CN216591044U

CN216591044U - Energy-saving processing system for evaporator of LNG receiving station

Info

Publication number: CN216591044U
Application number: CN202122442652.9U
Authority: CN
Inventors: 叶忠健
Original assignee: Yichang Medium Combustion City Gas Development Co ltd
Current assignee: Yichang Medium Combustion City Gas Development Co ltd
Priority date: 2021-10-11
Filing date: 2021-10-11
Publication date: 2022-05-24
Anticipated expiration: 2031-10-11

Abstract

LNG receiving station evaporimeter energy-conserving processing system, including the LNG pipe, LNG pipe both ends communicate user pipe network and LNG storage tank respectively, still include the heat exchanger, gas boiler, the gas holder, water tank and LNG pipe, heat exchanger shell side intercommunication is on the LNG pipe, be equipped with the water pump in the water tank, heat exchanger tube side both ends are respectively through inlet tube and wet return and boiler return mouth and water pump intercommunication, the boiler outlet passes through hot-water line intercommunication water tank upper end, the gas boiler air inlet passes through intake pipe intercommunication LNG pipe, the gas holder switch-on is on the LNG pipe, install first valve and relief pressure valve in the intake pipe between gas holder and gas boiler, install second valve and check valve in the intake pipe between gas holder and LNG pipe, the gas holder passes through BOG pipe and BOG air supply intercommunication, install compressor and third valve on the BOG pipe. The LNG vaporization system is used for solving the problems of uneven heating, higher energy consumption and unsafe existing in the existing LNG vaporization.

Description

Energy-saving processing system for evaporator of LNG receiving station

Technical Field

The utility model relates to an energy-saving processing system for a vaporizer of an LNG receiving station.

Background

The vaporizer is also called as a vaporizer, and is used for heating natural gas vaporized to a temperature of more than 10 ℃ from low-temperature LNG in a receiving station, and then sending the natural gas to a user pipe network, and many existing vaporizers use seawater as a heat source to vaporize the natural gas, for example, patent numbers "CN 104048161B, a Liquid Natural Gas (LNG) combined vaporizer", "CN 105509523B, and a heat pipe LNG vaporizer", and these vaporizers are suitable for coastal cities in south, but are not suitable for inland cities, and ordinary inland cities use air cooling to vaporize the natural gas, for example, patent numbers "CN 209540501U, an anti-freezing LNG vaporizer", which uses hot air to heat a vaporizing body, and this vaporizing method can achieve good vaporizing effect in summer, but natural gas close to a fan part of the vaporizing body can be vaporized well in winter, and the portion of the vaporizing body far away from the fan can still be frozen, heating is not uniform enough, and electric energy is wasted; there is also a way of passing through a water bath, such as "CN 213065530U," a temperature-regulated LNG water bath vaporizer, "and the way of heating water is by heating wires, which is very power-consuming and unsafe.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide an energy-saving processing system for an LNG receiving station evaporator, which is used for solving the problems of uneven heating, higher energy consumption and unsafety in the existing LNG evaporation and vaporization.

In order to solve the problems, the technical scheme of the utility model is as follows:

LNG receiving station evaporimeter energy-conserving processing system, including the LNG pipe, LNG pipe both ends communicate user pipe network and LNG storage tank respectively, still include the heat exchanger, gas boiler, the gas holder, water tank and LNG pipe, heat exchanger shell side intercommunication is on the LNG pipe, be equipped with the water pump in the water tank, heat exchanger tube side both ends are respectively through inlet tube and wet return and boiler return mouth and water pump intercommunication, the boiler outlet passes through hot-water line intercommunication water tank upper end, gas boiler air inlet passes through intake pipe intercommunication LNG pipe, the gas holder switch-on is in the intake pipe, install first valve and relief pressure valve in the intake pipe between gas holder and gas boiler, install second valve and check valve in the intake pipe between gas holder and LNG pipe, the gas holder passes through BOG pipe and BOG air supply intercommunication, install compressor and third valve on the BOG pipe.

Still include the bypass pipe, bypass pipe both ends and heat exchanger shell side both ends LNG pipe intercommunication, the switch-on has the finned plate vaporizer on the bypass pipe, installs the fourth valve on the bypass pipe, installs the fifth valve on fourth valve one side LNG pipe.

The LNG storage tank is characterized by further comprising a controller, a first temperature sensor, a pressure sensor arranged on the gas storage tank, and a second temperature sensor arranged on the LNG pipe, wherein the first temperature sensor is used for detecting the ambient temperature, the first temperature sensor, the second temperature sensor and the pressure sensor are connected with the input end of the controller, and the first valve, the second valve, the third valve, the fourth valve and the fifth valve are connected with the output end of the controller.

