JP3026338B2 - Gas pipeline decompression equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decompression equipment installed in a pipeline of various gases transferred under high pressure to reduce the transfer gas to a predetermined pressure suitable for use at the end.

[0002]

2. Description of the Related Art In a gas pipeline for transferring various gases over a long distance, such as a pipeline for transferring natural gas, the pressure of a gas to be transferred is increased in order to reduce equipment costs by reducing the diameter of the pipe. In addition, a transfer method is widely used in which a high-pressure state is maintained and the pressure is reduced, while the pressure is reduced to a pressure suitable for use by a decompression facility provided at the end.

[0003] In many of these types of decompression equipment, the opening degree of a decompression valve provided in a pipeline is adjusted to provide a throttling resistance to a high-pressure transfer gas flowing through the inside of the decompression valve so that a predetermined decompression is performed. It is configured to obtain a low pressure suitable for Further, a preheating device is arranged upstream of the pressure reducing valve to preheat the transfer gas so that an appropriate temperature can be obtained after the pressure reduction accompanied by a temperature drop.

However, in such a decompression facility,
There is a problem that the retained pressure of the transfer gas is lost due to the pressure loss accompanying the passage of the pressure reducing valve, and most of the energy used for pressurizing and preheating the transfer gas is consumed unnecessarily.In recent years, for example, JP-A-3-112528, 1990
"CADDET (CENTER FOR THE ANALY
SIS AND DISEMINATION OF DEMONSTRATED ENERGY TECHNO
LOGIES); IEA / OECD; 5X.D00.NL.90.003 ”and the like, disposing a pressure reducing turbine at the end of a gas pipeline in place of the pressure reducing valve, and flowing a transfer gas through the pressure reducing turbine. As a result, decompression equipment capable of reducing the pressure to a desired pressure while recovering the retained energy of the transfer gas as the rotational energy of the decompression turbine is being adopted.

[0005]

In these decompression facilities, a generator is driven by the decompression turbine, and the power generated by the generator is used by other equipment in the facility. It is assumed that power is stored or sold or sold. On the other hand, even in these decompression facilities, preheating before supply to the decompression turbine is necessary in order to compensate for a temperature drop caused by decompression, and a preheating device is arranged upstream of the decompression turbine. Kaihei 3-112528
In the latter (CADDET), a boiler or a gas engine is operated using a transfer gas after pressure reduction as a fuel, and heat generated by these is used as a heat source. A preheating device configured to preheat the transfer gas by a heat exchanger is used.

[0006] As described above, in the conventional decompression equipment using the decompression turbine, a dedicated energy source is required for preheating the transfer gas before supply to the decompression turbine. In the former configuration, the power generated by the generator driven by the decompression turbine can be used as the energy source of the heater. In this case, the energy held by the transfer gas is first converted into rotational energy by the decompression turbine. And
Then, it is converted to electric energy by a generator, and further converted to heat energy by a heater and used for the preheating. By accumulating the conversion efficiencies at each conversion, the conversion efficiency to heat energy especially in the heater is reduced. Due to the low energy recovered by the decompression turbine is utilized with a significantly lower efficiency, essentially only providing supplementary energy for said preheating.

[0007] On the other hand, the latter configuration is based on the premise that the transfer gas is a flammable gas, and requires consumption of the transfer gas for preheating. Further, when the transfer gas is a non-flammable gas and an electric heating type boiler is used as the boiler, the energy held in the transfer gas is supplied to the preheating through a large amount of energy conversion as in the former configuration. As a result, the recovered energy has poor utilization efficiency, and it cannot be said that effective energy recovery is possible.

The present invention has been made in view of such circumstances, and it is possible to use the energy of a transfer gas recovered as rotational energy of a pressure reducing turbine with high efficiency for preheating the transfer gas. It is an object of the present invention to provide a gas pipeline decompression system capable of achieving a substantial increase in the substantial recovered energy excluding a preheating necessary portion.

[0009]

According to a first aspect of the present invention, there is provided a gas pipeline decompression system comprising a preheating device and a decompression turbine at an end of a pipeline for transferring a transfer gas.
In a gas pipeline decompression facility for supplying a transfer gas preheated through the preheating device to the decompression turbine and reducing the pressure to a predetermined pressure, and recovering retained energy of the transfer gas as rotational energy of the decompression turbine, the decompression turbine , And a heat pump driven by power supply from the generator and operating as a heat source of the preheating device.

