of Hot Air Furnace air-supply controlled variable setting range:

As shown in figures 1 and 3, in the burning phase, coal gas enters in the stove through gas regulator 10, gas parameters measuring element 12 and the gas entry 14 of gas line 11, gas parameters measuring element 12 data detection signals, data signal comprises flow, pressure and temperature, import computer 26 into through data acquisition unit 1, regulate gas regulator 10 apertures by the control data of computer 26 through data acquisition unit 1, thereby realize the adjustment of gas flow, pressure; Combustion air enters in the stove through combustion air variable valve 8, combustion air parameter detecting element 7 and the combustion air inlet 13 of combustion air pipeline 9, combustion air parameter detecting element 7 data detection signals import computer 26 into through data acquisition unit 1, control data by computer 26 is regulated combustion air variable valve 8 apertures through data acquisition unit 1, thereby realizes the adjustment of combustion air flow, pressure; The preheating temperature of combustion air and coal gas is adjusted by combustion air primary heater unit 87 and gas preheating device 88 and is realized; Flue gas is discharged through flue variable valve 18, the Gas Parameters measuring element 19 of flue outlet 16, flue 20, Gas Parameters measuring element 19 data detection signals are through data acquisition unit 1, input computer 26, control data by computer 26 is adjusted the aperture of flue variable valve 18 through data acquisition unit 1, thereby realizes the adjustment of flue gas flow, pressure; Temperature and tail flue gas temperature through furnace roof infrared temperature measurement apparatus 23, checker brick top infrared temperature measurement apparatus 25, surperficial wireless temperature measuring device 27 and thermocouple temperature measuring apparatus 28 are imported computer 26 through data acquisition unit 1, and combustion time, the highest throat temperature, checker brick head temperature and the tail flue gas temperature control hotblast stove 2 set by computer 26 commutate; In on air, cold wind enters in the stove through gas blower 29, cold wind trip valve 30, cold wind variable valve 31, cold wind parameter detecting element 22 and cold air inlet 17, the data detection signal of cold wind parameter detecting element 22 is through data acquisition unit 1, input computer 26, control data by computer 26 is controlled the aperture of cold wind variable valve 31 through data acquisition unit 1, thereby realizes the adjustment of cold flow, pressure.Hot blast enters in the stove through the hot blast variable valve 4 and the hot blast parameter detecting element 5 of hot-blast outlet 2, hot air duct 6, the data detection signal of hot blast parameter detecting element 5 is through data acquisition unit 1, input computer 26, control data by computer 26 is controlled the aperture of hot blast variable valve 4 through data acquisition unit 1, thereby realizes the adjustment of hot air flow, pressure;

As shown in Figure 2, hotblast stove is introduced into the burning phase, read gas parameters, combustion air parameter and Gas Parameters, parameter comprises temperature, pressure and flow, calculate the checker brick heat storage capacity, data such as temperature rise rate and theoretical wind-warm syndrome, revise with reality outlet wind-warm syndrome, calculate wind-warm syndrome, and with set wind-warm syndrome and compare, to exceeding the corrected Calculation wind-warm syndrome of setting the wind-warm syndrome scope, adjust combustion system, thereby adjust gas parameters, combustion air parameter and Gas Parameters are passed through furnace roof, checker brick and funnel temperature compare with the maximum of corresponding setting, when surpassing maximum, the hotblast stove commutation enters on air, reads cold wind parameter and hot blast parameter, calculates temperature drop rate and air output, determine blowing system, utilize hot blast temperature and set wind-warm syndrome relatively, adjust blowing system and adjust cold wind and the hot blast parameter, thereby realize the control that hotblast stove is stablized wind-warm syndrome; The hotblast stove calculating parameter is as shown in table 2, and the flow of detection, pressure and temperature parameter fluctuation are regulated as shown in table 3,

Table 2 hotblast stove calculating parameter:

The flow that table 3 detects, pressure and temperature parameter fluctuation are regulated

Remarks (+expression increases, and-expression is oppositely regulated)

As shown in Figure 3, the hotblast stove group is by hotblast stove A, hotblast stove B and hotblast stove C form, in the burning phase, coal gas after 88 preheatings of gas preheating device is through gas main 68, the hotblast stove A gas stop valve 38 and the hotblast stove A gas regulator 37 of hotblast stove A gas line 40 enter hotblast stove A, combustion air enters combustion air house steward 71 through combustion air gas blower 82 and combustion air primary heater unit 87, combustion air is through combustion air house steward 71, the hotblast stove A combustion air trip valve 39 and the hotblast stove A combustion air variable valve 36 of hotblast stove A combustion air pipeline 41 enter hotblast stove A, both mixed firings; Flue gas enters breadboard 52 through the hotblast stove A of hotblast stove A flue 47 flue variable valve 42, hotblast stove A flue trip valve 43; The coal gas of gas main 68 enters hotblast stove B through the hotblast stove B of hotblast stove B gas line 70 gas stop valve 63 and hotblast stove B gas regulator 62, combustion air enters hotblast stove B, both mixed firings through the hotblast stove B combustion air trip valve 64 and the hotblast stove B combustion air variable valve 61 of combustion air house steward 71, hotblast stove B combustion air pipeline 69; Flue gas enters breadboard 52 through the hotblast stove B of hotblast stove B flue 49 flue variable valve 55, hotblast stove B flue trip valve 48; The coal gas of gas main 68 enters hotblast stove C through the hotblast stove C of hotblast stove C gas line 86 gas stop valve 75 and hotblast stove C gas regulator 74, combustion air enters hotblast stove C, both mixed firings through the hotblast stove C combustion air trip valve 76 and the hotblast stove C combustion air variable valve 73 of combustion air house steward 71, hotblast stove C combustion air pipeline 81; Flue gas enters breadboard 52 through the hotblast stove C of hotblast stove C flue 51 flue variable valve 58, hotblast stove C flue trip valve 50; Three hotblast stoves gather flue gas through breadboard 52, gas preheating device 88, discharge through chimney 59; On air, cold wind enters hotblast stove A through cold wind house steward 80 through the hotblast stove A of hotblast stove A cold air duct 67 cold wind trip valve 66, hotblast stove A cold wind variable valve 65, and hot blast enters hot-blast main 46 through the hotblast stove A of hotblast stove A hot air duct 32 hot blast trip valve 34, hotblast stove A hot blast variable valve 33; Cold wind enters hotblast stove B through cold wind house steward 80 through the hotblast stove B of hotblast stove B cold air duct 79 cold wind trip valve 78, hotblast stove B cold wind variable valve 77, and hot blast enters hot-blast main 46 through the hotblast stove B of hotblast stove B hot air duct 44 hot blast trip valve 60, hotblast stove B hot blast variable valve 53; Cold wind enters hotblast stove C through cold wind house steward 80 through the hotblast stove C of hotblast stove C cold air duct 85 cold wind trip valve 84, hotblast stove C cold wind variable valve 83, and hot blast enters hot-blast main 46 through the hotblast stove C of hotblast stove C hot air duct 45 hot blast trip valve 72, hotblast stove C hot blast variable valve 56;

The valve position signal of hotblast stove A gas stop valve 38, hotblast stove A combustion air trip valve 39, hotblast stove A flue trip valve 43, hotblast stove A cold wind trip valve 66, hotblast stove A hot blast trip valve 33 imports computer 26 into by data acquisition unit 1 and carries out opening and closing control; The valve position signal of hotblast stove B gas stop valve 63, hotblast stove B combustion air trip valve 64, hotblast stove B flue trip valve 48, hotblast stove B cold wind trip valve 78, hotblast stove B hot blast trip valve 53 imports computer 26 into by data acquisition unit 1 and carries out opening and closing control; The valve position signal of hotblast stove C gas stop valve 75, hotblast stove C combustion air trip valve 76, hotblast stove C flue trip valve 50, hotblast stove C cold wind trip valve 84, hotblast stove C hot blast trip valve 56 imports computer 26 into by data acquisition unit 1 and carries out opening and closing control; Burning and air-supply are controlled to be intersection mid-shunt pattern, promptly at first in 1/2～3/4 time in hotblast stove A air-supply cycle, computer 26 is by cutting out hotblast stove B gas stop valve 63, hotblast stove B combustion air trip valve 64, hotblast stove B flue trip valve 48 and unlatching hotblast stove B cold wind trip valve 78, hotblast stove B hot blast trip valve 53 control hotblast stove B turned on air from the burning phase, form half chiasma state in parallel with hotblast stove A, then, the air-supply of computer 26 control hotblast stove C and hotblast stove B, at last, the air-supply of computer 26 control hotblast stove C and hotblast stove A, control mode and cycle control identical with the timed interval.

Claims (5)

1. A constant air temperature control system for a hot blast stove, comprising a hot blast stove (2), a gas pipeline (11), a combustion-supporting air pipeline (9), a cold wind pipeline (21), a hot blast pipeline (6), a flue (20), The data collector (1) and computer (26) are characterized in that: the control process includes fluid parameter and valve position signal detection, data acquisition, data transmission, data comparison, data correction and control adjustment process, including the following steps: ① Calculate the heat storage capacity, temperature rise rate and theoretical wind temperature of the checker bricks according to the gas parameters, combustion air parameters and flue gas parameters detected during the combustion period, and the parameters include temperature, pressure and flow; ②Comparing the actual outlet air temperature detected during the air supply period with the set air temperature, correcting the calculation of the theoretical air temperature exceeding the set range, and adjusting the gas parameters, combustion air parameters, and flue gas parameters during the combustion period; ③Compare the detected furnace top temperature, checker brick temperature and exhaust gas temperature with the set maximum values respectively, and control the reversing of the hot blast stove if the set furnace top temperature, checker brick temperature and exhaust gas temperature exceed the set maximum values; ④ According to the cold air parameters and hot air parameters detected during the air supply period, calculate the temperature drop rate, air supply volume and air supply time, and adjust the cold air flow and hot air flow according to the set air temperature; ⑤ Use the cross-semi-parallel mode to control the replacement of the hot blast stove group. 2. The constant air temperature control system for hot blast stove according to claim 1, characterized in that, the gas pipeline (11) is equipped with a gas parameter detection element (12) and a gas regulating valve (10), and the combustion-supporting air pipeline (9) is equipped with a combustion-supporting An air parameter detection element (7) and a combustion air regulating valve (8), a cold air parameter detection element (22) and a cold air regulating valve (31) are installed on the cold air duct (21), and a flue gas parameter detection element (19) is installed on the flue (20) ) and the flue regulating valve (18), the hot blast pipe (6) is equipped with a hot blast parameter detection element (5) and a hot blast regulating valve (4), and the hot blast stove (2) is equipped with a stove top infrared temperature measuring device (23) and a grid An infrared temperature measuring device (25) is installed on the top of the brick (15), a thermocouple temperature measuring device (28) is installed on the bottom of the checker brick (15), and a wireless temperature measuring device (27) is installed on the surface of the hot blast stove (2). Wherein, the gas parameter detection element (12), the combustion air parameter detection element (7), the cold air parameter detection element (22), the smoke parameter detection element (19), and the hot air parameter detection element (5) include flow, pressure and temperature Sensor; gas parameter detecting element (12), gas regulating valve (10), combustion air parameter detecting element (7), combustion air regulating valve (8), cold air parameter detecting element (22), cold air regulating valve (31), smoke Gas parameter detection element (19), flue regulating valve (18), hot air parameter detection element (5), hot air regulating valve (4), furnace top infrared temperature measuring device (23), checker brick top infrared temperature measuring device (25 ), a thermocouple temperature measuring device (28), a surface wireless temperature measuring device (27) are connected to the data collector (1) through a wired or wireless data transmission line (24), and the data collector (1) summarizes the detection signal and transmits the computer ( 26). 3. The constant air temperature control system of hot blast stove according to claim 1, characterized in that, in the combustion period of step 1., step 2. and step 3., the gas parameter detection element (12), the combustion air parameter detection element (7 ), the flow rate, temperature and pressure detected by the flue gas parameter detection element (19) and the infrared temperature measurement device (23) on the top of the furnace (23), the infrared temperature measurement device (25) on the top of the checker brick, the thermocouple temperature measurement device (28), the surface The furnace top temperature, checker brick temperature and furnace body surface temperature detected by the wireless temperature