JP2797943B2 - Mixed gas calorie control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calorie control device for a mixed gas, and more particularly to a calorie control device for converting a high calorie gas into an appropriate low calorie diluent gas in a fuel facility such as steel or electric power.

[0002]

2. Description of the Related Art Controlling the calories of a mixed gas of a plurality of different gases is not limited to a dilution gas (mixed gas of fuel gas and air). Furnaces and boilers) are important issues in terms of energy saving and safety. For example, when a heating furnace is taken as an example, the amount of combustion greatly varies depending on the lower process load of the heating furnace. This amount of variation is commonly known as turndown, and when the calorie of the mixed gas fluctuates due to this turndown, the variation enriches the combustion air, which increases fuel consumption more than necessary. Energy consumption increases. Conversely, if the combustion air is not enriched, air will be insufficiently burned, and unburned unburned components will be discharged from the chimney etc.If the proportion of the unburned components increases, backfire or explosion may occur. There is also. A calorie control method for a mixed gas composed of a low calorie gas and a high calorie gas is disclosed in JP-A-61-670.
This method is disclosed in Japanese Patent Application Publication No. 2 (1995) -207, which detects a load variation from the discharge pressure of the mixed gas, controls the flow rate of the low-calorie gas according to the variation, and changes the flow according to the calorie variation range of the mixed gas. The gain is used to control the flow rate of the high calorie gas, and to perform feedback control so that the calorie of the mixed gas becomes a predetermined value.

[0003]

However, this conventional control method can be used only when the turndown ratio is relatively small. That is, an orifice-type differential pressure flow meter is usually used for measuring the gas flow rate. However, this flow meter cannot measure the flow rate accurately because the measurement error is large for 10% or less of the measurement range. Therefore, when the turndown is required to be 10% or less of the measurement range, there is a problem that the mixing accuracy in a low flow rate region cannot be obtained. Therefore, an object of the present invention is to improve the calorie control accuracy of a mixed gas by enabling the gas mixing accuracy to be increased even in a low flow rate region in a mixed gas calorie control device.

[0004]

In order to achieve the above object, a mixed gas calorie control apparatus according to the present invention comprises:
A large-capacity first pipe and a small-capacity second pipe for distributing and supplying the second gas; a large-capacity third pipe for distributing and supplying the second gas; A fourth pipe,
First and second control valves interposed in the first pipe and the second pipe, respectively, for controlling the flow rate of the first gas;
Third and fourth control valves interposed in the third pipe and the fourth pipe, respectively, for controlling the flow rate of the second gas;
The first and second gases supplied from the first, second, third and fourth pipes are mixed via the first, second, third and fourth control valves and supplied to the output pipe. Means for measuring the flow rate of the first gas flowing through the first and second pipes, and the second and third flow meters for measuring the flow rate of the first gas flowing through the third and fourth pipes. Third and fourth flow meters for measuring the flow rate, a fifth flow meter for measuring the flow rate of the mixed gas flowing through the output pipe, and first, second, third, fourth and fifth flow meters. The first, second, and third according to the measurement value of the flow meter, the flow rate of the mixed gas to be supplied from the output pipe, and the first and second ratios of the first and second gases to the mixed gas. And control means for controlling the degree of opening of the fourth control valve, wherein when the measured value of the fifth flow meter is less than or equal to a predetermined value, Control valve is closed, and the measured values of the second and fourth flow meters are obtained by multiplying the flow rate of the mixed gas to be supplied from the output pipe by the first and second ratios, and The second and fourth control valves are controlled so that the measured value of the fifth flow meter is equal to or greater than a predetermined value.
Controlling the second and fourth control valves to be in a closed state;
And controlling the first and third control valves such that the measured value of the third flow meter becomes a flow value obtained by multiplying the flow rate of the mixed gas to be supplied from the output pipe by the first and second ratios. And control means configured to perform the control.

In another apparatus for controlling the calorie of a mixed gas of the present invention, a large-capacity first pipe and a small-capacity second pipe for distributing and supplying a first gas are provided.
A large-capacity third pipe and a small-capacity fourth pipe for distributing and supplying the first gas, and a first pipe and a second pipe are interposed in the first pipe and the second pipe, respectively, to control the flow rate of the first gas. First and second control valves, and third and fourth control valves for controlling the flow rate of the second gas, which are interposed in the third pipe and the fourth pipe, respectively. Mixer for mixing first and second gases supplied from first, second, third and fourth pipes via second, third and fourth control valves and supplying the mixed gas to output pipes Means and a first gas source.
And a first flow meter for measuring the original flow rate of the first gas supplied to both the second pipe and the second flow rate for measuring the flow rate of the first gas supplied to the second pipe. And a third flow meter for measuring the original flow rate of the second gas supplied from the second gas supply source to both the third and fourth pipes.
And a fourth flow meter for measuring the flow rate of the second gas supplied to the fourth pipe, and the first, second, and third flow meters.
And the measurement value of the fourth flow meter, the flow rate of the first gas in the mixed gas to be supplied from the output pipe, and the mixing ratio of the first gas and the second gas in the mixed gas,
Control means for controlling the degree of opening of the first, second, third and fourth control valves, wherein when the measured value of the first flow meter is not more than a predetermined value, the first control valve is Controlling the second control valve in a closed state and controlling the second control valve so that the measured value of the second flow meter becomes the flow rate of the first gas in the mixed gas to be supplied from the output pipe; If the measured value of the flow meter is equal to or more than the predetermined value, the second control valve is controlled so that the measured value of the second flow meter holds the predetermined value, and the first flow rate flowing through the first pipe is controlled.
The third control valve controls the first control valve so that the first gas becomes the difference between the flow rate of the first gas in the mixed gas to be supplied from the output pipe and the predetermined value. Control means configured to control the third and fourth control valves so that the measured value of the meter becomes a flow rate obtained by multiplying the measured value of the first and second flow meters by the mixing ratio. It is characterized by having.

That is, according to the present invention, each gas to be mixed is guided to a mixer means through a large-capacity pipe and a small-capacity pipe, and a flow rate of a mixed gas supplied from an output pipe or a predetermined gas in the mixed gas is mixed. The flow rate is monitored, and when the flow rate is in a low flow rate region, a plurality of gases to be mixed are supplied to the mixer means only through the small-capacity pipe, and the measurement for the large-capacity pipe is performed. By not using the measured value of the flow meter with a wide range substantially in the low flow rate area, the measurement accuracy in the low flow rate area can be improved, and thereby the gas mixing precision can be improved. I have.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG 1 describes a calorie control apparatus for a gas mixture based on 2 distributive mixing method of an embodiment of the present invention, in FIG. 1, 1 _A supplies a gas A, such as LPG gas a gas supply source for, the gas a is supplied to the large pipe 3 _a through the safety shut-off valve 2 _a, further part is distributed to the small-capacity pipe 3a. For large capacity piping 3 _A ,
Measurements and wide flow meter 4 _A and the control valve 5 _A is interposed a range Likewise, small-capacity pipe 3 _a, the narrow flow meter 4 _a and the control valve 5 _a measurement ranges is interposed . Control valve 5 _A, 5 _a is the degree of opening of the flow controllers (FIC) valve by 6 _A, 6 _a are controlled respectively. 1 _B is a blower for supplying the air B mixed with the gas A, and the air from the blower is distributed to the large capacity pipe 3 _B and the small capacity pipe 3 _b . Then, as in the case of gas A, each pipe 3 _B
And 3 _b is provided with wide flow meter 4 _B measurement ranges, the control valve 5 _B and a flow regulating meter 6 _B, and a small flowmeter 4 _b of the measuring range, the control valve 5 _b and a flow regulating meter 6 _b.

Further, a large capacity mixer 7 _AB for mixing the gas A and the air B in the large capacity pipes 3 _A and 3 _B and the small capacity pipes 3 _a and 3 _b for each of the large capacity pipe and the small capacity pipe. , A small-volume mixer 7 _ab , the diluent gas mixed in each mixer is collected in one output pipe, and is passed through a flow meter 8 and a pressure gauge 9 for detecting a load change by a pressure change. It is supplied to a burner (not shown) such as a heating furnace. The output of the pressure gauge 9 is supplied to a pressure regulator 10, which generates an output to regulate the pressure of the dilution gas flowing through the output pipe. The output from the pressure controller 10 is supplied to a flow controller 11 for adjusting the flow rate of the diluent gas supplied from the output pipe as a result.
At 1, pressure / flow rate conversion is performed, and the flow rate of the dilution gas to be supplied from the output pipe is supplied to the ratio meters 12 _Aa and 12 _Bb . Further, the flow controller 11 monitors the flow rate of the flow meter 8 and outputs a signal indicating whether or not the measured value is equal to or less than a predetermined value to the ratio meter 12.
_Aa and 12 _Bb . The flow controllers 6 _A and 6 _a for controlling the flow rate of the gas A are the output of the ratio meter 12 _Aa and the flow meter 4.
_A, 4 controls the opening degree of the control valve 5 _A, 5 _a in accordance with the measured values of _a, also the flow rate adjusting meter 6 _B, 6 _b for regulating the flow rate of air B, ratiometer 12 _Bb output and controlling the opening degree of the control valve 5 _B, 5 _b in accordance with the measured value of the flow meter 4 _B, 4 _b.

