JPS6057119A - Liquid fuel combustion device - Google Patents

Abstract

PURPOSE:To improve a temperature distribution condition and to enable uniform heating and vaporization of liquid fuel, by a method wherein a resistance wire is embedded in the interior of a heat resisting ceramic flat plate, the outer peripheral part is surrounded with a bankformed frame, and a thin heat resisting ceramic plate is placed on the upper surface of a liquid fuel evaporating plate. CONSTITUTION:When the surface temperature of a liquid fuel evaporating plate 5 is increased to 250-300 deg.C, an ignition heater 15 is energized, and liquid fuel, simultaneously, is fed onto the liquid fuel evaporating plate 5 to evaporate the fuel on the surface of the evaporating plate. The air for combustion flows through the circumference from the base of the liquid fuel evaporating plate 5, and is fed along a wall around a fuel-air mixture outlet 17, and the liquid fuel evaporated on the liquid fuel evaporating plate 5 is mixed with the air for combustion to feed the mixture to a combustion chamber 10 located above the evaporating plate. A flame is formed on the upper surface of a catalyst A13 with the aid of an ignition heater 15, combustion is gradually penetrated in the inner surface of the catalyst A13 by dint of the heat to be moved to catalyst combustion. A ceramic heater itself forms a liquid fuel evaporating part, and this decreases a time wherein liquid fuel is forced into a condition of being evaporated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is a liquid fuel combustion device for a liquid fuel combustion device that vaporizes liquid fuel on a hot plate, mixes it with gas, and then sends it to a combustion section for combustion. This relates to the fuel vaporization section.

Structure of a conventional example and its problems A conventional liquid fuel combustion apparatus of this type has a sheathed heater 2 built into a liquid fuel vaporizing cylinder 1, as shown in FIGS. 1 and 2. Alternatively, a flat plate-shaped seven-ramic heater 3 was brought into close contact with the back surface of the liquid fuel vaporizing cylinder 1. In this configuration, the liquid fuel vaporization cylinder 1 with a large heat capacity (usually thick aluminum or cast iron with a large heat capacity is used to uniformly heat the entire surface of the vaporization cylinder) is heated in contact with the sheathed heater 2 or the ceramic heater 3. be done. Therefore, it takes a long time to heat the fuel carburetor 1 to a predetermined temperature.
It also requires a heater. Furthermore, since the vaporizer cylinder cannot be heated indirectly, the size of the vaporizer cylinder cannot be made compact.
Since the vaporizing cylinder itself cannot be heated to such a high temperature, there is also the potential problem of tar adhesion.

OBJECTS OF THE INVENTION The present invention solves the problems of the prior art.
i By using the liquid fuel vaporizing part of the liquid fuel combustion device itself as a heater, various defects mentioned in 1. The purpose is to uniformly heat and evaporate.

Structure of the Invention In order to achieve this object, the present invention horizontally installs a liquid fuel vaporization plate in the center of a liquid fuel vaporization chamber, in which a resistance wire is embedded inside a heat-resistant ceramic flat plate and the outer periphery is surrounded by an embankment-like frame. The structure is such that liquid fuel is supplied in two parts and evaporated. Furthermore, on the two sides of this liquid fuel vaporization plate, place a thin heat-resistant ramic plate.
Alternatively, the ceramic plate is covered with an inorganic heat-resistant cement.1 With this structure, fuel is not supplied to the liquid fuel vaporization plate itself, but to a thin plate of heat-resistant ceramic placed on top of it. Because the fuel is being supplied to the liquid fuel vaporizing plate, which is the ceramic heater itself, the intense heat fluctuations become more frequent, and the cracking caused by the thermal shock of the ceramic heater, which is common with this type of vaporizing plate, is eliminated.
Furthermore, by making the heat-resistant ceramic plate have continuous small bubbles, evaporation can be made smoother.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. Since FIG. 4 is a partially detailed view of FIG. 3, the same members are given the same numbers.

In FIG. 3, a disk-shaped liquid fuel vaporization plate 5 is installed horizontally in the central space of a liquid fuel vaporization chamber 4 made of a stainless steel plate. The liquid fuel vaporization plate 5 is made of heat-resistant alumina, and has a resistance wire 6 embedded therein. The circumference of the liquid fuel vaporization plate 5 is surrounded by an embankment-like frame 7, and a ceramic plate 8 made of a thin porous cordierite plate is bonded to the surface of the liquid fuel vaporization plate 50 with alumina cement 9. has been done. Liquid fuel vaporization chamber 4
The upper part of the combustion chamber 10 becomes a combustion chamber 10, and inside thereof, a rectifying plate 12 with small holes 11, a catalyst body A13, and a catalyst body B14 are arranged in order with a gap of 5 mm from the bottom. There is no ignition between the catalyst body A13 and the catalyst body B14.
15 is installed. There is a combustion air inlet 16 in the center of the lower part of the liquid fuel vaporization chamber 4, and a fuel-air mixed gas outlet 17 is partially located in the center of the liquid fuel vaporization chamber 4 and protrudes toward the liquid fuel vaporization plate 5 in an inverted truncated conical shape. Air mixture gas outlet 17
A shielding plate 18 is placed between the rectifying plate 12 and the rectifying plate 12. Furthermore, in order to supply liquid fuel to the surface of the liquid fuel vaporization plate 5, a liquid fuel supply pipe 1 is passed through the wall of the liquid fuel vaporization chamber 4 from the outside.
9 has been set up.

