CN111980767A

CN111980767A - Supercritical low-temperature working medium cylinder body shaft seal gas turbine equipment and use method

Info

Publication number: CN111980767A
Application number: CN201910426871.2A
Authority: CN
Inventors: 翁志远
Original assignee: Beijing Hongyuan Baiside Technology Co ltd
Current assignee: Beijing Hongyuan Baiside Technology Co ltd
Priority date: 2019-05-21
Filing date: 2019-05-21
Publication date: 2020-11-24

Abstract

The embodiment of the invention provides a supercritical low-temperature working medium cylinder body shaft seal gas turbine device and a using method thereof, belonging to a gas turbine for low-temperature working medium; the temperature of the gas input by the main steam pipeline of the gas turbine is obviously higher than the critical temperature of the low-temperature power generation working medium; the temperature of the exhaust steam output by the exhaust pipeline of the gas turbine reaches the critical temperature of the low-temperature power generation working medium; the pressure of the gas input by the main steam pipeline of the gas turbine is obviously higher than the critical pressure of the low-temperature power generation working medium; the exhaust steam pressure output by the exhaust pipeline of the gas turbine reaches the critical pressure of the low-temperature power generation working medium; the embodiment also provides a shaft seal technology for sealing the shaft end by adopting a highly airtight structure of a gas turbine cylinder body, so as to solve the problem of leakage at two ends of a rotating shaft of a rotating machine such as a gas turbine or an expander and the like, in particular to a low-temperature working medium with high cost; the gas turbine has the advantages of low working medium temperature, compact structure, small volume, high efficiency, low cost, large torque force and the like.

Description

Supercritical low-temperature working medium cylinder body shaft seal gas turbine equipment and use method

Technical Field

The invention provides supercritical low-temperature working medium cylinder body shaft seal gas turbine equipment and a using method thereof, belonging to the technical field related to gas turbine machinery. The gas turbine includes, but is not limited to, gas turbines, pneumatic turbines, gas turboexpanders, gas screw expanders, and similar gas turbomachinery devices; besides the gas turbine, other gas turbine mechanical equipment is generally a small gas turbine, the cost is relatively high, and the number of the gas turbine mechanical equipment in practical application is relatively small; the gas turbine can be large-sized and can also be made into small-sized equipment, and is more popular in application; therefore, the embodiment of the invention mainly describes a low-temperature working medium gas turbine device, and other gas turbine devices are the same.

Background

In 1882, the first single-stage impulse turbine was designed and manufactured by the swedish engineer laval, and the turbine is a rotating machine which takes steam as power and converts the heat energy of the steam into mechanical work, and is the most widely applied prime mover in modern thermal power plants. The steam turbine has the advantages of large single machine power, high efficiency, long service life and the like, and is widely applied to power stations, ship navigation and large-scale industry.

In order to improve the power and the efficiency of steam turbine equipment, the improvement is continuously carried out for more than 100 years, the air inlet temperature and the air inlet pressure are continuously improved, the power of the steam turbine reaches 1200MW at most from a low-pressure steam turbine to a high-pressure steam turbine and then from a subcritical steam turbine to a supercritical steam turbine, the air inlet temperature reaches 650 ℃, and the pressure reaches 25 MPa; the exhaust temperature of the low pressure cylinder of the straight condensing steam turbine is as low as 30-45 ℃, the exhaust pressure is as low as 10-13kPa, and people can obtain the maximum enthalpy difference and power generation output by continuously increasing the inlet temperature and pressure of the steam turbine and reducing the exhaust temperature and pressure of the steam turbine as far as possible.

For example: the inlet steam of a certain high-pressure turbine contains about 3433kJ/kg of heat, only about 837kJ/kg of the heat is used for doing work, the condensed water contains about 126kJ/kg of heat, and about 2240kJ latent heat energy per kg of water is taken away by cooling water of a cooling system; this is a very significant loss and waste.

For low-temperature waste heat power generation, an organic working medium ORC Rankine cycle with the boiling point temperature of about 15 ℃ is also used, and hot water power generation above 80 ℃ can be realized; for a low-temperature power generation working medium with the boiling point temperature lower than 0 ℃ under the standard atmospheric pressure, the low-temperature power generation working medium is still in a research stage at home and abroad, and for technicians doing power generation work, the storage of the low-temperature power generation working medium is a difficult point, the boiling point of the extremely low-temperature power generation working medium is far lower than the environmental temperature, a low-temperature meson in equipment can be gasified when placed in the environment, and high-pressure gas formed cannot be reused and used for power generation; in addition, the biggest difficulty is that the low-temperature exhaust steam is reduced into liquid after the gas turbine does work, which is the biggest pain point.

In addition, the cylinder body of the steam turbine or the expander is still, the rotating speed of the rotor of the steam turbine or the rotor of the expander is very high, shaft sealing needs to be carried out between the rotating shaft rotating at high speed and the stationary cylinder body, otherwise, high-pressure gas input by the steam turbine leaks along the rotating shaft of the steam turbine, and the leakage pressure is very high. The steam turbine needs a shaft seal system, and the traditional steam turbine needs a tooth-shaped steam seal, a Braiden steam seal, a honeycomb steam seal, a brush steam seal, a flexible tooth steam seal and an elastic tooth steam seal; although the high-pressure air inlet end is provided with the shaft seal, the leakage of steam through the shaft seal cannot be avoided; the leakage rate of a large turbine can reach more than 10 tons per hour. Especially, the low-temperature organic working medium has high cost, so the shaft seal leakage cost is also quite high.

In addition, the traditional steam turbine adopts steam as a power generation working medium, high-pressure steam drives an impeller and a rotor of the steam turbine to rotate at a high speed through a nozzle, and mechanical energy is output or a generator is driven to rotate at a high speed to output electric energy; the low-temperature power generation mesons such as high-pressure carbon dioxide, high-pressure nitrogen, high-pressure air and the like enter the input end of the gas turbine, the impeller on the rotor of the gas turbine is blown through the nozzle, the impeller and the rotor of the gas turbine can be driven to rotate at high speed, the nozzle and the impeller of the gas turbine do not distinguish whether the input is high-pressure steam, high-pressure carbon dioxide gas, high-pressure air and high-pressure nitrogen, and the impeller of the gas turbine can rotate as long as the high-pressure gas drives the nozzle and the impeller; the same is true of the expander.

The same applies to other gas turbine mechanical devices, such as pneumatic machines, gas turbo expanders, single screw expanders, twin screw expanders, etc., which are generally applied to small-sized power generation devices, and the specific body structure of the gas turbine mechanical device is slightly different from that of a gas turbine, but basically the same and the same, and the rotors of the gas turbine and the expander rotate at high speed regardless of the gas input as long as the gas input is high-pressure gas.

It should be noted that, the conventional steam turbine and expander adopt common temperature or high temperature resistant steel, after the low temperature working medium supercritical steam turbine or expander does work, the temperature of the output exhaust steam is reduced to below zero (such as high pressure nitrogen, after the gas turbine does work, the temperature of the output exhaust steam is probably lower than minus 100 ℃), some steel of the common steam turbine is not low temperature resistant, embrittlement and cracking are probably occurred, obviously, this is not allowable, the solution is to adopt low temperature resistant materials, including but not limited to austenite low temperature steel and ferrite low temperature steel, select low temperature resistant materials and adjust according to the characteristics of the materials at low temperature.

The same as the low-temperature working medium supercritical gas turbine, the tail of the original equipment needs to be cut off, and only the part higher than the critical temperature is reserved for the gas turbine equipment such as the low-temperature working medium supercritical expander, the pneumatic machine, the screw expander and the like, so that the equipment volume is smaller and the driving force is strong; for the embodiment of the invention, the modification method and the use method are the same as those of the gas turbine;

compared with an organic working medium ORC Rankine cycle with the boiling point temperature of about 15 ℃, the low-temperature working medium supercritical gas turbine provided by the embodiment of the invention adopts lower-temperature power generation working media such as carbon dioxide with lower boiling point, liquid air, liquid nitrogen and the like, and can realize waste heat power generation at lower temperature (as low as 10 ℃); meanwhile, the cost of CO2, liquid air and liquid nitrogen per ton is only about hundreds of RMB, and is much lower than the cost of about 10 ten thousand organic working media. In order to solve the problems, the applicant continuously researches and explores for over twenty years, and finally finds a high-efficiency low-cost low-temperature working medium condensation technology and a new technology for preventing shaft seal leakage of a low-temperature working medium gas turbine or an expander.

Disclosure of Invention

The storage problem of extremely low-temperature liquid, including the storage of liquid carbon dioxide, liquid methane LNG, liquid nitrogen, liquid air, even liquid hydrogen and liquid helium, can be well solved by adopting a low-temperature liquid storage tank and a vacuum technology, which are mature technologies.

The invention aims to provide a low-temperature working medium supercritical gas turbine and a using method thereof, and the applicant researches and discovers that the last-stage blade and the next-last-stage blade of the gas turbine are simplified and optimized; the temperature of the exhaust steam discharged from the output end of the low-temperature working medium supercritical gas turbine reaches the critical temperature of the low-temperature power generation working medium; the pressure of the exhaust steam reaches the critical pressure of the low-temperature power generation working medium; the difference between the gas phase and the liquid phase disappears (latent heat of 0). Compared with the traditional steam turbine equipment, the volume is simplified, the probability of flutter fracture caused by overlarge traditional steam turbine blades is reduced, the efficiency and the reliability of the steam turbine equipment are improved, and the cost of the steam turbine can be reduced. Through the synergistic effect of the gas turbine equipment, the exhaust steam heat regenerator and the like, a high-efficiency power generation system is realized, the power generation efficiency is improved, and meanwhile, the gas turbine equipment cost and the power station investment cost can be reduced.

