JPH0141091Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a liquid heating device, and more particularly, to a pulse combustion type liquid heating device in which a heating tail pipe of a pulse combustion device is immersed in a liquid to be heated in a tank. .

Regarding the above-mentioned pulse combustion type liquid heating device, the applicant of the present application has disclosed, for example, Utility Application No. 1983-96038 (filed on June 24, 1981, published on December 27, 1981,
-196739), etc., and when starting the device (starting combustion), combustion air is forcibly supplied by a fan etc., and ignition is forcibly ignited by an ignition plugge etc. However, during steady combustion operation after startup, energy-saving operation is possible because no energy is required for supplying combustion air or ignition, and high-load combustion is possible, so the equipment itself is relatively small compared to its capacity. Can be configured compactly,
In addition, since it is an explosive combustion type, the exhaust pressure of the combustion gas is high even though fuel gas and combustion air with low supply pressure are used, so high-speed exhaust is possible even though the exhaust path is configured to be very narrow. , not only has various advantages such as extremely high heating efficiency can be obtained when the exhaust passage is configured with a thin tail pipe and is used as an immersion pipe for heating fluid, but also Immediately before explosive combustion, part of the combustion gas flows back into the combustion chamber from the exhaust passage, resulting in a certain degree of exhaust gas recirculation combustion occurring spontaneously.
NOX combustion (usually 35 to 45 ppm at O ₂ = 5% conversion value)
However, in recent years, various disadvantages such as the need for extremely high supply pressures of fuel gas and combustion air have emerged. It is increasingly being used in place of the conventional submerged combustion type liquid heating device.

The purpose of the present invention is to improve the pulse combustion type liquid heating device, which has the various excellent characteristics described above, into one with even higher thermal efficiency.

In order to achieve the above object, the pulse combustion type liquid heating device according to the present invention has the basic configuration described at the beginning, and the tail pipe includes:
The exhaust pipe is connected to an exhaust pipe that can be switched between a first state in which the combustion exhaust gas passing through it is directly released into the atmosphere and a second state in which it is introduced into the heated liquid in the tank.

The functions and effects exhibited by the above characteristic configuration are as follows.

That is, unlike conventional configurations, the combustion exhaust gas that has passed through the tail pipe and has undergone a heating action on the liquid is not always wastefully discharged directly into the atmosphere as it is, but the combustion exhaust gas is released into the heated tank as needed. By injecting it into the liquid, the residual heat of the combustion exhaust gas can be effectively reused for heating the liquid.
This made it possible to significantly improve the overall thermal efficiency of the device. Additionally, in addition to the conventional immersion tube heating method using a tail pipe, we have also made it possible to use the so-called submerged combustion method, in which combustion exhaust gas is injected into the liquid, so that the temperature distribution of the liquid in the tank is similar to that of the conventional pulse heating method. Compared to combustion-type liquid heating devices, we were able to achieve much more uniformity. In addition, in this invention, in order to inject the combustion exhaust gas into the liquid, the high exhaust pressure itself originally possessed is effectively used, so it does not work as well as the conventional submerged combustion type heating device. No special high-pressure blower required. In addition, in the present invention, the combustion exhaust gas from the tail pipe is not always injected into the liquid, but is configured so that it can be switched between being released into the atmosphere and being injected into the liquid. When starting up a pulse combustion device or when the liquid to be heated cannot be directly heated by combustion exhaust gas, the exhaust pipe can be switched to the atmosphere release state at will, making it possible to increase the size of the startup blower. Moreover, it is extremely versatile and is not subject to usage restrictions depending on the type of liquid to be heated.

Embodiments of the pulse combustion type liquid heating device according to the present invention will be described below with reference to the drawings.

As shown in the overall schematic diagram of FIG. 1, a burner head 1 and a combustion chamber 2 connected thereto constitute a combustion section A.
A fuel gas supply path B and a combustion air introduction path C are introduced and connected, and an exhaust path D for high temperature combustion gas is led out from the combustion chamber 2.

