JP2003042397A - Gas usage method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new usage method for gas in general containing a biogas. SOLUTION: In gas storage equipment provided with a compressor for compressing the gas, a storage means for storing the gas, and a pipe for carrying the gas between the compressor and the storage means, a branch pipe is provided in an intermediate part of the pipe, a back pressure means is provided in the pipe between the branch part and the gas storage means, and a pressure reduction means is provided in the branch pipe. Thus, the gas of which pressure is reduced but still relatively high is supplied to consumption equipment in this gas usage method and device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas storage facility having a compressor for compressing gas, storage means for storing the gas, and piping for transporting the gas between the compressor and the storage means. Provide a branch pipe in the middle of the pipe,
A back pressure means is provided in the pipe between the branch portion and the gas storage means, and a decompression means is provided in the branch pipe to supply a gas having a relatively high pressure, which is decompressed by the decompression means. And a gas utilization method and device.

[0002]

2. Description of the Related Art Biological treatment of organic waste generated in sewage treatment plants, food factories, beer factories, livestock farms produces methane, carbon dioxide, hydrogen sulfide, thiols, toluene, siloxanes, etc. Biogas is generated. In recent years, research has been actively conducted on a method of adsorbing and storing biogas in order to effectively use such biogas as an energy source.

[0003]

However, other than the above storage method, much research has not been done on how to use biogas. The present invention seeks to propose a new usage method for general gases including biogas.

[0004]

SUMMARY OF THE INVENTION The present invention is a gas storage facility having a compressor for compressing gas, a storage means for storing the gas, and piping for transporting the gas between the compressor and the storage means. In the above, a branch pipe is provided in the middle of the pipe, a back pressure means is provided in the pipe between the branch portion and the gas storage means, and a pressure reducing means is provided in the branch pipe, thereby reducing the gas pressure. The present invention relates to a gas utilization device for supplying gas to consumption equipment. The present invention also provides such a gas utilization device in which the consumption facility is one or a plurality of gas turbines or micro gas turbines, and which uses the gas as fuel for power generation. The present invention also provides such a gas utilization device in which the back pressure means is a back pressure valve or an orifice. The present invention also provides such a gas utilization device in which the decompression means is a decompression valve or an orifice. The present invention also provides, in such a gas utilization device, a gas utilization device in which the gas is a gas containing methane as a main component. The present invention is also a gas utilization apparatus, wherein the gas containing methane as a main component is derived from biogas generated by a biological treatment of an organic matter, and a gas having a desulfurization facility in front of the compressor. Is provided. The present invention also provides such a gas utilization device, wherein the storage means is an adsorption gas holder. The present invention also provides, in such a gas utilization device, a gas utilization device having a dehumidification mechanism for removing moisture in the gas in a pipe or a branch pipe between the compressor and the storage means. The present invention also provides, in such a gas utilization device, a gas utilization device having a device for removing gases other than methane, sulfur compounds, carbon dioxide, and moisture downstream of the dehumidifying mechanism.

The present invention is also a method of utilizing gas using the above-mentioned gas utilization device, wherein the gas compressor is used to connect the pipe between the compressor and the back pressure means and between the branch portion and the pressure reducing means. A method of using a gas, which comprises increasing the pressure of a gas in a branch pipe, then reducing the pressure of the gas by the decompression means, and supplying a gas whose decompressed gas pressure is higher than the pressure in the storage means to a consumption facility. Is provided.

By providing the back pressure means, the pressure between the compression means and the back pressure means can be increased, and a gas pressure higher than the gas pressure in the storage means can be obtained. This relatively high pressure makes it possible to operate consuming equipment which cannot be operated at relatively low gas pressures in the storage means. A gas turbine or a micro gas turbine may be present as such a consumption facility.

[0007]

A back pressure valve or an orifice may be used as the back pressure means.

A pressure reducing valve or an orifice can be used as the pressure reducing means.

The gas preferably contains methane as a main component. The gas containing methane as a main component is preferably derived from biogas generated by biological treatment of organic substances. "Derived from" here means
It may be used as it is, or preferably desulfurized and decarbonated.

The biogas includes digestive gas and landfill gas. This biogas contains methane as a main component and contains carbon dioxide, sulfur compounds such as hydrogen sulfide and thiol, hydrogen gas, toluene, siloxane and the like. Since the sulfur compound has a tendency to corrode the device, it is preferably removed in advance. As the desulfurization method,
There are dry type and wet type. A molding desulfurization agent system is often used in the dry desulfurization method, and as the desulfurization agent, a molding desulfurization agent pelletized with iron powder, clay or the like is used. In the wet desulfurization method,
There are water washing type, alkaline washing type, chemical regenerating type and the like.

The biogas contains a large amount of carbon dioxide (usually about 40% by volume), which lowers the calorific value per unit volume of biogas as a fuel, making gas transportation and gas storage inefficient. Therefore, it is preferable to remove it. Examples of the method include those having an adsorption tower filled with a carbon dioxide adsorbent such as activated carbon, zeolite, or a metal oxide, a gas separation membrane, or a porous hollow fiber membrane.

The storage means is preferably an adsorption type gas holder. This makes it possible to store a large amount of gas at low pressure. Examples of this adsorbent include activated carbon, artificial zeolite, natural zeolite, silica gel, organometallic complexes (copper fumarate, copper terephthalate, etc.).

It is preferable that a dehumidifying mechanism for removing water in the gas is present in the pipe or the branch pipe between the compressor and the storage means. This dehumidification mechanism may be located anywhere between the branch and the compressor, storage means or decompression means. This is because this moisture may reduce the adsorption performance of the adsorbent in the storage means and may corrode the pipes and the consumption equipment.