The operation of the embodiment constructed as described above will be described in detail below with reference to the graphs of FIGS. The maximum flow rate of the small-capacity pipe 3 _a and the air B small-capacity pipe 3 _b of the gas A, the maximum flow rate Q _MAXB the maximum flow rate Q _MAXA and air B of large pipe 3 _A gas A, i.e. the flow meter 4 _A And 15 of measurement range (full scale) of 4 _B
%, Respectively.
The dilution gas flow rate Q _AB (that is, the measurement value of the flow meter 8) supplied from the mixer 7 _AB to the burner via the output pipe, as shown schematically in FIG. It shall be controlled so as to vary the output of the adjusting meter 10, and more ratiometer 12 _Aa, 12 _Bb, the ratio R _a gas a of the dilution gas relative to the dilution gas to be output from the output pipe, the air B shall ratio R _B is set in advance. Thus, each gas A and the air B in the diluted gas Q _A, when the Q _B, is expressed by _{Q A = R A Q AB Q} B = R B Q AB.

Gas A and air B are supplied from a gas supply source 1 _A and a blower 1 _{B. A} flow controller 11 monitors a measured value Q _AB of the flow meter 8, and the measured value is a full range of the flow meter 8. If less than the predetermined value Q is for example 15%, the gas a and the air B only through the small-capacity pipe 3 _a, 3 _b is controlled to be supplied. That is, the flow controller 11 supplies a signal indicating whether or not the measured value of the flow meter 8 is equal to or more than the predetermined value Q together with the flow rate Q _{AB of the} dilution gas to be supplied to the ratio meters 12 _Aa and 12 _Bb . Each of these ratios meter performs an operation of _{Q AB × R A Q AB ×} R B, and if the measured value of the flowmeter 8 is supplied with a signal indicating that it is equal to or less than the predetermined value Q is obtained It was supplied a calculation result with respect to flow rate control meter 6 _a, 6 _b provided on the small-capacity pipe. Thus the flow adjusting meter 6 _a, 6 _b, the measurement value of the flow meter _{4 a, 4 b Q a1,} Q b1 is _{Q a1 = Q A = R A} Q AB Q b1 = Q B = R B Q AB as such, it controls the opening of the control valve 5 _a, 5 _b. At this time, the control valve 5 _A, 5 _B large capacity pipe 3 _A, 3 _B is controlled to remain closed. Therefore, the supply amount Q of the dilution gas
_In the period (0 to t ₁ ) in which _AB is equal to or less than Q, that is, the flow rate Q _A of gas A in the dilution gas is equal to or less than R _A Q, FIG.
As shown in (B) and (C), the gas A is supplied only through the small-capacity pipe 3 _a.

Then, the flow rate Q _a1 of the small-capacity pipes 3 _a and 3 _b ,
Q _b1 increases, and at time t ₁ , these flow rates Q _a1 and Q _b1 become R
_A Q, and reaches the R _B Q, since the measured value Q _AB of flowmeter 8 provided on the output pipe becomes _{Q AB = R A Q + R} B Q = Q ∵ R A + R B = 1, the flow adjusting meter 11 Transmits the flow rate Q _{AB of the} dilution gas to be supplied from the output pipe to only the flow controllers 6 _A and 6 _{B of} the large-capacity pipe via the ratio meters 12 _Aa and 12 _{Bb. a,} 4 as measured values Q _A1, Q _B1 of _B is _{Q A1 = Q a = R a} Q AB Q B1 = Q B = R B Q AB, controls the opening of the control valve 5 _a, 5 _B I do. It along with the control valve 5 _a, 5 _b is controlled closed, therefore the measured values Q _AB is Q or more periods of the flow meter 8 (t ₁ ~t _2), gas A and the air B is large pipe 3 _A and only through 3 _B supplied. At the time t ₂ and later, the flow meter 8
Is smaller than or equal to Q, and the gas A and the air B are supplied again only through the small-capacity pipes 3 _a and 3 _b by the action of the flow controller 11. The gas A and the air B whose flow rates are controlled in this manner are mixed by the mixers 7 _AB and 7 _ab for each of the large-capacity pipe and the small-capacity pipe, and are supplied to a burner or the like via an output pipe.

[0012] As described above, in the embodiment shown in FIG. 1, the gas A and the air B is dilution gas in the following low flow region given flow rate Q through the only small-capacity pipe 3 _a, 3 _b It is supplied, in a predetermined flow rate Q over a region large pipe 3 _a, 3 _B
Supplied via only. The flow meter 8 having a wide measurement range is used only for monitoring whether or not the flow rate of the dilution gas is equal to or less than the predetermined value Q, thereby switching between the large-capacity pipe and the small-capacity pipe, and since the measurement range in the low flow region is performing flow control using only a low flow meter 4 _a, 4 _b, the flow control of the low flow rate region can be performed with high accuracy.

FIG. 3 shows a calorie control apparatus for a mixed gas according to another embodiment of the present invention. In FIG. 3, components having the same or almost the same functions as those of the embodiment shown in FIG. The same reference numbers are given. Figure In third embodiment, the flow meter 4 _A, 4 _B in FIG. 1, the flow meter 4 _A for measuring the original flow rate of the previous gas distributing gas to a small volume piping from the large capacity pipe ', 4 _B' And the flow meter 8 in FIG. 1 is deleted. _A mixing ratio meter (R) 13 _AB is provided between the flow meter 4 _A ′ and the flow controller 6 _B, and a mixing ratio meter 13 _ab is provided between the flow meter 4 _a and the flow controller 6 _b . . The flow controllers 6 _A , 6 _B , 6 _a , 6 _b are intelligent controllers, each having a built-in microprocessor and having four arithmetic operations and a sequence control function. Then, the flow adjusting meter 6 _A is a flow meter 4 _A 'controls the control valve 5 _A in accordance with the output of the measured value and the pressure adjusting meter 10 and 4 _a, the flow rate adjusting meter 6 _B, the flow meter 4 _B' and controls the control valve 5 _B in accordance with the output of 4 _b measurements and mixing ratio meter 13 _AB of flow rate adjusting meter 6 _a is controlled in accordance with the output of the measured value and the pressure adjusting meter 10 flow meter 4 _a to control the valve 5 _a, the flow adjusting meter 6 _b is configured to control the control valve 5 _b in accordance with the output of the measured value and the mixing ratio meter 13 _ab flowmeter 4 _b.

The mixing ratio R of the air B to the gas A is set in both the mixing ratio meters 13 _AB and 13 _ab , and the mixing ratio meter 13 _AB calculates the mixing ratio of the gas A from the flow meter 4 _A ′. by multiplying the R and supplies the large flow rate adjusting meter 6 _B air B, mixing ratio meter 13 _ab is small for by multiplying the mixture ratio R in the measurement value of the gas a air B from the flow meter 4 _a and it is configured to supply the flow rate adjusting meter 6 _b of the capacitor. Further, in this embodiment, the gas mixed by the small-volume mixer 7 _ab is led to the large-capacity pipe 3 _A for gas A, and in the large-capacity mixer 7 _AB , a small amount of air from the large-capacity pipe 3 _{A is} reduced. is configured to entrained gas and air from the large pipe 3 _B are mixed. Incidentally, 14 is Chakki check valve is interposed in the mass pipe 3 _A immediately before the mixer 7 _AB, also 15 _B, 16 _B, 17 _B controls the rotation speed of the blower 1 _B Blower A pressure gauge, a pressure controller, and a blower rotation speed control device (BRC) for controlling the air pressure from the engine to a predetermined value.

The operation of the embodiment constructed as described above will be described below with reference to the graphs of FIGS.
Note also in this embodiment, the maximum flow rate of the small-capacity pipe 3 _b of small-capacity pipe 3 _a and the air B in the gas A, the maximum flow rate Q of the maximum flow rate Q _MAXA and air B of large pipe 3 _A gas A
_MAXB, i.e. as a, for example 15% flow meter 4 _A 'and 4 _B' measurement range (full scale), is assumed to be set respectively. Also, as the flow rate Q _A of the gas A in the diluted gas through the output pipe from the mixer 7 _AB is supplied to the burner (not shown) is schematically illustrated for explanation in FIG. 4 (A), It changes according to the output from the pressure controller 10, and further, the mixing ratio R of the air to the gas A of the diluting gas from the output pipe is measured by the mixing ratio meter 13.
_AB , 13 _ab . Gas A and air are supplied from gas supply source 1 _A and blower 1 _B ,
In the flow meters _4A 'and _4B ', the flow rate of gas A _QA1 and air B
Of it flow Q _B1 is measured, it will be described first flow control of the gas A.

