JP2021116850A - Biogas supply device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biogas supply device and a method for improving energy efficiency by making the flow rate of the supplied biogas uniform. A biogas supply device 11 can supply a biogas generated by a biogas generation unit 12 to a gas engine power generation device 14 via a gas delivery pipe 13, and is branched into the gas delivery pipe 13. A bypass route 15 is provided, which is composed of a recovery pipe 15a on the upstream side connected to the gas reservoir 16 and a supplementary pipe 15b on the downstream side extending from the gas reservoir 16 and joining the gas delivery pipe. A gas flow rate adjusting unit 17 is provided on the downstream side of the 15th. A back pressure valve 18 is attached to the recovery pipe 15a, and a pressure reducing valve 19 is attached to the filling pipe 15b. [Selection diagram] Fig. 1

Description

The present invention relates to a biogas supply device and method, and more particularly to a device and method for supplying biogas to a power generation facility or the like that uses biogas as fuel for an engine.

Biogas is one of the renewable energies mainly composed of methane gas, which can be produced from biomass (biological resources) by microbial fermentation or anaerobic digestion. In addition to those produced by energy crops, it can also be produced from biodegradable materials and organic waste such as biological excrement, sludge / sewage, and kitchen waste, and is used as fuel for power generation.

As a device for generating biogas, the concentration of hydrogen sulfide in the biogas obtained by methane fermentation of organic waste is calculated, and based on the value, hydrogen sulfide in the biogas is desulfurized while methane fermentation is performed. A technique for performing operation control is known (see, for example, Patent Document 1).

Further, as a system for driving a gas engine using biogas, a gas engine power generator equipped with an induction generator driven by a gas engine using biogas generated from biomass by a biogas generator as fuel is known. (See, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2006-247568 Japanese Unexamined Patent Publication No. 2006-087221

By the way, in consideration of power generation efficiency and equipment maintenance, it is desirable that the gas engine power generation device is operated so that the load is always constant, and for that purpose, it is necessary to constantly supply a constant amount of fuel.

However, in the biogas generator as in Patent Document 1, the amount of biogas produced varies greatly with time due to various factors. Therefore, when biogas is supplied as fuel from the biogas generator to the gas engine power generation device as in Patent Document 2, the biogas supply reference amount keeps the amount of biogas supplied to the gas engine power generation device constant. Therefore, it was necessary to set the lower limit of the amount of fluctuating biogas production.

Under such standard setting, it was not possible to fully utilize the capacity of the gas engine power generation device due to insufficient fuel supply, and more than the standard set due to fluctuations in the amount of production was generated. The surplus of biogas could not be utilized and was discarded, and it was not possible to supply energy-efficient biogas to the gas engine power generator.

Therefore, an object of the present invention is to provide a biogas supply device and method in which the flow rate of the supplied biogas is made uniform to improve energy efficiency.

In order to achieve the above object, the biogas supply device of the present invention is a biogas supply device that supplies biogas generated from a biogas raw material by a biogas generation unit to a gas engine power generation device via a gas distribution pipe. The gas delivery pipe is provided with a bypass path that branches and merges with the gas delivery pipe, and a gas reservoir capable of storing and delivering biogas is arranged on the bypass path, and the gas delivery pipe is provided. A gas flow rate adjusting unit for adjusting the flow rate of biogas supplied to the gas engine power generation device to a set reference gas flow rate is provided on the downstream side of the confluence position of the bypass path, and the bypass path is on the upstream side. When the flow rate of biogas flowing into the gas flow rate adjusting unit exceeds the reference gas flow rate by connecting the gas delivery pipe and the gas storage unit, the amount of biogas exceeding the reference gas flow rate is added to the gas. When the recovery pipe that flows into the gas storage from the distribution pipe is connected to the gas storage and the gas distribution pipe on the downstream side, and the flow rate of biogas flowing into the gas flow rate adjusting unit falls below the reference gas flow rate. It is characterized in that it is composed of a supplementary pipe that sends out an amount of biogas that is less than the reference gas flow rate from the gas storage to the gas delivery pipe.

