CN106150471B - Dock gasification furnace and operating method for coal underground gasifying technology - Google Patents
Dock gasification furnace and operating method for coal underground gasifying technology Download PDFInfo
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- 238000002309 gasification Methods 0.000 title claims abstract description 197
- 239000003245 coal Substances 0.000 title claims abstract description 100
- 238000005516 engineering process Methods 0.000 title claims abstract description 20
- 238000011017 operating method Methods 0.000 title claims description 16
- 238000002347 injection Methods 0.000 claims abstract description 92
- 239000007924 injection Substances 0.000 claims abstract description 92
- 239000000178 monomer Substances 0.000 claims abstract description 62
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 55
- 238000003786 synthesis reaction Methods 0.000 claims abstract description 52
- 238000005553 drilling Methods 0.000 claims abstract description 36
- 238000004458 analytical method Methods 0.000 claims abstract description 10
- 239000007800 oxidant agent Substances 0.000 claims abstract description 8
- 230000001590 oxidative effect Effects 0.000 claims abstract description 8
- 239000007789 gas Substances 0.000 claims description 75
- 238000000034 method Methods 0.000 claims description 59
- 230000008569 process Effects 0.000 claims description 40
- 238000004519 manufacturing process Methods 0.000 claims description 22
- 238000010276 construction Methods 0.000 claims description 16
- 238000012545 processing Methods 0.000 claims description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 11
- 229910052760 oxygen Inorganic materials 0.000 claims description 11
- 239000001301 oxygen Substances 0.000 claims description 11
- 238000013461 design Methods 0.000 claims description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 239000004568 cement Substances 0.000 claims description 6
- 238000011143 downstream manufacturing Methods 0.000 claims description 6
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 5
- 238000010304 firing Methods 0.000 claims description 4
- 238000011084 recovery Methods 0.000 claims description 4
- 238000005065 mining Methods 0.000 claims description 2
- 230000002035 prolonged effect Effects 0.000 claims 2
- 239000000725 suspension Substances 0.000 claims 2
- 238000003032 molecular docking Methods 0.000 claims 1
- 238000009434 installation Methods 0.000 abstract description 2
- 230000008859 change Effects 0.000 description 8
- 230000000903 blocking effect Effects 0.000 description 6
- 238000002485 combustion reaction Methods 0.000 description 5
- 239000011435 rock Substances 0.000 description 5
- 230000008901 benefit Effects 0.000 description 3
- 238000009776 industrial production Methods 0.000 description 3
- 241000209094 Oryza Species 0.000 description 2
- 235000007164 Oryza sativa Nutrition 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 238000005755 formation reaction Methods 0.000 description 2
- 230000003447 ipsilateral effect Effects 0.000 description 2
- 238000003908 quality control method Methods 0.000 description 2
- 235000009566 rice Nutrition 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000011269 tar Substances 0.000 description 2
- FGUUSXIOTUKUDN-IBGZPJMESA-N C1(=CC=CC=C1)N1C2=C(NC([C@H](C1)NC=1OC(=NN=1)C1=CC=CC=C1)=O)C=CC=C2 Chemical compound C1(=CC=CC=C1)N1C2=C(NC([C@H](C1)NC=1OC(=NN=1)C1=CC=CC=C1)=O)C=CC=C2 FGUUSXIOTUKUDN-IBGZPJMESA-N 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 244000208734 Pisonia aculeata Species 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 239000003610 charcoal Substances 0.000 description 1
- 239000011280 coal tar Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000001730 gamma-ray spectroscopy Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
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- 238000004886 process control Methods 0.000 description 1
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/295—Gasification of minerals, e.g. for producing mixtures of combustible gases
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- Mining & Mineral Resources (AREA)
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- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Gasification And Melting Of Waste (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
Abstract
The invention discloses a kind of underground gasification furnaces for coal underground gasifying technology, including at least one dock gasification furnace monomer, the dock gasification furnace monomer includes such as lower component: two orientation injection wells, and each orientation injection well includes that injection casing, concentric setting inject into well bushing pipe and Uuderground Supervision System;Orient the oxidant injection device and underground ignition installation that is fitted with coiled tubing in the internal lining pipe of injection well, can pull back;One confined goods well supervises system table including confined goods casing, the product pipe of concentric setting and underground, and product pipe end is open-celled structure, and the internal lining pipe of whole aperture is equipped in confined goods well horizontal channel;Two orientation injection wells and a confined goods well intersect with each other perforation in tail end, and confined goods well well head is equipped with synthesis gas on-line period analysis system and control system.The configuration of the present invention is simple can reduce drilling cost again using the vertical segment structure for discarded dock gasification furnace injection well of shunting in a well.
Description
Technical field
The invention discloses a kind of underground gasification furnaces and operating method for coal underground gasifying technology.
Background technique
Underground coal gasification(UCG) (ISC) is a kind of controlled burning (imperfect combustion) by subterranean coal and gasified reverse
It answers, coal is converted into the technical process of gas products.Product gas is commonly known as synthesis gas, can be used as fuel production,
The raw material of the downstream processes such as Chemical Manufacture, power generation.The technical process the set complete well of shaft building, underground coal mining and coal gasifying process skill
Art has many advantages, such as that safety is good, investment is small, high efficiency, pollutes less.