[0016] The flow rate adjusting meter 6 _A, the measured value of Q of the flow meter 4 _A '
Monitors _A0, measured value is, for a given value Q ₁ below corresponding to 15% of the full range of the flow meter 4 _A ', large capacity pipe 3 _A
Controls to hold the remains closed control valve 5 _A of. On the other hand, the flow rate adjusting meter 6 _a of the small-capacity pipe 3 _a, the flow rate meter 4
As the measured value of _a is a value in accordance with the set value shown in FIG. 4 (A), and controls the opening degree of the control valve 5 _a, in the gas supply amount is small predetermined period (0 to t ₁₎ , gas a as shown in FIG. 4 (B) and (C) is supplied only through the small-capacity pipe 3 _a. Therefore, small-capacity pipe 3 _a flow rate Q
_a1 is represented by Q _a1 = Q _A0 . Subsequent control, the flow rate Q _a1 small capacity pipe 3 _a is increased, when the flow rate Q _a1 at time t ₁ becomes a predetermined value Q ₁ is 15% of the maximum flow rate Q _MAXA gas A, the flow meter 4 _A The measured value Q _{A0 of} ′ becomes the predetermined value Q ₁ . Therefore, at time t
In _one later, is held in the opening (fully opened state) of the control valve 5 _a is time t _1, a continuous flow of maximum flow Q ₁ which can flow in the small-capacity pipe 3 _a as shown in FIG. 4 (C), At the same time, the signal is supplied to control the control valve 5 _a at a predetermined flow rate from the flow rate control meter 6 _a, gas a flow rate Q _A1 also through the large pipe 3 _a is shown in FIG. 4 (B) whereby As supplied.

The measured value Q _A0 of the flow meter 4 _A ′ is represented by Q _A0 = Q _A1 + Q _a1 , and thus Q _A1 = Q _A0 −Q _a1 . Accordingly, the flow rate adjusting meter 6 _A, the measured value Q
The difference between _A0 and the measured value Q _a1 is calculated, and the difference is calculated as Q _A −Q
_a1 (setting value - flow rate value of the small capacity pipe) in which it controls the control valve 5 _A to be equal. That is, in the _{Q A1 = Q A0 -Q a1 =} Q A -Q a1 time t ₂ later, the flow rate set value Q _A gas A falls below a predetermined value Q, the control action of the flow regulating meter 6 _A, again gas a of the control valve 5 _a closure through a large pipe 3 _a
Supply is stopped. The small-capacity pipe 3 _a of the control valve 5 _a
There is controlled by a flow regulating meter 6 _a, the flow rate Q _a1 is controlled so as to decrease according to the set value Q _A.

Next, control of the flow rate of air will be described.
Measured values Q _A0 and Q of flow meters 4 _A ′ and 4 _a for gas A
_a1 is supplied to the mixing ratio meters 13 _AB and 13 _ab , respectively, and the measured value is multiplied by the mixing ratio R (air flow rate Q _B / gas A flow rate Q _A ). R × Q _A0 R × Q _a1 These values are supplied to the flow controllers 6 _B and 6 _b for air, respectively. In the flow controller 6 _b , the measured value Q _b1 from the flow meter 4 _b and the mixing ratio meter are mixed. The difference R × Q _a1 −Q _b1 from the output R × Q _a1 from 13 _ab is calculated and this difference is zero (ie, R × Q _a1 =
As the Q _b1), the opening degree of the control valve 5 _b is controlled.
On the other hand, in the flow rate adjusting meter 6 _B, the difference between the measured value Q _b1 from the measured value Q _B0 and flowmeter 4 _b from the flow meter 4 _B 'is calculated, the difference is, from the mixing ratio meter 13 _AB output R × Q _A0 and to be equal to the difference between the measured value Q _b1 from the flow meter 4 _b, to control the control valve 5 _B. That is, the flow rate Q _B1 of the air flowing through the large pipe 3 _B is represented by _{Q B1 = Q B0 -Q b1 =} R × Q A0 -Q b1.

By the way, in the period up to the time point t _{1 in} FIG. 4, the gas A is supplied only through the small-capacity pipe 3 _a , so that the control is performed so as to be equal to the output R × Q _a1 of the mixing ratio meter 13 _ab. The measured value Q _b1 from the flow meter 4 _b is equal to the output R × Q _A0 from the mixing ratio meter 13 _AB . _{Thus, Q B1 = R × Q A0} -Q b1 = R × Q A0 - (R × Q A0) = 0 Therefore, the flow regulating meter 6 _B for a period of up to time t _1, and the period from time point t ₂ is , held in remains closed control valve 5 _B, the other period (t ₁ ~t _2), like air flow Q _B1 flows large pipe 3 _B, opening of the control valve 5 _B Control the degree. Thus the gas A and the air flow rate is controlled, in the mixer 7 _ab of first small volume, the gas A and the air B in the small-capacity pipe 3 _a, 3 _b are mixed, for the mixed gas is a gas A It is introduced into the large-capacity pipe 3 _a of. Then in a mixer 7 _AB of large capacity, and the gas A air is mixed a small amount from the large-capacity pipe 3 _A and the air from the large pipe 3 _B are mixed and supplied to the burner of the heating furnace.

In controlling the calorie of the dilution gas from the output pipe, it may be necessary to keep the ratio between the gas A and the air B constant. In this case, the ratio meter 12 _Aa ,
Ratio R _A , R _B set to 12 _Bb , or mixing ratio meter 1
The mixing ratio R set to 3 _AB and 13 _ab is always constant. Further, the present invention is also applicable to a case where the calorie is appropriately changed and controlled. In this case, the ratio R _A , R _B or the mixing ratio R is set to be changed according to the changed calorie and the flow rate of the gas A. Things. The calorie control of the diluent gas has been described above, but it goes without saying that the same control can be performed in the case of mixing three or more types of gases.

[0021]

The accuracy guaranteed range of a flow meter such as an orifice type flow meter is generally about 15% or more of the full scale, and the accuracy of less than 15% is low. In the present invention, when the measurement range is equal to or less than a predetermined value corresponding to 15% or less of the full scale of the wide flow meter, the measurement value from the flow meter does not substantially contribute to the flow control operation, and Only the flow meter with a low measurement range provided in the capacity pipe contributes to the flow rate control. Since the accuracy is accurate in a range of at least 15% or more of the full scale of the flow meter provided in the small-capacity pipe, the flow rate control of a plurality of gases to be mixed even in a low flow rate region is higher than in the conventional example. Therefore, the calorie control of the mixed gas from the output pipe can be performed with high accuracy over almost the entire area. In the case of the first embodiment shown in FIG. 1, it is necessary to switch the control valve between the large flow rate operation and the small flow rate operation so that one of the large capacity pipe and the small capacity pipe is closed. However, in the case of the second embodiment shown in FIG. 3, such switching control is not required, so that the flow rate is not unstable at the time of switching and is more effective. Further, in the second embodiment, four flow meters are required, and the number of necessary flow meters can be reduced as compared with the first embodiment in which five flow meters are required.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a graph for explaining the operation of the embodiment shown in FIG. 1; (A) is a schematic diagram of a flow rate Q _AB of a dilution gas supplied to a burner or the like via an output pipe,
(B) is a schematic view of the flow Q _A1 of the gas A in the large pipe 3 _A (C) is a schematic view of the flow Q _a1 of the gas A in the small-capacity pipe 3 _a.

FIG. 3 is a block diagram showing another embodiment of the present invention.

FIG. 4 is a graph for explaining the operation of the embodiment shown in FIG. 3; (A) is a schematic diagram of the flow rate Q _A of the gas A in the dilution gas supplied to the burner or the like via the output pipe, and (B) is the flow rate Q _A1 of the gas A in the large capacity pipe 3 _A. schematic diagram (C) is a schematic view of the flow Q _a1 of the gas a in the small-capacity pipe 3 _a.