In a preferred embodiment of the present invention, the gas delivery pipe is provided with a check valve for preventing backflow of biogas to the biogas generating section in a section bypassed by the bypass path, and the recovery is performed. A back pressure valve for applying a back pressure set to the biogas flowing into the bypass path from the gas delivery pipe through the recovery pipe is attached to the pipe, and the supplementary pipe is stored at high pressure in the gas storage. A pressure reducing valve for reducing the pressure of the biogas to a set pressure and a check valve for preventing the backflow of the biogas from the gas delivery pipe are attached.

In another preferred embodiment of the present invention, the gas delivery pipe is provided with a check valve for preventing backflow of biogas to the biogas generating section in a section bypassed by the bypass path. An electric valve is attached to each of the recovery pipe and the supplementary pipe, and the supplementary pipe is in reverse to prevent backflow of biogas from the gas delivery pipe to the downstream side of the electric valve of the supplementary pipe. A stop valve is attached, and a pressure gauge for detecting the pressure of biogas is provided on the upstream side of the gas delivery pipe with respect to the section bypassed by the bypass path. , It is formed so that the biogas of the reference gas flow rate can pass under the set reference gas pressure, and the gas flow rate adjusting unit is a gas flow meter that detects the gas flow rate flowing into the gas flow rate adjusting unit. The pressure gauge, the electric valve of the recovery pipe, the electric valve of the supplementary pipe, and the gas flow meter are electrically connected to each other, and the biogas detected by the pressure gauge is provided. When the pressure of the recovery pipe exceeds the reference gas pressure, the electric valve of the recovery pipe is opened and the electric valve of the supplementary pipe is closed, and the pressure of the biogas detected by the pressure gauge does not exceed the reference gas pressure. Further, when the gas flow rate detected by the gas flow meter falls below the reference gas flow rate, the gas flow control unit is provided to open the electric valve of the supplementary pipe and close the electric valve of the recovery pipe.

Further, in order to achieve the above object, the biogas supply method of the present invention generates biogas from a biogas raw material and supplies the generated biogas to a gas engine power generation device via a gas distribution pipe. In the method, a gas flow rate adjusting step of adjusting the flow rate of biogas supplied to the gas engine power generation device to a set reference gas flow rate under a set reference gas pressure, and a supply to the gas engine power generation device. The supply gas homogenization step includes a supply gas homogenization step of equalizing the fluctuation of the biogas flow rate to the reference gas flow rate, and the supply gas homogenization step detects the pressure of the biogas supplied to the gas delivery pipe. When the pressure of the biogas detected in the gas pressure detection step and the gas pressure detection step exceeds the reference gas pressure, the amount of biogas that gives a pressure exceeding the reference gas pressure is collected and stored in the gas storage means. When the pressure of the biogas detected in the surplus gas recovery step and the gas pressure detection step does not exceed the reference gas pressure and the biogas flow rate is lower than the reference gas flow rate, the surplus gas recovery step is performed. It is characterized by including a shortage gas delivery step in which the biogas stored in the gas storage means is delivered to the gas delivery means and the amount of biogas below the reference gas flow rate is supplemented.

According to the biogas supply device of the present invention, if the biogas flowing into the gas flow rate adjusting unit exceeds the reference gas flow rate, the surplus biogas is collected and stored in the gas reservoir, and if it falls below the reference gas flow rate, Since the shortage of biogas is supplemented from the gas reservoir, the flow rate of biogas supplied from the biogas generator can be made uniform to the reference gas flow rate, which is a sufficient amount for the gas engine power generation device. Biogas can be constantly supplied to improve the operating rate, reduce the amount of surplus biogas discarded, and improve energy efficiency.

Further, according to the biogas supply method of the present invention, by performing the above series of steps, the biogas supplied to the gas delivery means is surplus when the gas flow is controlled and exceeds the reference gas flow rate. The amount of biogas is collected and stored in the gas storage means, and the shortage of biogas when it falls below the standard gas flow rate is supplemented by the gas storage means, so the flow rate of biogas supplied from the biogas generation means. Can be made uniform to the standard gas flow rate, and a sufficient amount of biogas is constantly supplied to the gas engine power generation device to improve the operating rate, reduce the amount of surplus biogas discarded, and generate energy. Efficiency can be improved.