Coal seam is led directly to by ground drilling, the injection of oxygen supply agent and product gas output provide effective channel.One is used for
The drilling well of oxidant injection is known as " injection well ", another drilling well for being used to produce product gas is known as " product well ".Orient water
Flat drill well and vertical drilling all can be used as injection well or product well.
When having injection well, product well and horizontal channel to connect the two in coal seam, this construction is referred to as a coal
Charcoal underground gasification (ISC) unit or well pair.ISC unit includes combustion zone, gasification zone and pyrolysis zone.It is raw by underground coal gasification(UCG)
At product gas (crude synthesis gas) usually contain synthesis gas (CO, CO2,H2,CH4Deng) and other impurities ingredient (solid particle,
Water, coal tar, H2S,NH4, COS etc.).Crude synthesis gas is by being delivered to ground through product well, then is transported to downstream by surface line
Device is handled and is applied.
The type selecting of underground gasification furnace needs to comprehensively consider the geology and hydrogeologic condition and downstream process pairing in coal seam
At the requirement etc. of makings amount.Type of furnace design includes the drilling technology used in building process, the position of well pair and purposes etc..It is existing
The various gasification type of furnaces usually only account for " sheet/bulk " exploitation of ideally large area, and have ignored practical operation
The synthesis gas stability as caused by complex geological condition and gasification in the process, technology controlling and process, ground or subsurface formations are heavy
The problems such as drop.For example, the Chinese invention patent application book of Publication No. CN104594873A discloses a kind of underground coal gasification(UCG)
Furnace and gasification process.The gasification furnace includes the injection channel of an Approaching Coal Seam bottom plate, an Approaching Coal Seam top plate outlet passageway
The vertical ignition well with one.It is lighted a fire using vertical well, by being exported after bottom progress combustion gasification through coal seam top.It is main
Technical disadvantages are that the high temperature of the outlet passageway directly acts on roof, be easy to cause the wind of roof deformation, inbreak
Danger.When it carries out the exploitation of extensive furnace group, after lighting a fire in a well, drawn by implementing to fall back in the second gasification unit
Fire, then multiple gasification furnaces of the first gasification unit in parallel.Lighting up procedure auxiliary, the time is longer, and whole system needs to be operated in parallel, certain
, which there is emergency case, in one gasification furnace to be found and handle in time.The Chinese invention patent application book of publication number CN105089604A
Disclose a kind of underground coal gasification furnace and gasification process.The gasification furnace includes a vertical well (product well) and multiple mutual
The structure for the directed drilling composition being parallel to each other on the vertical plane.Entire high seam is carried out using gasification step from the bottom to top
Gasification.For its major technique the disadvantage is that, this method operation control is extremely difficult, easily generation spring layer perforation damages entire gasification
Furnace layout.Upper layer coal seam is preheated using the heat of lower layer's combustion gasification, pre- thermogenetic tar easily blocks horizontal channel and hangs down
The communication port of straight well, meanwhile, warm is not easy to control, and temperature is excessively high or overlong time is easily damaged the support in channel, makes
At upper channel collapsing the problems such as.In conclusion existing underground gasification furnace technology and gasification process become influence coal
One of efficiency of under ground gasification and the bottleneck of stability.The main problem faced at present includes:
(1) positioning of carrying out horizontal directed drilling determines direction mainly by gamma-spectrometry instrument in coal seam at present.Gamma
Measuring instrument can be by the way that in top plate, the decaying rank in bottom plate and coal seam determines its drilling well position, then for distinguishing in coal seam
There are larger difficulties for different drilling well positions.Therefore, the existing gasification type of furnace is (two or more to be mutually on the vertical plane parallel to each other
Directed drilling structure) drilling well difficulty and cost are largely improved, influence heavy industrialization project implementation;
(2) using to it is lower and on gasification process have several defects.First, easily spring layer in underlying seam gasification,
Especially superjacent channel is laid out and in an area of low pressure, or there are air/oxidizers;Second, using lower part
The heat of coal seam gasification preheats superjacent, and the tar that the superjacent of warm generates is easy blocking horizontal channel and production
Product gas exit normal well, while being also easily damaged the support being laid out in channel or other subsurface equipments;Third, if coal seam contains
Water is higher, is easy to be deposited on underlying seam channel, causes extreme difficulties to igniting and gasification process control;4th, coal seam is certainly
The intensity of body is generally more much lower than strength of roof, when implementing underground gasification to lower layer coal seam and forming larger burned out area, top
Coal seam blocks the gasification tunnel of underlying seam since self weight is easy to collapse;5th, need to gasify in underlying seam terminates, closed furnace, people
It could implement superjacent gasification after work filling, and when entirely superjacent channel design already builds up more.When drilling channel is long
Between it is vacant, be easy to appear the blocking of superjacent channel design, destroy, collapse, coal seam aoxidize the problems such as.
(3) entire gasified boiler system relies primarily on only one vertical well outlet passageway, is easy to appear blocking and current limliting
Problem.Secondly as product well is different with the working environment of injection well, interior design and layout also have larger difference.If
Its integrality is easily destroyed as alternate channel using another injection well merely, product gas leakage or underground water is caused to leak
The problems such as.
