CN218119717U

CN218119717U - LNG gasification and cold energy power generation utilization system

Info

Publication number: CN218119717U
Application number: CN202222366610.6U
Authority: CN
Inventors: 王景甫; 王苡帆
Original assignee: Beijing University of Technology
Current assignee: Beijing University of Technology
Priority date: 2022-09-07
Filing date: 2022-09-07
Publication date: 2022-12-23
Anticipated expiration: 2032-09-07

Abstract

The utility model discloses a LNG gasification and cold energy electricity generation utilize system, this system comprises LNG gasification subsystem and LNG cold energy electricity generation subsystem. The LNG gasification subsystem mainly comprises an LNG primary gasifier and a LNG secondary gasifier. In the LNG primary vaporizer, the vaporizer is designed by adopting a sleeve, a spray pipe is adopted at the LNG side in the pipe, the LNG is sprayed in the sleeve, and the heat exchange between the LNG and a saturated organic working medium is strengthened; in the LNG secondary gasifier, fins are additionally arranged on the organic working medium side to strengthen the heat exchange between the organic working medium wet steam and the LNG in the pipe. Through the two-stage LNG vaporizer, the weak side of heat exchange is strengthened respectively, the cold energy of LNG is fully utilized, and the utilization rate of the cold energy and the heat exchange efficiency are improved. In the LNG cold energy power generation system, LNG cold energy is used as a cold source, seawater is used as a heat source, and an organic Rankine cycle power generation system is adopted for power generation. In order to better meet the requirement of gas utilization, a set of groove type solar heat collecting system is arranged at the tail end of the system.

Description

LNG gasification and cold energy power generation utilization system

Technical Field

The utility model relates to a LNG gasification and utilize LNG cold energy to carry out the new system that generates electricity.

Background

Liquefied natural gas (LNG for short) is a high-efficiency clean energy, and the quantity of imported LNG reaches thousands of tons every year in China. At the LNG receiving station, LNG need pressurize the gasification and get into the natural gas pipe network behind the normal atmospheric temperature gas, and in the LNG gasification, LNG will release a large amount of cold energy, with the reasonable recycle of cold energy, can improve the utilization efficiency of the energy. In large-scale offshore LNG receiving stations, organic Rankine cycle power generation is generally adopted, but the existing organic Rankine cycle power generation efficiency is low, and a large amount of LNG cold energy cannot be utilized, so that the improvement of the organic Rankine cycle power generation process and the improvement of the power generation efficiency are of great importance.

Disclosure of Invention

The utility model aims to overcome the problems of low heat exchange efficiency and low cold energy utilization rate of the LNG gasifier, and designs a novel LNG gasifier to improve the cold energy utilization rate of LNG; in order to overcome the problem of incomplete LNG gasification and meet different gas utilization requirements, a groove type solar heat collecting system is additionally arranged in the circulating process to sufficiently heat and gasify natural gas.

The technical scheme of the utility model is that: an LNG gasification and power generation device comprises a primary LNG gasifier and a secondary LNG gasifier; it is characterized by also comprising: the LNG gasification subsystem comprises an LNG storage tank, an LNG booster pump, a low-temperature medium channel of a primary LNG gasifier, a low-temperature medium channel of a secondary LNG gasifier, a first low-temperature medium channel of a seawater heat exchanger and a trough type solar heat collector channel which are connected in sequence; LNG enters the first-stage gasifier and the second-stage gasifier sequentially to exchange heat with the organic working medium after being pressurized by the LNG booster pump, then enters the seawater heat exchanger to exchange heat with seawater, and then enters the groove type solar heat collector to be heated. The LNG cold energy power generation subsystem comprises a high-temperature medium channel of a primary LNG vaporizer, a high-temperature medium channel of a secondary LNG vaporizer, an organic working medium circulating pump, a second low-temperature medium channel of a seawater heat exchanger and a turbine generator which are sequentially connected; the organic working medium exchanges heat with LNG through a primary gasifier and a secondary gasifier, is cooled and liquefied, is pressurized through an organic working medium circulating pump, exchanges heat with seawater through a seawater heat exchanger and is gasified into high-pressure steam, and the high-pressure steam enters a turbine to drive a generator to generate power.

The one-level gasifier structure comprises an external shell and an internal double-layer sleeve. The inner pipeline of the double-layer sleeve pipe in the double-layer sleeve pipe adopts a spraying pipeline, the inner diameter of the spraying pipeline is 10mm, and a plurality of spraying holes are uniformly distributed on the surface of the pipeline; the outer pipe of the double-layer sleeve adopts a pipeline with a petal-shaped cross section, wherein each petal-shaped pipeline adopts an arc with the diameter of 15mm and the angle of 45 degrees. One end of the double-layer sleeve is provided with an inner pipe which is open, and an outer pipe which is closed is an inlet of the pipeline; the outer pipe at the other end is opened, and the inner pipe is closed and is an outlet of the pipeline.

Second grade vaporizer structure comprises outside casing and inner tube, and the internal diameter of inner tube is 10mm. A plurality of annular ribs are uniformly and crossly arranged on the inner surface of the shell of the gasifier and the outer surface of the inner pipeline.

The left end and the right end of the shell of the primary gasifier and the secondary gasifier of the utility model are respectively provided with an LNG inlet and an LNG outlet; the upper side and the lower side of the shell are respectively provided with an inlet and an outlet of the organic working medium.

The utility model discloses used organic working medium is propane among the LNG cold energy power generation circulating channel.

The utility model discloses be provided with slot type solar energy collection system at circulation system's end, heat the natural gas after the gasification according to with the gas demand.

Compare with current LNG gasification and cold energy power generation system, the utility model discloses there is following advantage:

in the LNG heat exchanger, different types of heat exchangers are respectively designed and different heat exchange modes are adopted for enhanced heat exchange according to the states of propane and LNG at different stages, so that the heat exchange between the LNG and the organic working medium propane is enhanced, the cold energy of the LNG is fully utilized, the heat exchange efficiency is improved, and the utilization rate of the cold energy of the LNG is improved; the tail end of the LNG gasification system is additionally provided with the trough type solar heat collector, and LNG is completely gasified through the design.

Drawings

Fig. 1 shows a schematic diagram of an LNG gasification and cold energy power generation system in accordance with the present invention.

Fig. 2 shows a schematic structural diagram of the primary gasifier of the present invention.

Fig. 3 shows a schematic structural diagram of the second stage gasifier of the present invention.

Fig. 4 shows a cross-sectional view of the primary gasifier of the present invention.

Fig. 5 shows a schematic diagram of the internal piping structure of the primary gasifier of the present invention.

Fig. 6 shows the schematic diagram of the internal piping structure of the second stage gasifier of the present invention.

In the figure, 1, an LNG storage tank; 2. an LNG booster pump; 3. a primary LNG vaporizer; 4. a secondary LNG vaporizer; 5. an organic working medium circulating pump; 6. a seawater heat exchanger; 7. a turbine; 8. a trough solar collector; 9. a seawater storage tank; 10. a primary vaporizer LNG inlet; 11. an LNG outlet of the primary gasifier; 12. an organic working medium outlet of the primary gasifier; 13. an organic working medium outlet and inlet of the primary gasifier; 14. an LNG spray line; 15. a primary vaporizer LNG conduit; 16. a first-stage gasifier organic working medium pipeline; 17. a secondary vaporizer LNG inlet; 18. an LNG outlet of the secondary gasifier; 19. an organic working medium outlet of the secondary gasifier; 20. an organic working medium inlet of the secondary gasifier; 21. a secondary vaporizer LNG pipeline; 22. a secondary gasifier organic working medium pipeline; 23. an annular rib; 24. the secondary gasifier organic working medium pipeline internal fins; 25. and the LNG pipeline of the secondary gasifier is provided with external fins.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

As shown in fig. 1, the present embodiment provides an LNG gasification and cold energy power generation apparatus, which includes an LNG gasification apparatus and an LNG cold energy power generation apparatus. The LNG gasification device comprises an LNG storage tank 1, an LNG booster pump 2, a low-temperature medium channel of a primary LNG vaporizer, a low-temperature medium channel of a secondary LNG vaporizer, a seawater heat exchanger 6 and a trough type solar heat collector 8 which are sequentially connected. The LNG cold energy power generation device comprises a high-temperature medium channel of a primary LNG vaporizer, a high-temperature medium channel of a secondary LNG vaporizer, an intermediate medium circulating pump 5, a seawater heat exchanger 6 and a turbine 7.