The utility model has the beneficial effects that:

1. adopt gas boiler to heat the back to water and send into the heat exchanger, the hot water in the heat exchanger heats the vaporization evaporation to the LNG of runoff, and gas boiler uses partly is the user pipe network of gas, and partly BOG of the recovery of LNG station then in addition, compares electrical heating, and not only the power consumption is lower, environmental protection and energy saving more moreover.

2. The finned plate vaporizer is bypassed on one side of the heat exchanger to share part of LNG vaporization amount, so that the consumption of hot water is reduced, the power of a boiler is reduced, the consumption of natural gas is reduced, and the energy consumption is further reduced.

Drawings

The utility model is further described below with reference to the accompanying drawings:

figure 1 is a schematic structural view of the present invention,

fig. 2 is a schematic diagram showing the connection relationship between the electric devices according to the present invention.

In the figure: the system comprises an LNG pipe 11, a water inlet pipe 12, a water return pipe 13, a hot water pipe 14, an air inlet pipe 15, a BOG pipe 16, a bypass pipe 17, a heat exchanger 20, a gas boiler 30, an air storage tank 40, a water tank 50, a first valve 61, a second valve 62, a third valve 63, a fourth valve 64, a fifth valve 65, a one-way valve 66, a pressure reducing valve 67, a compressor 70, a fin vaporizer 80, a water pump 90, a first temperature sensor 91, a second temperature sensor 92 and a pressure sensor 93.

Detailed Description

As shown in fig. 1 and 2, the LNG receiving station evaporator energy-saving processing system includes an LNG pipe 11, two ends of the LNG pipe 11 are respectively communicated with a user pipe network and an LNG storage tank, and further includes a heat exchanger 20, a gas boiler 30, a gas storage tank 40, a water tank 50 and an LNG pipe 11, a shell pass of the heat exchanger 20 is communicated with the LNG pipe 11, a water pump 90 is disposed in the water tank 50, two ends of a tube pass of the heat exchanger 20 are respectively communicated with a water return port of the boiler 30 and the water pump 90 through a water inlet tube 12 and a water return tube 13, a water outlet of the boiler 30 is communicated with an upper end of the water tank 50 through a hot water tube 14, a gas inlet of the gas boiler 30 is communicated with the LNG pipe 11 through a gas inlet tube 15, the gas storage tank 40 is communicated with a gas inlet tube 15, a first valve 61 and a pressure reducing valve 67 are disposed on the gas inlet tube 15 between the gas storage tank 40 and the gas boiler 30, a second valve 62 and a check valve 66 are disposed on the gas inlet tube 15 between the gas storage tank 40 and the LNG pipe 11, the check valve 66 prevents gas in the gas storage tank 40 from returning to the user pipe network, the gas tank 40 is connected to the BOG gas source through a BOG pipe 16, and a compressor 70 and a third valve 63 are provided in the BOG pipe 16.

The working process of the utility model is as follows:

1. starting the water pump 90 to circulate water through the tube side of the heat exchanger 20;

2. the compressor 70 starts, the BOG gas is sent into the gas storage tank 40, when the gas pressure in the gas storage tank 40 reaches 2-3 mpa, the air compressor is stopped, the third valve 63 is closed, then the first valve 61 is opened, the gas pressure in the gas storage tank 40 is reduced to 10kpa through the pressure reducing valve 67 and then sent into the gas boiler 30, meanwhile, the gas boiler 30 starts to heat water, when the water temperature reaches 70 ℃, the LNG is sent into the shell pass of the heat exchanger 20, the hot water is sent into a user pipe network after the LNG is evaporated and vaporized, and the gas pressure in the user pipe network is about 2-3 mpa.

3. The air pressure in the air tank 40 is gradually decreased with the continuous operation of the gas boiler 30, and when the air pressure in the air tank 40 is decreased to 1mpa, the second valve 62 is opened to allow the natural hot air in the user pipe network to enter the air tank 40, thereby continuously supplying the gas to the boiler 30.

4. When the pressure of the BOG in the LNG storage tank reaches 1-2 mpa, the second valve 62 is closed, the compressor 70 is started, the third valve 63 is opened, the BOG in the LNG storage tank is sent to the gas storage tank 40, and the gas boiler 30 preferentially uses the BOG.

5. And (4) repeatedly circulating according to the steps from 2 to 4.

The LNG heat exchanger further comprises a bypass pipe 17, two ends of the bypass pipe 17 are communicated with LNG pipes 11 at two ends of the shell side of the heat exchanger 20, the bypass pipe 17 is communicated with a finned vaporizer 80, a fourth valve 64 is installed on the bypass pipe 17, and a fifth valve 65 is installed on the LNG pipe 11 on one side of the fourth valve 64.