(4) since whole system shares an outlet passageway, gasification can not independently monitor each injection well just after starting
Normal operational process.Once encounter underground emergency case, can not find in time with appropriate processing, entire gasified boiler system will be unable to after
Continuous normal operating, it is larger to coal resources waste.
(5) after gasifying, since whole system shares an outlet passageway, stopping for subsequent gasification furnace can not properly be implemented
Vehicle, flame-out, cleaning and recovery operation, there are biggish environmentally friendly hidden danger.
Summary of the invention
It is an object of the present invention to solving the deficiencies in the prior art, provide a kind of for coal underground gasifying technology
Underground gasification furnace.
The second object of the present invention is to provide a kind of operation side of underground gasification furnace for coal underground gasifying technology
Method.
The technical solution adopted by the present invention to solve the technical problems is:
For the dock gasification furnace of coal underground gasifying technology, including at least one dock gasification furnace monomer, it is described
Dock gasification furnace monomer includes such as lower component:
Two orientation injection wells, each orientation injection well includes injecting the injection well liner of casing, concentric setting
Pipe and Uuderground Supervision System;
Orient the oxidant injection device and ground down-firing that is fitted with coiled tubing in the internal lining pipe of injection well, can pull back
Equipment;
One confined goods well is supervised system table including confined goods casing, the product pipe of concentric setting and underground, is produced
Quality control end is open-celled structure, and the internal lining pipe of whole aperture is equipped in confined goods well horizontal channel;
Two orientation injection wells and a confined goods well intersect with each other perforation in tail end, confined goods well location in centre,
Two orientation injection wells are located at confined goods well two sides;
Confined goods well well head is equipped with synthesis gas on-line period analysis system and control system.
Preferably, two orientation injection wells are arranged in parallel with the non-transfixion part that intersects of a confined goods well, orientation injection
Parallel distance between well and confined goods well is 10-30 meters.
Preferably, dock gasification furnace includes at least two dock gasification furnace monomers, adjacent dock gasification furnace monomer
Parallel distance between ipsilateral orientation injection well is 20-40 meters, wherein the 10-30 meters of width for prearranged pillar, it is ensured that each
Dock gasification furnace monomer is closed independent operation unit, and each dock gasification furnace monomer is online according to the synthesis gas of itself
Sampling analytical system and control system independent operation ensure the synthesis gas production of continuous-stable.
When the emergency cases such as blocking, flame-out, oxygen leakage occurs in some dock gasification furnace monomer, positioned at the dock
The Uuderground Supervision System and well head synthesis gas on-line period analysis system of gasification furnace monomer can find and feed back in time, be conducive to and
When independently reply handle the dock gasification furnace monomer, minimize various security risks, it is ensured that underground gasification stability and can
By property.
When finding above-mentioned emergency case, spare processing scheme is one side positioning injection well of Temporarily Closed, fixed according to unilateral side
Emergency location is judged to the condition of production of injection well and is handled.
After gasification, the orientation injection well and confined goods well of the new dock gasification furnace monomer of different level can be sharp respectively
It is shunt in a well with a level and discards the orientation injection well and the vertical segment structure of confined goods well of dock gasification furnace monomer, reduce drilling well
Cost.
For high seam gasification, using from top to down the step of, successively gasify, the maximum resource rate of extraction.
The present invention carries out general thickness coal seam (thickness < 20 meter) extensive according to above-mentioned dock gasification furnace monomer
The layout and underground gasification method of industrialized production, including:
A) according to project construction scale, A phase project dock gasification furnace number of monomers n are determined, be followed successively by A1,
A2 ... ... An is laid out according to the parallelism structural of dock gasification furnace monomer.Same dock gasification furnace monomer orientation injection well with
Parallel distance between confined goods well is 10-30 meter, adjacent dock gasification furnace monomer orient between injection well it is parallel away from
From for 20-40 meters (including 10-30 meters of prearranged pillars between dock gasification furnace monomer);
B) in A1 gasification furnace, in two orientation injection well horizontal channels with confined goods well distalmost end intersection
Implement to light a fire simultaneously.Unqualified tail gas is incorporated to ground exhaust pipe, is transported to flare discharge;
C) after lighting a fire successfully, air, oxygen-enriched or pure oxygen gasification process are switched to according to the technological requirements.Synthesis gas quality meets
After design standard, it is incorporated to ground synthesis gas pipeline, is transported to purified synthesis gas processing and downstream syngas comprehensive utilization process;
D) successively to A2, A3 ... An carries out igniting and technique switches to normal production.Unqualified tail gas is incorporated to ground tail
Feed channel is transported to flare discharge.Qualified synthesis gas product is incorporated to ground synthesis gas pipeline, be transported to purified synthesis gas processing and
Downstream syngas comprehensive utilization process;
E) when the consumption of A term area coal seam is close to be finished, start the drilling well of B phase, igniting, gasification in new working face.
Wherein, in B phase process of construction, dock gasification furnace position of the dock gasification furnace position of B phase relative to the A phase will be same
One plane is whole along the distance (10-30 meters) for deviating a prearranged pillar perpendicular to vertical gasification direction.Finally burned out area is
Staggeredly it is intervally arranged, the support force of maximizing prearranged pillar.Later, repeat step a)-d), it is ensured that downstream process it is continuous steady
Fixed operation;
F) reach normal production when the B phase, at the end of the A phase gasifies, successively A1, A2 ... ... An are stopped, stopped working, clearly
It washes and restores.After water quality in burned out area reaches related environmentally friendly prescribed requirement, shut-in well processing is carried out to A phase gasification furnace.Herein, institute
There is well to shunt in a well using cement from bottom to ground;
G) when the consumption of B term area coal seam is close to be finished, step a)-f is repeated), start the C phase, the D phase gasifies until will be entire
Coal seam consumption.
The present invention solves in another embodiment of its technical problem, according to above-mentioned dock gasification furnace, for super thick
Coal seam (thickness > 20 meter) carries out the layout and underground gasification method of large-scale industrial production, including:
A) coal seam is divided into several layers, it can be according to non-texture of coal in every thickness degree most thick 15-20 meters and/or run of mine coal seam
(such as dirt band, vacation top etc.) position divides;
B) according to project construction scale, A phase project gasification furnace number n are determined, L1 layers (top layers) according to above-mentioned general
Logical thickness coal layer underground gasifying furnace layout and method implement above-mentioned general thickness coal seam gasification step a)-g), entire L1 layers is disappeared
Consumption.When stating general thickness coal seam gasification step f on the implementation, all wells are shunt in a well using cement from bottom to overlying rock,
Wherein, it need to be determined the need for implementing artificial caving or artificial filling before shut-in well according to practical geological conditions;
C) when L1 layers of Final Issue regional coal-seam consumption are close to when finishing, beginning is in L2 layers of the drilling well of A phase, igniting, gasification
Process when gasification furnace is built, using the vertical section of orientation injection well and confined goods well of existing A phase L1 layer, starts L2 layers of the A phase
Drilling well and gasification furnace are built, and using L1 layers of burned out area of A phase in drilling process, artificial caving area or artificial fill area are positioning
Boundary, it is ensured that the accuracy and reliability of Directional Drilling, in process of construction, L2 layers of gasification furnace position is relative to L1 layers of gasification furnace
Position needs the distance (10-30 meters) of one prearranged pillar of overall offset, and final burned out area is in vertical plane (different layers) and horizontal plane
(identical layer) is all intervally arranged to interlock, the support force of maximizing prearranged pillar;
D) at the end of L1 layers of Final Issue gasify, above-mentioned general thickness coal seam gasification step a)-g is repeated), by entire L2
Layer consumption;
E) step a)-d is repeated according to the subregion of step a) from top to bottom), entire coal seam is consumed.
Detailed description of the invention
Fig. 1 is dock coal underground gasifying furnace list furnace diagrammatic cross-section;
Fig. 2 is general thickness coal seam dock coal underground gasifying furnace group's schematic layout pattern;
Fig. 3 is ultra-thick coal bed dock coal underground gasifying furnace group's schematic layout pattern.
In figure: 1, injection well, 2, product well, 3, overlying rock, 4, coal seam.
Specific embodiment
In order to make the present invention more be easily understood, it is convenient for practical operation, one or more preferred specific embodiments will join
According to attached drawing, only it is described by way of example.
For the dock gasification furnace of coal underground gasifying technology, including at least one dock gasification furnace monomer, it is described
Dock gasification furnace monomer includes such as lower component:
Two orientation injection wells, each orientation injection well includes injecting the injection well liner of casing, concentric setting
Pipe and Uuderground Supervision System;
Orient the oxidant injection device and ground down-firing that is fitted with coiled tubing in the internal lining pipe of injection well, can pull back
Equipment;
One confined goods well is supervised system table including confined goods casing, the product pipe of concentric setting and underground, is produced
Quality control end is open-celled structure, and the internal lining pipe of whole aperture is equipped in confined goods well horizontal channel;
Two orientation injection wells and a confined goods well intersect with each other perforation in tail end, confined goods well location in centre,
Two orientation injection wells are located at confined goods well two sides;
Confined goods well well head is equipped with synthesis gas on-line period analysis system and control system.
Preferably, two orientation injection wells are arranged in parallel with the non-transfixion part that intersects of a confined goods well, orientation injection
Parallel distance between well and confined goods well is 10-30 meters.
Preferably, dock gasification furnace includes at least two dock gasification furnace monomers, adjacent dock gasification furnace monomer
Parallel distance between ipsilateral orientation injection well is 20-40 meters, wherein the 10-30 meters of width for prearranged pillar, it is ensured that each
Dock gasification furnace monomer is closed independent operation unit, and each dock gasification furnace monomer is online according to the synthesis gas of itself
Sampling analytical system and control system independent operation ensure the synthesis gas production of continuous-stable.
When the emergency cases such as blocking, flame-out, oxygen leakage occurs in some dock gasification furnace monomer, positioned at the dock
The Uuderground Supervision System and well head synthesis gas on-line period analysis system of gasification furnace monomer can find and feed back in time, be conducive to and
When independently reply handle the dock gasification furnace monomer, minimize various security risks, it is ensured that underground gasification stability and can
By property.
When finding above-mentioned emergency case, spare processing scheme is one side positioning injection well of Temporarily Closed, fixed according to unilateral side
Emergency location is judged to the condition of production of injection well and is handled.
After gasification, the orientation injection well and confined goods well of the new dock gasification furnace monomer of different level can be sharp respectively
It is shunt in a well with a level and discards the orientation injection well and the vertical segment structure of confined goods well of dock gasification furnace monomer, reduce drilling well
Cost.
For high seam gasification, using from top to down the step of, successively gasify, the maximum resource rate of extraction.
Horizontal channel length of the injection well in coal seam is oriented up to 500-1500 meters, preferably 800-1200 meters.Orientation note
Enter well include inject casing, the orientation of concentric setting injects into well bushing pipe, is mounted on and injects into well bushing pipe liner pipe outer wall
Uuderground Supervision System.Wherein injection casing extends to the bottom position parallel with seat earth since ground
It sets.Inject into well bushing pipe and select complete pipe, be consumables, ordinary carbon steel pipe can be selected in material, and seamless steel pipe engages steel pipe
Deng.Inject into well bushing pipe and selects open-celled structure from ignition location to its top (with product well intersection).The aperture of aperture is 5-
35mm, aperture are laid out with the interval mode that interlocks, and the aperture gross area accounts for the 5-35% of tube wall area.Uuderground Supervision System includes temperature
Degree, pressure and sonic sensor, extend to its top along injecting into well outside bushing pipe.
Inject into well the oxidant injection device and underground ignition installation that is equipped with coiled tubing in bushing pipe, can pull back, uses
In subterranean coal igniting, the normal injection for producing required oxidant and gasifying agent and the control of gasification process process, it is ensured that high
The steady production of quality synthesis gas.
Confined goods well, including product casing, the product pipe of concentric setting, Uuderground Supervision System table.Wherein orient
Freely-suspended product pipe end horizontal position is open-celled structure in product well, and the internal lining pipe in confined goods well horizontal channel is
Whole open-celled structure, the aperture of aperture are 5-35mm, and aperture is laid out with the interval mode that interlocks, and the aperture gross area accounts for tube wall area
5-35%.
Synthesis gas on-line period analysis system is mounted on product well exit, monitors single gasification furnace synthesis gas for independent
Quality and oxygen content, and timely feedback to control system and security system, it is ensured that the safety of entire gasification process, stability and
Reliability.
According to geology conditional decision, the prearranged pillar between dock gasification furnace monomer is 10-30 meters, to ensure each gas
It is mutually isolated between change furnace monomer, it is independent operation unit.Burned out area is preferably staggeredly intervally arranged inside final coal seam, can be maximum
Change the support force of prearranged pillar.
Dock gasification furnace monomer burned out area width is controllable, with specific reference to gasification furnace monomer operating pressure, coal seam thickness, gas
Change the resistance to compression stretching resistance of furnace heat transference efficiency, coal seam and its overlying rock, the factors such as stability of synthesis gas quality determine.Generally
Situation is 2-6 times, about 20-80 meters, preferably 30-60 meters of coal seam thickness.
Parallel distance between same dock gasification furnace monomer orientation injection well and confined goods well is 10-30 meters, phase
Parallel distance between adjacent dock gasification furnace orientation injection well is 20-40 meters (including the prearranged pillar between gasification furnace monomer
10-30 meters).
In first embodiment of the invention, dock gasification furnace monomer as shown in Figure 1, dock gasification furnace monomer by two
A orientation injection well 1 and a confined goods well 2 form.Upper overlying strata are run through using directed drilling and completion technique in predetermined position
Layer 3 extends into coal seam 4 and forward 500-1500 meters, construction confined goods well 2 and complete well.It is placed in 2 end of confined goods well
Signal projector guides injection well directed drilling.Start injection well orientation at 2 well head of confined goods well, two lateral extent 10-30 rice
Drilling well ensures itself and confined goods well 2 through into coal seam 4 and forward 500-1500 meters of the extension of overlying rock 3 in drilling process
In parallel.It is guided according to the signal projector of 2 end of confined goods well, so that two orientation injection wells 1 are being held with confined goods well 2
Intersect and penetrate through each other in portion.In orientation injection well horizontal segment end (i.e. tail end intersection) while implementing to light a fire, after lighting a fire successfully,
Air, oxygen-enriched or pure oxygen gasification process are switched to according to the technological requirements.When synthesis gas quality be lower than design standard after or burned out area
After width reaches design requirement, pullback operation is implemented to note oxygen equipment simultaneously in two injection well well heads, by combustion zone and gasification
Area is moved to fresh coal seam, produces the synthesis gas of high quality.It dashes forward when blocking, flame-out, oxygen leakage etc. occurs in some gasification furnace
Heat condition, Uuderground Supervision System and well head synthesis gas on-line period analysis system positioned at gasification furnace can find and handle in time.
Meanwhile can one side positioning injection well of Temporarily Closed, emergency location is judged according to the unilateral condition of production and is handled.
Another embodiment of the invention, as shown in Fig. 2, using the dock gasification furnace monomer to general thickness coal seam
The layout and operating method of (thickness < 20 meter) progress large-scale industrial production.Specific implementation method is as follows: first, according to item
Mesh production scale determines A phase project gasification furnace number n, is laid out according to the parallelism structural of dock underground gasification furnace.Same gas
Changing the parallel distance between furnace injection well and product well is 10-30 meters, and the parallel distance between adjacent gasification furnace injection well is 20-
40 meters (including 10-30 meters of prearranged pillar between gasification furnace);Second, in A1 gasification furnace, with product well distalmost end phase
Implement to light a fire simultaneously in two injection well horizontal channels at friendship.Unqualified tail gas is incorporated to ground exhaust pipe, is transported to torch
Discharge;Third after lighting a fire successfully, switches to air, oxygen-enriched or pure oxygen gasification process according to the technological requirements.Synthesis gas quality meets
After design standard, it is incorporated to ground synthesis gas pipeline, is transported to purified synthesis gas processing and downstream syngas comprehensive utilization process;The
Four, igniting successively is carried out to A2, A3 ... ... An and technique switches to normal production.Unqualified tail gas is incorporated to ground exhaust pipe,
It is transported to flare discharge.Qualified synthesis gas product is incorporated to ground synthesis gas pipeline, is transported to purified synthesis gas processing and downstream is closed
At gas comprehensive utilization process;5th, when the consumption of A term area coal seam is close to be finished, start the drilling well of B phase, point in new working face
Fire, gasification.Wherein, in B phase process of construction, gasification furnace position of the gasification furnace position of B phase relative to the A phase will be same
One plane is whole along the distance (10-30 meters) for deviating a prearranged pillar perpendicular to gasification furnace direction.Final burned out area is staggeredly
It is intervally arranged, the support force of maximizing prearranged pillar.Later, step 1 is repeated to four, it is ensured that the continuous-stable of downstream process
Operation;6th, reach normal production when the B phase, at the end of the A phase gasifies, successively A1, A2 ... ... An is stopped, stopped working, clearly
It washes and restores.After water quality in burned out area reaches related environmentally friendly prescribed requirement, shut-in well processing is carried out to A phase gasification furnace.Herein, institute
There is well to shunt in a well using cement from bottom to ground;7th, when the consumption of B term area coal seam is close to be finished, repeat step 1
To six, start the C phase, the D phase gasifies until entire coal seam is consumed.
Another embodiment of the invention, as shown in figure 3, using the dock gasification furnace to ultra-thick coal bed (thickness > 20
Rice) carry out large-scale industrial production layout and operating method.Specific implementation method is as follows: first, if coal seam is divided into
Dried layer can be divided according to texture of coal non-in every thickness degree most thick 15-20 meters and/or run of mine coal seam (such as dirt band, vacation top etc.) position;The
Two, according to project construction scale, A phase project gasification furnace number n are determined, L1 layers (top layers) according to above-mentioned general thickness coal
Layer underground gasification furnace layout and method (Fig. 2) implement above-mentioned general thickness coal seam gasification step 1 to seven, and entire L1 layers is consumed.
When stating general thickness coal seam gasification step 6 on the implementation, all wells are shunt in a well using cement from bottom to overlying rock.Its
In, it need to be determined the need for implementing artificial caving or artificial filling before shut-in well according to practical geological conditions;Third, when L1 layers most
Latter term area coal seam consumption is close to when finishing, and beginning is in L2 layers of the drilling well of A phase, igniting, gasification.When gasification furnace is built,
Using the vertical section of existing A phase L1 layer injection well and product well, start L2 layers of the drilling well of A phase and gasification furnace construction.Drilling process
In using L1 layers of burned out area of A phase, artificial caving area or artificial fill area are positioning boundary, it is ensured that the accuracy of Directional Drilling and
Reliability.In process of construction, L2 layers of gasification furnace position needs one reserved coal of overall offset relative to L1 layers of gasification furnace position
The distance (10-30 meters) of column.Final burned out area is all intervally arranged in vertical plane (different layers) and horizontal plane (identical layer) to interlock,
The support force of maximizing prearranged pillar;4th, at the end of L1 layers of Final Issue gasify, repeat above-mentioned general thickness coal bed gas
Change step 1 to seven, entire L2 layers is consumed;5th, this method is repeated according to the subregion of this method step 1 from top to bottom
Step 1 consumes entire coal seam to four.
In conclusion dock gasification furnace of the invention has the advantage that 1. structures are simple, new dock gasification furnace orientation
Injection well can reduce drilling cost again using the vertical segment structure for discarded dock gasification furnace injection well of shunting in a well;2. effectively
Dock gasification furnace length is extended, extends the service life of dock gasification furnace, improves the economic benefit of project;3. dock gas
The possibility for the problems such as change furnace burned out area width is controllable, implements longwell/band-like exploitation, minimizes roof inbreak or formation subsidence
Property;4. each dock gasification furnace monomer is closed separate unit, is individually operated and controlled, any one dock
Gasification furnace monomer does not influence the normal production of dock gasification furnace group when something goes wrong, it is ensured that the safety of synthesis gas production, steady
Qualitative and continuity;5. the ignition process of each dock gasification furnace monomer can be implemented step by step, ignition phase is significantly reduced not
The discharge amount of qualified tail gas;6. burned out area structure is simple, no dead angle, the parking after gasification, flame-out, cleaning and recovery operation
It can implement step by step, it is safe and simple.
" embodiment " mentioned above is included in correlation properties, structure described in embodiment, feature
It is all related to wherein at least one embodiment of the invention.Therefore, described above repeatedly to refer to " in an embodiment "
Not all refer in particular to the same embodiment in place.In addition, the correlation properties described in embodiments, structure, feature can be with
The combination of any suitable way one or more.
The foregoing is merely the preferred embodiments of the invention, are not intended to restrict the invention.For this field
Technical staff, the present invention can have various change and change.All within the spirits and principles of the present invention, that is done any repairs
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.
Claims (9)
1. a kind of operating method of the dock gasification furnace for coal underground gasifying technology, based on common within 20 meters of thickness
Thickness coal seam, the dock gasification furnace include at least one dock gasification furnace monomer, the dock gasification furnace monomer packet
It includes such as lower component:
Two orientation injection wells, it is each orientation injection well include inject casing, concentric setting inject into well bushing pipe and
Uuderground Supervision System;
The oxidant injection device and ground down-firing for orienting in the internal lining pipe of injection well and being mounted on coiled tubing, can pull back are set
It is standby;
One confined goods well, product pipe, Uuderground Supervision System including confined goods casing, concentric setting, product pipe
By well mouth hanger free suspension, it is greater than zero after maximum heat prolonged expansion at a distance from confined goods bottom, product pipe end
End is open-celled structure, and the internal lining pipe of whole aperture is equipped in confined goods well horizontal channel;
Prearranged pillar between two orientation injection wells and a confined goods well, and intersect with each other perforation in tail end, confined goods
Well location is located at confined goods well two sides in centre, two orientation injection wells;
Confined goods well well head is equipped with synthesis gas on-line period analysis system and control system;
It is characterized by: the operating method is as follows:
A) according to project construction scale, A phase project dock gasification furnace number of monomers n are determined, the An that is followed successively by A1, A2 ... ...,
It is laid out according to the parallelism structural of dock underground gasification furnace monomer, same dock gasification furnace monomer orientation injection well and directional produced
Parallel distance between product well is 10-30 meters, and the parallel distance between adjacent dock gasification furnace monomer orientation injection well is 20-
40 meters;
B) in A1 gasification furnace, in two orientation injection well horizontal channels with confined goods well distalmost end intersection simultaneously
Implement igniting, unqualified tail gas is incorporated to ground exhaust pipe, is transported to flare discharge;
C) after lighting a fire successfully, air, oxygen-enriched or pure oxygen gasification process are switched to according to the technological requirements, and synthesis gas quality meets design
After standard, it is incorporated to ground synthesis gas pipeline, is transported to purified synthesis gas processing and downstream syngas comprehensive utilization process;
D) igniting successively is carried out to A2, A3 ... ... An and technique switches to normal production, unqualified tail gas is incorporated to ground tail gas
Pipeline is transported to flare discharge, and qualified synthesis gas product is incorporated to ground synthesis gas pipeline, be transported to purified synthesis gas processing and under
Swim synthesis gas comprehensive utilization process;
E) when the consumption of A term area coal seam is close to be finished, start the drilling well of B phase, igniting, gasification in new working face, wherein
In B phase process of construction, dock gasification furnace position of the dock gasification furnace position of B phase relative to the A phase will be in same plane
It is whole that along the prearranged pillar distance for deviating one 10-30 meters perpendicular to vertical gasification direction, burned out area is staggeredly to be intervally arranged,
To maximize the support force of prearranged pillar, later, step a)-d is repeated), it is ensured that the continuous and steady operation of downstream process;
F) reach normal production when the B phase, at the end of the A phase gasifies, successively A1, A2 ... ... An are stopped, stop working, cleaned
And recovery carries out shut-in well processing to A phase gasification furnace after water quality in burned out area reaches related environmentally friendly prescribed requirement, herein, owns
Well is shunt in a well using cement from bottom to ground;
G) when the consumption of B term area coal seam is close to be finished, step a)-f is repeated), start the C phase, the D phase gasifies until by entire coal seam
Consumption.
2. a kind of operating method of the dock gasification furnace for coal underground gasifying technology, common greater than 20 meters based on thickness
Thickness coal seam, the dock gasification furnace include at least one dock gasification furnace monomer, the dock gasification furnace monomer packet
It includes such as lower component:
Two orientation injection wells, it is each orientation injection well include inject casing, concentric setting inject into well bushing pipe and
Uuderground Supervision System;
The oxidant injection device and ground down-firing for orienting in the internal lining pipe of injection well and being mounted on coiled tubing, can pull back are set
It is standby;
One confined goods well, product pipe, Uuderground Supervision System including confined goods casing, concentric setting, product pipe
By well mouth hanger free suspension, it is greater than zero after maximum heat prolonged expansion at a distance from confined goods bottom, product pipe end
End is open-celled structure, and the internal lining pipe of whole aperture is equipped in confined goods well horizontal channel;
Prearranged pillar between two orientation injection wells and a confined goods well, and intersect with each other perforation in tail end, confined goods
Well location is located at confined goods well two sides in centre, two orientation injection wells;
Confined goods well well head is equipped with synthesis gas on-line period analysis system and control system;
It is characterized by: the operating method is as follows:
A) coal seam is divided into several layers, is drawn according to non-texture of coal position in every thickness degree most thick 15-20 meters and/or run of mine coal seam
Point;
B) according to project construction scale, A phase project gasification furnace number n is determined, is grasped by the following method in the L1 layer of top layer
Make, entire L1 layers consumed:
B1) according to project construction scale, A phase project dock gasification furnace number of monomers n is determined, is followed successively by A1, A2 ... ...
An is laid out according to the parallelism structural of dock underground gasification furnace monomer, and same dock gasification furnace monomer orients injection well and determines
It is 10-30 meters to the parallel distance between product well, the parallel distance between adjacent dock gasification furnace monomer orientation injection well
It is 20-40 meters;
B2 same in two orientation injection well horizontal channels with confined goods well distalmost end intersection) in A1 gasification furnace
When implement igniting, unqualified tail gas is incorporated to ground exhaust pipe, is transported to flare discharge;
B3 after) lighting a fire successfully, air, oxygen-enriched or pure oxygen gasification process are switched to according to the technological requirements, synthesis gas quality, which meets, to be set
After meter standard, it is incorporated to ground synthesis gas pipeline, is transported to purified synthesis gas processing and downstream syngas comprehensive utilization process;
B4 igniting successively) is carried out to A2, A3 ... ... An and technique switches to normal production, unqualified tail gas is incorporated to ground tail gas
Pipeline is transported to flare discharge, and qualified synthesis gas product is incorporated to ground synthesis gas pipeline, be transported to purified synthesis gas processing and under
Swim synthesis gas comprehensive utilization process;
B5) when the consumption of A term area coal seam is close to be finished, start the drilling well of B phase, igniting, gasification in new working face,
In, in B phase process of construction, dock gasification furnace position of the dock gasification furnace position of B phase relative to the A phase will be same
Plane is whole along the prearranged pillar distance for deviating one 10-30 meters perpendicular to vertical gasification direction, and burned out area is staggeredly to be spaced
Arrangement later, repeats step b1 to maximize the support force of prearranged pillar)-b5), it is ensured that the continuous-stable of downstream process is transported
Row;
B6) reach normal production when the B phase, at the end of the A phase gasifies, successively A1, A2 ... ... An are stopped, stop working, cleaned
And recovery carries out shut-in well processing to A phase gasification furnace after water quality in burned out area reaches related environmentally friendly prescribed requirement, herein, owns
Well is shunt in a well using cement from bottom to ground;
B7) when the consumption of B term area coal seam is close to be finished, step b1 is repeated)-b6), start the C phase, the D phase gasifies until will be entire
L1 layers of consumption coal seam consumption;
C) when L1 layers of Final Issue regional coal-seam consumption are close to when finishing, beginning is lighted a fire, gasification in L2 layers of the drilling well of A phase,
When gasification furnace is built, using the vertical section of orientation injection well and confined goods well of existing A phase L1 layer, start L2 layers of the drilling well of A phase
And gasification furnace is built, using burned out area, artificial caving area or the artificial fill area of A phase L1 floor to position boundary in drilling process,
Ensure the accuracy and reliability of Directional Drilling, in process of construction, L2 layers of dock gasification furnace monomer sites are relative to L1 layers
The prearranged pillar distance of one 10-30 meters of dock gasification furnace monomer sites overall offset, final burned out area hang down different layers
It faces directly with the horizontal plane of identical layer in being staggeredly intervally arranged, to maximize the support force of prearranged pillar;
D) at the end of L1 layers of Final Issue gasify, repeat the above steps b1)-b7), until entire L2 layers is consumed;
E) step a)-d is repeated according to the subregion of step a) from top to bottom), entire coal seam is consumed.
3. the operating method of the dock gasification furnace according to claim 1 or 2 for coal underground gasifying technology, special
Sign is: two orientation injection wells are arranged in parallel with the non-transfixion part that intersects of a confined goods well, orientation injection well and orientation
Parallel distance between product well is 10-30 meters, and the parallel distance between the orientation injection well of adjacent docking gasification furnace monomer is
20-40 meters.
4. the operating method of the dock gasification furnace according to claim 1 or 2 for coal underground gasifying technology, special
Sign is: the coal column of certain size is reserved between each dock gasification furnace monomer, width is 10-30 meters, it is ensured that each right
Connecing formula gasification furnace monomer is closed independent operation unit, and each dock gasification furnace monomer takes online according to the synthesis gas of itself
Sample analysis system and control system independent operation ensure the synthesis gas production of continuous-stable.
5. the operating method of the dock gasification furnace according to claim 1 or 2 for coal underground gasifying technology, special
Sign is: orienting injection well and product well length is 500-1500 meters.
6. the operating method of the dock gasification furnace according to claim 5 for coal underground gasifying technology, feature
It is: orients injection well and product well length is 800-1200 meters.
7. the operating method of the dock gasification furnace according to claim 1 or 2 for coal underground gasifying technology, special
Sign is: the burned out area width range of dock gasification furnace monomer is at 20-80 meters.
8. the operating method of the dock gasification furnace according to claim 7 for coal underground gasifying technology, feature
Be: the burned out area width range of dock gasification furnace monomer is at 30-60 meters.
9. the operating method of the dock gasification furnace according to claim 4 for coal underground gasifying technology, feature
Be: prearranged pillar is staggeredly to be intervally arranged, and to maximize prearranged pillar to the support force of entire mining area, avoids formation subsidence
Or surface subsidence problem.
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