A device for removing gases other than methane, sulfur compounds, carbon dioxide and water such as toluene and siloxane is preferably placed downstream of the dehumidifying mechanism. These can be adsorbed and removed with activated carbon.

An example of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a digestion tank, 2 is a desulfurization tower, 3 is a carbon dioxide removal device, and 4 is a low pressure gas holder. In the digestion tank 1, since the types of raw materials to be charged into the digestion tank 1 are not constant and the supply amount thereof is not constant, the amount of biogas produced is also not constant. Therefore, the low pressure gas holder 4 is preferably a variable capacity type. Reference numeral 5 shows a pipe from the gas holder to the facility used. 10 is a desulfurization tower. In this figure, what is drawn with a dotted line means that it is not always necessary. In the desulfurization tower 2, the content of sulfur compounds such as hydrogen sulfide is usually about 1 to 10 ppm. In the desulfurization tower 10, desulfurization is performed so that the content of sulfur compounds such as hydrogen sulfide in the gas is usually less than about 1 ppm. The content of sulfur compounds such as hydrogen sulfide is usually about 1
If this gas can be used in the range of about 10 ppm, the desulfurization tower 10 is not necessary. When desiring to protect the compressor 11 from corrosion and to use it for a long period of time, it is preferable to provide the desulfurization tower 10. The operation of the compressor 11 is controlled by the storage amount of the low pressure gas holder. 12 is a dehumidifying mechanism, and 1
3 is a device for removing other gas components such as toluene and siloxane gas other than methane.

Reference numeral 14 is a back pressure valve, and 15 is an adsorption type gas holder. The gas pressure in the gas holder 15 is, for example, a gauge pressure of 200 kPa. Reference numeral 16 denotes a pipe from the gas holder to the facility used. Facilities for this use include hot water boilers, gas engines (power generation facilities), and LPG.
There are equipment used for filling cylinders and consumption by distribution to households by piping. Reference numeral 21 is a pressure reducing valve, and 22 is a micro gas turbine (consumption facility in the present invention). A gas turbine may be used instead of the micro gas turbine. The pressure of biogas supplied to the micro gas turbine 22 is, for example, 300 kPa.
By providing the back pressure means such as the back pressure valve, the pressure between the pipes between the compressor and the storage means can be increased, and by further providing the pressure reduction means, the pressure suitable for the consumption equipment can be obtained. it can. According to the present invention, as described above, it becomes possible to use the fuel gas such as biogas even in a consumption facility having a pressure higher than the gas pressure in the gas holder 15.

Steam or hot water can be produced by utilizing the sensible heat of the exhaust gas of the micro gas turbine. Moreover, the digestion tank 1 can be heated with the obtained steam or hot water. Further, the electric power obtained by the micro gas turbine or the like can be used in the treatment plant. For example, it can be used as electric power for a blower of an aeration tank, a gas compressor for supplying digestion gas, and the like.

[0018]

According to the present invention, not only is gas compressed and stored in a storage container and then used for consumption equipment,
The gas can be easily supplied to the consumption facility that requires the gas at a pressure higher than that of the gas storage container.

[Brief description of drawings]

FIG. 1 is a flow sheet showing an embodiment of a gas utilization apparatus of the present invention.

[Explanation of symbols]

1 ... digestion tank 2 ... Desulfurization tower 3 ... Decarbonization tower 4 ... Low pressure gas holder 5 ... Piping to the equipment used 10 ... Desulfurization tower 11 ... Compressor 12 ... Dehumidifying mechanism 13 ... Equipment for removing other gas components 14 ... Back pressure valve 15 ... Adsorption type gas holder 16… Piping to equipment used 21 ... Pressure reducing valve 22 ... Micro gas turbine

Claims (10)

[Claims] 1. A gas storage facility comprising a compressor for compressing gas, a storage means for storing the gas, and a pipe for transporting the gas between the compressor and the storage means, and a branch in the middle of the pipe. A pipe is provided, and a back pressure unit is provided in the pipe between the branched portion and the gas storage unit, and a decompression unit is provided in the branch pipe so that the gas decompressed by the gas is supplied to the consumption facility. Utilization device. 2. The gas utilization apparatus according to claim 1, wherein the consumption facility is one or a plurality of gas turbines or micro gas turbines, and the gas is used as fuel to generate electricity. 3. The gas utilization apparatus according to claim 1, wherein the back pressure means is a back pressure valve or an orifice. 4. The gas utilization apparatus according to claim 1, wherein the pressure reducing means is a pressure reducing valve or an orifice. 5. The gas utilization apparatus according to claim 1, wherein the gas is a gas containing methane as a main component. 6. The gas according to claim 5, wherein the gas containing methane as a main component is derived from biogas generated by biological treatment of an organic matter, and a desulfurization facility is provided in front of the compressor. Utilization device. 7. The gas utilization apparatus according to claim 1, wherein the storage means is an adsorption type gas holder. 8. The gas utilization device according to claim 1, further comprising a dehumidification mechanism for removing water in the gas, in a pipe or a branch pipe between the compressor and the storage means. 9. The gas utilization apparatus according to claim 8, further comprising a device for removing gases other than methane, sulfur compounds, carbon dioxide, and moisture downstream of the dehumidifying mechanism. 10. A method of using gas using the apparatus according to claim 1, wherein the gas compressor is used to connect the pipe between the compressor and the back pressure means, the branch portion, and the pipe. Increasing the pressure of the gas in the branch pipe between the depressurizing means, then depressurizing this gas by the depressurizing means, and supplying to the consuming facility a gas whose depressurized gas pressure is higher than the pressure in the storage means. How to use gas.