The embodiment of the invention is realized as follows:

in a first aspect, an embodiment of the present invention provides a supercritical low-temperature working medium cylinder body shaft seal gas turbine device and a use method thereof, wherein a working medium input by a main steam pipe of the low-temperature working medium supercritical gas turbine device is a low-temperature working medium with a boiling point temperature lower than zero degrees centigrade under a standard atmospheric pressure; the high-pressure gas working medium comprises any one or a plurality of combinations of carbon dioxide, ammonia gas, methane, ethane, nitrogen, air, oxygen, argon, hydrogen and helium;

the temperature of high-pressure gas input by a main steam pipe of the low-temperature working medium supercritical gas turbine is obviously higher than the critical temperature of the low-temperature working medium; the temperature of the exhaust steam discharged by the exhaust pipeline of the low-temperature working medium supercritical gas turbine reaches the critical temperature of the low-temperature working medium;

the pressure of high-pressure gas input by a main steam pipe of the low-temperature working medium supercritical gas turbine is obviously higher than the critical pressure of the low-temperature working medium; the exhaust steam pressure discharged by the exhaust pipeline of the low-temperature working medium supercritical gas turbine reaches the critical pressure of the low-temperature working medium;

notably, the temperature of the exhaust steam output by the exhaust pipeline of the low-temperature working medium supercritical gas turbine or the expander also comprises the temperature near the critical temperature point; the critical temperature is extremely accurate data, which cannot be actually achieved, and therefore, the temperature near the critical temperature point is required to be included;

Further, the temperature of the exhaust steam output by the low-temperature working medium supercritical gas turbine exhaust pipeline reaches the critical temperature of the low-temperature power generation working medium; the reaching includes exceeding the critical temperature in addition to the temperature near the critical temperature point; the characteristics of different low-temperature working media are different, the difference between the critical temperature and the standard boiling point temperature of hydrogen and helium is not large, and the critical pressure is small, under the condition, the exhaust steam temperature output by the exhaust pipeline of the low-temperature working medium supercritical gas turbine or the expansion machine can easily reach or even exceed the critical temperature, and even if the quantity exceeding the critical temperature is large, the reaching range is included;

the gas pressure input by the main steam pipeline of the low-temperature working medium supercritical turbine is required to be obviously higher than the critical pressure of the low-temperature power generation working medium; the exhaust steam pressure output by the exhaust pipeline of the low-temperature working medium supercritical gas turbine reaches or approaches the critical pressure of the low-temperature power generation working medium;

the exhaust steam pressure output by the low-temperature working medium supercritical gas turbine or the expander exhaust pipeline reaches or approaches the critical pressure of the low-temperature power generation working medium; pressures near critical temperature points are also included; the critical pressure is extremely accurate data, and cannot be actually made accurate, so that a pressure range near the critical pressure point needs to be included;

Because the temperature and the pressure of the gas input by the main steam pipeline of the low-temperature working medium gas turbine are obviously higher than the critical temperature and the critical pressure of the low-temperature power generation working medium, the low-temperature working medium gas turbine is called as a low-temperature working medium supercritical gas turbine;

the structure of the low-temperature working medium supercritical gas turbine equipment needs to meet the physical characteristics of density, components, temperature and pressure of a low-temperature power generation working medium;

the low-temperature parts of the low-temperature working medium supercritical gas turbine need to be made of low-temperature resistant materials, including but not limited to austenite low-temperature steel and ferrite low-temperature steel;

the low temperature and the normal temperature are different, and some normal temperature or high temperature steel is only suitable for the normal temperature and high temperature fields, but after being applied to the low temperature field, the possibility of becoming brittle or even cracking can occur, which is absolutely not allowable in the practical application condition; low temperature resistant materials must be selected to solve this problem;

preferably, a high-efficiency heat insulation material is arranged outside the equipment of the low-temperature working medium supercritical gas turbine or the expansion machine; including but not limited to foam, aerogel, vacuum insulation, fibrous materials, glass wool, high silica wool; the exhaust steam of the low-temperature working medium gas turbine is lower than the environment and needs to be kept at low temperature.

In a second aspect, the low-temperature working medium supercritical gas turbine belongs to a rotary power machine which converts high-temperature and high-pressure gas energy into mechanical work, and is also called as a gas turbine, and the gas turbine includes but is not limited to a gas turbine, a pneumatic machine, a gas screw expander and a gas turbine expander;

the structure of the gas turbine or the low-temperature working medium gas turbine equipment needs to meet the physical characteristics of the density, the composition, the temperature and the pressure of the low-temperature power generation working medium;

the gas turbine or the low-temperature working medium gas turbine equipment and low-temperature parts need to adopt low-temperature resistant materials, including but not limited to austenite low-temperature steel and ferrite low-temperature steel;

the high-efficiency heat insulation material is arranged outside the gas turbine or the low-temperature working medium gas turbine; including but not limited to foam, vacuum insulation, fibrous materials, glass wool;

the traditional gas turbine adopts steam as a working medium, high-pressure steam passes through a nozzle to drive a turbine impeller and a rotor to rotate at a high speed, gases such as high-pressure carbon dioxide, high-pressure nitrogen, high-pressure air and the like blow the turbine rotor impeller through the nozzle, and the turbine impeller rotor can also be driven to rotate, and the turbine nozzle and the turbine impeller do not distinguish whether the input is the high-pressure steam, the high-pressure carbon dioxide, the high-pressure air or the high-pressure nitrogen; the impeller of the gas turbine is rotated as long as it is driven by high-pressure fluid; the gas turbine mechanical equipment, such as a pneumatic machine, a gas turbine expander, a single-screw expander, a double-screw expander and the like, is also the same, and as long as high-pressure gas is input, regardless of the gas of the turbine, the rotor of the gas turbine or the expander rotates at a high speed;

The traditional existing pneumatic machine, single-screw expander, double-screw expander, gas turbine expander and other equipment are slightly different from a steam turbine in the body structure, but all belong to gas turbine equipment, and basically all belong to small-sized gas turbines (only the steam turbine can be large or small, and the application is the most extensive), but all traditional equipment are generally applied to normal-temperature working media, such as normal-temperature high-pressure air, medium-temperature high-temperature water vapor or organic power generation working media of organic Rankine cycle, but the application in the low-temperature field is generally not considered. The low temperature and the normal temperature are different, and some normal temperature or high temperature steel is only suitable for the normal temperature and high temperature fields, but after the steel is applied to the low temperature field, the possibility of becoming brittle or even cracking can occur, which is absolutely not allowable in the practical application situation; low temperature resistant materials must be selected to solve this problem, including but not limited to austenitic low temperature steels, ferritic low temperature steels;

in addition, the tail part of the original equipment of the traditional gas turbine equipment needs to be completely removed, and only the part above the critical temperature of the power generation working medium is reserved; the temperature and the pressure of high-pressure gas input by the low-temperature working medium gas turbine equipment are both required to be obviously higher than the critical temperature of a low-temperature power generation working medium; the temperature of the exhaust steam discharged from the output end of the low-temperature working medium gas turbine equipment reaches the critical temperature of the low-temperature working medium;

For the embodiment of the invention, the modification method is the same as that of the gas turbine, the equipment volume is smaller, and the driving is strong; the gas turbine can be large or small, the universality is higher, the technology is mature, the cost is lower, the quantity of other gas turbine equipment in the market is less, the embodiment of the invention mainly describes the gas turbine, and other equipment are the same and are not repeated;

the low-temperature working medium expander, the pneumatic machine and the low-temperature working medium supercritical gas turbine belong to gas turbine machinery, and only the structure of the equipment body is slightly different; in the embodiment of the invention, the low-temperature working medium expander, the input end and the output end of the pneumatic machine, the pipeline connecting method, the using method and the parameters are completely the same as those of the low-temperature working medium supercritical gas turbine, so that the low-temperature working medium supercritical gas turbine also belongs to the scope provided by the embodiment of the invention.

In a third aspect, an embodiment of the present invention further provides a shaft seal system adopting a highly sealed structure of a cylinder body of a gas turbine or an expander, where the low-temperature working medium supercritical gas turbine or expander is composed of a stationary part and a rotating part; the gas turbine or expander cylinder body shaft seal system comprises an input end shaft seal system and an output end shaft seal system;

The input end shaft seal system of the gas turbine comprises an input end cylinder body, an input end bearing, a bearing seat, an input end rotating shaft and a main steam pipeline; the input end bearing and the bearing seat comprise a support bearing and a thrust bearing;

a heat insulation shell is arranged outside the input end bearing and the bearing seat; the heat insulation shell is divided into an upper heat insulation shell and a lower heat insulation shell; the lower heat insulation shell is arranged in a lower cylinder at the position of the input end bearing and the bearing seat and is tightly combined with the lower cylinder of the gas turbine; the input end bearing and the bearing seat are arranged in a lower heat insulation shell in a lower cylinder of the gas turbine;

further, the lower heat insulation shell and the upper heat insulation shell are provided with flanges, and the lower heat insulation shell and the inner cavity of the upper heat insulation shell form a closed heat insulation space through the fastening of the flanges and bolts; the input end rotating shaft, the input end bearing, the bearing seat and lubricating oil are sealed in a heat insulation space formed by the heat insulation shell;

furthermore, the heat insulation shell wraps the contact position of the input end rotating shaft, a heat insulation shell seal is further arranged, and bearing lubricating oil in the heat insulation shell is prevented from leaking outwards from the heat insulation shell seal by the heat insulation shell seal.

In a fourth aspect, further, the upper heat-insulating shell and the lower heat-insulating shell of the heat-insulating shell are fastened through the flange and the bolt, a closed heat-insulating space is formed inside the upper heat-insulating shell, and a lubricating oil injection hole is formed in the top of the upper heat-insulating shell, so that lubricating oil is injected into the heat-insulating space between the bearing and the bearing seat;

the heat insulation shell also comprises a lubricating oil output pipeline, a lubricating oil filter, a lubricating oil cooler and a lubricating oil pump which are connected with the heat insulation shell; the low-temperature high-pressure lubricating oil output by the lubricating oil pump is conveyed to the bearing and the bearing seat in the heat insulation shell through a lubricating oil input pipeline; clean low-temperature lubricating oil is provided for the bearing and the bearing seat; high-temperature and dirty lubricating oil in the heat insulation shell is output through a lubricating oil output pipeline, conveyed to a lubricating oil filter and a lubricating oil cooler for cooling, pressurized by a lubricating oil pump and conveyed to the bearing to form circulation;

the lubricant filter, the lubricant cooler, and the lubricant pump are disposed outside a cylinder block of the gas turbine; or the lubricating oil cooling device is arranged in the cylinder body of the gas turbine, and when the lubricating oil cooling device is arranged in the cylinder body, a heat exchange pipeline is required to exchange heat with the outside so as to ensure the temperature of the lubricating oil to be constant;

Preferably, a lubricating oil temperature probe, a lubricating oil pressure probe, a lubricating oil quantity probe, and a pressure probe inside the gas turbine cylinder are further provided inside or outside the cylinder of the gas turbine equipment;

preferably, a shaft seal is further arranged between the main steam pipeline of the gas turbine and the heat insulation shell at the input end; preferably, an input end reserved space or a pipeline is further arranged between the heat insulation shell and the main steam pipeline, the input end reserved space or the pipeline is arranged in the lower cylinder, lubricating oil leaked from the sealing position of the heat insulation shell is stored, and the leaked dirty lubricating oil is discharged through a first pipeline valve.

