JPS6333608B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a combustion wick used in a liquid fuel combustor, and its purpose is to suppress the generation and accumulation of tar-like substances in the fuel vaporization part of the combustion wick, and to provide stable combustion for a long period of time. The object of the present invention is to provide a combustion wick that can maintain combustion.

A so-called siphon-vaporization type combustor sucks up liquid fuel by the capillary action of the combustion wick, and vaporizes and burns the liquid fuel from the tip of the combustion wick exposed in the vaporization chamber, that is, the surface of the fuel vaporization section. is widely used in oil stoves, oil stoves, etc. In this type of combustor, the fuel vaporization section is exposed to a high temperature and oxygen-containing atmosphere, so some of the fuel contained in the fuel vaporization section is exposed to oxidation, polymerization, etc. during combustion. The phenomenon of turning into a tar-like substance and accumulating it in the fuel vaporizer easily occurred. In particular, if trace amounts of high-boiling components are mixed into the fuel (for example, when machine oil, light oil, salad oil, etc. are mixed into kerosene), or if some of the fuel components are deteriorated (for example, if kerosene is left at high temperatures for a long period of time or exposed to direct sunlight), Oxides produced when stored under
peroxide, resin, etc.), the generation and accumulation of the tar-like substance increases significantly.

When this tar-like substance accumulates in the fuel vaporization section,
The capillary tubes on the surface or inside the fuel vaporizing section are blocked, inhibiting fuel suction and vaporization. As a result, the amount of fuel vaporized is abnormally reduced, and accordingly the amount of heat generated is significantly reduced, causing problems such as the air-fuel ratio in the combustion chamber being disrupted and the generation of odor, soot, and toxic carbon monoxide. Furthermore, at the time of ignition, the tar-like substance prevents a rapid temperature rise in the fuel vaporization section and an increase in the amount of fuel vaporization, and it takes an extremely long time to reach stable combustion. , and increased the generation of carbon monoxide, etc. Furthermore, there were dangerous situations in which the tar-like substance adhered to the wick and the metal parts that supported it, making it impossible to extinguish the fire by lowering the wick.

In order to eliminate these conventional drawbacks, the present invention
This invention suppresses the generation and accumulation of tar-like substances, and one embodiment of the present invention will be described below with reference to the accompanying drawings.

In Figure 1, 1 is the main core, which is a silica-alumina ceramic fiber (silica: alumina≒50:
50, weight ratio) and polyacrylic ester used as an example of an organic binder. 2 is a wicking core made of polypropylene cloth and connected to the main core 1. Reference numeral 3 denotes a fuel vaporization section formed on the upper part of the main core 1, which is exposed to the combustion chamber when installed in a combustor. The fuel vaporization section 3 is impregnated with a paint consisting of an inorganic pigment, anhydrous silicic acid, and a surfactant, and the ratio of this surfactant to the paint is 0.2 to 5%. 4 is a sewing thread, and 5 is an adhesive tape.

In the above configuration, liquid fuel is sucked up from the suction wick 2 to the main wick 1 and vaporized from the surface of the fuel vaporization section 3. Here, the effects of this example will be explained in detail in comparison with the flow of fuel, the conventional example, and the proportion of surfactant in the paint.

Figure 2 shows a conventional fuel vaporizer 3 made only of ceramic fibers, and Figure 3 shows a fuel vaporizer 3 impregnated with a paint consisting of an inorganic pigment, anhydrous silicic acid, and a surfactant. The percentage in the paint is 0.1%, and Figure 4 shows the fuel vaporization section 3.
Figure 5 shows the fuel vaporization section 3 impregnated with the paint, with the surfactant accounting for 1% of the paint. The percentage is set at 10%, and each cross section is shown.