The concrete work of this scheme utilization LNG cold energy power generation's device as follows:

LNG flows through an LNG booster pump from a storage tank through a pipeline, and after pressurization, the LNG flows into a primary LNG vaporizer and is sprayed in a petal-shaped pipeline to exchange heat with propane steam in a high-temperature pipeline, and the propane steam is changed into wet steam; the LNG after heat exchange continuously flows into a secondary LNG vaporizer, further exchanges heat with the propane wet steam, and the propane wet steam is completely liquefied; then the LNG flows into a seawater heat exchanger through a pipeline to exchange heat with seawater; LNG continuously flows into the groove type solar heat collector, the LNG is gasified, and then is output through a natural gas pipeline.

The liquefied propane is pressurized by a circulating pump and then flows into a seawater heat exchanger to exchange heat with seawater in a heat exchanger pipeline, propane liquid is gasified into propane steam and flows into a turbine to push blades to rotate so as to drive a generator to generate power, and the propane steam after acting enters an LNG vaporizer again so as to complete the power generation cycle.

As shown in fig. 5, the inner pipe of the primary LNG heat exchanger is an LNG flow pipe, the pipe is designed as a spray pipe, and LNG is sprayed on the petal-shaped casing pipe from the pipe to exchange heat with the organic working medium propane flowing in the outermost pipe.

As shown in fig. 6, the inner pipe of the secondary LNG heat exchanger is an LNG flow pipeline, fins are arranged outside the pipeline, the outer pipe is an organic working medium propane flow pipeline, and fins are also arranged on the inner side of the outer pipeline, so that fluid disturbance is enhanced, heat exchange of the organic working medium is enhanced, and heat transfer effect is improved.

The detailed description of the embodiments of the present invention has been provided, but the present invention is only the preferred embodiments of the present invention, and the present invention is not to be considered as limiting the scope of the present invention.

Claims

1. An LNG gasification and cold energy power generation utilization system comprises a primary LNG gasifier and a secondary LNG gasifier; it is characterized by also comprising:

the LNG gasification subsystem comprises an LNG storage tank, an LNG booster pump, a low-temperature medium channel of a primary LNG gasifier, a low-temperature medium channel of a secondary LNG gasifier and a first low-temperature medium channel of a seawater heat exchanger which are connected in sequence;

the LNG cold energy power generation subsystem comprises a high-temperature medium channel of a primary LNG vaporizer, a high-temperature medium channel of a secondary LNG vaporizer, an organic working medium circulating pump, a second low-temperature medium channel of a seawater heat exchanger and a turbine generator which are sequentially connected;

the primary gasifier structure consists of an external shell and an internal double-layer sleeve; the inner pipeline of the double-layer sleeve pipe in the double-layer sleeve pipe adopts a spraying pipeline, the inner diameter of the spraying pipeline is 10mm, and a plurality of spraying holes are uniformly distributed on the surface of the pipeline; the outer pipe of the double-layer sleeve adopts a pipeline with a petal-shaped cross section, wherein each petal-shaped pipeline adopts an arc with the diameter of 15mm and the angle of 45 degrees; one end of the double-layer sleeve is provided with an inner pipe which is open, and an outer pipe which is closed is an inlet of the pipeline; the outer pipe at the other end is opened, and the inner pipe is closed and is an outlet of the pipeline;

the secondary gasifier structure consists of an external shell and an internal pipeline, and the internal diameter of the internal pipeline is 10mm; a plurality of annular ribs are uniformly and crossly distributed on the inner surface of the shell of the gasifier and the outer surface of the internal pipeline;

the left end and the right end of the shell are respectively provided with an LNG inlet and an LNG outlet; the upper side and the lower side of the shell are respectively provided with an inlet and an outlet of the organic working medium.

2. The LNG gasification and cold energy power generation utilization system of claim 1, wherein the organic working medium used in the LNG cold energy power generation circulation channel is propane.

3. The LNG vaporization and cold energy power generation utilization system according to claim 1, wherein a trough type solar heat collection system is provided at an end of the circulation system.