[0010] In a gas pipeline decompression system according to a second aspect of the present invention, a preheating device and a decompression turbine are disposed at an end of a pipeline for transferring a transfer gas, and the transfer gas preheated through the preheating device is supplied to the gas decompression device. In a gas pipeline decompression facility for supplying a reduced pressure turbine to reduce the pressure to a predetermined pressure and recovering the retained energy of the transfer gas as rotational energy of the reduced pressure turbine, a compressor connected to the reduced pressure turbine; A heat pump included in a part thereof and operating as a heat source of the preheating device.

[0011]

According to the first aspect of the present invention, the generator is driven by the decompression turbine, the heat pump is driven by the generated power, and the transfer gas in the gas pipeline is preheated by the heat radiation of the heat pump. The heat radiation amount of the heat pump reaches several times the power required for driving, sufficient preheating is possible with a part of the generated power, and a sufficient amount of recovered energy is obtained as the remaining generated power.

In the second aspect of the present invention, the heat pump is directly driven by the rotary power obtained as the output of the pressure reducing turbine, and the energy retained in the transfer gas is directly recovered as the heat generated by the heat pump. The transfer gas is preheated by a part of the heat, and the remaining generated heat is used as recovered energy for other purposes.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing the embodiments. FIG. 1 is a block diagram schematically showing a configuration of a gas pipeline decompression facility according to a first invention of the present invention. In the figure, reference numeral 1 denotes a pipeline connected to the end of the gas pipeline. A pressure reducing turbine 2 is interposed in the middle of the pipeline 1, and a generator 3 is connected to an output end of the pressure reducing turbine 2. I have. In the drawings, the decompression turbine 2 and the generator 3 are illustrated as if they were directly connected, but the connection between the decompression turbine 2 and the generator 3 is generally performed via a reduction gear.

A high-pressure gas is transferred into the pipe 1 in a direction indicated by an open arrow in the drawing, and the transferred gas is supplied to the pressure-reducing turbine 2 and passes therethrough. During the flow, the pressure is reduced to a predetermined pressure in accordance with the purpose of use on the downstream side, and the retained energy of the transfer gas lost due to the reduced pressure is taken out to the output end of the pressure reducing turbine 2 as a rotational force, and The machine 3 is driven to rotate.

A preheating device 4 is provided in the middle of the pipeline 1 on the upstream side of the pressure reducing turbine 2. The preheating device 4 is for compensating for a temperature drop caused by the decompression in the decompression turbine 2 and ensuring an appropriate temperature for use on the downstream side of the decompression turbine 2, and includes a compressor 40, a condenser 41, The heat pump includes a liquid receiving tank 42, an expansion valve 43, and an evaporator 44.

As is well known, the heat pump comprises a compressor 40,
A refrigerant is sealed in a pipe that circulates through the condenser 41, the liquid receiving tank 42, the expansion valve 43, and the evaporator 44 in this order. The compressor 40 sucks the refrigerant in a vaporized state and compresses the refrigerant under an approximate adiabatic state. The refrigerant which has become high temperature and high pressure by this compression is introduced into the condenser 41, liquefied by heat radiation to the surrounding medium to be heated, stays in the liquid receiving tank 42, is throttled and expanded by the expansion valve 43, and The mixture is introduced into the evaporator 44 in a gas-liquid mixed state, and is evaporated and vaporized by endothermic heat from the periphery, and is sucked into the compressor 40 again.

As shown in the figure, the heat pump having the above-described operation includes the condenser 41 interposed in the middle of the pipe 1 and the condenser 41.
A heat exchanger for preheating the transfer gas inside the pipe line 1 by the heat radiation accompanying the condensation at 41 is constituted, while the driving motor 45 of the compressor 40 is supplied from the generator 3 on the output side of the pressure reducing turbine 2. , And is configured to be rotationally driven. Also evaporator
44 is in contact with low heat sources such as groundwater and air.

Before being introduced into the pressure reducing turbine 2, the transport gas inside the pipe 1 comes into contact with the heat pump as the preheating device 4, and at this time, heat radiation from the heat pump 4, specifically, the condenser 41 The heat pump absorbs the heat released from the heat source and is preheated. The heat pump replenishes the amount of heat lost by the heat release by absorbing heat from a low heat source when the evaporator 44 evaporates.