That is, fuel F (solid arrow) is sucked up within the main core 1 and vaporized from the surface of the fuel vaporization section 3. At this time, in the conventional example, as shown in FIG.
is vaporized in a larger amount than at the tip of the fuel vaporizing section 3. However, trace amounts of high-boiling components and degraded components in the fuel do not easily vaporize. For this reason, high boiling point components and altered components were accumulated at this tip, changed into a tar-like substance T (white arrow) under the influence of temperature and oxygen, and accumulated. Furthermore, as shown in Figure 3, when the proportion of surfactant in the paint is 0.1%, the paint is difficult to penetrate into the silica-alumina ceramic fibers that contain a small amount of organic binder, and the paint is difficult to penetrate into the silica-alumina ceramic fibers that contain a small amount of organic binder. A large amount is easily adsorbed on the surface of part 3. For this reason, the fuel vaporization section 3
The pore size on the surface becomes too small and the amount of vaporization decreases significantly. This caused a problem in that the calorific value decreased significantly and the pores were also likely to be clogged with tar components. However, as shown in Fig. 4, when the proportion of the surfactant in the paint is 1%, the paint penetrates into the ceramic fibers to some extent, so the pore size on the surface of the fuel vaporization part 3 does not become too small. , the amount of vaporization also decreases, but the amount of heat generated does not decrease significantly. For this reason, the pore diameter on the surface of the vaporization section 3 becomes small to some extent, making it easier for the fuel to be sucked up to the high temperature surface of the vaporization section 3 due to capillary action. It is easy for the altered components to precipitate even on the surface of the vaporization section 3, which is at a high temperature, and the heat of trace amounts of high boiling point components and altered components in the fuel due to the accumulation of heat as the amount of vaporization decreases in the fuel vaporization section 3. Decomposition proceeds smoothly and no accumulation of tar-like substances occurs. Furthermore, inorganic pigments and silicic anhydride in paints are a type of oxidation catalyst, and their catalytic action accelerates this thermal decomposition action. but,
As shown in Figure 5, when the proportion of the surfactant in the paint is 10%, the paint penetrates into the ceramic fibers too much, which not only reduces the pore size on the surface of the fuel vaporization section 3, but also reduces the amount of fuel vaporization. Since the pore diameter inside the portion 3 is also small, the fuel F is insufficiently supplied to the surface of the vaporization portion, and tar is likely to accumulate inside the vaporization portion. Furthermore, since the amount of surfactant is large, the problem that the surfactant itself causes tar becomes significant.

Incidentally, Figure 6 shows the results of combustion using a suction vaporization type oil combustor. The fuel used was a mixture of white kerosene and salad oil at 0.1% by volume, and the following four types of combustion wicks were used.

(1) The fuel vaporization section 3 is made of silica-alumina ceramic fiber and is untreated.

(2) The fuel vaporization section 3 of (1) above is impregnated with a paint consisting of an inorganic pigment, anhydrous silicic acid, and a surfactant, and the ratio of the surfactant to the paint is 0.1.
%.

(3) The above (1) is impregnated with the same paint as (2),
The percentage of surfactant in the paint is 1%.

(4) The above (1) is impregnated with the paint described in (2), with the proportion of surfactant in the paint being 10%.

Comparing these four types, as shown in Figure 6,
The one with a surfactant ratio of 1% (3) is the untreated one (1), and the one with a surfactant ratio of 0.1%.
(2), the decrease in calorific value is significantly reduced compared to (4) where the proportion of surfactant is 10%.

In addition, when comparing the effect on the reduction of calorific value depending on the proportion of surfactant in the paint, as shown in Figure 7, the proportion of surfactant is 0.2 to 5.
%, it can be seen that the calorific value maintenance characteristics are extremely good.

As described above, the method for producing a combustion wick of the present invention involves impregnating a fuel vaporization part made of ceramic fiber with a paint made of an inorganic pigment, anhydrous silicic acid, and a surfactant.
And the proportion of surfactant in the paint is 0.2 to 5%.
By doing so, the generation and accumulation of tar-like substances can be suppressed, and stable combustion can be obtained over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a combustion wick according to an embodiment of the present invention, FIGS. 2 to 5 are diagrams for explaining the operation of the combustion wick, and FIGS. 6 and 7 are characteristic diagrams thereof. 1... Main core, 2... Suction wick, 3... Fuel vaporization section.

Claims (1)

[Claims] 1 A small amount of organic binder is added to ceramic fibers to form a porous fuel vaporization section, and at least a portion of the fuel vaporization section is coated with inorganic pigments and silicic anhydride to reduce the pore size on the surface of the fuel vaporization section. A method for manufacturing a combustion wick, which is impregnated with a paint consisting of a surfactant and a surfactant, and in which the surfactant accounts for 0.2 to 5% of the paint, and permeates into the fuel vaporization section.