In a fifth aspect, further, the output end of the gas turbine comprises a gas turbine exhaust pipeline, an output end cylinder, an output end bearing and bearing seat, a coupling and a generator; the gas turbine hides an output end bearing, a bearing seat, a coupler and a generator in an output end cylinder body of the gas turbine; the output terminal of the generator is arranged on the cylinder body of the gas turbine, and the sealing performance of the gas turbine cannot be influenced;

preferably, the gas turbine input end and the gas turbine output end are hidden in the gas turbine cylinder, and the high-tightness structure of the gas turbine cylinder is used for shaft sealing at two ends of the rotating shaft, so that low-temperature working medium is prevented from leaking from the shaft sealing at two ends of the rotating shaft of the gas turbine.

In a sixth aspect, the embodiment provides a method for using a low-temperature working medium supercritical gas turbine, which includes a low-temperature liquid storage tank, a low-temperature liquid pump, a low-temperature pipeline of an exhaust steam heat regenerator, a main heat exchanger, a low-temperature working medium supercritical gas turbine, and a high-temperature pipeline of the exhaust steam heat regenerator, which are sequentially communicated; the outlet of the high-temperature pipeline of the exhaust steam heat regenerator is connected with the inlet of the low-temperature liquid storage tank to form circulation;

the low-temperature liquid storage tank is provided with a pressure limiting valve safety valve protection device and a pressure container for storing a low-temperature working medium with high-efficiency heat preservation and heat insulation; the stored working medium is a low-temperature liquid power generation working medium with the boiling point temperature lower than zero degree centigrade under the standard atmospheric pressure;

the low-temperature liquid pump is a driving device for improving the pressure of the low-temperature liquid power generation working medium; the low-temperature liquid pump is arranged between the low-temperature liquid storage tank and the low-temperature pipeline of the exhaust steam heat regenerator;

the low-temperature pipeline of the exhaust steam heat regenerator is arranged between the low-temperature liquid pump and the main heat exchanger; the exhaust steam heat regenerator high-temperature pipeline is arranged between the outlet of the low-temperature working medium supercritical gas turbine exhaust pipeline and the low-temperature liquid storage tank; the low-temperature pipeline of the exhaust steam heat regenerator and the high-temperature pipeline of the exhaust steam heat regenerator exchange heat fully to form an exhaust steam heat regenerator with high-efficiency heat exchange; the exhaust steam heat regenerator is independently arranged or combined with the low-temperature working medium supercritical gas turbine;

The main heat exchanger is arranged between the low-temperature pipeline of the exhaust steam heat regenerator and the low-temperature working medium supercritical gas turbine; the main heat exchanger is a main device for exchanging heat with a heat source;

the main heat exchanger is divided into a low-temperature main heat exchanger and/or a high-temperature main heat exchanger; the low-temperature main heat exchanger comprises any one or more of a hot water heat exchanger, a condenser, a cooler, an air duct heat exchanger, an air heat exchanger, an equipment cooler, a geothermal heat exchanger and an industrial waste gas and waste liquid heat exchanger; the high-temperature main heat exchanger comprises any one or more of a boiler, a waste heat boiler and a medium-high temperature heat exchange device;

the inlet of the low-temperature working medium supercritical gas turbine is connected with the outlet of the main heat exchanger, and the outlet of the exhaust pipeline of the low-temperature working medium supercritical gas turbine is connected with the inlet of the high-temperature pipeline of the exhaust steam heat regenerator;

the temperature of high-pressure gas input by a main steam pipe of the low-temperature working medium supercritical gas turbine is obviously higher than the critical temperature of the low-temperature working medium; the temperature of the dead steam discharged by the exhaust pipeline of the low-temperature working medium supercritical gas turbine reaches or approaches to the critical temperature of the low-temperature working medium;

the low-temperature power generation working medium stored in the low-temperature liquid storage tank is used for increasing the pressure through the low-temperature liquid pump; the high-temperature gas flows through a low-temperature pipeline of the exhaust steam heat regenerator, is conveyed to the main heat exchanger to absorb external heat energy, expands rapidly in volume, forms high-temperature and high-pressure gas, and is conveyed to the low-temperature working medium supercritical gas turbine to drive the low-temperature working medium supercritical gas turbine to rotate at a high speed to output mechanical energy outwards or drive a generator to rotate at a high speed to output electric energy outwards.

In the seventh aspect, a throttle valve or an expansion machine is further included, and the throttle valve is arranged between the outlet of the high-temperature pipeline of the dead steam regenerator and the inlet of the low-temperature liquid storage tank;

the throttle valve is a throttling and pressure reducing device, and the throttling and pressure reducing device comprises but is not limited to a throttle valve, a stop valve and an expansion valve;

preferably, the system also comprises an expander or a turbine, wherein the expander or the turbine is arranged between the outlet of the high-temperature pipeline of the dead steam regenerator and the inlet of the low-temperature liquid storage tank;

the expander is a throttling and pressure reducing device, the expander comprises a turbine expander and a screw expander, the inlet of the expander is high-pressure, the outlet of the expander is low-pressure, and the expander rotates at a high speed to output mechanical energy or drives a generator to output electric energy;

the expansion machine consumes the internal energy of the high-pressure fluid to do work outwards while realizing throttling and pressure reduction, and realizes deeper refrigeration of the high-pressure fluid flowing through the expansion machine and returns the lower-temperature low-temperature working medium liquid to the low-temperature liquid storage tank for storage and standby application while doing work outwards;

the expansion machine is independently arranged, all high-pressure fluid directly enters the expansion machine to do work, the high-pressure fluid realizes throttling and pressure reduction through the expansion machine, internal energy of the high-pressure gas is consumed to do work outwards and realize deep cooling, and the dead steam liquid returns to the low-temperature liquid storage tank to be stored for later use; meanwhile, mechanical energy is output or the generator is driven to rotate to output electric energy;

Preferably, the expander is provided simultaneously with the throttle valve; the expansion machine and the throttle valve are in parallel connection and are jointly arranged between the outlet of the high-temperature pipeline of the dead steam heat regenerator and the inlet of the low-temperature liquid storage tank;

further, when the high-pressure exhaust steam output by the high-temperature pipeline outlet of the exhaust steam heat regenerator is in a gas-liquid mixed state, preferably, the high-pressure liquid is throttled and depressurized by the throttle valve and then returns to the low-temperature liquid storage tank for storage; throttling and depressurizing the high-pressure gas through the expander, consuming internal energy of the high-pressure gas to do work and deep cooling at the same time, and returning the waste steam liquid to the low-temperature liquid storage tank for storage; meanwhile, mechanical energy is output or the generator is driven to rotate to output electric energy;

further, a gas-liquid separator is arranged between the throttle valve inlet and the expander inlet, and liquid output by the gas-liquid separator is communicated with the throttle valve inlet; the high-pressure gas output by the gas-liquid separator is input and drives the expansion machine to rotate at a high speed to output mechanical energy or drive the generator to output electric energy; and when doing work, consuming the internal energy of the high-pressure fluid, and returning the low-temperature and low-pressure liquid to the low-temperature liquid storage tank for storage and standby.

In an eighth aspect, the low-temperature liquid storage tank is further provided with a cooling device, and the cooling device comprises the low-temperature liquid storage tank, a compressor, a condenser, a second throttling valve or a second expander or a turbine which are connected in sequence; the compressor is independently arranged or coaxially connected with the expander; or a set of electric power generation integrated machine is coaxially connected to the rotating shafts of the expander and the compressor which are coaxially connected; when the compressor is started or the power of the compressor is insufficient, the electric power generation integrated machine is a motor, and consumes electric energy to output power to drive the compressor; when the mechanical energy output by the expansion machine is larger than the power demand of the compressor, the electric power generation all-in-one machine is a generator, and the redundant mechanical energy generated by the high-speed rotation of the expansion machine is converted into electric energy to be output;

preferably, the compressor and the expander are coaxially connected into a whole device; the expander rotates at a high speed to drive the compressor which is coaxially connected to rotate at a high speed; the compressor absorbs and compresses low-temperature gas evaporated from the low-temperature liquid storage tank, and heat energy generated by the compressed gas of the compressor is released into low-temperature working medium fluid at the front end of an inlet of the expander through a condenser arranged between an outlet of a high-temperature pipeline of the dead steam heat regenerator and the expander;

When the expander is arranged independently, the condenser is arranged between the outlet of the high-temperature pipeline of the dead steam regenerator and the inlet of the expander; when the throttle valve is arranged in the system, the condenser is arranged between the high-pressure gas outlet of the gas-liquid separator and the expander;

the high-temperature end of the condenser exchanges heat with the high-pressure fluid at the inlet end of the expander, and the low-temperature end of the condenser exchanges heat with the high-pressure fluid at the outlet of the high-temperature pipeline of the exhaust steam regenerator; one end of the condenser connected with the outlet of the compressor is a high-temperature end of the condenser;

when the throttle valve is arranged in the system, the condenser is arranged between the high-pressure gas outlet of the gas-liquid separator and the expander;

the gas evaporated from the low-temperature liquid in the low-temperature liquid storage tank carries a large amount of latent heat of vaporization, is collected by the top of the low-temperature liquid storage tank and is conveyed to the compressor by a pipeline, then is compressed by the compressor and passes through the condenser, so that the high-pressure gas is condensed into liquid, and then returns to the low-temperature liquid storage tank for later use after throttling, pressure reduction and refrigeration by the second throttling valve or the second expansion machine;

preferably, when a second expander is used for realizing throttling pressure reduction work and realizing more deep cooling, the inlet of the second expander is high-pressure fluid, the outlet of the second expander is low-pressure fluid, the second expander or the turbine is driven to rotate at a high speed to do work and output mechanical energy, the high-pressure fluid flowing through the second expander or the turbine is refrigerated more deeply, and the lower-temperature liquid is returned to the low-temperature liquid storage tank for storage and standby; further, the second expander is coaxially connected with a second compressor, the second compressor is a supercharger and is arranged between the compressor and the condenser; the pressure of the fluid working medium in the condenser is increased;

Furthermore, the cooling device or the compression system also has a technical scheme for improving the gas density in the low-temperature liquid storage tank, and the technical scheme improves the output pressure of the expander and improves the gas density in the low-temperature liquid storage tank by improving the pressure of exhaust steam discharged by an exhaust pipeline of the low-temperature working medium supercritical gas turbine; enabling the compressor to continuously compress the high-density gas in the low-temperature liquid storage tank, and reducing the high-density gas into liquid after the energy is released by the condenser; the low-temperature liquid is throttled and decompressed by a second throttling valve or a second expansion machine or a turbine and then returns to the low-temperature liquid storage tank for standby.