” The operation in the configuration described in item 1 will be explained.

First, the liquid fuel vaporization plate 5 is energized, and its surface temperature reaches 25.
When the temperature reaches 0°C to 300°C, the ignition heater 15 is energized. At the same time, liquid fuel is supplied to the liquid fuel vaporizing plate 5 by an electromagnetic pump (not shown) through the liquid fuel supply pipe 19, and is vaporized on the surface thereof.

On the other hand, the combustion air sent in from the combustion air inlet 16 hits the bottom of the liquid fuel vaporization plate 5, passes around it, and runs along the wall around the fuel-air mixed gas outlet 17, which projects downward in an inverted truncated cone shape, to the liquid fuel vaporization plate. 5- Send it to the next day. The liquid fuel vaporized on the liquid fuel vaporization plate 5 and the combustion air are mixed well and sent to one combustion chamber 1o. On the way, it is uniformly mixed by the shielding plate 18 and the rectifying plate 12, and is evenly supplied to the catalyst body A13 and the catalyst body B14, where it is catalytically burned on the surface thereof. At the beginning of combustion, a flame is formed on two sides of the catalyst body A13 by the ignition heater 15, and the heat causes the p
Combustion gradually sinks into the inner surface of the catalyst body A13 and transitions to catalytic combustion. Therefore, the main catalytic combustion is carried out by the catalyst body A13, and the catalyst body B14 burns the unburned components that have slipped in the catalyst body A13, or has a heat retaining function for the catalyst body A13.

Although an example in which the present invention is applied to a catalytic combustor has been shown as an example, a combustor employing a normal flame combustion method is also within the scope of the present invention, regardless of the combustion method.

Effect of the invention As described above, the liquid fuel combustion apparatus of the present invention is used. In this case, the following effects can be obtained.

(1) Unlike conventional liquid fuel vaporization cylinders, where a large metal block is indirectly heated by a sheathed heater or ceramic heater, the ceramic heater itself serves as the liquid fuel vaporization part. The time it takes for liquid fuel to become evaporable has been considerably shortened, whereas conventionally it took 2 to 3 minutes, it can now be reduced to within 20 seconds.

2. Since the heating part is only the ceramic plate, the required power is small, and for example, the power required for the conventional system, which was 200W to 100W, can be reduced to 50W or less, which is 1/4 of that required.

a) The liquid fuel vaporization part is extremely simple and compact in structure, so it was able to be reduced to about 1/2 of the conventional size.

G+1 No matter which method is used in the hot plate vaporization method, the temperature range is generally fixed, and precipitation of cool to some extent is unavoidable within that temperature range. Precipitator) V raises the temperature in the presence of air (600°C to 800°C)
C) In particular, it can be easily removed. Conventional vaporizing parts using metal blocks cannot raise such temperatures due to their structure and the nature of the additive, but ceramic heaters can easily raise the temperature and prevent tar precipitation. did it.

(5) Liquid fuel is not supplied directly to the surface of the ceramic liquid fuel vaporization plate, but rather to a thin ceramic plate that is in close contact with the surface of the liquid fuel vaporization plate, which prevents local rapid cooling of the ceramic heater surface. , it was possible to prevent destruction due to thermal shock.By making the thin ceramic plate into a porous material, the capillary action or the wettability of liquid fuel could be used to greatly reduce the evaporation phenomenon. However, even if a thin ceramic plate were to break, unlike a ceramic heater, there would be little negative impact.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of a conventional liquid fuel combustion device, FIG. 3 is a cross-sectional view of a liquid fuel combustion device that is an embodiment of the present invention, and FIG. 4 is a sectional view of the liquid fuel vaporization section 9.・It is a sectional view shown. 5...Liquid fuel vaporization plate, 6...Resistance wire,
7... Frame, 8... Ceramic plate, 9... Alumina cement (... Name of agent: Patent attorney Toshio Nakao and 1 other person 1st)
Figure 2

Claims (1)

[Claims] (1) A resistance wire is embedded inside a heat-resistant ceramic flat plate and the outer periphery is surrounded by a frame.
A liquid fuel combustion device in which a ceramic plate having a thickness of mm is placed, and the ceramic plate is used as a part for vaporizing liquid fuel. 2. The liquid fuel combustion device according to claim 1, wherein the ceramic plate has continuous small bubbles and exhibits capillary action with respect to the liquid fuel, and the ceramic plate is fixed with an inorganic heat-resistant cement. (2) The liquid fuel combustion device according to claim 1, wherein the temperature of the liquid fuel vaporization section is temporarily raised to 400°C to 800°C after the steady combustion is finished.