The structure of the fin-plate vaporizer 80 is the same as that of a CN210570170U LNG vaporizer with a large heat exchange area, and when the ambient temperature exceeds 25 ℃ in summer, the fifth valve 65 and the fourth valve 64 can be half opened and fully opened, so that LNG is mixed with the rest LNG vaporized by the heat exchanger 20 and output after passing through the fin-plate vaporizer 80; when the ambient temperature is lower than 0 ℃, the fifth valve 65 can be fully opened and the fourth valve 64 can be closed, and the LNG is completely vaporized by the heat exchanger; therefore, under the condition of high ambient temperature, the fin-plate vaporizer 80 shares part of LNG vaporization, the power of the gas boiler 30 is reduced, the gas consumption is reduced, and the energy consumption is further reduced.

The LNG vaporization control device comprises a controller, a first temperature sensor 91, install pressure sensor 93 on gas holder 40, install the second temperature sensor 92 on LNG pipe 11, first temperature sensor 91 is used for detecting ambient temperature, second temperature sensor 92 is used for detecting LNG vaporization temperature, first temperature sensor 91, second temperature sensor 92 and pressure sensor 93 connect the controller input, first valve 61, second valve 62, third valve 63, fourth valve 64, fifth valve 65 and compressor 70 connect the controller output, a boiler control cabinet and controller electric connection for controlling gas boiler, the controller can realize the automatic control to LNG vaporization, reduce workman intensity of labour, improve heat transfer accuracy.

The controller is a PLC (programmable logic controller), the first valve 61, the second valve 62 and the third valve 63 are all electric stop valves, the fourth valve 64 and the fifth valve 65 are PID (proportion integration differentiation) valves, the first temperature sensor 91 transmits detected ambient temperature data to the controller, the controller controls the opening degree of the fourth valve 64 and the opening degree of the fifth valve 65 according to the acquired temperature data, and when the ambient temperature rises, the opening degree of the fourth valve 64 is increased, the opening degree of the fifth valve 65 is reduced, and the power of the gas-fired boiler is reduced; when the ambient temperature is reduced, the opening degree of the fourth valve 64 is reduced, and the opening degree of the fifth valve 65 is increased, so that the LNG vaporization temperature is ensured to be above 10 ℃. The pressure sensor 93 transmits a pneumatic signal of the air tank 40 to the controller, and the controller controls the first valve 61, the second valve 62, the third valve 63 and the compressor 70 to be opened or closed according to the pneumatic signal.

Claims

The energy-saving processing system for the evaporator of the LNG receiving station comprises an LNG pipe (11), wherein two ends of the LNG pipe (11) are respectively communicated with a user pipe network and an LNG storage tank, and the energy-saving processing system is characterized in that: still include heat exchanger (20), gas boiler (30), gas holder (40), water tank (50) and LNG pipe (11), heat exchanger (20) shell side intercommunication is on LNG pipe (11), be equipped with water pump (90) in water tank (50), heat exchanger (20) tube side both ends respectively through inlet tube (12) and wet return (13) with boiler (30) return water mouth and water pump (90) intercommunication, boiler (30) outlet passes through hot-water line (14) intercommunication water tank (50) upper end, gas boiler (30) air inlet passes through intake pipe (15) intercommunication LNG pipe (11), gas holder (40) switch-on is on intake pipe (15), install first valve (61) and relief pressure valve (67) on intake pipe (15) between gas holder (40) and gas boiler (30), install second valve (62) and check valve (66) on intake pipe (15) between gas holder (40) and LNG pipe (11), the gas storage tank (40) is communicated with a BOG gas source through a BOG pipe (16), and a compressor (70) and a third valve (63) are installed on the BOG pipe (16).
2. The LNG receiving station vaporizer energy-saving processing system of claim 1, wherein: still include bypass pipe (17), bypass pipe (17) both ends and heat exchanger (20) shell side both ends LNG pipe (11) intercommunication, the switch-on has finned plate vaporizer (80) on bypass pipe (17), installs fourth valve (64) on bypass pipe (17), installs fifth valve (65) on fourth valve (64) one side LNG pipe (11).
3. The LNG receiving station vaporizer energy-saving processing system of claim 2, wherein: the LNG storage tank comprises an LNG pipe (11), and is characterized by further comprising a controller, a first temperature sensor (91), a pressure sensor (93) arranged on the gas storage tank (40), and a second temperature sensor (92) arranged on the LNG pipe (11), wherein the first temperature sensor (91) is used for detecting the ambient temperature, the first temperature sensor (91), the second temperature sensor (92) and the pressure sensor (93) are connected with the input end of the controller, and the first valve (61), the second valve (62), the third valve (63), the fourth valve (64), the fifth valve (65) and the compressor (70) are connected with the output end of the controller.