It is a schematic diagram which shows the 1st form example of the biogas supply apparatus of this invention. Similarly, it is a conceptual diagram which shows the time-dependent fluctuation of the amount of biogas supply. Similarly, it is a schematic diagram which shows the change of the gas flow according to the amount of biogas supply. It is a schematic diagram which shows the 2nd form example of the biogas supply device of this invention. Similarly, it is a flowchart which shows the homogenization control of biogas. Similarly, it is a schematic diagram which shows the change of the gas flow according to the amount of biogas supply.

1 to 3 are diagrams relating to the biogas supply device 11 which is an example of the first embodiment of the present invention, and FIGS. 4 to 6 are diagrams relating to the biogas supply device 22 which is an example of the second embodiment of the present invention. be.

As shown in FIG. 1, the biogas supply device 11 is configured so that the biogas generated from the biogas raw material by the biogas generation unit 12 can be supplied to the gas engine power generation device 14 via the gas distribution pipe 13. There is.

The gas delivery pipe 13 is provided with a bypass path 15 that branches and merges with the gas delivery pipe 13, and a gas reservoir 16 capable of storing and delivering biogas is arranged on the bypass path 15. Has been done. In the first embodiment of the present invention, the gas reservoir 16 is a high-pressure gas container 16a with a compressor 16b that compresses and stores biogas until the pressure reaches 1 MPa or more.

The bypass path 15 includes a recovery pipe 15a that connects the gas delivery pipe 13 on the upstream side to the high-pressure gas container 16a via the compressor 16b, and a supplementary pipe 15b that connects the high-pressure gas container 16a to the gas delivery pipe 13 on the downstream side. It is composed of and.

The gas delivery pipe 13 is provided with a gas flow rate adjusting unit 17 that adjusts the flow rate of biogas in the gas delivery pipe 13 to a preset amount on the downstream side of the confluence position of the bypass path 15. The gas flow rate adjusting unit 17 is formed so that the gas flow rate can be adjusted to a set amount by narrowing or expanding the internal valve according to the gas pressure applied to the gas flow rate adjusting unit 17.

Further, in the section of the gas delivery pipe 13 where the bypass path 15 bypasses, a first check valve 20 for preventing the backflow of biogas from the supplementary pipe 15b to the biogas generation unit 12 is attached.

A back pressure valve 18 is attached to the recovery pipe 15a to apply a predetermined back pressure to the biogas flowing from the gas delivery pipe 13 through the recovery pipe 15a into the bypass path 15. Further, the filling pipe 15b includes a pressure reducing valve 19 that reduces the pressure of the biogas stored at high pressure in the gas reservoir to a predetermined pressure, and a second check valve 21 that prevents the backflow of the biogas from the gas distribution pipe 13. And are attached.

As shown in FIG. 2, the amount (G) of biogas generated by the biogas generating unit 12 and supplied to the gas delivery pipe 13 varies with time (t) and is not constant, and gas engine power generation. It becomes excessive or insufficient with respect to the steady reference gas flow rate GS set according to the capacity of the device 14.

Therefore, assuming that the surplus gas flow rate that is the surplus of the reference gas flow rate GS is GE and the shortage gas flow rate that is the shortage of the reference gas flow rate GS is GD, the gas flow rate G supplied from the biogas generation unit 12 is G = It is expressed as GS + GE or G = GS-GD.

Further, the gas flow rate adjusting unit 17 in FIG. 1 is set so that the biogas having a reference gas flow rate of GS can pass through under a reference gas pressure PS of less than 1 MPa. The back pressure valve 18 is set so that a back pressure P'slightly higher than the reference gas pressure PS is applied, and the pressure reducing valve 19 uses the gas pressure of the biogas flowing from the high pressure gas container 16a as the reference gas pressure PS. It is set to reduce the pressure to.

As shown in FIG. 3A, when the gas flow rate supplied from the biogas generation unit 12 is G = GS + GE, the gas flow rate passing through the gas flow rate adjusting unit 17 is up to the reference gas flow rate GS, so the gas delivery pipe. The pressure P of the biogas in 13 becomes higher than the reference gas pressure PS.

At this time, the gas flow in the gas delivery pipe 13 becomes a pressure equal to or higher than the gas pressure that can pass through the back pressure valve 18 of the recovery pipe 15a. On the other hand, since the supplementary pipe 15b is provided with the second check valve 21, the biogas in the gas delivery pipe 13 flows back even if the pressure P of the biogas in the gas delivery pipe 13 becomes high. It does not flow to the pressure reducing valve 19.

Then, when the gas flow for the excess gas flow rate GE whose pressure exceeds the back pressure P'passes through the back pressure valve 18, the gas flow rate in the gas delivery pipe 13 returns to the reference gas flow rate GS, and the biotechnology in the gas delivery pipe 13 Since the gas pressure P also drops to the pressure P', the gas flow cannot pass through the back pressure valve 18.

Therefore, when the gas flow rate from the biogas generation unit 12 is G = GS + GE, the reference gas flow rate GS passes through the gas flow rate adjusting unit 17, while the gas flow for the surplus gas flow rate GE that cannot pass through is delivered by gas. It flows from the pipe 13 into the recovery pipe 15a, passes through the back pressure valve 18, is compressed by the compressor 16b, and then is recovered and stored in the high-pressure gas container 16a.

As shown in FIG. 3B, when the gas flow rate supplied from the biogas generation unit 12 is G = GS-GD, the gas flow rate passing through the gas flow rate adjusting unit 17 is smaller than the reference gas flow rate GS. , The pressure P of the biogas in the gas delivery pipe 13 becomes lower than the reference gas pressure PS.

At this time, the gas flow in the gas delivery pipe 13 becomes a gas pressure through which the gas flow can pass from the pressure reducing valve 19, and cannot pass through the back pressure valve 18 of the recovery pipe 15a.

On the other hand, since the first check valve 20 is provided in the section of the gas delivery pipe 13 where the bypass path 15 bypasses, even if the pressure P of the biogas in the gas delivery pipe 13 becomes low, it is compensated. The biogas in the tube 15b does not flow back and flow into the biogas generating section 12.

Therefore, when the gas flow rate from the biogas generating unit 12 is G = GS-GD, the gas flow rate is less than the reference gas flow rate GS passing through the gas flow rate adjusting unit 17 and is sent from the high pressure gas container 16a to the filling pipe 15b. The gas flow corresponding to the insufficient gas flow rate GD passes through the pressure reducing valve 19 and is replenished to the gas delivery pipe 13.

As described above, according to the biogas supply device 11 of the present invention, if the biogas flowing into the gas flow rate adjusting unit 17 exceeds the reference gas flow rate GS, the biogas corresponding to the surplus gas flow rate GE is recovered in the gas reservoir 16. -If the gas is stored and falls below the reference gas flow rate GS, the biogas corresponding to the insufficient gas flow rate GD is supplemented from the gas reservoir 16, so that the gas flow rate G that fluctuates with time, which is supplied from the biogas generator 12, is used as the reference gas. The flow rate can be made uniform to GS.

Therefore, the biogas supply device 11 constantly supplies a sufficient amount of biogas to the gas engine power generation device 14 to improve the operating rate, reduce the amount of surplus biogas discarded, and achieve energy efficiency. Can be improved.

Further, since the first check valve 20 is attached to the section of the gas delivery pipe 13 bypassed by the bypass path 15 and the second check valve 21 is attached to the supplementary pipe 15b, the bio in the gas delivery pipe 13 Since the backflow of gas is prevented and the generation of irregular gas flow can be suppressed, the biogas supplied from the biogas generation unit 12 can be efficiently homogenized.