In the heat pump that operates as described above, by driving the compressor 40, the transfer gas is preheated by radiating heat from the condenser 41, and the motor for driving the compressor 40 provided as an input is provided. The ratio (coefficient of performance) between the output of the condenser 45 and the amount of heat radiation in the condenser 41, which is the final output, reaches 5 to 6 in theory. That is, the transfer gas in the pipe line 1 is preheated by the amount of heat corresponding to 5 to 6 times the driving power of the compressor 40.
The drive of 40 only requires an input of 5-6 times the amount of heat for the preheating. However, this result is based on a theoretical coefficient of performance, and an actual drive of the compressor 40 requires a little more input than the above input.

The transfer gas whose temperature has been increased by such preheating is supplied to the pressure reducing turbine 2 as described above, and the pressure is reduced to a predetermined pressure suitable for use and the temperature is lowered to a predetermined temperature. The retained energy of the gas is recovered as rotational power at the output end of the decompression turbine 2, and the generator 3 is driven by the rotational power, and the generated power is supplied to the drive motor 45 of the compressor 40. Therefore, even if the mechanical efficiency of the pressure reducing turbine 2, the power generation efficiency of the generator 3, and the motor efficiency of the drive motor 45 are taken into account, the preheating of the transfer gas can be covered by a part of the recovered energy by the pressure reducing turbine 2. As a result, the remaining power generated by the generator 3 can be used by other equipment in the facility, and can be stored or sold.

A temperature sensor 11, a pressure sensor 12, and a flow rate sensor 13 for detecting the temperature, pressure and flow rate of the internal transfer gas are provided upstream of the preheating device 4 in the pipe line 1.
In addition, a temperature sensor 14 for detecting the temperature of the internal transfer gas is attached to the downstream side of the decompression turbine 2, and the detection result is obtained based on a control interposed between the generator 3 and the driving motor 45. Provided to Part 6. The controller 6 may adjust the amount of power supplied from the generator 3 to the drive motor 45, increase or decrease the amount of refrigerant circulating in the heat pump, and control the degree of preheating of the transfer gas. The control operation is performed based on the detection result of each sensor.

FIG. 2 is a block diagram schematically showing a configuration of a gas pipeline decompression facility according to a second invention of the present invention. This decompression equipment is connected to the end of the gas pipeline, and the decompression turbine 2 is installed in the middle of the pipeline 1 in which high-pressure gas is transferred in the direction shown by the white arrow in the figure, similarly to the decompression equipment of the first invention. A preheating device 5 is provided on the upstream side of the pressure reducing turbine 2 for preheating the transfer gas in the pipeline 1 before supplying the gas to the pressure reducing turbine 2.

The preheating device 5 includes a compressor 50, a condenser 51,
It comprises a heat pump provided with a liquid receiving tank 52, an expansion valve 53 and an evaporator 54, and a heat exchanger 55 provided in the middle of the pipe 1. The compressor 50 of the heat pump is connected to the output end of the decompression turbine 2 unlike the decompression equipment of the first invention, and is directly operated by the rotational force taken out to the output end of the decompression turbine 2 as the transfer gas is depressurized. It is designed to be driven to rotate. In this case, as in the case of the first invention, the connection between the pressure reducing turbine 2 and the compressor 50 is generally performed through a speed reducer.

The condenser 51 of the heat pump is connected to a heat exchanger 55 in the middle of the pipe 1 through a hot water pipe 56 as shown in the figure. In the middle of the hot water pipe 56, a circulation pump 57 and a flow control valve 58 are interposed, and between the condenser 51 and the heat exchanger 55, the operation of the pump 57 causes Is circulated, and the circulating amount can be appropriately changed by adjusting the opening of the flow control valve 58. A water supply pipe 59 and a return pipe 60 are connected to the condenser 51 in parallel with the hot water pipe 56.

Compressor 50, condenser 51, liquid receiving tank 52, expansion valve 53
As described above, the heat pump including the evaporator 54 absorbs heat from a low heat source by evaporating the refrigerant in the evaporator 54, and releases the absorbed heat with the condensation in the condenser 51. By this heat radiation, the water circulating in the hot water pipe 56 and the water supplied from the water supply pipe 59 are heated. Then, the hot water in the hot water pipe 56 is introduced into the heat exchanger 55, acts to preheat the transfer gas by heat exchange with the transfer gas inside the pipe 1, and the water introduced from the water supply pipe 59 is Return pipe 60
And is used in various heat utilization facilities in a decompression facility such as a heat source for heating.

