JP2005240863A - High pressure gas decompression facilities - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact high pressure gas decompression facilities which receive high pressure natural gas from an upstream side and supplies the same to a downstream side after decompression to a predetermined pressure, capable of stably and efficiently heating natural gas before decompression, and of performing appropriate pressure adjustment and of stably supplying natural gas. <P>SOLUTION: Natural gas decompressed by a pressure reducing valve 23 and water pumped out from a water tank 26 are used. A fuel cell 21 for taking out hot water and electric power is provided. Hot water which is taken out is led to a heat exchanger 21. Natural gas before decompression is heated by heat exchange. Electric power which is taken out is stored in a storage battery 25 to cover electric power necessary for an electric heater 22 for heating natural gas before decompression. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

    The present invention relates to a high-pressure gas decompression facility that receives high-pressure natural gas (including city gas) from the upstream side, decompresses the gas to a predetermined pressure, and supplies the pressure to the downstream side.

  In the supply line of natural gas including city gas, a pressure reducing valve is provided in the middle of the supply line, and the high pressure natural gas supplied from the upstream side is reduced to a predetermined pressure by the pressure reducing valve and regulated to the downstream side. It comes to supply.

At that time, if the high-pressure natural gas is depressurized by the pressure reducing valve, the temperature will decrease by about 0.6 ° C. for every 1 kg / cm ² depressurization, so the natural gas temperature after depressurization may be below freezing point, and thereafter May adversely affect the piping and equipment.

  Therefore, in order to prevent such an adverse effect of the temperature drop due to the decompression, the natural gas before decompression is preliminarily heated with a boiler or the like and then decompressed.

  However, if the boiler is operated by an energy source such as fuel or power supplied from the outside, power will not be supplied at the time of a power failure, and the decompression equipment will be stopped, etc. It becomes impossible to supply.

  Thus, a high-pressure gas decompression facility is disclosed that makes it unnecessary to supply fuel or electric power from the outside, and can decompress the city gas after heating it in advance even during a power failure (see, for example, Patent Document 1). .

As shown in FIG. 2, the high-pressure gas decompression facility described in Patent Document 1 includes a heat exchanger 75, a decompression turbine 74, and a governor (a kind of decompression valve) 73 sequentially from the upstream side 71 toward the downstream side 72. The generator 77 is driven by the output of the decompression turbine 74, the heat pump 76 is operated by this electric power, the heat is absorbed from the surrounding environment, and the natural gas before decompression is heated by the heat exchanger 75. It is.
JP-A-8-121699

  However, the high-pressure gas decompression facility described in Patent Document 1 first decompresses the city gas by a decompression turbine, converts the energy generated in the decompression process of the decompression turbine into mechanical energy as a rotational force, and takes it out. Because of this type, the energy extracted from the decompression turbine always changes due to the time change and daily change of the pressure of the city gas before decompression, and the output of the heat pump is affected by the outside air temperature. As a result, stable city gas is not heated, which adversely affects the downstream piping. Furthermore, since the decompression process by the decompression turbine is almost isentropic expansion, unlike the decompression process by the governor, since the temperature at the outlet side of the decompression turbine is significantly reduced, the temperature decrease is also expected. Therefore, it is necessary to heat the city gas before decompression significantly, which is not an efficient heating method. In addition, since the decompression turbine and the heat pump are used, the scale of the decompression facility increases, and problems such as vibration and noise due to mechanical drive also occur.

  The present invention has been made to solve the above problems, and is a high-pressure gas decompression facility that receives high-pressure natural gas from the upstream side, depressurizes it to a predetermined pressure, and supplies it to the downstream side. To provide a compact high-pressure gas decompression equipment that can stably and efficiently heat natural gas, can perform appropriate pressure regulation, and can stably supply natural gas. It is the purpose.

  In order to solve the above problems, the present invention has the following features.

  [1] A high-pressure gas decompression facility that receives high-pressure natural gas from the upstream side, depressurizes it to a predetermined pressure and supplies it to the downstream side, and a fuel cell for taking out hot water using the natural gas after decompression; A heat exchanger for heating the hot water taken out by the fuel cell and the natural gas before decompression to heat the natural gas before decompression, and a decompression for decompressing the heated natural gas to a predetermined pressure A high-pressure gas decompression facility comprising a valve.

  [2] A high-pressure gas decompression facility that receives high-pressure natural gas from the upstream side, depressurizes it to a predetermined pressure and supplies it to the downstream side, and a fuel cell for taking out electric power using the natural gas after decompression; It has heating means for heating the natural gas before decompression using the electric power taken out by the fuel cell, and a decompression valve for decompressing the heated natural gas to a predetermined pressure. High pressure gas decompression equipment.