[Explanation of symbols]

1 _A gas A supply source 1 _B blower 3 _A , 3 _B large capacity pipe 3 _a , 3 _b small capacity pipe 4 _A , 4 _B , 4 _A ', 4 _B ' large capacity flow meter 4 _a , 4 _b small capacity of the flow meter _{5 a, 5 B, 5 a} , 5 b
Control valve _{6 A, 6 B, 6 a} , 6 b flow adjustment meter 7 _AB, 7 _ab mixer 8 mass flowmeter 9 pressure gauge 10 pressure adjusting meter 12 _Aa, 12 _Bb ratiometer 13 _AB, 13 _ab mixing ratio meter

Claims (2)

(57) [Claims] 1. A calorie control device for controlling a calorie of a mixed gas by controlling a flow rate of at least two types of gases and mixing the gases, and distributing and supplying a first gas. Large-capacity first pipe and small-capacity second pipe for distributing and supplying a second gas; large-capacity third pipe and small-capacity fourth pipe for distributing the second gas; The first and second control valves for controlling the flow rate of the first gas are respectively interposed in the third pipe and the second pipe, and the second and third control valves are respectively interposed in the third pipe and the fourth pipe. Third and fourth control valves for controlling the flow rate of gas, and supply from first, second, third and fourth pipes via first, second, third and fourth control valves Mixer means for mixing the supplied first and second gases and supplying the mixed gas to an output pipe; First and second flow meters for measuring the flow rate of the first gas flowing through the first and second pipes, and second and third flow meters for measuring the flow rates of the second gas flowing through the third and fourth pipes Third and fourth flow meters, and a fifth flow meter for measuring the flow rate of the mixed gas flowing through the output pipe.
And the flow rate of the mixed gas to be supplied from the output pipe, and the first and second gases for the mixed gas. Control means for controlling the degree of opening of the first, second, third and fourth control valves according to the first and second ratios, wherein the measured value of the fifth flow meter is a predetermined value In the following cases, the first and third control valves are controlled to be closed, and the measured values of the second and fourth flow meters are adjusted to the first and third flow rates of the mixed gas to be supplied from the output pipe. The second and fourth control valves are controlled so as to be a flow value multiplied by the ratio of 2. If the measured value of the fifth flow meter is equal to or more than a predetermined value, the second and fourth control valves are closed. And the measured values of the first and third flow meters are adjusted to the flow rate of the mixed gas to be supplied from the output pipe by the first and second ratios. As the flow rate value obtained by multiplying the calorie control apparatus, characterized in that a control means configured to control the first and third control valves. 2. A calorie control device for controlling the calories of a mixed gas by controlling the flow rates of at least two types of gases and mixing the gases, and distributing and supplying the first gas. Large-capacity first pipe and small-capacity second pipe for distributing and supplying a second gas; large-capacity third pipe and small-capacity fourth pipe for distributing the second gas; The first and second control valves for controlling the flow rate of the first gas are respectively interposed in the third pipe and the second pipe, and the second and third control valves are respectively interposed in the third pipe and the fourth pipe. Third and fourth control valves for controlling the flow rate of gas, and supply from first, second, third and fourth pipes via first, second, third and fourth control valves Mixer means for mixing the supplied first and second gases and supplying the mixed gas to an output pipe; A first flow meter for measuring an original flow rate of a first gas supplied to both the first and second pipes from a first gas supply source, and a first flow meter supplied to a second pipe. A second flow meter for measuring the flow rate of the gas, and a third flow meter for measuring the original flow rate of the second gas supplied from the second gas source to both the third and fourth pipes And a fourth flow meter for measuring the flow rate of the second gas supplied to the fourth pipe, and measurement values and outputs of the first, second, third, and fourth flow meters. According to the flow rate of the first gas in the mixed gas to be supplied from the pipe and the mixing ratio of the first gas and the second gas in the mixed gas, the first, second, third, and fourth gas are mixed. Control means for controlling the degree of opening of the control valve, wherein when the measurement value of the first flow meter is equal to or less than a predetermined value, the first control valve is closed. Controlling the second control valve so that the measured value of the second flow meter is equal to the flow rate of the first gas in the mixed gas to be supplied from the output pipe; When the measured value is equal to or more than the predetermined value, the second control valve is controlled so that the measured value of the second flow meter keeps the predetermined value, and the first gas flowing through the first pipe is output. The first control valve is controlled so as to have a flow rate of a difference between the flow rate of the first gas in the mixed gas to be supplied from the pipe and the predetermined value, and the measured values of the third and fourth flow meters are , So that the flow rate is obtained by multiplying the measurement values of the first and second flow meters by the mixing ratio.
And a control means configured to control the fourth control valve.