Further, since the back pressure valve 18 is attached to the recovery pipe 15a and the pressure reducing valve 19 is attached to the filling pipe 15b, the gas flow rate adjusting unit 17 responds to an increase or decrease in the supply amount of biogas in the gas delivery pipe 13. The excess biogas is recovered to the recovery pipe 15a and the shortage of biogas is automatically replenished from the replenishment pipe 15b so that the pressure upstream of the gas is kept substantially constant. The biogas can be homogenized by a simple structure.

Moreover, by using the high-pressure gas container 16a provided with the compressor 16b that compresses the volume of the biogas to be stored as the gas storage 16, the required equipment can be reduced, so that the biogas supply device 11 can be downsized. Can be planned.

As shown in FIG. 4, the biogas supply device 22 which is the second embodiment of the present invention has the same basic configuration as the biogas supply device 11 of FIG. 1 which is the first embodiment of the present invention. However, the first electric valve 23 is attached to the recovery pipe 15a instead of the back pressure valve 18, and the second electric valve 24 is attached to the compensation pipe 15b instead of the pressure reducing valve 19. Both the first electric valve 23 and the second electric valve 24 are formed so that the internal valve can be opened and closed by electric control and the gas flow rate to be passed can be adjusted.

Further, a pressure gauge 25 for detecting the pressure of biogas is provided on the upstream side of the gas delivery pipe 13 from the branch position of the bypass path 15. The pressure gauge 25, the first electric valve 23 of the recovery pipe 15a, and the second electric valve 24 of the supplementary pipe 15b are electrically connected to the gas flow control unit 26, respectively. The electric valves 23 and 24 are formed so as to be openable and closable according to the gas pressure detected by the total 25.

The flow rate G of the biogas supplied from the biogas generation unit 12 to the gas delivery pipe 13 is the same as that of the biogas supply device 11 of FIG. 2, and G = GS + GE or G = GS-GD.

Further, the gas flow rate adjusting unit 17 also has a reference gas flow rate GS under a reference gas pressure PS of less than 1 MPa with respect to the reference gas flow rate GS, similarly to the biogas supply device 11. It is formed so that the gas flow rate can be adjusted to a set amount by narrowing or opening the internal valve according to the gas pressure applied to the gas flow rate adjusting unit 17.

The gas flow rate adjusting unit 17 is provided with a gas flow meter 17a electrically connected to the gas flow control unit 26 for detecting the gas flow rate flowing into the gas flow rate adjusting unit 17, and the gas flow control unit 26 is provided. In addition to the gas pressure described above, the electric valves 23 and 24 can be opened and closed according to the gas flow rate detected by the gas flow meter 17a.

Further, when the gas flow is designed on the downstream side of the second electric valve 24 on the premise that the gas flow is, for example, a low pressure of less than 1 MPa, a pressure reducing valve is provided on the upstream side of the second electric valve 24. It is desirable to take measures so that the pressure of 1 MPa or more stored in the high-pressure gas container 16a is not directly applied.

In the biogas supply device 22, the biogas supply method to the gas engine power generation device 14 is performed according to the following steps.

When the biogas generated by the biogas generating unit 12 is supplied to the gas distribution pipe 13, a gas flow rate adjusting step is performed in which the flow rate of the supplied biogas is adjusted to the reference gas flow rate GS by the gas flow rate adjusting unit 17. Will be.

Further, a supply gas equalization step of equalizing the fluctuation of the flow rate of the biogas supplied to the gas delivery pipe 13 to the reference gas flow rate GS is performed as follows.

First, a gas pressure detection step is performed in which the pressure of the biogas supplied to the gas delivery pipe 13 is detected by the pressure gauge 25.

When the pressure P of the biogas detected in the gas pressure detection step exceeds the reference gas pressure PS, the amount of biogas that gives the pressure exceeding the reference gas pressure PS is collected and stored in the gas reservoir 16 by the gas flow control unit 26. A surplus gas recovery process is performed.

Next, when the pressure P of the biogas detected in the gas pressure detection step does not exceed the reference gas pressure PS, the gas flow rate detection step of detecting the flow rate of the biogas flowing into the gas flow rate adjusting unit 17 by the gas flow meter 17a. Is done.

Further, when the flow rate G of the biogas detected in the gas flow rate detection step falls below the reference gas flow rate GS, the biogas stored in the gas reservoir 16 in the surplus gas recovery step is transferred to the gas delivery pipe by the gas flow control unit 26. A deficient gas delivery step is performed in which the amount of biogas delivered to 13 is supplemented to compensate for the lower pressure.

Here, the gas flow control in the supply gas homogenization step is performed as follows.
As shown in FIG. 5, first, the pressure P of the biogas supplied to the gas delivery pipe 13 in the gas pressure detection step is detected by the pressure gauge 25 (step S1), and is detected by the gas flow control unit 26. A comparison is made between the obtained gas pressure P and the reference gas pressure PS (step S2).

When the detected gas pressure P exceeds the reference gas pressure PS, the gas flow control unit 26 determines that the gas flow rate G exceeds the reference gas flow rate GS (G = GS + GE), and determines that the recovery pipe 15a is the first. A command is issued to the electric valve 23 to open the valve so that the excess gas flow rate GE flows, and a command to close the valve is issued to the second electric valve 24 of the supplementary pipe 15b. The first electric valve 23 that has received the command to that effect opens the valve, and the second electric valve 24 that has received the command to that effect closes the valve (step S3).

As shown in FIG. 6A, the gas flow at this time is a surplus gas that gives a pressure exceeding the reference gas pressure PS while the gas flow corresponding to the reference gas flow rate GS passes through the gas flow rate adjusting unit 17. The gas flow corresponding to the flow rate GE flows from the gas distribution pipe 13 into the recovery pipe 15a, passes through the first electric valve 23, is compressed by the compressor 16b, and is then collected and stored in the high-pressure gas container 16a.

Further, when the pressure P of the biogas detected in the gas pressure detection step does not exceed the reference gas pressure PS, the gas flow control unit 26 causes the flow rate of the biogas flowing into the gas flow rate adjusting unit 17 to be the gas flow meter 17a. (Step S4), and the detected gas flow rate G and the reference gas flow rate GS are compared (step S5).

When the detected gas flow rate G is lower than the reference gas flow rate GS (G = GS-GD), the gas flow control unit 26 issues a valve closing command to the first electric valve 23 of the recovery pipe 15a and compensates for it. A command is issued to the second electric valve 24 of the pipe 15b to open the valve so that the insufficient gas flow rate GD flows. The first electric valve 23 that has received the command to that effect closes the valve, and the second electric valve 24 that has received the command to that effect opens the valve (step S6).

As shown in FIG. 6B, the gas flow at this time is such that the gas flow corresponding to the insufficient gas flow rate GD sent out from the high-pressure gas container 16a passes through the replenishment pipe 15b and the second electric valve 24. It is filled in the delivery pipe 13, and the gas flow corresponding to the reference gas flow rate GS passes through the gas flow rate adjusting unit 17.

On the other hand, when the detected gas flow rate G is not lower than the reference gas flow rate GS, that is, when the gas flow rate G is equal to the reference gas flow rate GS (G = GS), the gas flow control unit 26 is the first of the recovery pipe 15a. (1) A command to close the valve is issued to the electric valve 23, and a command to close the valve is issued to the second electric valve 24 of the filling pipe 15b. The first electric valve 23 that has received the command to that effect closes the valve, and the second electric valve 24 that has received the command to that effect closes the valve (step S7).

The gas flow at this time passes through the gas flow rate adjusting unit 17 as it is without being recovered or compensated for the bypass path 15.

As described above, according to the biogas supply device 22 of the present invention, by performing the above-mentioned series of steps, the gas flow is controlled with respect to the biogas supplied to the gas delivery pipe 13 to obtain the reference gas flow rate GS. The biogas for the surplus gas flow rate GE when it exceeds the standard gas flow rate GE is collected and stored in the gas reservoir 16, and the biogas for the insufficient gas flow rate GD when the gas flow rate falls below the reference gas flow rate GS is supplemented from the gas storage device 16. The biogas flow rate G supplied from the biogas generation unit 12 can be made uniform with the reference gas flow rate GS and supplied to the gas engine power generation device 14.

Therefore, the biogas supply device 22 and the biogas supply method using the biogas supply device 22 constantly supply a sufficient amount of biogas to the gas engine power generation device 14 to improve the operating rate and the surplus biogas. It is possible to reduce the amount of waste and improve energy efficiency.

Further, since the first check valve 20 is attached to the section of the gas delivery pipe 13 bypassed by the bypass path 15, the biogas generation unit 12 of the biogas delivered from the supplementary pipe 15b to the gas delivery pipe 13 Since the second check valve 21 is attached to the filling pipe 15b, the backflow of the biogas in the gas delivery pipe 13 to the filling pipe 15b is prevented.

Therefore, the generation of irregular gas flow can be suppressed, and the gas flow can be controlled reliably, so that the biogas supplied from the biogas generation unit 12 can be efficiently homogenized.

Further, the gas flow control unit 26 determines the first electric valve 23 of the recovery pipe 15a and the second electric power of the filling pipe 15b according to the gas pressure detected by the pressure gauge 25 and the flow rate detected by the gas flow meter 17a. By controlling the opening and closing of the valve 24, excess biogas can be recovered to the recovery pipe 15a and insufficient biogas can be supplemented from the supplement pipe 15b, so that the biogas supplied from the biogas generation unit 12 can be reliably secured. Can be homogenized.

Moreover, by using the high-pressure gas container 16a provided with the compressor 16b that compresses the volume of the biogas to be stored as the gas storage 16, the required equipment can be reduced, so that the biogas supply device 22 can be downsized. Can be planned.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the invention. For example, in this embodiment, a high-pressure gas container with a compressor is used as the gas storage device, but the high-pressure gas container does not necessarily have to be a high-pressure gas container as long as the biogas can be stored and delivered, and the biogas is less than 1 MPa. A gas holder that stores at the pressure of, a liquefied gas storage tank that liquefies and stores biogas, a solid storage container that stores biogas by methanehydration, or a combination thereof can be used as a gas storage device. good.

Further, in this embodiment, the gas flow rate adjusting unit is formed so that the internal valve can be throttled or widened according to the gas pressure, but such a gas flow rate adjusting unit is not necessarily such if the gas flow rate can be adjusted to a set amount. It is not necessary to configure it, and a pressure detector is provided inside or at the position closest to the upstream side of the gas delivery pipe so that the gas flow rate can be adjusted to the set amount according to the detected pressure, or so-called mass flow. It may be used as a controller, and when the pressure on the downstream side is adjusted to be substantially constant, a throttle having a constant opening such as an orifice may be used.

11 ... Biogas supply device, 12 ... Biogas generator, 13 ... Gas delivery pipe, 14 ... Gas engine power generation device, 15 ... Bypass path, 15a ... Recovery pipe, 15b ... Compensation pipe, 16 ... Gas reservoir, 17 ... Gas flow control unit, 17a ... Gas flow meter, 18 ... Back pressure valve, 19 ... Pressure reducing valve, 20 ... First check valve, 21 ... Second check valve, 22 ... Biogas supply device, 23 ... First electric valve , 24 ... Second electric valve, 25 ... Pressure gauge, 26 ... Gas flow control unit

Claims (5)