In the above configuration, the transfer gas in the pipeline 1 is preheated by using a heat pump, which has a high coefficient of performance, as a heat source, and the compressor 50 serving as an input end of the heat pump is provided with a pressure reducing turbine 2 Is directly connected to the output end of the decompression gas, and only the mechanical loss in the decompression turbine 2 is reduced, and the energy stored in the transfer gas is used for driving the heat pump. The preheating of the transfer gas can be covered by a part of the gas.

As in the case of the first invention, the pipe 1 has:
A temperature sensor 11 and a pressure sensor for detecting the temperature, pressure and flow rate of the internal transfer gas, respectively, on the upstream side of the preheating device 5.
A temperature sensor 14 for detecting the temperature of the internal transfer gas is mounted on the downstream side of the decompression turbine 2, and a detection sensor 12 is provided to the control unit 7.

The control unit 7 adjusts the opening of the flow control valve 58 provided in the middle of the hot water pipe 56 to increase or decrease the amount of hot water circulating in the heat exchanger 55, and A control operation for changing the degree of distribution to the exchanger 55 and realizing appropriate preheating of the transfer gas is performed. This operation is performed based on the detection results of the sensors.

In FIG. 2, the excess energy recovered from the decompression turbine 2 is used as the heat energy of the hot water taken out to the return pipe 60. It is also possible to connect a generator in series with the generator and use the surplus of recovered energy as electric energy generated by the generator.

In FIG. 1 showing the decompression equipment according to the first invention, the condenser 41 of the heat pump is also used as a heat exchanger. However, like the decompression equipment according to the second invention shown in FIG. It is also possible to adopt a configuration in which hot water is generated by the heat radiation of the heat exchanger 41 and a heat exchanger for performing heat exchange between the hot water and the transfer gas is provided.

[0031]

As described in detail above, in the gas pipeline decompression equipment according to the first aspect of the present invention, a generator is driven by a decompression turbine for depressurizing the transfer gas, and the generator is driven by the generated power of the generator. Since the transfer gas is preheated by the heat radiation of the heat pump having a high coefficient of performance, the retained energy of the transfer gas recovered as the rotational energy of the decompression turbine can be used with high efficiency for preheating the transfer gas, A substantial increase in the substantial recovered energy, excluding the need for this, is realized.

Further, in the gas pipeline decompression equipment according to the second invention of the present invention, in addition to the effect of the first invention, the heat pump is directly driven by the rotary power obtained as the output of the decompression turbine. The present invention has excellent effects, such as the energy stored in the gas can be used with higher efficiency, and the substantial recovered energy can be further increased.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically illustrating a configuration of a gas pipeline decompression facility according to a first invention of the present invention.

FIG. 2 is a block diagram schematically showing a configuration of a gas pipeline decompression facility according to a second invention of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipeline 2 Decompression turbine 3 Generator 4 Preheating device 5 Preheating device 6 Control part 7 Control part 40 Compressor 41 Condenser 45 Motor 50 Compressor 51 Condenser 55 Heat exchanger 56 Hot water pipe 58 Flow control valve

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoshi Akimoto 4-5-33 Kitahama, Chuo-ku, Osaka City, Osaka Prefecture Inside Sumitomo Metal Industries, Ltd. (72) Inventor Kazuo Yuzato 4-5-Kitahama, Chuo-ku, Osaka City, Osaka Prefecture No. 33 Sumitomo Metal Industries, Ltd. (56) References JP-A-4-121573 (JP, A) JP-A-56-94167 (JP, A) JP-A-3-112528 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F02C 1/00 F17D 1/075 F25B 27/00

Claims (2)

(57) [Claims] 1. A preheating device and a decompression turbine are arranged in a pipeline for transferring a high-pressure gas, and a transfer gas preheated through the preheating device is supplied to the decompression turbine to reduce the pressure to a predetermined pressure and to reduce the transfer gas. In a gas pipeline decompression facility for recovering the energy held by the decompression turbine as rotational energy, a generator connected to the decompression turbine, and a heat pump driven by power supply from the generator and operating as a heat source of the preheating device A pressure reducing equipment for a gas pipeline, comprising: 2. A preheating device and a decompression turbine are provided in a pipeline for transferring a transfer gas, and the transfer gas preheated through the preheating device is supplied to the decompression turbine to reduce the pressure to a predetermined pressure, and the transfer gas is reduced. In a gas pipeline decompression facility for recovering the retained energy as rotational energy of the decompression turbine, a compressor connected to the decompression turbine, and a heat pump including the compressor as a part and operating as a heat source of the preheating device A pressure reducing equipment for a gas pipeline, comprising: