Summary of the invention
The objective of the invention is to overcome the deficiency that prior art exists; Can the compressed-air actuated heat energy and the pressure of gas turbine can be reclaimed and provide a kind of; For air separation unit system oxygen improves heat and cold, thereby reduce the consumption of integrated gasification combined cycle for power generation system, realize energy recycle; So that practice thrift cost and power, reduce the IGCC gas turbine compressed air that utilizes of air separation unit system oxygen energy consumption and produce the method and the device of oxygen.
The objective of the invention is to accomplish through following technical scheme; A kind of device that utilizes IGCC gas turbine compressed air to produce oxygen; Which comprises at least one mainly by the raw air compressor; Cooling, purification unit; The air separation unit that the rectifying column that main heat exchanger and mesolow double tower and main condenser are formed constitutes, it comprises that also one can draw the compressed-air actuated gas turbine group compressor of one combustion gas, one can said combustion gas compressed air and the normal temperature nitrogen that comes out from air separation unit be carried out heat exchange preceding heat exchanger; Be provided with one in the main heat exchanger in the air separation unit and supply the leading portion heat exchanger channels of combustion gas compressed air entering; This leading portion heat exchanger channels is provided with the high-temperature turbine decompressor of a band generator of a connection on the top of main heat exchanger; Combustion gas compressed air outlet on this high-temperature turbine decompressor is connected in the back segment heat exchanger channels in the main heat exchanger again, and the outlet of said back segment heat exchanger channels is communicated with air that the raw air compressor comes and converges behind the runner or directly be communicated with and insert in the medium pressure column of rectifying column.
Be provided with between heat exchanger and the main heat exchanger before described that a pair of combustion gas compressed air carries out that purifying anhydrates to remove, the purification unit of carbon dioxide and hydrocarbon impurity.
After supercooling, purification unit, divide at least after the described raw air compressor and be connected to two road raw airs; First via raw air connects a High-Pressure Compressor through piping; The supercharger that connects a cryogenic turboexpander after through first cooler with pipeline; The supercharger outlet is connected to second cooler, connects main heat exchanger through pipeline afterwards; Bifurcated picks out branch line connection cryogenic turboexpander at the middle part of said main heat exchanger, inserts afterwards in the medium pressure column of said rectifying column; Also insert directly or indirectly in the medium pressure column of said rectifying column and directly pick out a pipeline from the bottom from main heat exchanger;
The second road raw air is through directly or indirectly inserting in the medium pressure column of said rectifying column behind the second road raw air runner of said main heat exchanger.
A kind of method of utilizing IGCC gas turbine compressed air to produce oxygen, this method is: utilize compressed-air actuated heat energy of IGCC gas turbine and pressure ability, be used for air separation unit and produce high pressure oxygen, it comprises following several steps:
1) draws one compressed air from the gas turbine group compressor; Wherein at least a portion is through a preceding heat exchanger, and the dirty nitrogen of normal temperature that comes out with air separation unit carries out heat exchange, and dirty nitrogen temperature is risen; Compressed air is cooled to normal temperature, thereby has realized the recovery of compressed air heat energy;
2) compressed air heat energy reclaims the continued purifying, anhydrates through removing after the purification unit, sends into the empty main heat exchanger that divides ice chest behind carbon dioxide and the hydrocarbon impurity;
3) after compressed air is guided to main heat exchanger; Extract out from the top of main heat exchanger; The high-temperature turbine decompressor that is sent to a band generator then expand step-down and cooling, the high-temperature turbine decompressor drives generator for electricity generation through mechanical couplings, thereby has realized the recovery of compressed air pressure energy;
4) compressed air after the cooling continues to carry out heat exchange with the adverse current body in main heat exchanger; Thereby further cooling; The raw air that comes with the air separation unit air compressor converges in the rectifying column medium pressure column that gets in the ice chest, as a part of raw air of air separation unit.
5) described rectifying column forms Double-Tower Structure by a medium pressure column and a lower pressure column through the main condenser connection; Pass through main condenser; Medium pressure column provides the evaporation of lower pressure column bottom liquid to produce the heat of rising steam; And cold that lower pressure column provides the condensation of medium pressure column top nitrogen to produce phegma has been realized the separation of oxygen, nitrogen in double tower; Obtain liquid oxygen at lower pressure column, after liquid oxygen compressed through at least one liquid oxygen pump, re-heat was vaporized normal temperature as the high pressure oxygen product in main heat exchanger.
The present invention comes from described air separation unit air compressor as another part raw air of air separation unit, and the air compressor raw air of said air separation unit is divided into following two parts:
Part raw air is delivered to a High-Pressure Compressor and is compressed, and introduces the main heat exchanger and the body heat exchange back cooling of backflowing afterwards, uses a high pressure throttling arrangement then, sends into the bottom of medium pressure column after the throttling;
The raw air of remainder is introduced main heat exchanger and also is cooled with the fluid thermal exchange of backflowing, and also sends into the bottom of medium pressure column afterwards, participates in the rectifying in the medium pressure column.
The compressed air of gas turbine unit has a large amount of heat energy and pressure can; The IGCC air separation unit is produced high pressure oxygen need consume a large amount of electric energy; The object of the present invention is to provide a kind of apparatus and method that can make full use of compressed-air actuated heat energy of IGCC gas turbine and pressure ability; It has less specific energy consumption and produces hyperbaric oxygen with respect to prior art, and other system of IGCC is not disturbed and influence; It has fully recycled a large amount of heat energy and the pressure abilities of compressed air of IGCC system, thereby reduces the cost that air separation unit is produced high pressure oxygen, can obtain high pressure oxygen economically.
The specific embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is done further detailed description.Shown in Figure 2; A kind of device that utilizes IGCC gas turbine compressed air to produce oxygen of the present invention; Which comprises at least one mainly by the raw air compressor, cooling, purification unit, the air separation unit that the rectifying column that main heat exchanger and mesolow double tower and main condenser are formed constitutes;
It also comprises: have one can draw the preceding heat exchanger 37 that the compressed-air actuated gas turbine group compressor 31, of one combustion gas can carry out heat exchange with said combustion gas compressed air and the normal temperature nitrogen that comes out from air separation unit; Be provided with one in the main heat exchanger in the air separation unit and supply the leading portion heat exchanger channels of combustion gas compressed air entering; This leading portion heat exchanger channels is provided with the high-temperature turbine decompressor 41 of a band generator of a connection on the top of main heat exchanger; Combustion gas compressed air outlet on this high-temperature turbine decompressor 41 is connected in the back segment heat exchanger channels in the main heat exchanger again, and the outlet of said back segment heat exchanger channels is communicated with air that the raw air compressor comes and converges behind the runner or directly be communicated with and insert in the medium pressure column of rectifying column.
Be provided with between heat exchanger 37 and the main heat exchanger before described that a pair of combustion gas compressed air carries out that purifying anhydrates to remove, the purification unit 39. of carbon dioxide and hydrocarbon impurity
After supercooling, purification unit, divide at least after the raw air compressor 2 of the present invention and be connected to two road raw airs; First via raw air connects a High-Pressure Compressor 13 through piping; The supercharger 16 that connects a cryogenic turboexpander after through first cooler with pipeline; Supercharger 16 outlets are connected to second cooler, connect main heat exchanger 20 through pipeline afterwards; Bifurcated picks out branch line connection cryogenic turboexpander 22 at the middle part of said main heat exchanger 20, inserts afterwards in the medium pressure column of said rectifying column; Also insert directly or indirectly in the medium pressure column of said rectifying column and directly pick out a pipeline from the bottom from main heat exchanger 20;
The second road raw air is through directly or indirectly inserting in the medium pressure column of said rectifying column behind the second road raw air runner of said main heat exchanger.
A kind of method of utilizing IGCC gas turbine compressed air to produce oxygen, this method is: utilize compressed-air actuated heat energy of IGCC gas turbine and pressure ability, be used for air separation unit and produce high pressure oxygen, it comprises following several steps:
1) draws one compressed air 35 from gas turbine group compressor 31; Wherein at least a portion is through a preceding heat exchanger; The dirty nitrogen of normal temperature that comes out with air separation unit carries out heat exchange; Dirty nitrogen temperature is risen, and compressed air is cooled to normal temperature, thereby has realized the recovery of compressed air heat energy;
2) compressed air heat energy reclaims the continued purifying, anhydrates through removing after the purification unit, sends into the empty main heat exchanger 20 that divides ice chest behind carbon dioxide and the hydrocarbon impurity;
3) after compressed air is guided to main heat exchanger 20; Extract out from the top of main heat exchanger 20; The high-temperature turbine decompressor that is sent to a band generator then expand step-down and cooling; The high-temperature turbine decompressor drives generator for electricity generation through mechanical couplings, thereby has realized the recovery of compressed air pressure energy;
4) compressed air after the cooling continues to carry out heat exchange with the adverse current body in main heat exchanger; Thereby further cooling; The raw air that comes with the air separation unit air compressor converges in the rectifying column medium pressure column that gets in the ice chest, as a part of raw air of air separation unit.
5) described rectifying column forms Double-Tower Structure by a medium pressure column and a lower pressure column through the main condenser connection; Pass through main condenser; Medium pressure column provides the evaporation of lower pressure column bottom liquid to produce the heat of rising steam; And cold that lower pressure column provides the condensation of medium pressure column top nitrogen to produce phegma has been realized the separation of oxygen, nitrogen in double tower; Obtain liquid oxygen at lower pressure column, after liquid oxygen compressed through at least one liquid oxygen pump, re-heat was vaporized normal temperature as the high pressure oxygen product in main heat exchanger.
Another part raw air as air separation unit of the present invention comes from described air separation unit air compressor, and the air compressor raw air of said air separation unit is divided into following two parts:
Part raw air is delivered to a High-Pressure Compressor and is compressed, and introduces the main heat exchanger and the body heat exchange back cooling of backflowing afterwards, uses a high pressure throttling arrangement then, sends into the bottom of medium pressure column after the throttling;
The raw air of remainder is introduced main heat exchanger and also is cooled with the fluid thermal exchange of backflowing, and also sends into the bottom of medium pressure column afterwards, participates in the rectifying in the medium pressure column.
Embodiment:
The present invention utilizes compressed-air actuated heat energy of IGCC gas turbine and pressure can produce high pressure oxygen; In which comprises at least/and the hot-air-turbine decompressor of low pressure double tower, band generator, High-Pressure Compressor, Cryogenic air turbo-expander, main heat exchanger, high pressure choke valve and connect pipeline.
Draw one about 400 ℃ from gas turbine blower 31, the compressed air 35 of 1.3MPa (absolute pressure) is guided to heat exchanger 37.In heat exchanger 37, compressed air 1 carries out heat exchange with the dirty nitrogen of normal temperature that air separation unit comes out, and dirty nitrogen temperature rises to about 200 ℃, and compressed air is cooled to normal temperature, thereby has realized the recovery of compressed air heat energy.
Compressed air is introduced purification unit 39 through pipeline 38 then, in purification unit, compressed air is purified, and removes to anhydrate, send into main heat exchanger 20 through pipeline 40 behind carbon dioxide and the hydrocarbon impurity.
After compressed air 40 is guided to main heat exchanger 20; Extract out from the top of main heat exchanger 20; The high-temperature turbine decompressor 41 that is sent to a band generator then expands and is depressured to 0.5~0.6MPa (absolute pressure), preferred 0.55MPa (absolute pressure), and compressed air expands in the high-temperature turbine decompressor and cools to-60~-80 ℃; The high-temperature turbine decompressor drives generator 42 generatings through mechanical couplings, thereby has realized the recovery of compressed air pressure energy.
Compressed air 43 after the cooling continues and the exchange of adverse current body heat at main heat exchanger 20, is cooled to dew-point temperature, and the air (23,27) that comes with the air separation unit air compressor converges entering medium pressure column 29, as 25% raw air of air separation unit.
75% raw air is provided by the air 1 of air compressor 2 compression normal temperature and pressures.Raw air is incorporated into air cooling compressor 4 through pipeline 3 and is cooled to 15~20 ℃, preferred 17 ℃.Guide to the molecular sieve adsorber (8,9) of one group of alternation through pipeline 6, by the absorption of the adsorbent of molecular sieve of the inside remove anhydrate, impurity such as carbon dioxide and hydrocarbon.
The molecular sieve adsorber of alternation (8,9) whenever switched at a distance from 4~8 hours and uses container, and preferred 6 hours, regeneration of a job.The regenerating molecular sieve heating and temperature control is at 170~200 ℃, and regeneration gas is the waste gas 30 that air separation unit comes out.
Raw air 11 parts are guided to High-Pressure Compressor 13 through pipeline 12 and are compressed to 4.0~5.0 MPa (absolute pressure), preferred 5.0MPa (absolute pressure).Cooling back 14 is compressed to supercritical pressure 6.0~7.5 MPa (absolute pressure) through the supercharger 16 that pipeline 15 is incorporated into cryogenic turboexpander then, and cooling back 18 is sent to main heat exchanger 20 through pipeline 19.
Part pressure-air is extracted out from the middle part of main heat exchanger 20, is sent to cryogenic turboexpander 22 through pipeline 21.Through after the expansion of cryogenic turboexpander 22, air cooling-down is to bubble point temperature, converges entering medium pressure column 29 with other raw air (23,43).
The part pressure-air is cooled to dew-point temperature after exchanging with the body heat of backflowing in addition, extracts out from the bottom of main heat exchanger 20, is sent to a high pressure throttling arrangement 25 through pipeline 24, sends into the bottom of medium pressure column 29 after the throttling.
Wherein, the high pressure throttling arrangement can be a choke valve, also can be liquid expander, the preferred liquid decompressor.With respect to choke valve, liquid expander can reduce the irreversible loss of air separation unit.
Raw air 11 parts get into main heat exchanger 20 through pipeline 27, exchange and are cooled to the fluid thermal of backflowing and introduce medium pressure column 29 after the dew-point temperature.Medium pressure column 29 belongs to stripping tower, and volatile components oxygen, argon do not concentrate in the middle and lower part of medium pressure column 29, and volatile components nitrogen concentrates at the top of medium pressure column 29.
Medium pressure column 29 connects the formation Double-Tower Structure with lower pressure column 50 through main condenser 61; Through main condenser 61; Medium pressure column 29 provides the evaporation of lower pressure column 50 bottom liquids to produce the heat of rising steam; And cold that lower pressure column 50 provides medium pressure column 29 top nitrogen condensations to produce phegma 52 has been realized the separation of oxygen, nitrogen in double tower.The bottom of lower pressure column 50 obtains the liquid oxygen of at least 99.6% (V/V) purity; The liquid oxygen 46 of drawing from the bottom of lower pressure column 50; Introduce main heat exchanger 20 through High Pressure Liquid Oxygen Pump 45 compression backs, vaporize normal temperature as high pressure oxygen product 60 with the drag flow fluid thermal exchange of main heat exchanger.
Dirty nitrogen 57 is extracted at the top of lower pressure column 50 out, after main heat exchanger 20 re-heats, gets into heat exchange gas 37 through pipeline 59 and heats up, and gets into molecular sieve adsorber (8,9) through pipeline 30 then and regenerates.
The refrigeration of this device is through cryogenic turboexpander 22 and high-temperature turbine decompressor 41 common realizations.The low temperature nitrogen decompressor provides-177~-170 ℃ low temperature cold; High-temperature turbine decompressor 41 provides-60~-80 ℃ high temperature cold.
The foregoing description only is a preferred implementation of the present invention, for utilizing IGCC gas turbine compressed air production hyperbaric oxygen device of air, can make various modification or optimization, and these also are protection scope of the present invention.
The conventional air device is produced 1Nm
3The consumption of/h hyperbaric oxygen pneumoelectric is 0.6 kilowatt. hour, the present invention produces 1Nm
3The consumption of/h hyperbaric oxygen pneumoelectric is 0.45 kilowatt. hour, be 75% of conventional air device production hyperbaric oxygen pneumoelectric consumption.Patent of the present invention if can be applied, and will obtain great economic benefit.