JPH0253610B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a combustion device such as a diesel engine that mixes gas into liquid fuel and injects it into a combustion chamber for combustion. The present invention relates to a combustion device in which gas is mixed with fuel through a pressure equalization tank that communicates with both a supply system and a fuel supply system, and once dissolved in the fuel, it is injected into a combustion chamber and burned.

[Prior Art] A method has already been disclosed in which gas is mixed into fuel, the pressure of the gas is increased by a fuel injection pump, and the mixture is injected into a combustion chamber (see Japanese Patent Publication No. 33992/1983). According to this method, gas is mixed into the fuel, and when the fuel is brought to high pressure by the fuel injection pump, the gas dissolves in the fuel, and when it is injected from the injection nozzle, the dissolved gas is suddenly generated. . Therefore,
The injected fuel particles are destroyed by the generated gas, resulting in atomization of the fuel particles, improving the mixing of fuel and gas, and reducing the amount of carbon in the exhaust gas.
It has the advantage of reducing HC and CO.

However, although the above method is effective as a measure against exhaust gases, the fuel pressure and gas pressure must be accurately controlled in order to mix gas appropriately and quantitatively into the supplied fuel. However, since fuel is normally fed by a feed pump and gas is fed after being pressurized by a compressor, precise pressure control of both is difficult and pulsation occurs.

As a countermeasure against these drawbacks, a pressure regulator, a pulsation prevention tank, etc. were individually provided for each, but this was still insufficient.

In order to eliminate the above-mentioned drawbacks, a method has been disclosed in which a pressure equalizing tank is provided that communicates with both the gas supply system and the fuel supply system (Japanese Patent Publication No. 60-33993). FIG. 3 shows a conventional example of such a pressure equalizing tank, in which a fuel supply system F is provided with a fuel tank 2, a feed pump 3, and a pressure regulator 30, and is connected to the pressure equalizing tank 1. Gas supply system G
is equipped with a compressor 25 and a pressure regulator 31, and is connected to the pressure equalization tank 1. Then, the fuel and gas fed by the feed pump 3 and the compressor 25 are temporarily stored in one pressure equalization tank 1 and have an equal pressure. For this reason, each pressure regulator 3 of the fuel supply system F and gas supply system G provided downstream of the pressure equalization tank 1
2 and 33 are configured to adjust the pressures of the fuel and gas to improve the control accuracy of the pressure difference when mixing the gas into the fuel. Note that 1a is a float for a level switch.

[Problems to be Solved by the Invention] However, according to the method of mixing gas and liquid fuel through the pressure equalizing tank 1, the gas is supplied by the compressor 25 while the pressure is adjusted by the pressure regulator 31. The problem is that it has to be done.

Therefore, the present invention first improves the gas supply system and uses LPG (liquefied gas) as the injection gas.
By utilizing the vaporization pressure of LPG, the structure can be simplified by eliminating the need for a gas pre-pressure device (compressor).Furthermore, it promotes the fluidization of liquid fuel and improves combustion while LPG acts as a combustion aid. The purpose is to provide a combustion device with

[Means for Solving the Problems] As shown in FIGS. 1 and 2 of the embodiment drawings, the present invention gasifies liquefied LPG sealed in a high-pressure cylinder 4 into a pressure equalization tank 1. The gas supply system G to be supplied and the liquid fuel supply system F are connected, and the gasified LPG and liquid fuel in the pressure equalization tank 1 are respectively drawn out from the pressure equalization tank and mixed, and this mixed gas-liquid mixed fuel is produced. The combustion apparatus is characterized in that the pressure of the fuel is appropriately increased by a fuel injection pump 15, and the fuel is injected into a combustion chamber 14 through an injection nozzle 16 for combustion.

[Function] In the combustion apparatus of the present invention configured as described above, since LPG is used as the injected gas and its vaporization pressure is utilized, there is no need to prepress the gas by the compressor, and the LPG and liquid fuel are evenly distributed. Since it is stored in the pressure tank 1, the pressure can be maintained at the same level.

In addition, since the gasified LPG and liquid fuel, which have become equal in pressure, are both at high pressure due to the vaporization pressure of LPG, stirring and fluidization by mixing the two is promoted, which promotes fluidization of the fuel. Combustion efficiency is greatly improved since LPG can be used as a combustion aid.

[Example] An example of the present invention will be described below based on FIG.

In this figure, reference numeral 1 denotes a pressure equalization tank, into which liquid fuel and gasified LPG, ie, propane gas, are fed and mixed by a liquid fuel supply system F and a gas supply system G.

The fuel supply system F is provided with a fuel tank 2 and a feed pump 3, and is connected to the pressure equalization tank 1.The gas supply system G is provided with a high pressure cylinder 4 filled with liquefied LPG, and is connected to the pressure equalization tank 1. has been contacted.

Note that since the feed pump 3 that pumps the liquid fuel at a pressure higher than the set pressure in the pressure equalization tank 1 was used, the pressure regulator provided in the fuel supply system F was omitted. Further, a level switch (not shown) consisting of a float is provided in the pressure equalizing tank 1, and controls the motor of the feed pump 3, thereby setting the fuel level in the pressure equalizing tank 1 to a predetermined value.

Furthermore, a liquid fuel outflow pipe 5 is provided below the pressure equalizing tank 1 and communicates with a gas mixing chamber 6 .
Further, a gas outflow pipe 7 is provided above the pressure equalizing tank 1 and communicates with the gas mixing chamber 6. The gas mixing chamber 6 is constituted by a stirring device (not shown) using a known ventilate mechanism or the like, and an LPG mixed fuel outflow pipe 8 is provided downstream of the gas mixing chamber 6. The entire or part of the mixed fuel outflow pipe 8 is a mixing path 9 such as a spiral flow path pipe.

An injection pump 1 is provided downstream of the mixing path 9.
5 and an injection nozzle 16 that injects fuel into the combustion chamber 14.
is provided. In the middle of the line connecting the injection pump 15 and the injection nozzle 16, a reflux pipe 17 having an auxiliary fuel tank 19 in the middle is branched off and connected to the fuel tank 2.

FIG. 2 shows yet another embodiment of the invention. In this embodiment, a U-shaped pressure equalizing tank 1 is provided, one of the pipes 1a
A fuel supply system F and a gas supply system G are connected to the other pipe 1b, and a recirculation pipe 17 for the remaining circulating fuel supplied to the injection nozzle 16 by the injection pump 15 is connected to the other pipe 1b. Note that 18 is a feed pump for refluxing the circulating fuel.

Furthermore, in Figs. 1 to 3, 20, 21,
22, 23, and 24 are on-off valves.

In the present invention configured as described above, LPG is injected into the pressure equalizing tank 1 from the high pressure cylinder 4 via the on-off valve 21 by vaporization pressure, and the fuel tank 2
The liquid fuel inside is transferred to equalization tank 1 by feed pump 3.
The pressure is fed into the pressure equalizing tank 1 at a pressure higher than the set pressure in the pressure equalizing tank 1. Gasification delivered in this way
LPG and liquid fuel are once stored in the pressure equalization tank 1 and have equal pressure.

The LPG and liquid fuel in this pressure equalizing tank 1 are controlled by an on-off valve 22, a fuel outflow pipe 5 and an on-off valve 2, respectively.
3. Introduce the gas into the gas mixing chamber 6 via the gas outflow pipe 7.

Equal pressure gasified gas introduced into the gas mixing chamber 6
Since LPG and fuel are under high pressure due to the vaporization pressure of LPG, many fine LPG bubbles are evenly distributed in the liquid fuel, and the liquid fuel and LPG are mixed in the gas mixing chamber 6. Furthermore, mixing is promoted in the mixing path 9, and fluidization of the fuel is promoted.

In this way, the almost completely mixed LPG fuel is injected from the injection nozzle 16 into the combustion chamber 14 and combusted.

Although the above description has been made regarding a diesel engine, the present invention can also be effectively utilized in continuous combustion in gas turbines, boilers, and the like.

[Effects of the Invention] As explained above, the present invention employs LPG as the injection gas, uses the vaporization pressure of LPG to introduce it into a pressure equalization tank, equalizes the pressure, and then mixes it. , easy to operate and relatively simple configuration that does not require gas pre-pressure, allows a large number of
The fine bubbles of LPG are evenly distributed, which can promote the mixing of LPG into the liquid fuel and the fluidization of the fuel.

Therefore, efficient complete combustion can be carried out using LPG as a combustion aid, and low distillate oil and fuel with poor combustibility can be used as liquid fuel.

Furthermore, by using a U-shaped tank as the pressure equalization tank, bubbles can be easily separated from the refluxed fuel when the circulating fuel is refluxed, making it easy to reuse the fuel.

Therefore, an easy-to-operate device that uses the vaporization pressure of LPG such as propane gas can improve the reliability of gas mixing into fuel, reduce carbon, HC, and CO in exhaust gas, and Practical effects such as improved fuel efficiency can be expected.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of a combustion device showing one embodiment of the present invention, FIG. 2 is a system diagram of a combustion device showing another embodiment of the invention, and FIG. 3 is a combustion system diagram showing a conventional example. It is a system diagram of a device. 1... Equal pressure tank, 2... Fuel tank, 3... Feed pump, 4... High pressure cylinder, 6... Gas mixing chamber, 8
...LPG mixed fuel outflow pipe, 9...mixing path, 14...combustion chamber, 15...injection pump, 16...injection nozzle.

Claims (1)

[Claims] 1 A gas supply system that gasifies and supplies liquefied LPG sealed in a high-pressure cylinder is connected to a liquid fuel supply system in a pressure equalization tank, and the gasified LPG and liquid in the pressure equalization tank are connected. A liquefied fuel addition combustion device characterized in that the gas-liquid mixed fuel is drawn out from a pressure equalizing tank and mixed, and the mixed gas-liquid fuel is injected into a combustion chamber through an injection nozzle and combusted. 2. A patent claim in which the pressure equalizing tank is U-shaped, one pipe of the U-shape is connected to a liquid fuel supply system and a gas supply system, and the other pipe is connected to a gas-liquid mixed fuel reflux pipe. The liquefied fuel addition combustion device according to item 1.