To explain in detail the specific configuration near the combustion section A,
As shown in FIG. 2, the burner head as a gas distributor is provided on the upstream side of the combustion chamber 2 having the starting spark plug 3, and
The fuel gas supply path B is connected to the upstream side of the burner head 1 via a valve mechanism 4 called a gas flapper for preventing the backflow of explosive combustion gas from the combustion chamber 2. The combustion air introduction passages C are connected to each other via a valve mechanism 5 called an air flapper to prevent the backflow of the explosive combustion gas, and on the downstream side of the combustion chamber 2, the explosive combustion gas is A tail pipe 6 is extended to heat a surrounding object to be heated (for example, a liquid) by passing it through the combustion chamber 2 so as to discharge it by force. In the burner head 1, an air passage 1A is formed in the shape of a ventilated tube, and a gas outlet 1B is formed in the throat of each of the ventilated tubular air passages 1A. The fuel gas is configured to be strongly sucked in and mixed well with the air by the differential pressure between the low pressure generated at the throat as the air passes through and the gas supply pressure.

In detail, the configuration of the air flapper valve mechanism 5 for preventing backflow with respect to the combustion air introduction path C is that a plurality of ventilation holes 5a are arranged in parallel in an annular manner on a disc-shaped valve seat 5A, while a central ventilation hole 5c is provided. A plurality of ventilation holes 5b are arranged in parallel around the entire circumference of the ring-shaped seat 5B, and the seat 5B is connected to the valve seat 5A by a large number of bolt-nut-shaped connecting members 5c. The valve seat 5A is connected integrally with the valve seat 5A isolated for an appropriate period of time.
and a ring-shaped sliding valve body 5D between the catch seat 5B,
The connecting members 5C are installed in a state where they are positioned in the radial direction, and when the inside of the combustion chamber 2 becomes positive pressure due to explosive combustion in a steady state, the catch seat 5
The pressing force acting on the valve body 5D from the central ventilation hole 5c and the peripheral ventilation hole 5b of B causes the valve body 5D to be moved to the valve seat 5A.
conversely, when the inside of the combustion chamber 2 becomes negative pressure immediately after explosive combustion, the valve body 5D is closed by the suction force acting from the central ventilation hole 5c and the peripheral ventilation hole 5b of the catch seat 5B. Press the valve mechanism 5 against the catch seat 5B.
It is configured to open. Then, a heat-resistant and pressure-resistant disk 5E equipped with a central ventilation hole 5c is opposed to each other with its blind portion covering all of the ventilation holes 5b of the catch seat 5B, respectively, and the rod-shaped connecting member 5C... It is configured to suppress heating of the valve body 5D due to radiant heat transfer from the combustion chamber 2, and to relieve the enormous dynamic pressure applied to the valve body 5D from the combustion chamber 2 during explosive combustion. In addition, by combining the configuration in which the ventilation holes 5a of the valve seat 5A and the ventilation holes 5b of the catch seat 5B are arranged with a phase difference in the circumferential direction so that they do not face each other, the protection of the valve body 5D can be more effectively achieved. .

The structure of the backflow prevention gas flapper valve mechanism 4 for the fuel gas supply path B is also basically the same as the air flapper valve mechanism 5.

As shown in FIG. 1, the fuel gas supply path B includes, in order from the upstream side, a fuel gas supply path V ₀ , a governor G, a flow rate adjustment solenoid valve Vc, a safety control solenoid valve Vs,
A gas cushion tank 7, an orifice 8, and the gas flapper valve mechanism 4 are provided.

Further, the combustion air introduction path C is provided with a starting electric fan F, a resonant intake silencer 9, an air action tank 10, and the air flapper valve mechanism 5 in this order from the upstream side.

The exhaust path D includes, in order from the upstream side, the heating tail pipe 6, the decoupling chamber 11 for absorbing and mitigating exhaust gas vibrations accompanying explosive combustion and stabilizing resonance due to combustion;
An exhaust pipe 12 is provided which extends and has its tip branched into two paths.