measuring device (27) are calculated by the computer (26) online software to calculate the checker brick heat storage, temperature rise rate and theoretical air temperature, and the actual outlet air temperature is used Correction is carried out by comparing the calculated wind temperature with the set wind temperature, and adjusting the opening degree of the gas regulating valve (10) and the combustion air regulating valve (8 ) opening, gas temperature and combustion air preheating temperature to realize the adjustment of gas flow, gas temperature and combustion air flow, and combustion air temperature; when the detected flow, pressure and temperature parameters change, apply the principle of constant air temperature to adjust each Detection parameters; when the combustion time, the maximum temperature of the furnace top, the temperature of the top of the checker brick, and the temperature of the flue gas at the tail exceed the set value, the hot blast stove will be replaced; The hot blast stove adopts full combustion of blast furnace gas, which specifically includes the following steps: (1) Gas flow, gas pressure, gas temperature, combustion air flow, combustion air pressure, combustion air temperature, flue gas flow, tail flue gas temperature parameter detection, (2) Burning time, maximum furnace top temperature, checker brick top temperature, exhaust gas temperature setting, ①The burning time is 40~110min; ②The maximum temperature of furnace top is 1400～1450℃; ③The temperature at the top of the checker brick is 1250-1350°C; ④The tail gas temperature is 200～400℃; (3) Calculation of checker brick heat storage, temperature rise rate and theoretical wind temperature parameters, ① Calculation of heat storage capacity of checker bricks, ${\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}}<span\; class="notranslate">\; =</span>{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}{\mathrm{<span\; class="notranslate">\; c</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}}\mathrm{<span\; class="notranslate">\; d</span>}{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}}\mathrm{<span\; class="notranslate">\; d</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; d\&tau;</span>}$ In the formula: Q _z - checker brick heat storage, kJ, C _z - checker brick heat capacity, kJ/(kg.℃); M _z - checker brick mass, kg; T _z - checker brick temperature, ℃; τ - time , s; ②Calculation of checker brick temperature rise rate, $\mathrm{<span\; class="notranslate">\; wxya</span>}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; dT</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}}}{\mathrm{<span\; class="notranslate">\; d\&tau;</span>}}$ In the formula: S-temperature rise rate, ℃/s; ③Theoretical wind temperature calculation, ${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; dw</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; k</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}}{{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}}$ In the formula: Q _dw - low calorific value of gas, kJ/m ³ ; C _g - heat capacity of gas, kJ/(m ³ .℃); V _g - volume flow rate of blast furnace gas, m ³ /s; T _g - gas Preheating temperature, ℃; C _a - heat capacity of combustion air, kJ/(m ³ .℃); V _a - volume of combustion air, m ³ ; T _a - preheating temperature of combustion air, ℃; C _f - heat capacity of hot air , kJ/(m ³ .℃); V _f - hot air volume flow rate, m ³ /s; T _f - theoretical air temperature, ℃; k - air-fuel ratio, 0.6～0.7; Q _s - heat loss of hot air stove, kJ; (4) Estimating the combustion time according to the temperature rise rate of checker bricks or adjusting the temperature rise rate of checker bricks according to the furnace replacement time, and then adjusting the flow rate of blast furnace gas and combustion air, (5) Correct the calculation of outlet air temperature, T _fs = ξT _f T _fs - actual wind temperature, ℃; ξ - correction factor; (6) Correct the gas preheating temperature and combustion air preheating temperature, (7) The gas parameters and combustion air parameter fluctuations in the detection process are adjusted inversely, and the gas calorific value fluctuations are positively adjusted to the air-fuel ratio. ① Gas pressure, gas flow, and gas temperature fluctuate by more than 2% to 5%, and the reverse adjustment is 2% to 5%; ② Combustion air pressure, combustion air flow, combustion air temperature fluctuations exceed 2% to 5%, reverse adjustment 2% to 5%, ③The calorific value of gas fluctuates by more than 2% to 5%, and the air-fuel ratio is adjusted positively by 2% to 5%. (8) The combustion time and set temperature are out of range, the combustion period is over, and the hot blast stove is replaced. 4. The constant air temperature control system for hot blast stoves according to claim 1, characterized in that, according to step ④, during the air supply period, the flow rate detected by the cold air parameter detection element (22) and the hot air parameter detection element (5) , temperature, pressure and furnace top temperature detected by furnace top infrared temperature measuring device (23), checker brick top infrared temperature measuring device (25), thermocouple temperature measuring device (28), surface wireless temperature measuring device (27), Checker brick temperature and furnace body surface temperature, using checker brick heat storage and air temperature data, calculate checker brick temperature drop rate and air supply volume, and adjust the opening degree of cold air regulating valve (31) or hot air regulating valve (4) through computer (26) Opening, to complete the adjustment of the cold air flow and hot air flow, so as to achieve the stable control of the hot air outlet temperature; when the air supply time and the outlet temperature of the hot blast stove are lower than the set air temperature control accuracy range, the hot blast stove will be replaced; The air supply control process specifically includes the following steps: (1) Detection of cold air parameters, hot air parameters, checker brick top temperature and bottom temperature, and furnace surface temperature; (2) The air temperature control accuracy range is ±4°C of the set air temperature, (3) Estimate the air supply time by using the heat storage capacity of checker bricks and the temperature drop rate of checker bricks, (4) Calculation and control of air supply volume, ${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; Q</span>}}_{\mathrm{<span\; class="notranslate">\; z</span>}}}{{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; fs</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; fs</span>}}}$ In the formula: Q _z - heat storage of checker bricks, kJ; T _fs - actual air temperature, ℃; C _fs - heat capacity of hot air, kJ/(m ³ .℃); When the air temperature drops by 2°C, turn off the hot air regulating valve (4) and the opening degree of the cold air regulating valve (31) by 1%; (5) The air supply time and set air temperature parameters are out of range, the air supply period is over, and the hot blast stove is replaced. 5. The constant blast temperature control system of hot blast stove according to claim 1, characterized in that, according to step 5., the hot blast stove group is made up of hot blast stove A, hot blast stove B and hot blast stove C, and the gas main pipe (68) is connected to the hot blast stove A gas pipeline (40), hot blast stove B gas pipeline (70) and hot blast stove C gas pipeline (86) link to each other, combustion-supporting air main pipe (71) and hot blast stove A combustion-supporting air pipeline (41), hot blast stove B combustion-supporting air pipeline ( 69) is connected with the hot blast stove C combustion air duct (81), the flue main pipe (52) is connected with the hot blast stove A flue (47), the hot blast stove B flue (49) and the hot blast stove C flue (51), and the cold air The main pipe (80) is connected with the hot blast stove A cold air duct (67), the hot blast stove B cold air duct (79) and the hot blast stove C cold air duct (85), and the hot blast main pipe (46) is connected with the hot blast stove A hot blast duct (32), the hot blast stove B hot blast pipe (44) links to each other with hot blast stove C hot blast pipe (45); The valve position signals of furnace A cold air shut-off valve (66) and hot blast stove A hot blast shut-off valve (33) are transmitted to computer (26) through data collector (1) for opening and closing control; hot blast stove B gas shut-off valve (63) , hot blast stove B combustion air cut-off valve (64), hot blast stove B flue cut-off valve (48), hot blast stove B cold air cut-off valve (78), hot blast stove B hot air cut-off valve (53) valve position signals through the data collector (1) import into computer (26) and carry out opening and closing control; Hot blast stove C gas cut-off valve (75), hot blast stove C combustion-supporting air cut-off valve (76), hot blast stove C flue shut-off valve (50), hot blast stove C The valve position signals of the cold wind shut-off valve (84) and the hot blast stove C hot blast shut-off valve (56) are transmitted to the computer (26) through the data collector (1) for opening and closing control; combustion and air supply adopt a cross-semi-parallel mode, and the computer Furnace replacement is cross-controlled at the same time interval, and the ratio of the time interval to the air supply cycle is 1/2 to 3/4.

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