In a biogas supply device that supplies biogas generated from a biogas raw material by a biogas generator to a gas engine power generation device via a gas distribution pipe.
The gas delivery pipe is provided with a bypass path that branches and merges with the gas delivery pipe, and a gas reservoir capable of storing and delivering biogas is provided on the bypass path, and the gas delivery pipe is provided. A gas flow rate adjusting unit for adjusting the flow rate of biogas supplied to the gas engine power generation device to a set reference gas flow rate is provided on the downstream side of the confluence position of the bypass path.
The bypass path connects the gas delivery pipe and the gas storage on the upstream side, and when the flow rate of biogas flowing into the gas flow rate adjusting unit exceeds the reference gas flow rate, the amount exceeds the reference gas flow rate. The flow rate of the biogas flowing into the gas flow rate adjusting unit by connecting the recovery pipe for flowing the biogas from the gas delivery pipe into the gas storage and the gas storage and the gas delivery pipe on the downstream side is A biogas supply device comprising a supplementary pipe that sends out an amount of biogas that is less than the reference gas flow rate from the gas storage to the gas delivery pipe when the gas flow rate is lower than the reference gas flow rate. The gas delivery pipe is provided with a check valve for preventing the backflow of biogas to the biogas generating portion in a section bypassed by the bypass path.
A back pressure valve for applying a back pressure set to the biogas flowing into the bypass path from the gas delivery pipe through the recovery pipe is attached to the recovery pipe, and a high pressure is applied to the gas reservoir in the supplement pipe. The first aspect of claim 1, wherein a pressure reducing valve for reducing the pressure of the biogas stored in the above gas to a set pressure and a check valve for preventing the backflow of the biogas from the gas delivery pipe are attached. Biogas supply device. The gas delivery pipe is provided with a check valve for preventing the backflow of biogas to the biogas generating section in the section where the bypass path bypasses.
An electric valve is attached to each of the recovery pipe and the supplementary pipe, and the supplementary pipe prevents backflow of biogas from the gas delivery pipe to the downstream side of the electric valve of the supplementary pipe. A check valve is installed,
A pressure gauge for detecting the pressure of biogas is provided on the upstream side of the gas delivery pipe with respect to the section bypassed by the bypass path.
The gas flow rate adjusting unit is formed so as to allow the biogas of the reference gas flow rate to pass under a set reference gas pressure, and the gas flow rate adjusting unit has a gas flow rate flowing into the gas flow rate adjusting unit. A gas flow meter is provided to detect
The pressure gauge, the electric valve of the recovery pipe, the electric valve of the supplementary pipe, and the gas flow meter are electrically connected to each other, and the pressure of the biogas detected by the pressure gauge is the reference gas. When the pressure is exceeded, the electric valve of the recovery pipe is opened and the electric valve of the supplementary pipe is closed, the pressure of the biogas detected by the pressure gauge does not exceed the reference gas pressure, and the gas flow meter The first aspect of claim 1, wherein the gas flow control unit includes a gas flow control unit that opens the electric valve of the supplementary pipe and closes the electric valve of the recovery pipe when the gas flow rate detected by is lower than the reference gas flow rate. Bio gas supply device. The gas storage is a high-pressure gas container that compresses and stores biogas until it reaches a pressure of 1 MPa or more, a gas holder that stores biogas at a pressure of less than 1 MPa, and a liquefied gas storage tank that liquefies and stores biogas. The bio according to any one of claims 1 to 3, wherein the biogas is a gas reservoir composed of any one or a combination of two or more of solid storage containers for storing biogas in methane hydrate. Gas supply device. In a biogas supply method in which biogas is generated from a biogas raw material and the generated biogas is supplied to a gas engine power generation device via a gas distribution pipe.
A gas flow rate adjusting step of adjusting the flow rate of biogas supplied to the gas engine power generation device to a set reference gas flow rate under a set reference gas pressure, and a gas flow rate adjusting step.
The supply gas equalization step of equalizing the fluctuation of the flow rate of the biogas supplied to the gas engine power generation device to the reference gas flow rate is included.
The supply gas homogenization step includes a gas pressure detection step of detecting the pressure of the biogas supplied to the gas delivery pipe and a gas pressure detection step.
When the pressure of the biogas detected in the gas pressure detection step exceeds the reference gas pressure, the excess gas recovery step in which the amount of biogas that gives a pressure exceeding the reference gas pressure is recovered and stored in the gas storage means. When,
When the pressure of the biogas detected in the gas pressure detection step does not exceed the reference gas pressure and the flow rate of the biogas falls below the reference gas flow rate, the gas is stored in the gas storage means in the surplus gas recovery step. A biogas supply method comprising a deficient gas delivery step in which the biogas is delivered to the gas delivery pipe and the amount of biogas below the reference gas flow rate is supplemented.

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