That is, the exhaust pipe 12 has a first exhaust pipe 12A that is open to the atmosphere via a first on-off valve V ₁ and a resonant exhaust-side silencer 13 at its tip side, a second on-off valve V ₂ and a dispersion side silencer 13 . It is branched into a second exhaust pipe 12B that is open into the heated liquid L in the tank 16 via the plate 14. The first and second on-off valves V ₁ and V ₂ can be controlled to open and close reciprocally through the control mechanism M, that is, the combustion exhaust gas that has passed through the tail pipe 6 and the decoupling chamber 11 It is configured to be switchable between a first state in which the liquid is directly discharged into the atmosphere and a second state in which it is introduced into the heated liquid L in the tank 16. In this embodiment, the control mechanism M is configured to automatically switch the exhaust pipe 12 to the first state when the pulse combustion device that operates the fan F is activated, and to control the control mechanism M to automatically switch the exhaust pipe 12 to the first state, and to control the The exhaust pipe 12 is configured to automatically switch to the second state during steady combustion in the combustion apparatus. However, even in the steady combustion state, the configuration is such that manual priority is given so that the combustion exhaust gas can be forcibly switched to the first state in which the combustion exhaust gas is released into the atmosphere. This is because in some cases, for example, when the liquid to be heated is alkaline, it is not preferable to directly introduce weakly acidic (about pH 6) exhaust gas. In the figure, 15
is the liquid level fluctuation mitigation plate.

In this embodiment, as shown in the figure, not only the heating tail pipe 6 but also the combustion chamber 2, the large spring chamber 11, etc. are immersed in the heated liquid L, thereby reducing heat radiation loss. We are trying to suppress this as much as possible. In addition, the second
The exhaust pipe 12B does not need to be provided with an exhaust silencer because the exhaust noise is alleviated by being immersed in the liquid, so that the structure can be prevented from becoming complicated.

Next, the operation of the pulse combustion device will be summarized.

When a start-up command is issued to the control mechanism M, the first on-off valve V ₁ is opened and the second on-off valve V ₂ is closed. and combustion air are forced into the combustion chamber 2 at an appropriate mixing ratio through the burner head 1, and an explosion is caused within the combustion chamber 2 by the spark plug 3. Then, a negative pressure suction force is generated in the combustion chamber 2 based on the exhaust kinetic inertia of the combustion gas after the explosive combustion of the gas-air mixture in the combustion chamber 2, and thereby the fuel gas and combustion Appropriate amounts of air are mixed into the combustion chamber 2 via the backflow prevention valve mechanisms 4 and 5, and a portion of the exhaust combustion gas flows back into the combustion chamber 2 from the tail pipe 6. As a result, the explosion combustion cycle of the gas-air mixture is continuously repeated using the retained heat of the backflow combustion gas.

When this pulse combustion becomes stable, the operation of the starting fan F and the spark plug 3 is stopped, and the first on-off valve V ₁ is closed and the second on-off valve V ₂ is opened. It will be done.

FIG. 3 shows another embodiment, in which the indirect heating part of the pulse combustion device consisting of the combustion chamber 2, tail pipe 6, large spring chamber 11, etc. is arranged on the high temperature heating tank 16A side, while the dispersion plate 14 The indirect heating part and the direct heating part are placed in separate liquid tanks 16A and 16B, such as by disposing the direct heating part by injecting the exhaust gas into the liquid, which consists of the liquid level fluctuation mitigation plate 15, etc., on the low temperature heating tank 16B side. They are distributed throughout the country.

[Brief explanation of the drawing]

The drawings show an embodiment of the pulse combustion type liquid heating device according to the present invention, in which Fig. 1 is a general schematic diagram, Fig. 2 is a detailed side sectional view of the main part, and Fig. 3 is an overall diagram of another embodiment. It is a schematic configuration diagram. 6... Tail pipe for heating, 12... Exhaust pipe,
16... Tank, L... Liquid to be heated, M... Control mechanism.

Claims (1)

[Claims for Utility Model Registration] A pulse combustion type liquid heating device in which a heating tail pipe 6 of the pulse combustion device is immersed in a heated liquid L in a tank 16, the tail pipe 6 The first state and tank 1 discharge the combustion exhaust gas directly into the atmosphere.
6. A pulse combustion type liquid heating device characterized in that an exhaust pipe 12 is connected to a second state in which the liquid to be ignited is injected into the liquid L in the combustion liquid L in the combustion liquid L in the combustion liquid L in the combustion liquid L in the pulse combustion type liquid heating device. A control mechanism M that automatically switches the exhaust pipe 12 to the first state when the pulse combustion device is started, and automatically switches the exhaust pipe 12 to the second state during steady combustion of the pulse combustion device.
A pulse combustion type liquid heating device according to claim 1, characterized in that the device is provided with: