SU1738762A1 - Method of control of heating conditions of regenerative glass-making furnace - Google Patents

Abstract

Use: glass industry. SUMMARY OF THE INVENTION: The method consists in choosing three characteristic points in time for measuring the temperatures in the furnace, comparing these temperatures with the given values for these points in time, and using the data obtained produces two corrective actions on the fuel consumption for the last two burners in the furnace. 2 Il.

Description

The invention relates to the glass industry, in particular to the automatic regulation of the glassmaking process.

The aim of the invention is to improve the quality of control.

The essence of the method is as follows.

The stabilization of the gas medium temperature is ensured by the fact that the gas flow correction is carried out at certain points in time selected from the conditions of the completion of transient processes and taking into account the transport delay in the control object through the gas flow channel - the gas medium temperature.

FIG. Figure 1 shows graphs of changes in the temperature of the gaseous medium and the flow rate of gas supplied to the last burner of the furnace. From the graph T f (g), it follows that in period I, when gas is supplied to the left and its

the flow rate is constant Q const, the temperature of the gas medium rises from TA to Tv. At time A, the furnace is purged and the gas supply is changed from left to right, the temperature changes (decreases) from Tv to Tc, then T1 is heated for an interval T1 and the temperature becomes equal to Td. This value is remembered, and the temperature in the furnace for the next period of time rises to TE, at this point the first correction gas flow rate Aqi is calculated based on the measured values from the difference between ATi TE - TDi

AT2 Tzad - TE. This value of the gas flow / Oto + Aqi is kept for ts, Df is calculated based on the measured values of temperature TE and T from the difference ATz Tr - TB and A T4 Tzad2 - Tr and withstand the gas flow Oto + Af for time G4 + Ti + T2 . Next, the calculation process

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LDd is repeated, but already with new measured values Td1, TЈ1, Tr1 after changing the direction of the flame.

The value of the time interval TI is chosen equal to 0.5 to 0.8 of the time of purging. In this case, the value of the gas medium temperature in the trowel furnace is no longer affected by the consequences of the purge and it depends on the glass melt temperature, gas consumption, and lining temperature.

The value of the time interval tg is chosen equal to (2-3) l. At the same time, the value of the temperature of the gas medium in the stud room of the furnace TB is already influenced mainly by the change in the gas flow rate carried out to the previous flame transfer. The predetermined temperature of the gas medium at the moment of time bj + tg from the beginning of the transfer of the flame of the TELDB is determined by calculation when calculating the heat and material balance of the furnace and is refined in experimental studies on a specific furnace.

The value of the time interval gz is chosen equal to 2 TI. In this case, the gas temperature in the furnace tube Tp is already affected only by changes in the gas flow rate Aqi, and the set value Rsad at the time from the start of the transfer (t + TI + t3) is also determined by calculation when designing the furnace and is experimentally specified in moment of testing.

The calculation of the first adjustment of the fuel consumption Aqi is carried out for the period between flame transfers using the formula

DD1 K1 (TE-TD | + K2 (Tzad-TE), (1)

where Ki and Ka are the gain factors, which are chosen based on the static characteristics of the control object.

The calculation of the second fuel consumption adjustment is made according to the formula

&} 2 K1 (Tr-TE) + K2 (Tzad-Tr) (2)

This method is carried out using the device shown in FIG. 2, and contains part of a glass melting regenerative furnace 1, into which natural gas passes through burners 2 and 3, switching valves 4 and 5, gas flow sensor 6, controller 7, gas flow setting device 8, actuator 9, regulator 10, heat chamber 11, relay elements 12–14, memory blocks 15 and 16, - accumulators-amplifiers 17-20, temperature adjusters 21 and 22, adders 23 and 24, switch 25, memory block 26, and flame transfer control unit 27.

The device works as follows.

The signal from the heat chamber 11, fixing the temperature of the gas environment, equal to

for example, 1321 ° C, varies, goes to the inputs of relay elements 12-14, which are triggered after certain predetermined time periods, for example, t 5 min, ri + T2 12 min, g + T2 + TZ 26 min, after

the arrival at their additional inputs of the start signal of flame transfer from block 27. For example, 5 minutes after the start of flame transfer, a relay element passes through relay element 12 to memory block 15

signal from the heat chamber 11 (1321.5 ° C). 12 minutes after the start of flame transfer, the relay element 13 passes a pulse signal from the heat chamber 11 (1322 ° C), from which the signal from the memory block 15 (1321 ° C) is subtracted, and is amplified by the difference depending on the object's gain factor 8 times. These operations are performed in the adder-amplifier 17, the output of which receives a signal to

the first input of the adder 23. Simultaneously, in the adder-amplifier 18, the signals are subtracted, the signal from the output of the relay element 13 (1322 ° C) is subtracted from the setpoint temperature signal (1323 ° C) and, for example, this difference is amplified by the second input of the adder 23, from the output of which the sum signal equal to 8 + 5 13 m / h goes to switch 25, which in the period from 12 to

12 min - 1 sec passes the signal from the output of the adder 23 to the memory block 26. From the last signal, 13m3 / h is fed to the auxiliary input of the regulator 7. At the same time, the regulator 7 generates a +24 signal at

switching on the actuator 9, which turns the regulator 10 towards its opening until the signal from the sensor 6 increases by 13 m3 / h relative to the set point 8, for example 390 m3 / h, and the gas flow to the burner is 403 m3 / h. This flow rate is maintained for up to 26 minutes after the start of flame transfer. In addition, in memory block 16, the signal of the heat chamber 11 is memorized by 12

minute (1322 ° C).

At 26 minutes, the relay element 14 is triggered, through which the pulse signal from the heat chamber (1323 ° C) passes, from which the signal from the memory block 16 (1322 ° C) is subtracted, this difference is amplified 8 times. These operations of subtraction and amplification are performed in adder-amplifier 19, from the output of which the signal goes to the first input of adder 24.

At the same time, in the adder-amplifier 20, the signals are subtracted - the signal from the setpoint 22 (1325 ° C) is subtracted from the output of the relay element 14 (1323 ° C), this difference is amplified 5 times and fed to the second input of the adder 24, from which the sum signal equal to 1-8 + 2-5 18 m3 / h is fed to the switching channel 5, which in the period from 26 to 26 min 1 s passes the signal from the output of the adder 24 to the block 26 of memory 26, from which the signal q 18 m3 / h is fed to the auxiliary input of the regulator 7. At the same time, the latter produces a +24 signal for switching on an actuator 9 that turns the regulator towards its opening until the signal from sensor 6 increases by 18-13 5 m / h and the gas flow rate to the burner is 408 m3 / h. This gas flow is maintained for up to 12 minutes after the start of the next flame transfer. The subsequent regulation of the gas flow is carried out in a similar manner.

This method allows to stabilize the temperature of the gas medium in the stud part of the furnace, and consequently, stabilize the temperature in the center of the production channels, thereby improving the quality of the glass mass, reduce scrap by 0.5% and reduce fuel consumption by 1.5% .

Claims (1)

Invention Formula The method of controlling the thermal regime of a glass melting regenerative furnace, including measuring the temperature in the stove part of the furnace, stabilizing and correcting the fuel consumption in the burners, characterized in that, in order to improve the quality of control, the temperature in the stud part of the furnace is measured at three predetermined points in time between the transfer of the flame temperature differences between the second and first, third and second measurements and deviations of the temperatures of the second and third measurements from those specified for these times are carried out in the period between the second and third measurements a first fuel flow adjustment proportional to the sum of the temperature differences of the second and first measurements and the deviation of the temperature of the second measurement from the given one, the second adjustment of the fuel consumption is carried out in the period between the third temperature measurements in this mode and after the transfer of the flame is proportional to the sum of the temperature difference between the third and second measurements and the deviation of the third measurement temperature from the specified one. Go cseeci i  Ghz s-praba Qr 7Т Ш tf "" y yc H with pin Bz baby FIG. 2