  [3] A high-pressure gas decompression facility that accepts high-pressure natural gas from the upstream side, depressurizes it to a predetermined pressure and supplies it to the downstream side, and is a fuel cell for extracting hot water and electric power using the decompressed natural gas A heat exchanger for exchanging heat between the hot water taken out by the fuel cell and the natural gas before decompression to heat the natural gas before decompression, and before depressurization using the electric power taken out by the fuel cell A high-pressure gas decompression facility comprising heating means for heating the natural gas and a pressure reducing valve for decompressing the heated natural gas to a predetermined pressure.

  In the present invention, since the natural gas before decompression is heated using the energy extracted by the fuel cell using the natural gas regulated to a constant pressure by the decompression valve, the pressure of the natural gas before decompression is increased. Regardless of the time change and daily change of the natural gas, it is possible to stably heat natural gas before decompression without the need for external energy supply, and it is necessary to perform significant heating as in the case of using a decompression turbine. Therefore, it is possible to efficiently heat natural gas before decompression. Thereby, the pressure regulation of natural gas can be performed appropriately, and natural gas can be supplied stably. In addition, since a fuel cell that extracts energy based on a chemical reaction is used, there is little generation of mechanical vibration and noise, and a compact decompression facility can be achieved.

  An embodiment of the present invention will be described with reference to the flowchart shown in FIG.

  In FIG. 1, reference numeral 1 denotes a high-pressure gas decompression facility according to an embodiment of the present invention, in which a high-pressure natural gas supplied from an upstream natural gas line 2 is decompressed to a predetermined pressure to downstream natural gas line. 3 is supplied.

  The high-pressure gas decompression facility 1 has a path 11 connecting the upstream natural gas line 2 and the downstream natural gas line 3, and the heat exchanger 21 is located on the path 11 from the upstream side toward the downstream side. And an electric heater 22 and a pressure reducing valve 23. The natural gas before decompression is heated by the heat exchanger 21 and the electric heater 22 and then decompressed to a predetermined pressure by the decompression valve 23.

  Further, the high-pressure gas pressure regulation equipment 1 includes a fuel cell 24, a storage battery 25, a water tank 26, and a pump 27, and the natural gas decompressed by the pressure reducing valve 23 passes through a route 12 branched from the route 11. Then, the water pumped out from the water tank 26 by the pump 27 is supplied to the fuel cell 24 via the path 13.

  The fuel cell 24 takes out hot water and electric power using the supplied natural gas and water, the taken out hot water is guided to the heat exchanger 21 via the path 14, and the taken out electric power passes through the path 16 Is stored in the storage battery 25.

  The hot water guided to the heat exchanger 21 is heat-exchanged with the natural gas before decompression in the heat exchanger 21 to heat the natural gas before decompression, and then becomes low-temperature water, and enters the water tank 26 via the path 15. Returned.

  In addition, the electric power stored in the storage battery 25 is supplied to the electric heater 22 via the path 16 and also supplied to the hump 27 via the path 17, and is necessary for the operation of the electric heater 22 and the hump 27. Cover power.

  In addition to the above, valves such as an emergency shutoff valve 31 and a filter 32 on the upstream side and a ball valve 33 on the downstream side are provided on the path 11, and a pressure gauge is provided between the emergency shutoff valve 31 and the filter 32. 34a, a thermometer 35a between the filter 32 and the heat exchanger 21, a thermometer 35b between the heat exchanger 21 and the electric heater 22, a thermometer 35c between the electric heater 22 and the pressure reducing valve 23, and a pressure reducing valve Measuring instruments such as a pressure gauge 34 b and a thermometer 35 d are attached between the ball valve 33 and the ball valve 33. The emergency shut-off valve 31 is operated by electric power supplied from the storage battery 25 via the path 18. Further, when there is a margin, electric power can be supplied from the storage battery 25 via the path 19 to the outside.

  Then, the high-pressure natural gas supplied from the upstream natural gas supply line 2 is reduced to a predetermined pressure and supplied to the downstream natural gas supply line 3 using the high-pressure gas decompression equipment 1 having the above-described configuration. The situation to be described is described below.

  First, the high-pressure natural gas supplied from the natural gas supply line 2 passes through the emergency shutoff valve 21 and the filter 32, is led to the heat exchanger 5, and is then heated by the electric heater 22.

  At that time, the natural gas before decompression is heated to a predetermined temperature by the electric heater 22 for a short period immediately after the start of operation in which hot water having a sufficient operation temperature cannot be supplied from the fuel cell 24 to the heat exchanger 21.

