JPH0689880B2 - Air temperature / hot water combined LPG air gas production plant - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a liquefied propane gas, liquefied butane gas, or other liquefied petroleum gas (LPG) that is vaporized and mixed with air to produce propane air gas or butane air gas (the present specification). In the book "LP
G air gas ". ) Is manufactured, and in particular, it relates to an air-temperature / hot-water LPG air gas production plant equipped with an air-temperature / hot-water vaporizer that can be used even in cold regions or in extremely cold seasons.

2. Description of the Related Art The applicant of the present application, as disclosed in Japanese Patent Laid-Open No. 61-180099, vaporizes liquefied propane gas in an air-temperature type forced vaporizer and mixes it with air to produce 13A propane air gas. A manufacturing plant was proposed.

The air-heated forced vaporizer used in this 13A propane air gas production plant has a finned heat transfer tube made of aluminum with a high heat transfer efficiency similar to that of liquid oxygen or liquid nitrogen. heat transfer coefficient: 25.3kg / m ³ · h
liquefied propane gas produced in the vaporizer, the liquefied propane gas flowing into the vaporizer lowers the boiling point of the liquefied propane gas by reducing the pressure at the liquid inlet portion of the vaporizer, that is, 1 kg / cm 2.
^In the case of 2.G, it is set to about -27 ° C, and a temperature difference from the atmospheric temperature
It has a structure in which it is gasified by a heat transfer tube with fins.

As described above, the air-temperature type forced vaporizer uses the atmospheric temperature as a heat source and has a structure for evaporating the liquefied propane gas due to the temperature difference between the atmospheric temperature and the liquid temperature of the liquefied propane gas.
This 13A propane air gas production plant has a feature that the initial cost for the heat source equipment for evaporation is zero, and as a result, city gas can be produced and supplied at an extremely low cost.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-mentioned 13A propane air gas production plant by the applicant, the design capacity of the air-temperature type forced vaporizer has an atmospheric temperature of −8 in consideration of the initial cost and running cost of equipment. 4 ° C or more, cloudy and no wind
Time continuous operation is standard, and therefore, it may be difficult or, in some cases, impossible to use in cold regions or severe cold seasons.

For example, in Japan, for example, in the area south of Kanto, the air-cooled forced vaporizer with the above design specifications is sufficient, but in other areas the vaporization capacity in winter will decline. Become. According to the result of the applicant's experimental research, the northeastern part of Kanto is the northern limit.

In addition, for example, even in the south of Kanto, frost on the carburetor is severe when the plant continues to operate continuously, so a spare air-temperature type forced carburetor for switching is required, which increases the initial cost. .

If a separate hot water vaporizer is installed as a measure against cold regions or severe cold seasons, the initial cost will be further increased.

Furthermore, in Japan, as a city gas production plant,
Attempts have also been made to produce butane air gas using liquefied butane gas as a raw material.

Liquefied butane used in the butane air gas plant has a high boiling point, that is, it is about 15 ° C. in the case of 1 kg / cm ² · G,
It is necessary to vaporize with a vaporizer that uses electricity, hot water or steam as a heat source, and the use of a conventional air temperature type forced vaporizer such as that used in the above-mentioned 13A propane air gas production plant Was impossible.

A main object of the present invention is generally air temperature type in summer, hot water type in winter, etc., and switching operation is possible depending on climatic conditions etc., and it is also suitable in cold regions or severe cold season.
It is an object of the present invention to provide an air-temperature / hot-water dual-use LPG air gas production plant equipped with an air-temperature / hot-water dual-use vaporizer capable of vaporizing LPG and capable of efficiently producing LPG air gas.

Another object of the present invention is to increase vaporization capacity and evaporation capacity and to efficiently remove frost formed on a device due to continuous operation and the like, and to require a preliminary vaporizer for switching. Equipped with an air / hot water type vaporizer without
It is to provide an air temperature / hot water combined type LPG air gas production plant capable of efficiently producing G air gas.

Means for Solving the Problems The above-mentioned objects are achieved by the air-temperature / hot-water dual-use LPG air gas production plant according to the present invention. In summary, the present invention vaporizes liquefied petroleum gas, which is liquefied propane gas or liquefied butane gas, with an air temperature / hot water vaporizer, and mixes the vaporized liquefied petroleum gas with air to produce LPG air gas. In the plant, the air-heated / hot-water vaporizer comprises a supply-side manifold, a discharge-side manifold, a plurality of transmissions connected at one end to the supply-side manifold and at the other end to the discharge-side manifold. An air temperature characterized by having a heat tube and a heating tube wound around the outside of the supply side manifold and supplied with hot water inside.
This is a hot water combined LPG air gas production plant. Preferably, the heating tube has a rectangular cross section, and the hot water is water mixed with an antifreeze liquid.

EXAMPLES Next, the LPG air gas production plant according to the present invention, and particularly the air temperature / hot water combined vaporizer preferably used in the production plant will be described in more detail with reference to the drawings.

FIG. 1 shows an embodiment of an air-temperature / hot-water type vaporizer which constitutes a main part of the present invention. According to the present embodiment, the air-heated / hot-water type vaporizer 1 has a supply-side manifold 2 and a discharge-side manifold 4, and a heat transfer tube 6 is provided between the supply-side manifold 2 and the discharge-side manifold 4. Are connected in large numbers. Further, in order to improve the heat transfer (heat absorption) effect of the heat transfer tube 6, a heat transfer fin 8 is arranged around the heat transfer tube 6.

Further, according to the present invention, a heating tube 21 is wrapped around the outer perimeter of the supply manifold 2, as better understood with reference to FIG. The heating tube 21 can be made of any material having a high thermal conductivity, but brass, copper or the like can be preferably used. Further, the heating tube 21 may have an arbitrary cross-sectional shape, but it is preferable that the heating tube 21 has a rectangular shape because the contact area with the outer surface of the supply-side manifold 2 becomes large.

In this embodiment, the shape of the inside of the tube is 17.6 mm wide, 7.6 mm high,
Good results could be obtained by winding a rectangular brass tube 21 having a plate thickness of 1.2 mm around the supply side manifold 2 having an outer diameter of 30 mm at a pitch of 40 mm. The shape and material of the heating pipe 21,
The winding mode can be variously changed according to the required vaporization capacity of the vaporizer for both air temperature and hot water.

One end of the heating pipe 21, that is, an inlet end 22 is connected to a hot water storage tank 31 of a hot water supply source 30 via a supply line L ₁ equipped with a pump P, and the other end, that is, an outlet end 23 is returned. It is returned to the hot water supply source 30 via the pipe line L ₂ . Therefore, the hot water from the hot water storage tank 31 is supplied to the inlet 22 of the heating pipe 21 by the pump P via the supply pipe L ₁ , and then the inside of the heating pipe 21 is heat-exchanged with the LPG passing through the inside of the supply-side manifold 2. While flowing to the outlet 23, it is returned to the hot water storage tank via the return line L ₂ .

In this embodiment, the hot water storage tank 31 of the hot water supply source 30 is a hot water storage type hot water boiler, and a heating source such as a boiler (not shown).
Is attached. Therefore, from the heating pipe 21, the return line L ₂
The hot water that is returned to the hot water storage tank 31 via the temperature detecting means 32, such as a thermistor disposed at a proper position of the return line L ₂ , detects the temperature of the hot water, and is set in advance by the driver. The combustion of the boiler is controlled by the difference from the temperature, and hot water of a predetermined temperature, for example, hot water of about 60 ° C. to 80 ° C. is always supplied into the heating pipe 21. The amount of hot water supplied into the heating pipe 21 may be variously selected depending on the desired vaporization capacity of the air / hot water vaporizer.

Further, the hot water supply source 30 is provided with a level detector 33 such as a level oscillator in order to keep the water level of the hot water in the hot water storage tank 31 constant at all times, and the water supply line L is supplied by the signal from the level detector 33. _{By controlling the third} valve, that is, the pneumatic actuator valve 34, the amount of water supplied to the hot water storage tank 31 via the water supply line L ₃ is adjusted.

In the present invention, the liquid used as warm water may be ordinary water, but antifreeze mixed water in which an antifreeze is mixed is preferable. The reason is as follows.

That is, for example, when liquefied propane gas is used as the raw material LPG, the LPG pipe 2 of the vaporizer 1 for both air temperature and hot water
Liquefied propane gas at a low temperature close to -42 ° C will flow into 1. Therefore, for example, in the heating tube 21, for example 60 ℃ ~ 80
Even if warm water of about ℃ was flowed in at a flow rate of 0.2 to 0.4 / min, the inner side near the supply-side manifold 2 was -42 ℃.
Cooled due to LPG near and risk of freezing. In particular, as the center of the warm water flowing in the heating pipe 21 approaches the supply side manifold 2, the flow velocity decreases due to frictional resistance, and the inner surface of the supply side manifold 2 side becomes close to zero and becomes a static water state. There is a possibility that it will be further cooled and frozen. Therefore, in order to prevent freezing even if the inflow of warm water is stopped, the mixing of an antifreeze liquid is extremely preferable or in some cases essential.

Ethylene glycol as the main ingredient of antifreeze is 30 ~
Commercially available antifreeze containing 60% can be used. The amount of antifreeze will usually be water: antifreeze = 10: 2 to 3 although it varies depending on the conditions or region where the vaporizer is used. .

The operation of the air-heated / hot-water type vaporizer having the above structure will be described below.

For example, in the 13A propane air gas production plant that produces 13A propane air gas by mixing liquefied propane gas as a raw material and vaporized propane gas and air, the above-mentioned air temperature / hot water vaporizer 1 according to the present invention is used. When, for example, in the summer, when the atmospheric temperature is -8 ° C. or higher, it is cloudy, and there is no wind for 4 hours of continuous operation, the air-temperature / hot-water type vaporizer 1 has hot water circulated in the heating pipe 21. There is no. Therefore, the air-temperature / hot-water type vaporizer 1 merely functions as an air-temperature vaporizer. That is, liquefied propane gas (LPG) supplied to the vaporizer 1 for both air temperature and hot water
Flows from the supply-side manifold 2 to the discharge-side manifold 4 via the heat transfer tube 6. At this time, the liquefied propane gas is vaporized by the action of the heat transfer tube 6 and the heat transfer fins 8 to become propane gas (G).

On the other hand, when it is used in a severe cold season when the atmospheric temperature becomes lower than -8 ° C, or when it is used in a cold district, the warm water L of a predetermined temperature is supplied from the warm water storage tank 31 of the warm water supply source 30 to the circulation pump P.
Is fed by pressure into the heating pipe 21 wound around the supply-side manifold 2 via the supply pipe L ₁ .

Liquefied propane gas (LPG) is delivered to the supply-side manifold 2 and exchanges heat with hot water flowing in a heating pipe 21 wound around the outer surface of the supply-side manifold 2 and is thereby vaporized. It Evaporated propane gas (G)
Flows to the discharge side manifold 4 via the heat transfer tube 6. Therefore, in general, the liquefied propane gas is not vaporized in the heat transfer tube 6, but the supply side manifold 2
The liquefied propane gas that has not been vaporized therein is completely vaporized by the heat transfer tube 6.

At this time, according to the present invention, since the heating pipe 21 for flowing hot water is wound around the outer surface of the supply-side manifold 2, it escapes from the outer periphery of the heating pipe 21 into the atmosphere. The heat energy of the hot water is transferred to the heat transfer tube 6 located between the supply side manifold 2 and the discharge side manifold 4.
In addition, the heat transfer fins 8 are heated, so that the vaporization action of the liquefied propane gas by the heat transfer tubes 6 can be promoted.

The temperature of the hot water discharged from the outlet 23 of the heating pipe 21 and flowing into the hot water storage tank 31 is lowered by heat exchange with the liquefied propane gas, and therefore, for example, the hot water is arranged at a proper position in the return pipe line L _2. The temperature detecting means 32 detects the temperature of the hot water.
The hot water storage tank 31 is heated and controlled based on a signal from the temperature detecting means 32, and the water fed from the hot water storage tank 31 to the heating pipe 21 again is heated to a predetermined temperature.

Alternatively, when the hot water in the hot water storage tank 31 has its water level lowered due to evaporation or the like, the level detector 33 detects the drop in the water level, and the signal of the level detector 33 causes the valve 34 of the water supply line L ₃ to be turned on. It controls and supplies a predetermined amount of water to the warm water storage tank 31 through the water supply line L ₃ .

In the above description, the hot water heating of the supply side manifold 2 has been described as being used in a severe cold season when the atmospheric temperature is lower than -8 ° C, or in a cold region. For example, in the summer, the heat transfer tube 6 or When frost is formed on the heat transfer fins 8, hot water heating can be performed, which makes it possible to automatically remove such frost, and to remove frost, a preliminary vaporizer for switching. Is avoided.

More specifically, even in the summer, by causing warm water to flow through the heating pipe 21, the vaporization of liquefied propane gas flowing inside the supply-side manifold 2 is promoted, and the heat transfer tube 6
In addition to assisting the vaporization action of the heat transfer fins 8, as described above, the heat energy of the hot water that has escaped from the outer periphery of the heating pipe 21 to the atmosphere is fed between the supply-side manifold 2 and the discharge-side manifold 4. By providing the heat transfer tubes 6 and the heat transfer fins 8 located between them, the frost removal of the heat transfer tubes 6 and the heat transfer fins 8 can be effectively achieved.
Therefore, according to the present invention, the switching prevaporizer and the like conventionally prepared for use when the heat transfer tubes 6 and the heat transfer fins 8 are frosted are unnecessary.

Further, in the above description, the case where the air-temperature / hot-water dual-use vaporizer 1 configured according to the present invention is used in a 13A propane air gas production plant has been described. It can be suitably used for vaporizing other LPG, for example, liquefied butane.

In other words, liquefied butane used in a propane air gas plant has a high boiling point, that is, it is 15 ° C in the case of 1 kg / cm ² · G, and it was impossible to use the conventional air-temperature type forced vaporizer, The air-heated / hot-water type vaporizer 1 of the present invention can be preferably used, and vaporization of liquefied butane can be achieved extremely efficiently.

EFFECT OF THE INVENTION Air temperature provided with the air temperature / hot water type vaporizer according to the present invention
Since the LPG air gas production plant that also serves as hot water is configured as described above, (1) Air temperature type in summer, hot water type in winter, etc.
Switching operation is possible depending on climatic conditions, etc., and LPG can be suitably vaporized even in cold regions or in extremely cold seasons.

(2) The hot water heating increases the vaporization capacity and the evaporation capacity of the air-temperature vaporization device, and the hot water heating makes it possible to remove frost on the heat transfer tubes and the like, thus eliminating the need for a preliminary vaporizer for switching.

(3) Not only can it be effectively applied to the 13A propane air gas production plant, but it can also be used in the butane air gas production plant where the conventional air-temperature forced vaporizer could not be used, resulting in efficient LPG air gas production. Can be manufactured.

It has various benefits such as.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an air-temperature / hot-water type vaporizer that constitutes a main part of the present invention. FIG. 2 is a perspective view of the supply side manifold. 1: Air-heated / hot-water type vaporizer 2: Supply side manifold 4: Discharge side manifold 6: Heat transfer tube 8: Heat transfer fin 21: Heating tube 22: Jacket tube 30: Hot water supply source

Claims (3)

[Claims] 1. A liquefied petroleum gas, which is liquefied propane gas or liquefied butane gas, is vaporized by an air temperature / hot water vaporizer, and the vaporized liquefied petroleum gas is mixed with air to produce LPG.
A plant for producing air gas, wherein the air-heated / hot-water type vaporizer is connected to a supply-side manifold, a discharge-side manifold, one end to the supply-side manifold, and the other end to the discharge-side manifold. An air temperature / hot water dual-use type LPG air gas production plant comprising a plurality of heat transfer tubes and a heating tube wound around the outer periphery of the supply-side manifold and internally supplied with hot water. 2. The air temperature / hot water combined type LPG air gas manufacturing plant according to claim 1, wherein the heating pipe has a rectangular cross section. 3. The air temperature / hot water combined LPG air gas production plant according to claim 1, wherein the hot water is water mixed with an antifreeze liquid.