JP5105615B2 - Combustion gas supply method and pipeline for supplying the combustion gas - Google Patents

Description

  The present invention is a combustion gas containing an odorant supplied as a heat source to a general gas combustion device provided by a consumer, and a combustion containing no odorant supplied to a specific gas device such as a fuel cell. The present invention relates to a method for supplying gas using a pipeline, and a pipeline for supplying these two kinds of combustion gases.

  Fuel cells, which are specific gas equipment, have higher power generation efficiency than other power generation systems, and generate electrical energy through the reaction between hydrogen ions and oxygen, so that they do not generate substances that pollute the atmosphere. The spread to general households and passenger cars is progressing.

  Conventionally, it has been proposed to produce city gas by reforming city gas and use this hydrogen gas in a fuel cell. Technologies for reforming city gas and using it in fuel cells include, for example, technology that creates hydrogen gas by passing a mixture of city gas and water vapor through a catalyst, and a certain amount of city gas (hydrocarbon gas). After the hydrogen gas in the city gas is separated at one or more locations in the conduit network, at least a part of the separated city gas is supplied to the conduit network. By returning, a technology that uses both city gas equipment and a fuel cell that selectively uses only hydrogen gas has been proposed.

  A gas obtained by mixing a certain amount of hydrogen gas with the city gas is supplied through a conduit network, and the hydrogen gas in the city gas is separated at one or more locations of the conduit network, and the separated hydrogen gas is used as fuel. In the technology to supply batteries, there is an advantage that the existing city gas pipeline that supplies city gas can be used. However, consumers including general households have a separation device that separates hydrogen gas contained in city gas. It is necessary to install. For this reason, there is a problem that the introduction of the fuel cell system is expensive for the consumer.

  Instead of the above-described method of supplying city gas, which is a mixture of city gas and hydrogen gas, to a consumer, for example, city gas produced by a city gas production facility and hydrogen gas produced by a hydrogen gas production facility are separately provided. If a means for supplying to customers using a double pipe is adopted, a separation device for separating the hydrogen gas contained in the city gas is not required.

  Various techniques have been proposed in the past for supplying two different gases separately using a double pipe. For example, it is proposed by the invention described in the following patent document.

Patent Document 1 proposes a gas leakage detection device for supplying high-pressure gas from a gas supply device to a production facility using a gas supply tube having a double structure of an inner tube and an outer tube. In this gas leak detection device, high-pressure gas is sent to the production facility through the inner pipe of the double-structure gas supply pipe, and is inactive from the production equipment side between the inner and outer pipes of the dual-structure gas supply pipe. It is described that gas is sent out and gas leakage in the inner pipe is detected by a gas leak detection sensor. Patent Document 1 describes that the high-pressure gas is a gas used in a CVD or etching process, and the inert gas is N ₂ gas.

In Patent Document 2, the gas pipe of the fuel gas supplied to the marine boiler is a double pipe, the fuel gas is supplied to the inner pipe, and the inert gas is sealed in the outer pipe at a pressure higher than the gas pressure of the inner pipe. A gas leak detection system that detects the pressure of the inert gas and issues a warning when the detected value falls below a predetermined value has been proposed. Patent Document 2 describes that the inert gas is N ₂ gas.

  For the purpose of providing a highly safe fuel cell system, Patent Document 3 discloses a double-pipe structure in which hydrogen gas serving as a fuel gas is circulated in an inner pipe and an inert gas is circulated in an outer pipe. Proposed fuel cell systems have been proposed. Furthermore, Patent Document 3 discloses that a fuel gas detector for detecting hydrogen gas contained in an inert gas flowing through the outer pipe is provided, and that the inner pipe is made of resin.

  Patent Document 4 proposes a gas supply device for supplying hydrogen gas compressed to a high pressure (for example, 35 to 70 MPa) to a fuel cell vehicle. In this gas supply apparatus, it is described that a resin gas filling hose used for supplying hydrogen gas has a double structure. Furthermore, it is disclosed that this double-structure gas-filled hose allows hydrogen gas to flow through the internal hose, and the external hose is used to collect hydrogen gas that has permeated from the internal hose.

  Patent Document 5 proposes a gas conduit including a double pipe for pumping two kinds of gases having different pressures. And about the gas conduit which consists of this double pipe, the pressure of the gas pumped using an inner pipe is made higher than the pressure of the gas pumped using the space which an inner pipe and an outer pipe form. Has been.

JP-A-7-91600 JP 2002-54800 A JP 2006-286273 A JP 2007-92928 A JP 2006-125552 A

  The invention described in Patent Document 1 is intended to detect leakage of this high-pressure gas in a pipe for supplying high-pressure gas to a semiconductor manufacturing apparatus. In addition, in the double-structured pipe disclosed in Patent Document 1, a high-pressure gas supplied from a gas supply device is allowed to flow through the inner pipe, and an inert gas is allowed to flow between the outer pipe and the inner pipe. Is. Therefore, this double-structured pipe is not a means used for simultaneously flowing hydrogen gas and city gas used in the fuel cell.

  An object of the invention described in Patent Document 2 is to provide a highly reliable gas leak detection system using a gas pipe for fuel gas supplied to a marine boiler as a double pipe. The double-structured pipe disclosed in Patent Document 2 is a system in which a fuel gas flows in the inner pipe and an inert gas is sealed in the outer pipe at a higher pressure than the fuel gas flowing in the inner pipe. It is. Therefore, as in Patent Document 1, this double-structured pipe is not a means used for flowing hydrogen gas and city gas used in a fuel cell simultaneously.

  The invention described in Patent Document 3 describes that in a fuel cell system, hydrogen gas is allowed to flow in the inner pipe of a pipe having a double structure, and an inert gas is allowed to flow in the outer pipe. The use of this pipe as a means for simultaneously flowing hydrogen gas and city gas used in a fuel cell is not disclosed.

  The invention described in Patent Document 4 discloses a double-structure gas filling hose used to supply hydrogen gas compressed to a high pressure to a fuel cell vehicle. Similarly to Patent Documents 3 and 4 described above, use of hydrogen gas and city gas used in a fuel cell as a means for flowing simultaneously is not disclosed.

  By constructing a pipeline system that supplies city gas as a heat source and hydrogen gas used in a fuel cell to a consumer at the same time using a pipeline that supplies city gas, a fuel cell is provided to consumers including ordinary households. And further promotion of cogeneration.

  In the invention described in Patent Document 5, city gas having different pressures is supplied using a double pipe, and the pressure of the gas fed by using the inner pipe of the double pipe is changed between the inner pipe and the outer pipe. It is described that the pressure is higher than the pressure of the gas to be pumped using the space formed by and. Therefore, the double pipe disclosed in Patent Document 5 is a conduit for pumping two types of city gas having different pressures using the double pipe, and is attached to the city gas containing an odorant. It is not a conduit for supplying hydrogen gas for fuel cells without odorant.

  Accordingly, an object of the present invention is a combustion gas used for general gas combustion equipment, which contains a odorant such as city gas, and a combustion gas used for a specific gas equipment, for example, a fuel cell facility. To provide a combustion gas supply method for simultaneously supplying a combustion gas that does not contain an odorant, such as hydrogen gas, and a pipeline for supplying these two types of combustion gas .

In order to solve the above-described problem, the combustion gas supply method according to the first aspect of the present invention provides an odorant for a general gas combustion apparatus in which a consumer installs a combustion gas containing an odorant. A combustion gas supply method for supplying combustion gas not containing gas to a specific gas device installed by the consumer using a pipeline,
The pipeline includes a double pipe composed of an outer pipe and an inner pipe inserted into the outer pipe. In the double pipe, the combustion gas containing the odorant is supplied to the outer pipe and the inner pipe. It is made to flow into the space formed by piping, and the combustion gas which does not contain the said odorant is flowed in the said inside piping.

  Further, the invention according to claim 2 relates to the combustion gas supply method according to claim 1, and in the double pipe, the pressure of the combustion gas not containing the odorant flowing in the inner pipe ( P1) is made larger than the pressure (P2) of the combustion gas containing the odorant flowing through the space.

Furthermore, the pipeline for supplying the combustion gas according to the invention of claim 3 contains the odorant in the general gas combustion equipment in which the consumer installs the combustion gas containing the odorant. A pipeline for supplying specific gas equipment installed by consumers with no combustion gas,
The pipeline includes a double pipe portion composed of a double pipe having an outer pipe and an inner pipe inserted into the outer pipe,
The double pipe section is a pipe for flowing the combustion gas not containing the odorant in the inner pipe, and a space formed by the outer pipe and the inner pipe is further formed in the odorant. It has a piping structure for flowing in the combustion gas.
The pipeline uses the pressure (P1) of the combustion gas that does not contain the odorant flowing in the inner pipe of the double pipe part, and the pressure of the combustion gas that contains the odorant that flows through the space part. (P2) It is characterized by having pressure adjusting means for flowing larger.

  The invention according to claim 4 relates to the pipeline for supplying combustion gas according to claim 3, wherein the outer pipe constituting the double pipe section is a combustion containing the odorant. It is an existing pipe that supplies gas.

The combustion gas containing the odorant described above indicates a combustion gas used as a heat source such as city gas. Furthermore, the above-described combustion gas containing no odorant means a combustion (fuel) gas that is supplied to a fuel cell such as hydrogen gas and used for power generation.
The above-mentioned general gas combustion equipment refers to gas combustion equipment using the above-mentioned city gas or the like as a heat source, and examples thereof include a hot water supply device (water heater), a gas stove, a gas stove, and the like. Furthermore, the above-described specific gas device refers to a fuel cell (fuel cell facility).

The present invention can exhibit the following effects.
(1) Even if hydrogen gas that does not contain odorant flows through the inner pipe of the double pipe and leaks from the inner pipe, the leaked hydrogen gas is the pressure of the hydrogen gas flowing through the double pipe (P1) And the pressure of the city gas (P2) flows into the space formed by the outer pipe and the inner pipe. Further, since there is an outer pipe through which city gas containing odorant flows outside the inner pipe, hydrogen gas leaked from the inner pipe can be prevented from leaking to the outside through the outer pipe. Also, in the unlikely event that gas leaks from the outer pipe, it is possible to detect city gas leaks from the odors of odorants added to city gas, and hydrogen gas leaks have occurred. It becomes possible to predict that there is a possibility.

  (2) In the conventional fuel cell system, even if the heat (waste heat) generated from the fuel cell is used effectively to cover hot water supply or other heat demand in a house, etc., this waste heat alone is insufficient as the amount of heat. There was a possibility. Although hydrogen has a low calorific value and is disadvantageous for generating heat, the present invention supplies a high calorific value of city gas as a heat source and hydrogen gas used for a fuel cell simultaneously to a consumer such as a house. Therefore, power generation is mainly carried out by fuel cells using hydrogen gas, and for heat demand, effective use of waste heat generated by power generation by fuel cells and cogeneration corresponding to the combustion heat of city gas are constructed. It becomes possible.

  (3) In the double pipe, the hydrogen gas supply pressure (P1) flowing in the inner pipe is made higher than the city gas supply pressure (P2) flowing in the space formed by the outer pipe and the inner pipe. Therefore, even if hydrogen gas leaks into the inner pipe, the city gas does not flow into the inner pipe and the composition of the hydrogen gas does not change. As a result, the odorant contained in the city gas can be prevented from flowing into the hydrogen gas flowing in the inner pipe, so that the adverse effect of the odorant on the fuel cell of the fuel cell facility is prevented. Will be able to.

  (4) Since it is possible to construct a pipeline for supplying hydrogen gas inside an existing pipeline for supplying city gas, city gas and fuel are utilized using the existing pipeline for supplying city gas. It is possible to build a social infrastructure that supplies hydrogen gas used in batteries at the same time. In addition, it is possible to construct a pipeline as a hydrogen supply infrastructure for supplying hydrogen gas without requiring large-scale construction such as road excavation.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining an example of laying a pipeline for carrying out the present invention, in which a combustion gas containing an odorant and a combustion gas not containing an odorant are produced. The pipeline laid in order to supply from the apparatus to the consumer who lives in the apartment house A is shown.

  In the following description, the combustion gas containing the odorant is described as “city gas” and the combustion gas not containing the odorant is described as “hydrogen gas”. Moreover, although the above-mentioned consumer shows the example of the consumer who lives in the apartment house A in FIG. 1, in this invention, the consumer who lives in a detached house, various commercial and service facilities , Various manufacturing factories, various educational institutions, etc.

In FIG. 1, 1 is a city gas production apparatus installed in a city gas production plant. The city gas produced by the city gas production device 1 is temporarily stored in the city gas storage device 2. In addition, the city gas manufactured with the city gas manufacturing apparatus 1 shows the gas whose combustion specification is 13A currently widely supplied to the consumer from the gas company, for example. This 13A gas is mainly composed of methane (CH ₄ ) and contains ethane (C ₂ H ₂ ), propane (C ₃ H ₈ ), and the like. The city gas production apparatus 1 mixes (adds) an odorant to 13A gas obtained by vaporizing liquefied natural gas (LPG) and further adding a gas for increasing the calorific value. The 13A gas containing the odorant is stored in the city gas storage device 2. As this odorant, a sulfur compound, for example, dimethyl sulfite, which has a special bad odor for humans when gas leakage occurs, is used.

  The city gas stored in the city gas storage device 2 has a predetermined pressure, for example, an intermediate pressure A (0.3 to 1 MPa) or an intermediate pressure B (0.1 to 0.3 MPa) by pressure adjusting means such as a governor. And is supplied to the intermediate pressure conduit 3. The intermediate pressure conduit 3 is provided with a branch portion F0, and the low pressure conduit 4 is branched from the branch portion F0. The low-pressure conduit 4 is provided with a governor G1 for adjusting the pressure of the city gas having the medium pressure A or medium pressure B branched from the medium-pressure conduit 3 to a low pressure (about 2.5 KPa). As a result, the pressure of the city gas flowing in the low pressure conduit 4 is adjusted to about 2.5 KPa by the governor G1 serving as the pressure adjusting means. The medium pressure conduit 3 and the low pressure conduit 4 are made of steel pipes, resin-coated steel pipes, or synthetic resin pipes such as polyethylene pipes.

  5 is a hydrogen gas production apparatus. The hydrogen gas produced by the hydrogen gas production device 5 is temporarily stored in the hydrogen gas storage device 6. The hydrogen gas stored in the hydrogen gas storage device 6 is adjusted to a predetermined pressure, for example, an intermediate pressure B (0.1 to 0.3 MPa) by the governor G2, and is guided to the hydrogen gas conduit 7. The material of the hydrogen gas conduit 7 is a steel pipe, a resin-coated steel pipe, or a synthetic resin pipe such as a polyethylene pipe. In addition, the method of manufacturing hydrogen gas in the hydrogen gas manufacturing apparatus 5 can manufacture conventionally fuel gas, such as methanol and methane, by the modification | reformation using water vapor | steam.

  A low-pressure conduit 4 for supplying city gas and a hydrogen gas conduit 7 for supplying hydrogen gas are connected to a double pipe 8 at a junction F1 shown in FIG. The double pipe 8 is a collective housing in which the city gas, which is a combustion gas to which odorant is added (entered), and the hydrogen gas, which is a combustion gas that does not contain an odorant, are separated separately. This is a pipeline for supplying general gas combustion equipment and specific gas equipment installed by consumers a1, a2, a3, etc. living in A. Therefore, the pipeline that supplies the city gas containing the odorant and the hydrogen gas not containing the odorant has a portion (double piping portion) provided with the double piping 8.

  In addition, the general gas combustion apparatus mentioned above is the hot water supply apparatus 15, the gas stove 16, the gas heating apparatus, etc. which use city gas as a heat source, as shown in FIG. The specific gas equipment is a fuel cell (fuel cell facility) 13 for generating power using hydrogen gas.

  The double pipe 8 shown in FIG. 1 is a straight pipe (straight pipe), but may be a pipe bent at a predetermined angle from the end of the straight pipe. Moreover, most of the double pipe 8 is buried underground. In addition, although the total extension of the double piping 8 is based on the position of the confluence | merging part F1 and the apartment house A, generally it is several hundred-several thousand m.

  2 and 3 show the cross-sectional shape of the double pipe 8. As shown in FIGS. 2 and 3, the double pipe 8 is composed of a double pipe including an outer pipe 8a and an inner pipe 8b inserted into the outer pipe 8a. Further, when the inner pipe 8b having an outer diameter smaller than the inner diameter of the outer pipe 8a is inserted into the outer pipe 8a, the double pipe 8 has an inner peripheral surface of the outer pipe 8a and an outer peripheral surface of the inner pipe 8b. The space 8c is formed between the two. The material of the outer pipe 8a is a steel pipe, a resin-coated steel pipe, or a polyethylene pipe that has been conventionally used as a piping member for city gas. The inner pipe 8b uses a polyethylene pipe.

  In the present embodiment, the city gas is guided to the space 8c formed by the inner peripheral surface of the outer pipe 8a and the outer peripheral surface of the inner pipe 8b constituting the double pipe 8 at the junction F1, and further, hydrogen gas Is introduced into the inner pipe 8b constituting the double pipe 8, and the city gas and hydrogen gas are individually supplied to the apartment house A as a consumer or to the vicinity of the apartment house A. That is, according to the present invention, the city gas and hydrogen gas are supplied to the consumer in the double pipe (double pipe section) 8 of the pipeline so that the city gas and the hydrogen gas flow separately. There are features.

  Further, when the pressure (supply pressure) of hydrogen gas flowing in the inner pipe 8b constituting the double pipe 8 is P1, and the pressure (supply pressure) of city gas flowing in the space 8c is P2, the pressure (P1) It is also a feature of the present invention that the gas pressure is set so that> pressure (P2).

  In the present invention, the outer pipe 8a constituting the double pipe 8 uses an existing pipe (steel pipe, resin-coated steel pipe, polyethylene pipe, etc.) laid on the ground or the like to supply city gas. You can also

  In the present embodiment, when the pressure of the hydrogen gas flowing individually in the double pipe 8 is P1, and the pressure of the city gas is P2, in order to satisfy the pressure (P1)> pressure (P2), The following means can be employed. That is, the city gas stored in the city gas storage device 2 is subjected to a predetermined pressure, for example, an intermediate pressure A (0.3 to 1 MPa), or an intermediate pressure B (0.1 to 0.00) by a pressure adjusting means such as a governor. 3 MPa) and supplied to the medium pressure conduit 3. Further, the city gas flowing in the low pressure conduit 4 branched from the intermediate pressure conduit 3 is adjusted to a low pressure (about 2.5 KPa) by the governor G1. On the other hand, the hydrogen gas stored in the hydrogen gas storage device 6 is adjusted to a predetermined pressure, for example, an intermediate pressure B (0.1 to 0.3 MPa) by the governor G2, and led to the hydrogen gas conduit 7. And as shown in FIG. 1, the low voltage | pressure conduit | pipe 4 and the hydrogen gas conduit | pipe 7 are each connected to the double piping 8 in the junction part F1. In this junction F1, the city gas flowing in the low pressure conduit 4 is supplied to the space 8c of the double pipe 8, and the hydrogen gas flowing in the hydrogen gas conduit 7 is supplied to the inner pipe 8b of the double pipe 8. To do.

  Therefore, in the junction F1 of the double pipe 8, the pressure P1 of the hydrogen gas supplied to the inner pipe 8b becomes an intermediate pressure B (0.1 to 0.3 MPa) and is formed by the outer pipe 8a and the inner pipe 8b. The pressure P2 of the city gas supplied to the space 8c is a low pressure (about 2.5 KPa). As a result, pressure loss occurs when the hydrogen gas and city gas supplied to the specific gas equipment and the general gas combustion equipment of the customer individually through the double pipe 8 flow in the double pipe 8. Even so, it is possible to flow through the double pipe 8 while maintaining the relationship of “pressure (P1)> pressure (P2)”.

  As described above, when the pressure (P1) of the hydrogen gas that is the two kinds of combustion gas flowing in the double pipe 8 and the pressure (P2) of the city gas are set such that pressure (P1)> pressure (P2), An effect is produced.

  (1) Even if hydrogen gas that does not contain an odorant leaks through the inner pipe 8b of the double pipe 8, the leaked hydrogen gas is the pressure between the pressure (P1) and the pressure (P2). Due to the difference, the air flows into the space 8c formed by the outer pipe 8a and the inner pipe 8b. Further, since the outer pipe 8a through which the city gas containing the odorant flows is present outside the inner pipe 8b, the outer pipe 8a can prevent hydrogen gas from leaking to the outside. In the unlikely event that gas leaks from the outer pipe 8a, it is possible to detect the leak of city gas from the odor of the odorant added to the city gas, and further, hydrogen gas leaks. It will be possible to predict that there is a possibility.

  (2) In the double pipe 8, the pressure P1 of the hydrogen gas flowing in the inner pipe 8b is higher than the pressure P2 of the city gas flowing in the space 8c formed by the outer pipe 8a and the inner pipe 8b. Even if hydrogen gas leaks into the inner pipe 8b, the city gas does not flow into the inner pipe 8b and the composition of the hydrogen gas does not change. As a result, the odorant contained in the city gas can be prevented from flowing into the hydrogen gas flowing in the inner pipe 8b, so that the adverse effect of the odorant on the fuel cell of the fuel cell facility 13 is prevented. Will be able to.

  In order to supply the city gas and hydrogen gas to the consumer at the same time by providing the double pipe 8 in the pipeline, the low-pressure pipe 4 for supplying the city gas is connected to the space of the double pipe 8 at the junction F1 described above. A connection structure for connecting the inside of the hydrogen gas conduit 7 for supplying hydrogen gas to the portion 8c to the inner pipe 8b of the double pipe 8, that is, a joint structure is important. This is because it is necessary to have a joint structure in which no leakage of city gas or hydrogen gas occurs from this junction F1.

  Then, an example of the joint structure in the junction part F1 is demonstrated. FIG. 4 is a cross-sectional view showing an example of a joint structure when the outer pipe 8a and the inner pipe 8b constituting the low-pressure pipe 4, the hydrogen gas pipe 7, and the double pipe 8 all use polyethylene pipes. In the joint structure shown in FIG. 4, the example using the joint 20 and the joint 30 is shown. As the joint 20 and the joint 30, heat fusion joints (electrofusion joints) for polyethylene pipes (hereinafter referred to as “EF joints”) that have been widely used can be used.

  As the EF joint 20 shown in FIG. 4, a T (tees) type or branch pipe take-out type joint can be used. As shown in FIG. 4, the EF joint 20 includes an insertion port 21 having a cylindrical opening for inserting the outer pipe 8 a of the double pipe 8 and a cylinder for inserting the inner pipe 8 b of the double pipe 8. An insertion port 22 having a cylindrical opening and an insertion port 23 having a cylindrical opening for inserting the low-pressure conduit 4 are provided.

  The insertion port 21 of the EF joint 20 serves as an insertion port for fixing the outer piping 8a of the double piping 8 inserted into the insertion port 21 to the insertion port 21 by heat fusion. Similarly, the insertion port 22 becomes an insertion port for fixing the inner piping 8b of the double piping 8 inserted into the insertion port 22 to the insertion port 22 by heat fusion. The insertion port 23 serves as an insertion port for fixing the low-pressure conduit 4 inserted into the insertion port 23 to the insertion port 23 by heat fusion.

  The diameter of the insertion port 21 provided in the EF joint 20 is substantially the same as the outer diameter of the outer pipe 8a of the double pipe 8, and the diameter of the insertion port 22 is the outer diameter of the inner pipe 8b of the double pipe 8. The diameter of the insertion port 23 is substantially the same as the outer diameter of the low-pressure conduit 4. In addition, heating wires 24a, 24b, and 24c are embedded at positions that are slightly spaced from the inner peripheral surfaces of the insertion ports 21, 22, and 23.

  The EF joint 30 shown in FIG. 4 is a socket-type joint, and inserts the insertion port 31 having a cylindrical opening for inserting the hydrogen gas conduit 7 and the end of the inner pipe 8b of the double pipe 8. An insertion port 32 having a cylindrical opening is provided. The insertion port 31 serves as an insertion port for fixing the hydrogen gas conduit 7 inserted into the insertion port 31 to the insertion port 31 by heat fusion. Similarly, the insertion port 32 becomes an insertion port for fixing the inner piping 8b of the double piping 8 inserted into the insertion port 32 to the insertion port 32 by heat fusion. The diameters of the insertion ports 31 and 32 are substantially the same as the outer diameter of the hydrogen gas conduit 7 and the outer diameter of the inner pipe 8b, respectively. In addition, heating wires 33a and 33b are embedded at positions slightly spaced from the inner peripheral surfaces of the insertion ports 31 and 32, respectively.

  Subsequently, a procedure (construction method) for connecting the low-pressure conduit 4 to the outer piping 8a of the double piping 8 and the hydrogen gas conduit 7 to the inner piping 8b of the double piping 8 by the EF joints 20 and 30 at the junction F1. ) Will be described with reference to FIG. 4 as described in the following (Procedure 1) to (Procedure 7).

(Procedure 1)
First, the inner pipe 8 b is inserted into the outer pipe 8 a of the double pipe 8. At this time, the inner pipe 8b is made longer than the outer pipe 8a by a predetermined length. As described above, the double pipe 8 is not necessarily a straight pipe. For example, if necessary, the outer pipe 8a that is a straight pipe in units of several tens of meters to several hundreds of meters is temporarily cut to form the inner pipe. 7b is inserted. Then, the inner pipe 8b is inserted into the cut outer pipe 8a, and the adjacent inner pipes 8b are connected by socket type EF joints, and the adjacent outer pipes 8a are also connected by socket type EF joint EF joints. To do. In this procedure 1, when an existing city gas pipe is used as the outer pipe 8a, there is an effect that the work of excavating the ground entirely along the outer pipe 8a buried underground is unnecessary.

(Procedure 2)
The outer pipe 8a of the double pipe 8 is inserted into the insertion port 21 of the EF joint 20, and the inner pipe 8b inserted into the double pipe 8 is further extended from the end of the insertion port 22 of the EF joint 20 to a predetermined length. Protrude so much.

(Procedure 3)
A hole 25 having a predetermined diameter is drilled in the outer pipe 8a of the double pipe 8 inserted into the insertion port 21 of the EF joint 20 using a drilling tool. The position of the hole 25 is set to be directly below the insertion port 23 of the EF joint 20. The hole 25 can be drilled by inserting a blade of a drilling tool from the insertion port 23 of the EF joint 20. In this drilling operation, the hole 25 is drilled in a state in which the end of the outer pipe 8 a of the double pipe 8 is in contact with the protruding portion 26 formed at the back of the insertion port 21 of the EF joint 20.

(Procedure 4)
Subsequently, a predetermined voltage and current are applied to the heating wires 24a and 24b of the EF joint 20 and applied to an electrode (not shown in FIG. 4) provided on the outer surface of the EF joint 20 for a predetermined time. , 24b is heated. As a result, the inner peripheral surface of the insertion port 21 of the EF joint 20 made of polyethylene is thermally melted and fused integrally with the outer peripheral surface of the outer pipe 8 a of the double pipe 8. Further, the inner peripheral surface of the insertion port 22 of the EF joint 20 is also thermally melted and fused integrally with the outer peripheral surface of the inner pipe 8 b of the double pipe 8. Thereby, when the heat melting part cools, the outer pipe 8a and the inner pipe 8b of the double pipe 8 can be joined (connected) firmly and airtightly by the EF joint 20.

(Procedure 5)
Subsequently, the hydrogen gas conduit 7 is inserted into the insertion port 31 of the EF joint 30. Next, the end portion of the inner pipe 8 b that is protruded from the insertion port 22 of the EF joint 20 in (Procedure 2) is inserted into the insertion port 32 of the EF joint 30.

(Procedure 6)
Subsequently, a predetermined voltage and current are applied to the heating wires 33a and 33b embedded in the EF joint 30 for a predetermined time. Accordingly, the inner peripheral surface of the insertion port 31 of the EF joint 30 is the outer peripheral surface of the hydrogen gas conduit 7, and the inner peripheral surface of the insertion port 32 of the EF joint 30 is the outer peripheral surface of the inner pipe 8 b of the double pipe 8. It is possible to join (connect) firmly and airtightly by melting.

(Procedure 7)
Subsequently, the low pressure conduit 4 is inserted into the insertion port 23 of the EF joint 20, and a predetermined voltage and current are applied to the heating wire 24c for a predetermined time. Accordingly, the outer peripheral surface of the low-pressure conduit 4 can be firmly and airtightly joined to the insertion port 23 in the same manner as described above.

  By the above (Procedure 1) to (Procedure 7), the low-pressure conduit 4 through which the city gas flows is integrated with the insertion port 23 of the EF joint, and the hydrogen gas conduit 7 through which the hydrogen gas flows is integrated with the inner piping 8b of the double piping 8. While being connected, the outer peripheral surface of the outer pipe 8 a constituting the double pipe 8 can be connected to the insertion port 21 of the EF joint 20.

  Thereby, in the junction part F1 shown in FIG. 1, the city gas supplied from the city gas storage device 2 through the intermediate pressure conduit 3 and the low pressure conduit 4 is supplied with the outer piping 8a and the inner piping 8b constituting the double piping 8. Thus, it is possible to supply the space 8c formed by the above process while maintaining airtightness. Similarly, the hydrogen gas supplied from the hydrogen gas storage device 6 through the hydrogen gas conduit 7 can be supplied while maintaining airtightness in the inner pipe 8 b constituting the double pipe 8.

  About the joint structure of the above-mentioned confluence | merging part F1, although the example was demonstrated using EF joints 20 and 30, when the outer side piping 8a which comprises the double piping 8 is a steel pipe or a resin-coated steel pipe, EF joint 20 is Since it cannot be used, the low-pressure conduit 4 and the outer pipe 8a of the double pipe 8 are connected using a saddle-type joint or the like that has been conventionally used. Further, when a steel pipe or a resin-coated steel pipe is used as the hydrogen gas conduit 7, the connection between the hydrogen gas conduit 7 and the inner pipe 8b of the double pipe 8 is also connected using a saddle type joint or the like.

  In (Procedure 1) to (Procedure 7) described above, the low-pressure conduit 4 and the hydrogen gas conduit 7 are connected to the double pipe 8 at the junction F1 set at one end of the double pipe 8. However, the low-pressure conduit 4 or the hydrogen gas conduit 7 may be connected to the double pipe 8 using an appropriate joint including a saddle-type joint or the like.

  In the example of pipeline construction shown in FIG. 1, in consideration of safety against gas leakage, another double pipe 9 is connected to the double pipe 8 which is mainly buried underground and is resident in the apartment house A. It is desirable to extend the double pipe to the vicinity of the fuel cell facility 13 installed by the consumers a1, a2,. Further, the extended double pipe 9 is laid to the vicinity of the fuel cell equipment 13 of the consumers a1, a2,..., And is provided with branch portions F2, F3. The double pipe 10 is connected. As for the joint structure constituting the branch portions F2 and F3, when the outer pipe and the inner pipe of the double pipe 9 are polyethylene pipes, the double pipe 10 is connected to the outer pipe and the inner pipe of the double pipe 9. An EF joint having an appropriate structure for branching can be used.

  Further, among the double pipes 10 laid near the fuel cell facility 13, the inner pipe 10 b through which hydrogen gas flows is connected to the fuel cell facility 13, and the outer pipe 10 a and the inner pipe 10 b of the double pipe 10 are formed. In order to supply the city gas flowing through the space portion to the hot water supply device 15, the gas stove 16, etc., it is necessary to provide the branch portion F 4 in the double pipe 10.

  Hereinafter, the branch structure of the branch part F4 shown in FIG. 1 will be described. FIG. 5 is a cross-sectional view showing an example of the branch structure (joint structure) for the branch portion F4. The outer pipe 10a and the inner pipe 10b of the double pipe 10 are made of polyethylene pipes, and the EF joints 40 and 50 are connected to each other. The case where it was used is shown.

  The E7 joint 40 shown in FIG. 5 is a T (tees) -type or branch pipe take-out type joint similar to the EF joint 20 shown in FIG. 4, and the outer pipe 10a of the double pipe 10 is inserted and heat-sealed. Insertion port 41 for insertion, insertion port 42 for inserting and heat-sealing the inner pipe 10b of the double pipe 10, and city gas pipe 12 made of polyethylene for taking out the city gas flowing through the double pipe 10 The outlet 43 for heat-sealing is provided. In addition, heating wires 44 a, 44 b, 44 c are embedded at positions slightly spaced from the inner peripheral surfaces of the insertion ports 41, 42 and the outlet 43.

  The EF joint 50 shown in FIG. 5 is a socket type like the EF joint 30 shown in FIG. 4, and the hydrogen gas pipe 14 for supplying hydrogen gas to the inner pipe 10 b of the double pipe 10 and the fuel cell equipment 13. It is a joint for connecting. The EF joint 50 has an insertion port 51 for connecting the insertion port 51 for inserting the inner piping 10b of the double piping 10 and the hydrogen gas piping 14 for supplying hydrogen gas to the fuel cell facility 10. In addition, heating wires 53a and 53b are embedded at positions slightly spaced from the inner peripheral surfaces of the insertion ports 51 and 52.

  The method of strongly joining the outer pipe 10a of the double pipe 10, the outer peripheral surface of the inner pipe 10b, and the city gas pipe 12 to the EF joint 40 constituting the branch part F4 by heat fusion is as follows. A method similar to that of the EF joint 20 described above can be employed. Moreover, the method similar to the above-mentioned EF joint 30 can also be used for the method of connecting the inner pipe 10b of the double pipe 10 and the hydrogen gas pipe 14 to the EF joint 50.

  As shown in FIG. 5, the city gas pipe 12 connected to the outlet 43 of the EF joint 40 is connected to a city gas meter 60 installed in the consumers a1, a2,. Further, the city gas meter 60 is connected to the hot water supply device 15, the gas stove 16, the gas heating device, and the like, which are general gas combustion devices provided by consumers, by other piping. As a result, the city gas flowing through the space between the outer pipe 10a and the inner pipe 10b of the double pipe 10 can be supplied to these general gas combustion devices.

On the other hand, the hydrogen gas pipe 14 connected to the EF joint 50 is connected to a hydrogen gas meter 61. Further, a consumer is provided from the hydrogen gas meter 61 via another hydrogen gas pipe and connected to the fuel cell facility 13. Thereby, the hydrogen gas flowing in the inner pipe 10 b of the double pipe 10 can be supplied to the fuel cell facility 13.
Moreover, since heat is generated when power is generated using hydrogen gas in the fuel cell facility 13, this waste heat is supplied to, for example, the hot water supply device 15 via a pipe so that the waste heat is effectively used. Moreover, the electric power generated by the fuel cell facility 13 is used as a power source for a lighting device 18 such as a fluorescent lamp, a television receiver, etc. provided by a consumer via a power line 17.

  Although FIG. 1 shows an example in which the double pipes 8, 9, 10 are laid to the vicinity of the fuel cell facility 13 installed in the apartment house A, the following means may be adopted. The double pipe 8 is laid down to the underground near the apartment house A or to the central pipe unit room installed in the apartment house A. From here, for example, by using an appropriate joint as shown in FIG. 5, the city gas and hydrogen gas flowing through the double pipe 8 are branched into separate pipes, to each consumer in the apartment house A. Supply.

  Subsequently, for the inner pipes 8b, 10b, etc. for supplying hydrogen gas to the apartment house A shown in FIG. The calculated result will be described. The calculation conditions set to perform this calculation are as follows.

(Calculation condition)
a. Number of units in apartment house A: 80 b. Specification of fuel cell equipment: 1KW class pure hydrogen drive type fuel cell system (installed in each house)
c. Pure hydrogen consumption per unit: 0.7 Nm ³ / hour d. Fuel cell facility operation rate: 50%
(Hydrogen supply flow rate)
Based on the calculation conditions described above, the hydrogen gas supply amount to be supplied to the apartment house A is determined as follows.
80 × 0.7 × 0.5 = 28 Nm ³ / hour

Subsequently, based on the hydrogen supply amount obtained above, a hydrogen storage device (hydrogen station)
When the distance (transport distance) from the apartment house A to 30m, 100m, 500m, 3000m is calculated by calculating the inner pipe diameter (required pipe inner diameter) constituting the double pipes 8, 9, 10 It came to show in the column of 6 required piping internal diameters. In this calculation, the supply pressure of hydrogen gas supplied to the inner pipe of the double pipe was set to an intermediate pressure B (0.1 MPa to 0.3 MPa).

  As shown in FIG. 6, the required inner diameter of the inner pipe in the double pipe is 0.48 mm at a transport distance of 30 m, 1.56 mm at a transport distance of 100 m, 7.97 mm at a transport distance of 500 m, and 47.8 mm at a transport distance of 3000 m. The calculation result of was obtained. From this calculation result, it was found that the inner pipe of the double pipe can be supplied with the standard pipe 50A (inner diameter 48.2 mm) shown in FIG. 6 until the hydrogen gas mailing distance is 3000 m.

  In FIG. 1 showing the above-described embodiment of the present invention, the city gas production apparatus 1 for producing city gas and the hydrogen gas production apparatus 5 for producing hydrogen gas use city gas and hydrogen gas respectively using different gases. Although the example which manufactures is demonstrated, hydrogen gas can be manufactured using a means as shown in FIG. That is, the city gas is led from the intermediate pressure conduit 3 for supplying the city gas to the hydrogen production apparatus 5a. Then, the hydrogen gas production device 5 a produces hydrogen gas by the city gas reforming process, and stores the produced hydrogen gas in the hydrogen gas storage device 6. The hydrogen gas stored in the hydrogen gas storage device 6 is adjusted to an intermediate pressure B (0.1 to 0.3 MPa) by the ganaba G2 and led to the double pipe 8. On the other hand, the city gas flowing through the medium-pressure conduit 3 is branched by the low-pressure conduit 4, and the pressure is adjusted to a low pressure (2.5 KPa) by the governor G 1 so as to be led to the double pipe 8.

  In the pipeline shown in FIG. 7, when hydrogen gas produced by the reforming process of city gas is guided to the double pipe 8 constituting the pipeline, the hydrogen production apparatus 5a can be installed in a distributed manner. The effect of becoming.

  In the present invention, as described above, the pressure (P1) of the hydrogen gas flowing in the inner pipe of the double pipe 8 (9, 10) is formed by the outer pipe and the inner pipe of the double pipe. The pressure is greater than the pressure (P2) of city gas flowing through the space. In order to maintain the relationship between the pressures (P1) and (P2) with higher accuracy, the following means may be further employed.

  For example, as shown in FIG. 8, pressure adjusting means (governor) G3 and G4 for adjusting the pressures of city gas and hydrogen gas flowing individually in the double pipe 8 are provided at the important points of the double pipe 8, respectively. Provide. FIG. 8 shows an example in which a governor G3 for adjusting the pressure of hydrogen gas flowing in the inner pipe 8b of the double pipe 8 and a governor G4 for adjusting the pressure of city gas flowing in the double pipe 8 are installed. Is shown. In particular, when the pressure of the hydrogen gas supplied to the inner pipe 8b of the double pipe 8 is set to an intermediate pressure A (0.3 MPa to 1 MPa), a governor G3 for adjusting the hydrogen gas pressure is provided at one place or When the hydrogen gas is installed at several places and hydrogen gas is supplied to the consumer, the pressure is adjusted so that the intermediate pressure B is 0.1 MPa, for example. The number and location of the governors G3 and G4 may be set appropriately in consideration of the laying distance of the double pipe 8, the supply pressure and supply amount of city gas and hydrogen gas, and the like.

  The hydrogen gas and the city gas flowing in the double pipe 8 are individually led to the hydrogen gas governor G3 and the city gas governor G4, and the pressure-adjusted gases are returned to the double pipe 8 again. As the means, the EF joint 20 (40), the EF joint 30 (50), the branch pipe take-out joint, or the like shown in FIG. 4 or FIG. 5 is used.

  As described above, the outer pipe 8a of the double pipe 8 employed in the present invention can employ an existing polyethylene pipe for supplying city gas, a steel pipe, or a resin-coated steel pipe. The existing outer pipe 8a is mainly buried underground. Therefore, the operation of inserting the inner pipe 8b for supplying hydrogen gas to the outer pipe 8a buried underground is excavating the road or the like in which the outer pipe 8a is buried along the outer pipe 8a. Without making it possible, the following method will be established and implemented. That is, both ends of the outer pipe 8a that is a straight pipe are cut at a predetermined length, for example, the outer pipe 8a having a length of 500 m. Then, an inner pipe 8b made of a polyethylene pipe is inserted into the cut outer pipe 8a. Next, the inner pipe 8b inserted into the outer pipe 8a positioned adjacent to each other is connected, and further, the outer pipe 8a positioned adjacent to each other is connected. Thereby, the existing city gas piping can be used effectively.

In the above-described embodiment of the present invention, the case where the city gas and the hydrogen gas are simultaneously supplied to the apartment house A has been described. However, the city gas and the hydrogen gas can be simultaneously supplied to the detached house by the same method. Also, it is preferable to lay a dedicated double pipe 8 for a manufacturing plant that is a large-scale consumer who is expected to use a large amount of city gas and hydrogen gas.
Furthermore, it is possible to supply hydrogen gas to a hydrogen gas stand that supplies hydrogen gas for a fuel cell vehicle using the double pipe 8 employed in the present invention.

  Moreover, the diameter of the existing polyethylene pipe that supplies city gas or a steel pipe or the like becomes smaller as it approaches the customer from the main pipeline. Accordingly, the diameter of the hydrogen gas pipe (inner pipe) for supplying hydrogen gas to be inserted into the pipeline for supplying city gas should be reduced as it approaches the consumer using a socket type EF joint with a different diameter. To.

In order to implement this invention, it is a figure for demonstrating the structural example of the pipeline for supplying city gas and hydrogen gas to the consumer of the apartment house A from these gas manufacturing apparatuses. It is a longitudinal cross-sectional view which shows the structure of the double piping shown in FIG. It is a cross-sectional view which shows the structure of the double piping shown in FIG. In the double pipe shown in FIG. 1, it is sectional drawing for demonstrating the connection structure in the junction part F1. In the double pipe shown in FIG. 1, it is sectional drawing for demonstrating the branch structure in the branch part F4. It is a figure which shows the result calculated | required by calculation about the required piping internal diameter requested | required of the inner side piping which comprises double piping. It is a figure for demonstrating the other structural example about the pipeline for implementing this invention. It is a figure for demonstrating the further another structural example about the pipeline for implementing this invention.

Explanation of symbols

1: City gas production device 2: City gas storage device 3: Medium pressure conduit 4: Low pressure conduit 5: Hydrogen gas production device 6: Hydrogen gas storage device 7: Hydrogen gas conduit 8.9, 10: Double piping 12: City Gas piping 13: Fuel cell (fuel cell equipment)
15: Hot water supply device 17: Power line 18: Lighting equipment A: Apartment house F0, F2, F3, F4: Branch part F1: Junction part G1, G2, G3, G4: Governor (pressure adjusting means)

Claims (4)

Supply combustion gas containing odorant to general gas combustion equipment installed by consumers and supply combustion gas not containing odorant to specific gas equipment installed by consumers using a pipeline A method of supplying combustion gas,
The pipeline includes a double pipe composed of an outer pipe and an inner pipe inserted into the outer pipe. In the double pipe, the combustion gas containing the odorant is supplied to the outer pipe and the inner pipe. A method for supplying combustion gas, characterized in that a combustion gas that does not contain the odorant is caused to flow into a space formed by a pipe and flows into the inner pipe.   In the double pipe, the pressure (P1) of the combustion gas containing no odorant flowing in the inner pipe is larger than the pressure (P2) of the combustion gas containing the odorant flowing in the space. The combustion gas supply method according to claim 1, wherein: Pipeline for supplying combustion gas containing odorant to general gas combustion equipment installed by consumers and combustion gas not containing odorant to specific gas equipment installed by consumers There,
The pipeline includes a double pipe portion composed of a double pipe having an outer pipe and an inner pipe inserted into the outer pipe,
The double pipe section is a pipe for flowing the combustion gas not containing the odorant in the inner pipe, and a space formed by the outer pipe and the inner pipe is further formed in the odorant. It has a piping structure for flowing in the combustion gas.
The pipeline uses the pressure (P1) of the combustion gas that does not contain the odorant flowing in the inner pipe of the double pipe part, and the pressure of the combustion gas that contains the odorant that flows through the space part. (P2) A pipeline for supplying combustion gas, characterized by comprising pressure adjusting means for flowing larger.   The pipeline for supplying combustion gas according to claim 3, wherein the outer pipe constituting the double pipe section is an existing pipe for supplying the combustion gas containing the odorant. .

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