In the ninth aspect, the system also comprises a waste heat resource power generation or combustion power generation system; the waste heat resources include but are not limited to various industrial waste heat resources, geothermal energy and solar energy photo-thermal energy; the industrial waste heat resources and the solar energy photo-heat a low-temperature power generation working medium in a main heat exchanger pipeline, and the low-temperature power generation working medium in the main heat exchanger pipeline absorbs waste heat or high-temperature heat energy generated by solar energy to form high-temperature and high-pressure gas which is input and drives the low-temperature working medium supercritical gas turbine to rotate at a high speed to output mechanical energy outwards or drive a generator to rotate to output electric energy outwards;

Furthermore, the combustion power generation system is composed of a fuel storage, a controller and a boiler which are sequentially communicated; the boiler consists of a combustor and a high-temperature main heat exchanger pipeline;

the fuel in the fuel storage is regulated and controlled by the controller and then is conveyed to a burner of the boiler to be combusted, and the generated high-temperature heat energy heats the pipeline of the high-temperature main heat exchanger; the low-temperature power generation working medium in the high-temperature main heat exchanger pipeline is heated at high temperature to form high-temperature high-pressure gas, and the high-temperature high-pressure gas is input and drives the low-temperature working medium supercritical gas turbine to rotate at high speed to output mechanical energy outwards or drives a generator to rotate at high speed to output electric energy outwards;

the fuel stored in the fuel storage comprises but is not limited to any one or more of biogas, natural gas, liquefied petroleum gas, biofuel, garbage, waste tires, straws, gasoline, diesel oil, coal fuel and nuclear fuel;

the system comprises a low-temperature liquid fuel combustion system, a low-temperature liquid fuel storage device, a heat exchanger, a controller and a boiler, wherein the low-temperature liquid fuel combustion system is formed by sequentially connecting the low-temperature liquid fuel storage device, the heat exchanger, the controller and the boiler; the heat exchanger is independently arranged to absorb the heat energy of the air in the environment; or the low-temperature working medium supercritical gas turbine is arranged between the low-temperature working medium supercritical gas turbine and the low-temperature liquid storage tank, and absorbs the heat energy of high-temperature exhaust steam; the cryogenic liquid fuel includes, but is not limited to, LNG liquid, liquid hydrogen;

The low-temperature liquid fuel stored in the low-temperature liquid fuel storage is conveyed to the heat exchanger through a pipeline to absorb the heat energy of the air in the environment and then is gasified to form combustible gas; or exchanging heat with high-temperature exhaust steam in an exhaust steam pipeline, on one hand, condensing the high-temperature and high-pressure exhaust steam into liquid and returning the liquid to the low-temperature liquid storage tank; meanwhile, the low-temperature liquid fuel absorbs the high-temperature exhaust steam heat energy output by the low-temperature working medium supercritical gas turbine exhaust pipeline and then is gasified into combustible gas, after the regulation and control of the controller, the combustible gas is conveyed to the boiler burner to be burnt to heat the low-temperature power generation working medium in the high-temperature main heat exchanger pipeline in the boiler, the low-temperature power generation working medium in the high-temperature main heat exchanger pipeline absorbs the high-temperature heat energy generated by the burning of the combustible gas to form high-temperature high-pressure gas, and the high-temperature high-pressure gas inputs and drives the low-temperature working medium supercritical gas turbine to rotate at a high speed to output mechanical energy outwards or drives the generator to rotate to output electric energy outwards;

furthermore, a low-temperature main heat exchanger is arranged outside the high-temperature main heat exchanger and/or the boiler flue, the low-temperature main heat exchanger fully absorbs heat energy generated by combustion of combustible gas in the boiler, and the heat energy generated by combustion of the combustible gas is fully utilized to do work and generate electricity;

Furthermore, the low-temperature main heat exchanger also exchanges heat with other heating equipment, so that the heat energy of other heating equipment is fully absorbed, and meanwhile, the other heating equipment is cooled;

furthermore, the low-temperature main heat exchanger exchanges heat with mesons such as hot air in the environment or hot water in the environment, the extremely low-temperature power generation working medium is used for absorbing heat energy of the air in the environment to do work, and the power generation efficiency and the power generation output of the system are further improved.

In a tenth aspect, the embodiment of the present invention is capable of better explaining the low-temperature working medium supercritical power generation system or power plant and the low-temperature working medium supercritical gas turbine or expander, and has practicability, novelty and creativity, and also provides a process for a low-temperature working medium supercritical power generation system or power plant for better understanding; the detailed description is as claimed in claim 10;

the embodiment of the invention has the beneficial effects that:

the embodiment of the invention provides a supercritical low-temperature working medium cylinder body shaft seal gas turbine device and a using method thereof, which certainly comprises an expander device, wherein the low-temperature working medium supercritical gas turbine is divided into a device input end, a device body and a device output end; the high-pressure gas working medium input by the input end of the device is a low-temperature power generation working medium with the boiling point temperature lower than zero degree centigrade under the standard atmospheric pressure; the low-temperature power generation working medium comprises but is not limited to carbon dioxide, ammonia, methane, nitrogen, air, hydrogen and helium; the structure of the low-temperature working medium supercritical gas turbine equipment needs to meet the physical characteristics of the density, the composition, the temperature and the pressure of the low-temperature power generation working medium;

The low-temperature working medium supercritical gas turbine equipment and low-temperature parts need to adopt low-temperature resistant materials, including but not limited to austenite low-temperature steel and ferrite low-temperature steel;

the temperature of high-pressure gas input by the input end of the low-temperature working medium supercritical gas turbine is obviously higher than the critical temperature of the low-temperature power generation working medium; the temperature of the exhaust steam discharged from the output end of the low-temperature working medium supercritical turbine reaches the critical temperature of the low-temperature power generation working medium;

the gas pressure input by the main steam pipeline of the low-temperature working medium supercritical turbine is required to be obviously higher than the critical pressure of the low-temperature power generation working medium; the exhaust steam pressure output by the exhaust pipeline of the low-temperature working medium supercritical gas turbine reaches the critical pressure of the low-temperature power generation working medium;

condensing high-temperature high-pressure exhaust steam reaching critical temperature and critical pressure by using extremely low-temperature liquid output by a low-temperature liquid pump, and condensing the high-temperature high-pressure exhaust steam;

compared with the traditional gas turbine or expander, the low-temperature working medium supercritical gas turbine or expander not only can be suitable for low-temperature working medium, but also greatly reduces the volume of equipment; the temperature of exhaust steam of the traditional gas turbine or expander needs to be reduced to be lower than the standard boiling point of a working medium by acting, so that the last-stage blade and the next-stage blade of the gas turbine are very long (the same expander is adopted), and the gas turbine or the expander is large in size, relatively high in material and manufacturing cost and large in size; the low-temperature working medium supercritical gas turbine or the expander is 'removed' from the position below the critical temperature point of the power generation working medium, the removed part is low in working medium density, the tail part and the position below the critical temperature of the gas turbine or the expander are removed, no waste steam latent heat is formed, and the volume, the weight and the manufacturing cost of the gas turbine or the expander are reduced.

The embodiment of the invention provides a gas turbine device for shaft sealing by adopting a gas turbine cylinder and a using method thereof, and the gas turbine device also comprises gas turbine devices such as an expander and the like; the cylinder body of the steam turbine or the expansion machine is static, the rotating speed of the rotor of the steam turbine or the rotor of the expansion machine is very high, shaft sealing needs to be carried out between the rotating shaft rotating at a high speed and the static cylinder body, otherwise, high-pressure gas input by the steam turbine leaks along the rotating shaft of the steam turbine, and the leakage pressure is very high. The steam turbine needs a shaft seal system, and the traditional steam turbine is provided with a tooth-shaped steam seal, a Brabender steam seal, a honeycomb steam seal, a brush steam seal, a flexible tooth steam seal and an elastic tooth steam seal; although the high-pressure air inlet end is provided with the shaft seal, the leakage of steam through the shaft seal cannot be avoided; the leakage rate of a large turbine can reach more than 10 tons per hour.

In the self-sealing system, in the starting and stopping processes of the steam turbine, the high-pressure end shaft seal has no steam, new steam subjected to temperature reduction and pressure reduction needs to be introduced and sent into the high-pressure end shaft seal and the low-pressure end shaft seal simultaneously, the system is combined with the self-sealing system after reaching about 80% of load, and the whole shaft seal system is quite complex. The rest of air leakage is discharged to the atmosphere through the signal tube after passing through a plurality of shaft sealing sheets, and the quality of the shaft seal operation can be monitored by observing the steam emission condition of the signal tube during operation. Especially, the cost of low-temperature organic working media is as high as about 10 ten thousand per ton, so the leakage cost of the shaft seal is quite expensive;

In the traditional steam turbine shaft seal system, a steam turbine main bearing and a bearing seat are arranged on the outer surface of a steam turbine, so that high-temperature and high-pressure main steam is prevented from entering a lubricating oil system to cause emulsification of lubricating oil, and further, the steam turbine bearing is damaged due to loss of lubrication, and even serious accidents are caused; in addition, the lubricating oil is worried about to leak into the main steam system, so that the pollution to the main steam can be caused;

aiming at the problems, through years of research and continuous technical improvement, the applicant forms a set of complete mechanism and protective measures, and can overcome and eliminate the problems; according to the embodiment of the invention, a highly airtight structure of a cylinder body of a gas turbine is adopted to solve the problem of leakage at two ends of a rotating shaft of the gas turbine or an expander; because the internal pressure of the cylinder body of the gas turbine is the same, high-temperature and high-pressure steam is difficult to enter the bearing and the bearing seat, and meanwhile, the high-efficiency heat insulation shell is arranged to completely protect the bearing and the bearing seat and prevent high temperature from entering the heat insulation shell to influence the temperature of the bearing, the bearing seat and lubricating oil; meanwhile, multiple isolation measures are arranged between the main steam inlet and the high-efficiency heat insulation shell; in addition, the high-efficiency heat insulation shell is also provided with an output system for outputting high-temperature and dirty lubricating oil, and a filtering and cooling system for ensuring that the lubricating oil keeps a low-temperature state; even high-temperature steam is difficult to enter the bearing and the bearing seat with multiple heat insulation protection; in other words, the gas turbine equipment for shaft sealing of the gas turbine cylinder body provided by the embodiment of the invention is mainly applied to the low-temperature power generation working medium, and the temperature and the pressure of the low-temperature power generation working medium are not as high as those of the traditional high-temperature high-pressure main steam; therefore, the low-temperature power generation working medium gas turbine is very suitable for a low-temperature power generation working medium gas turbine with high cost, a cylinder body is adopted to achieve an efficient airtight structure of nearly 100%, and shaft sealing of the low-temperature power generation working medium gas turbine is carried out, so that not only can a nearly 0 leakage effect be realized, but also the volume and the manufacturing cost of the low-temperature power generation working medium gas turbine equipment can be reduced;

In order to better illustrate that the embodiment of the invention has practicability, novelty and creativity and simultaneously facilitate better understanding, the embodiment of the invention also provides a use method and a process of the low-temperature working medium supercritical gas turbine equipment;

the bearing systems of the input end and the output end of the low-temperature working medium supercritical gas turbine or the expansion machine are hidden in the cylinder body of the low-temperature working medium supercritical gas turbine or the expansion machine, and the problem of leakage of the low-temperature working medium supercritical gas turbine or the expansion machine at two ends of a rotating shaft can be solved by using the high-tightness structure (up to 100 percent sealing) of the cylinder body of the gas turbine or the expansion machine; the rotating shaft sealing system provided by the embodiment of the invention is also suitable for other rotating mechanical equipment such as expanders, pneumatic machines, screw machines and the like, and the high-pressure gas input end and the high-pressure gas output end can also adopt the same sealing technology and method as those of the low-temperature working medium supercritical gas turbine or expander equipment, so that the near-zero leakage of the rotating shaft sealing system is realized and achieved, and the rotating shaft sealing system also belongs to the scope provided by the embodiment of the invention.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts; this is easily done. For better illustration, the embodiment of the present invention only takes the low-temperature working medium supercritical gas turbine as an example, and other pneumatic machines and expansion machines are the same and different, and thus, the drawing and the description are not repeated.

FIG. 1 is a schematic view of a low temperature nitrogen conventional turbine with bearings outside the cylinder, the turbine having exhaust steam temperature as low as the normal boiling point of nitrogen (-196 deg.C) for reference and comparison;

fig. 2 is a schematic structural diagram of a gas turbine device input end bearing, an output end bearing and a generator all placed in a gas turbine cylinder according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a low-temperature working medium supercritical gas turbine in which a bearing at an input end, a bearing at an output end and a generator of a gas turbine device are all placed in a cylinder body of the gas turbine, and exhaust steam temperature at the output end reaches critical temperature of nitrogen (-147 ℃);

FIG. 4 is a schematic connection diagram of a method for using a supercritical low-temperature working medium cylinder shaft seal gas turbine device with a throttle valve according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a connection of a method for using a cryogenic supercritical low-temperature working medium cylinder shaft seal gas turbine apparatus with an expander according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a method of using a cryogenic working medium turbine apparatus with an expander cryogenic and coaxial compressor cryogenic and combustion system in accordance with an embodiment of the present invention;

Gas turbine section icon: (other gas turbine equipment and the gas turbine are slightly different from each other only in the equipment body, the characteristics of the embodiment of the invention are changed in the same way, and repeated description is omitted); 21-gas turbine exhaust duct; 101-a gas turbine shaft; 102-an insulating shell; 103-input end bearing and bearing seat; 104-a shaft seal; 105-a gas turbine apparatus cylinder; 106-rotor impeller; 107-gas turbine diaphragm; 108-output shaft seal; 9-an output end heat insulation shell; 10-output end bearing and bearing seat; 11-a coupling; 12-a generator; 13-a third pipeline valve; 14-a third conduit outlet; 15-a second conduit outlet; 16-a second pipeline valve; 17-reserving space or pipeline at the output end; 18-reserving a heat insulation area at the output end; 19-reserving a heat insulation area at an input end; 22-insulating shell sealing; 23-reserving space or pipeline at the input end; 24-a first pipeline valve; 25-a first conduit outlet; 26-a lubricant output conduit; 27-a lubricating oil reservoir; 28-lube oil filter; 29-a lube oil cooler; 30-a lubricating oil pump; 31-a lubricating oil high pressure input pipeline; 32-output end heat insulation shell sealing;

power generation section icon: 1-a cryogenic liquid storage tank; 2-a cryogenic liquid pump; 3-a dead steam regenerator; 301-low temperature pipeline of exhaust steam heat regenerator; 302-high temperature pipeline of exhaust steam regenerator; 4-a primary heat exchanger; 401 — low temperature main heat exchanger; 402-high temperature main heat exchanger or boiler; 5-low temperature working medium supercritical gas turbine; 6-a generator; 7-a throttle valve; 77-an expander; 78-coaxial compressor; 8-a generator; 9-a condenser; 10-a second throttle or second expander; 100-cryogenic liquid fuel storage; 110-a heat exchanger; 111-a controller;

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the embodiments of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

as shown in fig. 1, in a conventional gas turbine plant, bearings at both ends of a gas turbine rotating shaft 101, including an input end bearing and bearing housing 103, an output end bearing and bearing housing 10, a coupling 11 and a generator 12, are generally disposed outside a cylinder block 105 of the gas turbine plant; shaft end sealing at two ends of a rotating shaft 101 of the gas turbine is realized by an input end shaft seal 104 and an output end shaft seal 108, and the traditional shaft seals comprise a tooth-shaped steam seal, a Braiden steam seal, a honeycomb steam seal, a brush steam seal, a flexible tooth steam seal and an elastic tooth steam seal; the leakage problem of the gas turbine still exists although the gas turbine is provided with a shaft seal, and the leakage amount of the gas seal of the existing large-scale gas turbine can reach more than 10 tons per hour. The leakage is also large, especially for the low-temperature liquid working medium with high cost, and the shaft end steam seal leakage is very painful.

The low-temperature nitrogen working medium gas turbine of a traditional Rankine cycle shown in figure 1 is characterized in that the temperature of input gas of a main steam pipeline 20 of the gas turbine is above 0 ℃, the steam does work in gas turbine equipment, the temperature is continuously reduced, when the temperature is reduced to a-147 ℃ critical temperature position (latent heat is 0) marked in figure 1, when the temperature of the gas is lower than the critical temperature of the nitrogen, latent heat begins to exist in dead steam, and the latent heat stored in the nitrogen is increased along with the reduction of the temperature of the dead steam, the temperature of an exhaust pipeline 21 of the gas turbine is reduced to-196 ℃ boiling point temperature of the nitrogen, the latent heat reaches 199kj/kg, and as the temperature of the dead steam is very low, the huge low-grade latent heat energy is difficult to be released, the Rankine cycle is difficult to perform, and the main reason that low-temperature working medium power generation is difficult to realize is.

in order to solve the problem of leakage at two ends of a rotating shaft of a gas turbine device, the applicant discovers through research in recent 20 years that the problem of leakage at two ends of the rotating shaft of the gas turbine device is solved by hiding an input end and an output end of the gas turbine into a cylinder body of the gas turbine and using a highly-closed structure (up to 100% sealing) of the cylinder body of the gas turbine;

As shown in fig. 2, the high pressure inlet 20 and the top line a to the left are intended to mean the input to the gas turbine apparatus; between the main steam pipeline 20 and the exhaust steam pipeline 21 is the turbine equipment body, as shown in the middle part B between the line A and the line C; the steam exhaust pipeline 21 and the line C at the top part are indicated to the right as the output end of the gas turbine equipment;

in the turbine shown in FIG. 2, the insulated casing 102 comprises an upper insulated casing and a lower insulated casing (the lower insulated casing of the turbine shown in FIG. 2); the lower heat insulation shell is arranged at the end bearing position of the rotating shaft 101 of the gas turbine, is arranged in the lower cylinder body and is tightly combined with the lower cylinder body of the gas turbine cylinder body 105; the input end bearing and the bearing seat 103 are arranged in the lower heat insulation shell of the heat insulation shell 102, support the weight of the rotating shaft 101 of the gas turbine, and limit the axial movement of the rotating shaft 101 of the gas turbine by a thrust bearing; the contact position of the heat insulation shell 102 and the turbine rotating shaft 101 is provided with a heat insulation shell seal 22, and the heat insulation shell seal 22 prevents the bearing lubricating oil in the heat insulation shell 102 from leaking outwards from the heat insulation shell seal 22;

optionally, a shaft seal 104 is further arranged between the high-pressure air inlet 20 and the input end, and optionally, a heat insulation region 19 is further arranged between the shaft seal 104 and the heat insulation housing 102, so as to isolate and reduce the high temperature input by the high-pressure main steam pipeline 20, and influence the heat insulation housing 102 and the input end bearing and the bearing seat 103 therein; since the upper and lower heat-insulating shells of the heat-insulating shell 102 are of a sealed structure and have the same pressure as the input pressure of the high-pressure gas inlet 20, the high-pressure gas input from the high-pressure gas inlet 20 is difficult to enter the heat-insulating shell 102. Also shaft seal 104 and insulated housing seal 22; two heat insulation shell seals 22 can be arranged, so that high-temperature and high-pressure gas input by the main steam pipeline 20 can hardly enter the heat insulation shell seals, and meanwhile, lubricating oil in the heat insulation shell 102 can be prevented from being leaked out difficultly;

Optionally, an input end reserved space or pipeline 23 is further provided between the insulation shell seal 22 and the input end reserved insulation area 19, the input end reserved space or pipeline 23 is isolated, and meanwhile, lubricating oil leaked from the insulation shell seal 22 is stored and discharged through a first pipeline valve 24 and a first pipeline outlet 25;

preferably, as shown in fig. 2, a lubricant oil output pipeline 26, a lubricant oil storage 27, a lubricant oil filter 28, a lubricant oil cooler 29, a lubricant oil pump 30 and a lubricant oil high-pressure input pipeline 31 which are connected with the heat insulation shell 102 are further arranged outside the heat insulation shell 102 and the lower cylinder 105, and sufficient, clean and low-temperature (temperature-controlled) lubricant oil is conveyed into the heat insulation shell 102 through the lubricant oil high-pressure input pipeline 31 and is provided for the input-end bearing and the bearing seat 103, so that sufficient, clean and low-temperature lubricant oil is guaranteed; ensuring safe and stable operation of the input end bearing and bearing housing 103.

The lubricant reservoir 27, lubricant filter 28, lubricant cooler 29, which may be combined, then deliver lubricant to the bearings and bearing blocks 103 within the insulated housing 102 via lubricant pump 30 and lubricant high pressure input line 31;

The lubricating oil filter 28, the lubricating oil cooler 29, and the lubricating oil pump 30 may be provided outside the cylinder block 105 of the gas turbine apparatus; the lubricating oil cooler 29 may be provided inside a cylinder of the gas turbine, and when the lubricating oil cooler 29 is provided inside the cylinder, the lubricating oil cooler 29 may have a pipe communicating with the outside, and may be configured to transfer heat of the lubricating oil in the cylinder to the outside of the cylinder by the medium flowing in the pipe, and to return to the inside of the cylinder after being cooled by a heat exchanger.

Preferably, the input end and the output end of the gas turbine are both placed inside a cylinder 105 of the gas turbine equipment, and the shaft end of the gas turbine rotating shaft 101 is sealed by using a highly airtight structure (close to 100% sealing) of the gas turbine cylinder, so that high-pressure gas is prevented from leaking from shaft seals at two ends of the gas turbine rotating shaft 101. The output end of the gas turbine comprises the following embodiments: an output end bearing and bearing housing 10 disposed at a location remote from the output end shaft seal 108; preferably, the output end is reserved with a heat insulation area 18; the bearing and the bearing seat 10 of the output end are arranged in the heat insulation shell 9 of the output end, the heat insulation shell 9 of the output end has the same structure as the input end and is divided into a lower heat insulation shell and an upper heat insulation shell, the lower heat insulation shell is tightly combined with the lower cylinder of the cylinder 105 of the gas turbine equipment, the upper heat insulation shell and the lower heat insulation shell of the output end are fastened through flanges and bolts, and a closed heat insulation space is formed inside the upper heat insulation shell and the lower heat insulation shell; optionally, a lubricating oil injection hole is formed in the top of the upper heat insulation shell, so that lubricating oil is injected into the heat insulation space between the bearing and the bearing seat 10; the specific implementation is the same as the input end, and redundant description is omitted; it should be noted that the output end heat insulation housing 9 and the rotating shaft 101 have two contact positions, and therefore, the output end heat insulation housing seals 32 have two contact positions, which are respectively arranged in contact with the rotating shaft 101 as shown in fig. 3; the output end heat insulation shell seal 32 prevents the bearing lubricating oil in the output end heat insulation shell 9 from leaking outwards from the output end heat insulation shell seal 32; the shaft end of the output end gas turbine rotating shaft 101 is also provided with a shaft coupling 11 for coupling with the rotating shaft of the generator 12, so that the generator 12 is convenient to overhaul and replace;

Optionally, the output end reserved space or pipeline 17 is respectively arranged in the lower cylinder 105 at two sides of the output end heat insulation shell 9, stores the lubricating oil leaked from the output end heat insulation shell seal 32, and discharges the leaked lubricating oil through the second pipeline valve 16 and the third pipeline valve 13; the output side generator 12 generates electric power, which is led out through a terminal provided in the cylinder block 105 of the gas turbine equipment, and does not affect the sealing performance of the gas turbine.

The high-pressure main steam pipeline 20 of the gas turbine and the exhaust pipeline 21 of the gas turbine are fastened by adopting flanges and screws with excellent sealing performance, and leakage cannot occur, so that the gas turbine equipment provided by the embodiment of the invention has multiple sealing measures. It should be noted that the sealing system for a rotating shaft provided by the embodiment of the present invention can also adopt the same sealing technology and method as those of the gas turbine equipment for other rotating mechanical equipment, namely, a high-pressure gas input end and a high-pressure gas output end, so as to realize and achieve near-zero leakage of the sealing system for the rotating shaft, and the sealing system also belongs to the category. The technology is relatively independent and has independent technical characteristics, and when the technology is cited, the applicant needs to obtain approval.

in fig. 3, the sealing performance (which can reach nearly 100%) of the system can reach nearly zero leakage as that of fig. 2 by adopting the cylinder body of the gas turbine equipment for shaft end sealing; the low-temperature power generation working medium is close to zero leakage, so that the loss of the low-temperature power generation working medium with high cost can be reduced, and the overall power generation efficiency of the power generation system and the power system can be improved;

as shown in fig. 3, when the temperature of the low-temperature working medium supercritical gas turbine provided in the embodiment of the present invention is lowered to the critical temperature of the power generation working medium nitrogen (about-147 ℃, latent heat is 0), or when the pressure of the exhaust steam is lowered to the critical pressure, the low-temperature working medium supercritical gas turbine does not continue to work, but directly exhausts the low-temperature working medium supercritical gas turbine through the exhaust pipe 21, at this time, the exhaust steam has no latent heat, the latent heat is 0, and latent heat changes sensible heat. Then condensing the high-temperature exhaust steam with critical temperature by using extremely low-temperature liquid nitrogen output by the low-temperature liquid pump 2; therefore, the low-temperature working medium supercritical gas turbine has the advantages of small volume, strong power and low cost; meanwhile, the gate is opened for realizing low-grade heat energy power generation, hot water power generation, hot air power generation and ultralow temperature waste heat resource utilization;

Meanwhile, the system can also burn biogas, natural gas, liquefied petroleum gas, biofuel, garbage, waste tires, straws, gasoline, diesel oil, coal and nuclear fuel; the higher the temperature of the heat source is, the greater the mechanical energy output or the output for driving the generator to generate electricity is; the system is not provided with a cooling tower heat dissipation system; almost no energy is discharged to the outside, and therefore the efficiency of the power generation system and equipment is high.

in fig. 4, the power generation working medium stored in the low-temperature liquid storage tank 1 is liquid nitrogen (about-196 ℃), the pressure is increased by the low-temperature liquid pump 2, and the power generation working medium flows through the low-temperature pipeline 301 of the exhaust steam heat regenerator and is conveyed to a low-temperature main heat exchanger 401 (such as a hot water heat exchanger) of the main heat exchanger 4 to be heated to above 0 ℃; the low-temperature power generation working medium liquid nitrogen absorbs heat to form high-pressure gas, the pressure reaches more than 3Mpa, and the high-pressure gas is input into and drives the low-temperature working medium supercritical gas turbine (or expander) 5 to rotate at a high speed to do work; outputting mechanical energy or driving the generator 6 to rotate at high speed to output electric energy; the temperature of the dead steam discharged by the low-temperature working medium supercritical gas turbine 5 reaches or approaches to the critical temperature (latent heat 0) of nitrogen at about-147 ℃, the pressure of the dead steam reaches about 1Mpa, liquid nitrogen at-196 ℃ output by a low-temperature liquid pump 2 (the pressure of the dead steam can be higher according to the requirement) is used for condensing the dead steam at the high temperature of about-147 ℃ into liquid nitrogen, the liquid nitrogen is throttled and decompressed and refrigerated by a throttle valve 7, and the liquid nitrogen at low temperature and low pressure is output and returned to the low-temperature liquid storage tank 1 for later use;

Liquid nitrogen below about-196 ℃ in the low-temperature liquid storage tank 1 is pressurized and conveyed into a low-temperature pipeline 301 of the exhaust steam heat regenerator through a low-temperature liquid pump 2, and absorbs high-pressure high-temperature exhaust steam heat energy of about-147 ℃ and about 1Mpa which is conveyed into a high-temperature pipeline 302 of the exhaust steam heat regenerator by the low-temperature working medium supercritical gas turbine 5, the liquid nitrogen temperature is raised to about-148 ℃, and the liquid nitrogen is conveyed into the main heat exchanger 4 from an outlet of the low-temperature pipeline 301 of the exhaust steam heat regenerator and is reheated to more than 0 ℃ to form high-temperature high-pressure nitrogen which drives the low-temperature working medium supercritical gas turbine 5 to rotate at high speed to apply work, output mechanical energy or drive a generator 6 to generate electricity, and circulate continuously to generate electricity and.

the only difference between fig. 5 and fig. 4 is that the throttle valve 7 is replaced by an expander 77 in the embodiment of the present invention, and the expander 77 can use high-pressure fluid and pressure energy of about 1Mpa to perform work (the steam exhaust pressure can be higher according to the requirement); high-temperature high-pressure exhaust steam output by an exhaust pipeline of the low-temperature working medium supercritical gas turbine 5; the high-pressure fluid is conveyed to an expander 77, the fluid at the inlet of the expander 77 is high-pressure, the fluid at the outlet of the expander 77 is low-pressure, and liquid nitrogen with low pressure and low temperature is returned to the low-temperature liquid storage tank 1 by throttling, pressure reduction and work application of the expander 77; because of the huge pressure difference between the input end and the output end of the expansion machine 77, the expansion machine 77 is driven to rotate at a high speed to output mechanical energy or drive the generator 8 to output electric energy; the expander rotates at a high speed to do work outwards, so that the internal energy of the low-temperature working medium fluid is consumed, and the temperature of the low-temperature working medium fluid returned to the low-temperature liquid storage tank 1 is lower; the temperature of the low-temperature liquid in the low-temperature liquid storage tank 1 can be cooled more favorably, the liquid nitrogen with lower temperature output by the low-temperature liquid pump 2 can condense the high-temperature and high-pressure exhaust steam in the high-temperature pipeline 302 of the exhaust steam heat regenerator, and the high-temperature and high-pressure exhaust steam can be condensed more favorably; meanwhile, the expansion machine 7 rotates at a high speed to output mechanical energy or drive the generator 8 to output electric energy;

on the basis of fig. 6 and 5, the expander 77 rotates at a high speed, and drives the coaxially connected compressor 78 to rotate at a high speed; the pipeline inlet of the compressor 78 is communicated with the top of the low-temperature liquid storage tank 1, the evaporated gas in the low-temperature liquid storage tank 1 is collected and compressed into high-pressure high-temperature gas, the high-pressure high-temperature gas is conveyed to the condenser 9 to be condensed into liquid, and after throttling, pressure reduction and refrigeration are carried out through the second throttling valve or the second expansion machine 10, low-pressure low-temperature liquid nitrogen is returned to the low-temperature liquid storage tank 1, and the low-pressure low-temperature liquid nitrogen is continuously circulated in such a way to continuously cool the low-temperature liquid in the;

the condenser 9 is arranged between the outlet of the high-temperature pipeline 302 of the exhaust steam regenerator and the inlet of the expander 77, and inputs high-temperature energy generated by gas compressed by the compressor 78 and drives the expander 77 to rotate at a high speed, so as to output mechanical energy or drive the generator 8 to output electric energy; preferably, the generator 8 is an electric and power generation integrated machine; when the compressor 78 is started or the power is insufficient, the electric-power generation all-in-one machine 8 drives the compressor 78 through the output power of the motor; when the expansion 77 output is greater than the compressor 78 demand, the motor-generator-integrated machine 8 acts as a generator, converting the mechanical energy of the expansion output to electrical energy output.

Further, the system comprises a combustion system or a combustion system of low-temperature liquid fuel, wherein the combustion system of the low-temperature liquid fuel is composed of a low-temperature liquid fuel storage 100, a heat exchanger 110, a controller 111 and a high-temperature main heat exchanger or boiler 402 which are connected in sequence;

the LNG low-temperature liquid in the low-temperature liquid fuel storage 100 is conveyed to the heat exchanger 110 through a pipeline to absorb ambient air heat energy or high-temperature exhaust steam heat energy, gasified to form combustible gas (the common normal-temperature fuel does not need the heat exchanger 110), controlled and adjusted by the controller 111, and conveyed to the boiler 402 to burn and heat the high-temperature main heat exchanger or the boiler 402, the temperature of a heated pipeline reaches more than 200 ℃, so that the high-temperature main heat exchanger or the boiler 402 is gasified by a low-temperature power generation working medium in the heated pipeline to form high pressure, and the high-temperature power generation working medium is input and drives the low-temperature working medium supercritical gas turbine 5 to rotate at a high speed to output mechanical energy outwards or drives the generator 6 to;

the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The supercritical low-temperature working medium cylinder body shaft seal gas turbine equipment and the use method are characterized in that a working medium input by a main steam pipe of the low-temperature working medium supercritical gas turbine equipment is a low-temperature working medium with the boiling point temperature lower than zero degree centigrade under the standard atmospheric pressure; the high-pressure gas working medium comprises any one or a plurality of combinations of carbon dioxide, ammonia gas, methane, ethane, nitrogen, air, oxygen, argon, hydrogen and helium;

the temperature of high-pressure gas input by a main steam pipe of the low-temperature working medium supercritical gas turbine is obviously higher than the critical temperature of a low-temperature power generation working medium; the temperature of the exhaust steam discharged by the low-temperature working medium supercritical turbine reaches or is slightly higher than the critical temperature of the low-temperature power generation working medium;

the pressure of high-pressure gas input by a main steam pipe of the low-temperature working medium supercritical gas turbine is obviously higher than the critical pressure of a low-temperature power generation working medium; the pressure of the exhaust steam discharged by the low-temperature working medium supercritical turbine reaches or approaches to the critical pressure of the low-temperature power generation working medium;

the low-temperature working medium supercritical gas turbine belongs to a rotary power machine for converting high-temperature and high-pressure gas energy into mechanical power, and is also called as a gas turbine, wherein the gas turbine comprises but is not limited to a gas turbine, a pneumatic machine, a gas screw expander and a gas turbine expander;

the low-temperature working medium supercritical gas turbine and the corresponding connecting pipeline are also wrapped by a heat insulating layer; the thermal insulation layer has good thermal insulation performance, and comprises vacuum thermal insulation, aerogel, foam materials, fiber materials, glass wool and high-silicon cotton.

2. The supercritical low temperature working medium cylinder shaft seal gas turbine equipment and the use method thereof according to claim 1, wherein the low temperature working medium supercritical gas turbine or expander further comprises a cylinder shaft seal system; the gas turbine or the expander of the cylinder shaft seal system is composed of a static part and a rotating part; the gas turbine or the expander cylinder body shaft seal system comprises an input end shaft seal system and an output end shaft seal system; the input end shaft seal system of the gas turbine comprises an input end cylinder body, an input end bearing, a bearing seat, an input end rotating shaft and a main steam pipeline; the input end bearing and the bearing seat comprise a support bearing and a thrust bearing;

A heat insulation shell is arranged outside the input end bearing and the bearing seat; the insulated shell is divided into an upper insulated shell and a lower insulated shell; the lower heat insulation shell is arranged in a lower cylinder at the position of the input end bearing and the bearing seat and is tightly combined with the lower cylinder of the gas turbine; the input end bearing and the bearing seat are arranged in a lower heat insulation shell in a lower cylinder of the gas turbine;

the lower heat insulation shell and the upper heat insulation shell are provided with flanges, and the lower heat insulation shell and the inner cavity of the upper heat insulation shell form a closed heat insulation space through the fastening of the flanges and bolts; the input end rotating shaft, the input end bearing, the bearing seat and lubricating oil are sealed in a heat insulation space formed by the heat insulation shell;

the heat insulation shell wraps the contact position of the input end rotating shaft, and a heat insulation shell seal is further arranged, and the heat insulation shell seal prevents bearing lubricating oil in the heat insulation shell from leaking outwards from the heat insulation shell seal.

3. The supercritical low-temperature working medium cylinder shaft seal gas turbine equipment and the use method thereof as claimed in claims 1-2, characterized in that the upper heat insulation shell and the lower heat insulation shell of the heat insulation shell are fastened through the flange and the bolt, a closed heat insulation space is formed inside, and a lubricating oil injection hole is arranged at the top of the upper heat insulation shell, so that lubricating oil is injected into the heat insulation space of the bearing and the bearing seat;

preferably, a lubricating oil temperature pressure probe, a lubricating oil quantity probe and a pressure probe in the gas turbine cylinder are further arranged inside or outside the cylinder of the gas turbine equipment;

4. The supercritical low temperature working medium cylinder shaft seal gas turbine equipment and the use method thereof according to claims 1-3, characterized in that the output end of the gas turbine comprises a gas turbine exhaust pipeline, an output end cylinder, an output end bearing and bearing seat, a coupling and a generator; the gas turbine hides an output end bearing, a bearing seat, a coupler and a generator in an output end cylinder body of the gas turbine;

the input end of the gas turbine and the output end of the gas turbine are hidden in the gas turbine cylinder, shaft seals at two ends of a rotating shaft are carried out by utilizing a highly closed structure of the gas turbine cylinder, and low-temperature working media are prevented from leaking from the shaft seals at two ends of the rotating shaft of the gas turbine.

5. The supercritical low-temperature working medium cylinder body shaft seal gas turbine equipment and the use method thereof according to claims 1-4, characterized by comprising a low-temperature liquid storage tank, a low-temperature liquid pump, a steam exhaust heat regenerator low-temperature pipeline, a main heat exchanger, a low-temperature working medium supercritical gas turbine and a steam exhaust heat regenerator high-temperature pipeline which are sequentially communicated; the outlet of the high-temperature pipeline of the exhaust steam heat regenerator is connected with the inlet of the low-temperature liquid storage tank to form circulation;

the low-temperature pipeline of the dead steam regenerator is arranged between the low-temperature liquid pump and the main heat exchanger; the exhaust steam heat regenerator high-temperature pipeline is arranged between the outlet of the low-temperature working medium supercritical gas turbine exhaust pipeline and the low-temperature liquid storage tank; the low-temperature pipeline of the exhaust steam heat regenerator and the high-temperature pipeline of the exhaust steam heat regenerator exchange heat fully to form an exhaust steam heat regenerator with high-efficiency heat exchange; the exhaust steam heat regenerator is independently arranged or combined with the low-temperature working medium supercritical gas turbine;

6. The supercritical low-temperature working medium cylinder body shaft seal gas turbine equipment and the use method thereof as claimed in claim 5, characterized by further comprising a throttle valve or an expander, wherein the throttle valve is arranged between the outlet of the high-temperature pipeline of the exhaust steam regenerator and the inlet of the low-temperature liquid storage tank;

the system further comprises an expander or a turbine, wherein the expander or the turbine is arranged between the outlet of the high-temperature pipeline of the dead steam heat regenerator and the inlet of the low-temperature liquid storage tank;

the expansion machine consumes the internal energy of the high-pressure fluid to do work outwards while realizing throttling and pressure reduction, and realizes deeper refrigeration of the high-pressure fluid flowing through the expansion machine and returns the lower-temperature working medium liquid to the low-temperature liquid storage tank for storage and standby application while doing work outwards;

the expansion machine is independently provided with or closes a throttle valve, all high-pressure fluid enters the expansion machine to do work, the high-pressure fluid realizes throttling and pressure reduction through the expansion machine, internal energy of the high-pressure gas is consumed to do work outwards and realize deep cooling, and the dead steam liquid returns to the low-temperature liquid storage tank to be stored for later use; meanwhile, mechanical energy is output or the generator is driven to rotate to output electric energy;

further, when the high-pressure steam exhaust fluid output by the high-temperature pipeline outlet of the steam exhaust heat regenerator is in a gas-liquid mixed state, preferably, the high-pressure liquid is throttled and depressurized by the throttle valve and then returns to the low-temperature liquid storage tank for storage; throttling and depressurizing the high-pressure gas through the expander, consuming internal energy of the high-pressure gas to do work and deep cooling at the same time, and returning the waste steam liquid to the low-temperature liquid storage tank for storage; meanwhile, mechanical energy is output or the generator is driven to rotate to output electric energy;

further, a gas-liquid separator is arranged between the throttle valve inlet and the expander inlet, and liquid output by the gas-liquid separator is communicated with the throttle valve inlet; the high-pressure gas output by the gas-liquid separator is input and drives the expansion machine to rotate at a high speed to output mechanical energy or drive a generator to output electric energy; and when doing work, consuming the internal energy of the high-pressure fluid, and returning the low-temperature and low-pressure liquid to the low-temperature liquid storage tank for storage and standby.

7. The supercritical low-temperature working medium cylinder shaft seal gas turbine equipment and the use method thereof as claimed in claims 5 to 6, wherein the low-temperature liquid storage tank is further provided with a cooling device, and the cooling device comprises the low-temperature liquid storage tank, a compressor, a condenser, a second throttle valve or a second expander or a turbine which are connected in sequence; the compressor is independently arranged or coaxially connected with the expander; or a set of electric power generation integrated machine is coaxially connected to the rotating shafts of the expander and the compressor which are coaxially connected;

when the compressor is started or the power of the compressor is insufficient, the electric power generation all-in-one machine is a motor, consumes electric energy and outputs power to drive the compressor; when the mechanical energy output by the expansion machine is larger than the power demand of the compressor, the electric power generation all-in-one machine is a generator, and the redundant mechanical energy generated by the high-speed rotation of the expansion machine is converted into electric energy to be output;

preferably, the compressor and the expander are coaxially connected into a whole device; the expander rotates at a high speed to drive the compressor which is coaxially connected to rotate at a high speed; the compressor absorbs and compresses low-temperature gas evaporated from the low-temperature liquid storage tank, and heat energy generated by the compressed gas of the compressor is released into low-temperature working medium fluid at the front end of an inlet of the expander through a condenser arranged between an outlet of a high-temperature pipeline of the exhaust steam heat regenerator and the expander;

the gas evaporated from the low-temperature liquid in the low-temperature liquid storage tank carries a large amount of latent heat of vaporization, is collected by the top of the low-temperature liquid storage tank and is conveyed to the compressor by a pipeline, then is compressed by the compressor and passes through the condenser, so that the high-pressure gas is condensed into liquid, and then returns to the low-temperature liquid storage tank after throttling, pressure-reducing and refrigerating by the second throttling valve or the second expansion machine;

Furthermore, the cooling device or the compression condensing system also has a technical scheme for improving the gas density in the low-temperature liquid storage tank, and the technical scheme improves the output pressure of the expansion machine and improves the gas density in the low-temperature liquid storage tank by improving the pressure of exhaust steam discharged by an exhaust pipeline of the low-temperature working medium supercritical gas turbine; enabling the compressor to continuously compress the high-density gas in the low-temperature liquid storage tank, and reducing the high-density gas into liquid after the energy is released by the condenser; and the low-temperature liquid returns to the low-temperature liquid storage tank after being throttled and depressurized by a second throttling valve, a second expansion machine or a turbine.

8. The supercritical low-temperature working medium cylinder shaft seal gas turbine equipment and the use method thereof according to claims 5 to 7 are characterized by further comprising a waste heat resource power generation or combustion power generation system; the waste heat resources include but are not limited to various industrial waste heat resources, geothermal energy and solar energy photo-thermal energy; the industrial waste heat resource and solar photo-thermal system heats a low-temperature power generation working medium in a main heat exchanger pipeline, the low-temperature power generation working medium in the main heat exchanger pipeline absorbs high-temperature heat energy generated by waste heat or solar energy to form high-temperature and high-pressure gas, and the high-temperature and high-pressure gas is input and drives the low-temperature working medium supercritical gas turbine to rotate at a high speed to output mechanical energy or drive a generator to rotate to output electric energy;

the system comprises a low-temperature liquid fuel storage, a heat exchanger, a controller and a boiler, wherein the low-temperature liquid fuel storage, the heat exchanger, the controller and the boiler are sequentially connected; the heat exchanger is independently arranged to absorb the heat energy of the air in the environment; or the heat energy of the high-temperature exhaust steam is absorbed between the low-temperature working medium supercritical gas turbine and the low-temperature liquid storage tank; the cryogenic liquid fuels include, but are not limited to, LNG liquid, liquid hydrogen;

The low-temperature liquid fuel stored in the low-temperature liquid fuel storage is conveyed to the heat exchanger through a pipeline to absorb the heat energy of the air in the environment and then is gasified to form combustible gas; or exchanging heat with high-temperature exhaust steam in an exhaust steam pipeline, on one hand, condensing the high-temperature and high-pressure exhaust steam into liquid and returning the liquid to the low-temperature liquid storage tank; meanwhile, the low-temperature liquid fuel absorbs the high-temperature exhaust steam heat energy output by the low-temperature working medium supercritical gas turbine exhaust pipeline and then is gasified into combustible gas, after the low-temperature liquid fuel is regulated and controlled by the controller, the combustible gas is conveyed to the boiler burner to be combusted, the low-temperature power generation working medium in the high-temperature main heat exchanger pipeline in the boiler is heated, the low-temperature power generation working medium in the high-temperature main heat exchanger pipeline absorbs the high-temperature heat energy generated by the combustion of the combustible gas to form high-temperature high-pressure gas, and the high-temperature high-pressure gas is input and drives the low-temperature working medium supercritical gas turbine to rotate at high speed to output mechanical energy outwards or drives the;

furthermore, the low-temperature main heat exchanger and hot air or solar photo-thermal energy in the environment are utilized, the extremely low-temperature power generation working medium absorbs heat energy and/or solar heat energy in the air in the environment to do work, and the power generation efficiency and output of the system are further improved.

9. The supercritical low-temperature working medium cylinder shaft seal gas turbine equipment and the use method thereof as claimed in claims 5 to 8, wherein the low-temperature liquid storage tank is a pressure vessel for low-temperature liquid storage which has safety valve protection measures and good heat insulation performance; the stored working medium is a low-temperature liquid working medium with the boiling point temperature lower than zero degree centigrade under the standard atmospheric pressure; the low-temperature liquid working medium comprises any one or a plurality of combinations of carbon dioxide, methane, ethane, liquid nitrogen, liquid air, liquid oxygen, liquid argon, liquid hydrogen, liquid helium and a low-temperature refrigerant;

the low-temperature liquid storage tank, the low-temperature liquid pump, the exhaust steam heat regenerator, the low-temperature working medium supercritical gas turbine, the throttle valve and the expansion machine are arranged in the low-temperature liquid storage tank; the low-temperature liquid fuel storage device, the low-temperature equipment or the low-temperature components and the corresponding connecting pipelines are low-temperature resistant materials, including but not limited to austenitic low-temperature steel and ferritic low-temperature steel;

The low-temperature equipment or the low-temperature component and the corresponding connecting pipeline are also wrapped by a heat insulating layer; the thermal insulation layer has good thermal insulation performance, and comprises vacuum thermal insulation, aerogel, foam materials, fiber materials, glass wool and high-silicon cotton;

further, the device also comprises a cold box, wherein the cold box is made of a high-heat-insulation material, and the low-temperature equipment is placed in the cold box; the cold box is also provided with an isolation; the cold box is insulated from the external environment by a highly insulated enclosure, and the insulation is again insulated and isolated from the cryogenic equipment at different temperatures.

10. A supercritical low-temperature working medium cylinder body shaft seal gas turbine device and a process of a using method are suitable for the supercritical low-temperature working medium cylinder body shaft seal gas turbine device and the using method in any one of claims 1 to 9; the method comprises the following steps:

for example, the low-temperature liquid working medium stored in the low-temperature liquid storage tank is liquid nitrogen or liquid air with the boiling point temperature lower than-196 ℃ under the standard atmospheric pressure, the high pressure is added through the low-temperature liquid pump, so that the pressure of the low-temperature liquid power generation working medium reaches more than 3Mpa, the low-temperature liquid power generation working medium flows through a low-temperature pipeline of an exhaust steam regenerator and is conveyed into the main heat exchanger, for example, a hot water heat exchanger with the temperature of more than 50 ℃ is used for heating, and the temperature of nitrogen reaches more; after absorbing the energy of a hot water heat source, the low-temperature liquid nitrogen power generation working medium is gasified to form high-pressure gas, and the high-pressure gas is input and drives the low-temperature working medium supercritical gas turbine to rotate at a high speed to do work; outputting mechanical energy or driving a generator to rotate at a high speed to output electric energy;

The temperature of the dead steam output by the exhaust pipeline of the low-temperature working medium supercritical gas turbine reaches the critical temperature of about-147 ℃ of the liquid nitrogen; condensing high-temperature high-pressure exhaust steam which is output by the low-temperature working medium supercritical turbine and reaches the critical temperature by adopting extremely low-temperature liquid output by a low-temperature liquid pump and liquid nitrogen or liquid air with the temperature lower than-196 ℃; the high-temperature exhaust steam and extremely low-temperature liquid nitrogen or liquid air below minus 196 ℃ fully exchange heat in the exhaust steam heat regenerator; after losing heat energy, the high-temperature and high-pressure exhaust steam reaching the critical temperature is condensed into low-temperature and high-pressure liquid nitrogen or liquid air, and after throttling, pressure reduction and refrigeration are carried out by the throttle valve, the low-temperature and low-pressure liquid nitrogen or liquid air is returned to the low-temperature liquid storage tank for storage and standby;

liquid nitrogen or liquid air stored in the low-temperature liquid storage tank is pressurized by the low-temperature liquid pump at a temperature lower than-196 ℃, is conveyed into a low-temperature pipeline of the exhaust steam heat regenerator to perform sufficient heat exchange with a high-temperature pipeline of the exhaust steam heat regenerator, and absorbs high-temperature high-pressure exhaust steam heat energy which is discharged by a low-temperature working medium supercritical turbine and reaches or approaches to a critical temperature of-147 ℃; the extremely low temperature liquid nitrogen or liquid air output by the low temperature liquid pump absorbs the heat energy of the high temperature exhaust steam reaching or approaching the critical temperature, the temperature is raised to about-150 ℃, and the exhaust steam heat regenerator stores the heat exchange temperature difference of the metal pipe wall at the temperature of more than 0.5 ℃; the low-temperature power generation working medium at about-150 ℃ is conveyed to the main heat exchanger from the low-temperature pipeline outlet of the exhaust steam heat regenerator, if the heat exchange is continued with hot water at about 50 ℃ in a hot water heat exchanger, the temperature of the liquid nitrogen or liquid air low-temperature power generation working medium reaches more than 0 ℃; or the waste heat system or the combustion system heats the high-temperature main heat exchanger to more than 200 ℃ to form high-temperature high-pressure nitrogen or high-pressure air, the high-temperature high-pressure nitrogen or the high-pressure air is input and drives the low-temperature working medium supercritical gas turbine to rotate at a high speed to do work, and mechanical energy is output or a generator is driven to output electric energy; the circulation is continued;

Preferably, the high-pressure exhaust steam reaching or approaching the critical temperature is output by the exhaust pipeline of the low-temperature working medium supercritical gas turbine; an expander is further arranged at an outlet of the high-temperature pipeline of the exhaust steam heat regenerator, a high-pressure fluid is input into an input port of the expander, and liquid nitrogen or liquid air which is low-temperature and low-pressure is returned to the low-temperature liquid storage tank after throttling and pressure reduction are carried out on the high-pressure fluid through the expander;

the large pressure difference exists between the input end and the output end of the expansion machine, so that the expansion machine is driven to rotate at a high speed, and mechanical energy is output or a generator is driven to output electric energy; the expander does work outwards due to high-speed rotation, so that internal energy stored in the low-temperature working medium fluid is consumed, and the temperature of the low-temperature working medium returned to the low-temperature liquid storage tank is lower; the low-temperature liquid working medium in the low-temperature liquid storage tank can be kept at a low temperature, and the low-temperature liquid pump outputs lower-temperature liquid nitrogen or liquid air, so that high-temperature and high-pressure exhaust steam output by the low-temperature working medium supercritical gas turbine is condensed;

further, the low-temperature liquid storage tank is also provided with a cooling device, and the cooling device comprises the low-temperature liquid storage tank, a compressor, a condenser, a second throttling valve or a second expansion machine which are sequentially connected; the expander rotates at a high speed, is coaxially connected with and drives the compressor to rotate at a high speed, and an inlet of the compressor is communicated with the top of the low-temperature liquid storage tank, so that gas evaporated in the low-temperature liquid storage tank is collected and compressed into high-pressure high-temperature gas which is conveyed to the condenser for condensation;

The condenser is arranged between the outlet of the high-temperature pipeline of the exhaust steam heat regenerator and the expander, and releases heat energy generated by the compressor into a low-temperature working medium at the input front end of the expander so as to absorb heat and gasify the low-temperature working medium; inputting and driving the expansion machine to do work, and outputting mechanical energy or driving a generator to output electric energy; the outlet of the condenser is connected with a second expansion valve or a second expansion machine, the low-pressure and low-temperature liquid is returned to the low-temperature liquid storage tank through throttling, pressure reducing and refrigerating of the second expansion valve or the second expansion machine, and the low-temperature power generation working medium in the low-temperature liquid storage tank is cooled continuously through circulation.