  If hot water having a sufficient operating temperature can be supplied from the fuel cell 24 to the heat exchanger 21, the natural gas led to the heat exchanger 21 is heated by heat exchange with the hot water supplied from the fuel cell 24. The At that time, both the heat exchanger 21 and the electric heater 4 may be used for heating to a predetermined temperature, or only the heat exchanger 21 may be used for heating to a predetermined temperature, or the electric heater 22 may be used. It is also possible to heat to a predetermined temperature using only this.

  Then, the high-pressure natural gas that has been preheated to a temperature that can prevent the adverse effect of the temperature drop due to the reduced pressure by the heat exchanger 21 or the electric heater 22 is guided to the pressure reducing valve 23 and is reduced to a predetermined constant pressure. Then, it is supplied to the natural gas supply line 3 on the downstream side.

  A part of the natural gas decompressed by the pressure reducing valve 23 is supplied to the fuel cell 24, and hot water and electric power are taken out by the fuel cell 24 with water supplied from the water tank 26 to the fuel cell 24 by the pump 27. . The extracted hot water is supplied to the fuel cell 21, and the extracted electric power is stored in the storage battery 25 and used as a power source for the electric heater 16, the pump 27, and the emergency shut-off valve 31. In some cases, the electric power stored in the storage battery 25 is supplied to the outside.

  Thus, in this embodiment, since the natural gas before decompression is heated using the energy extracted by the fuel cell 24 using the natural gas regulated to a constant pressure by the decompression valve 23 as the fuel, the decompression is performed. Regardless of the time change or daily change of the pressure of the previous natural gas, it is possible to stably heat the natural gas before decompression even during a power outage, and to perform a significant heating like when using a decompression turbine. Since it is not necessary to perform, it is possible to efficiently heat the natural gas before decompression, the natural gas can be regulated properly, and the natural gas can be supplied stably. In addition, since the fuel cell 24 that extracts energy based on a chemical reaction is used, there is little generation of large mechanical vibration and noise as in the case of using a decompression turbine or a heat pump, and a compact decompression facility can be obtained. it can.

  Further, at the start of operation when hot water having a sufficient temperature cannot be obtained from the fuel cell 24, the natural gas is heated using the electric heater 22 by the electric power taken out from the fuel cell 24 and stored in the storage battery 25. Natural gas can be stably heated from the start of operation.

  In this embodiment, the electric heater 22 is provided on the downstream side of the heat exchanger 21, but the electric heater 22 may be provided on the upstream side of the heat exchanger to heat the natural gas before decompression. In addition, the heat exchanger 21 and the electric heater 22 are provided in parallel, and immediately after the start of operation, the natural gas before being depressurized is heated through the path provided with the electric heater 22 and then supplied to the pressure reducing valve 23, and a certain time has elapsed. Then, the path may be switched to the path provided with the heat exchanger 21 to heat the natural gas before decompression and supply the decompression valve 23.

It is a flowchart which shows one Embodiment of this invention. It is explanatory drawing of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High pressure gas pressure reduction equipment 2 Natural gas supply line of upstream side 3 Natural gas supply line of downstream side 11-19 Path | route 21 Heat exchanger 22 Electric heater 23 Pressure reducing valve 24 Fuel cell 25 Storage battery 26 Water tank 27 Pump 31 Emergency cut-off valve 32 Filter 33 Ball valve 34a, 34b Pressure gauge 35a, 35b, 35c, 35d Thermometer

Claims (3)

  A high-pressure gas decompression facility that receives high-pressure natural gas from the upstream side, depressurizes it to a predetermined pressure and supplies it to the downstream side, a fuel cell for taking out hot water using the decompressed natural gas, and the fuel cell A heat exchanger that heat-exchanges the hot water taken out by the natural gas before decompression and heats the natural gas before decompression, and a decompression valve that decompresses the heated natural gas to a predetermined pressure. A high-pressure gas decompression facility comprising:   A high-pressure gas decompression facility that receives high-pressure natural gas from the upstream side, depressurizes it to a predetermined pressure and supplies it to the downstream side, a fuel cell for taking out electric power using the decompressed natural gas, and the fuel cell A high-pressure gas decompression comprising heating means for heating the natural gas before decompression using the electric power taken out by the power supply, and a decompression valve for decompressing the heated natural gas to a predetermined pressure Facility.   A high-pressure gas decompression facility that accepts high-pressure natural gas from the upstream side, depressurizes it to a predetermined pressure and supplies it to the downstream side, a fuel cell for taking out hot water and electric power using the decompressed natural gas, A heat exchanger for heating hot water extracted by the fuel cell and natural gas before decompression to heat the natural gas before decompression, and natural gas before decompression using the electric power extracted by the fuel cell A high-pressure gas decompression facility comprising heating means for heating the gas and a pressure reducing valve for reducing the heated natural gas to a predetermined pressure.

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