CN1230659A - Plasma ignitor for direct ignition of power station duff boiler - Google Patents
Plasma ignitor for direct ignition of power station duff boiler Download PDFInfo
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Abstract
The plasma ignitor consists of burner, plasma emitting gun and power source. The burner is wholly DC one developed by utilizing reasonable pneumatic arrangement method and the plasma emitting gun is developed high-temperature and high-pressure one. The present invention solves the problem existing in igniting low-grade coal by plasma ignitor, and can be used stably in power station duff boiler burning low grade coal.
Description
The invention discloses a plasma ignition device for directly igniting a pulverized coal boiler of a power station, which is mainly used for directly igniting the pulverized coal boiler of the power station including lean coal and is used for stabilizing combustion when the peak load operation of the power station is carried out.
At present, fuel oil is adopted to start ignition in the ignition modes of domestic and foreign power station boilers, for example, power stations in China, the ignition oil is started by 180 ten thousand tons every year, which is converted into RMB (more than 50 hundred million yuan), and in addition, the peak regulation of large-capacity units is also imperative along with the increasing of the capacity of a power grid and the capacity of a single machine in the power industry in China. The peak regulation of the power grid generally adopts three modes, namely a two-shift system is adopted, namely the power grid is stopped at 22 o 'clock at night and started at 6 o' clock in the morning; secondly, a low-load stable combustion mode is adopted (the mode is adopted in China, and the main purpose is to overcome the serious damage to equipment caused by frequent start and stop), and the low-load stable combustion index is that oil feeding is adopted for combustion supporting when the load of a boiler using lean coal is below 50%; the third way is to establish a large-scale energy storage hydropower station to solve the problem of power consumption in the valley of power consumption, but the third way must be realized by taking measures to the whole range of billions of yuan of huge amount of resources.
In the face of the worldwide energy crisis, particularly in the poor oil country, the invention of the oil for ignition starting and low-load stable combustion of the utility boiler in a non-traditional way is urgently needed. The method not only accords with the instruction spirit of the traffic energy department of the design and commission in 97 years 'Chinese energy', the China is a country with abundant coal resources and relatively short petroleum resources, the substitution of coal for oil is a very important energy policy, the research, development, popularization and application of the technology and the product of substituting coal for oil are part of the long-term energy strategy being executed, and the method has obvious economic and social benefits for the energy band of China and has important significance for the energy conservation all over the world.
The use of high temperature plasma to solve the above problems began as early as the sixties. The American C-E company, the B-W company, the West House company, the original Soviet Union, the Australian Pacific International electric Power company, the Qinghua university of China, the Halbinboiler plant, the Wuhan boiler plant and other units make great contribution to the research. Since the eighties, they have continued to complete laboratory and industrial tests using plasma technology to directly ignite coal dust. In 1995, the international power company in the pacific australia successfully completed the manufacture of commercial products on a 30-ten-thousand-watt power station boiler, but the fuel used by the products was high-quality coal with a volatile content of more than 25%, while most of China burned lean coal, so the products were not suitable for China. In the end of 1995, the plasma ignition device for the power station pulverized coal boiler, which is invented by the original soviet union, directly ignites lean coal in copper and Sichuan with 13% of volatile matter and 4775 kilocalories per kilogram of heat value in our country's Bao chicken power plant, but only normally operates for zero eighths of three hours, namely, the device is damaged and stops working, the plasma emission device cannot reliably work in the high-temperature and high-pressure environment for a long time, and particularly cannot reliably work on the plasma ignition device for directly igniting the power station pulverized coal boiler for a long time, the electrode has the problems of core digging, slag falling and unstable current in the combustion process, an insulating layer (cooler) made of bakelite is broken down at high temperature to cause short circuit, and the problems of multiple loosening of water, electricity and gas joints, multiple faults and the like occur; the volute burner is adopted to feed powder, and the defects of severe burning red of the volute, coking on the wall surface, severe abrasion, short service life and the like exist.
The invention aims to provide a plasma ignition device for directly igniting a pulverized coal boiler of a power station, which can be stably applied to the pulverized coal boiler of the power station including direct ignition of inferior coal for a long time.
The purpose of the invention is realized as follows: a plasma ignitor for directly igniting the powdered coal boiler in power station is composed of a burner with secondary air pipeline, primary air pipeline for delivering main powdered coal, high-temp steam pipeline, primary air powder pipeline, plasma jet tube, which is fixed to the front end of said primary air powder gun tube and is arranged in said secondary air pipeline.
The front end of the pipeline for conveying the high-temperature steam is closed, the front end of the pipeline for conveying the high-temperature steam is provided with a steam guide hole, and the total area of the steam guide holes is approximately equal to the annular end area of the pipeline for conveying the high-temperature steam; when the volatile content of the coal is higher, the pipeline for conveying high-temperature steam can be removed;
the front end of the pipeline for conveying the secondary air is closed, secondary air guide holes are formed in the front end of the pipeline for conveying the secondary air, and the total area of the secondary air guide holes is approximately equal to the annular end area of the pipeline for conveying the secondary air;
the plasma emission gun is provided with an electrode, a conductive mounting seat, a conductive tube, a conductive gasket, an insulating material, a shell, a bare head wire and an anti-loosening joint, wherein the shell is provided with an air inlet pipe; cooling through holes can be formed in the conductive mounting seat and the electrode;
wherein, the insulating material filled between the conductive tube and the shell is a group of high-alumina insulating ceramic tubes or high-alumina insulating ceramic tubes sintered with high-temperature glaze;
the electrode is made of hafnium, zirconium or silicon-molybdenum, is fixed in the conductive sleeve to form a combined electrode, and is detachably fixed on the conductive mounting seat;
wherein, the insulating material filled among the conductive gasket, the bare conductor and the shell is a high-temperature resistant rubber insulating bush;
the anti-loosening joint is composed of an outer nut, a joint, a base plate and a spring, the spring is arranged between the joint and the base plate, an anti-loosening spring clip is fixed at the end of the outer nut, one end of the joint penetrates through the outer nut, the other end of the joint is propped against the base plate of the pushing high-aluminum insulating ceramic tube, a thread is arranged at the tail end of the shell, a circle of tooth-shaped groove is formed in the position, corresponding to the anti-loosening spring clip, of the lower end of the thread, and a bare conductor penetrates through the joint, the base plate.
The main advantages of the invention are:
as is known, the inferior coal is mainly characterized by high ash content (more than 50 percent), high moisture content, low calorific value and low ash melting point; the boiler using such coal has problems of poor combustion characteristics, delayed ignition, unstable combustion, reduced thermal efficiency, insufficient output, etc.; the problem with high ash content is that the heating surfaces become fouled, reducing the availability of the equipment. The invention adopts a method of reasonably arranging pneumatic layout, invents a full-direct-current burner and a high-temperature high-pressure plasma emission gun, and solves the problems existing in burning inferior coal.
1. The plasma ignition device of the invention has the following cost comparison with the traditional fuel oil system:
unit capacity (ten thousand kilowatts) 10203050
Required oil system equipment cost (ten thousand yuan) 60080010001200
Using plasma ignition means (stage) 4688
Using plasma ignition means
Required cost (ten thousand yuan) 200300400400
Cost saving (ten thousand yuan) 400500600800
2. The plasma ignition device of the invention compares the cost with the conventional fuel oil system:
according to the calculation of data at the end of 1997, the total installed capacity of thermal power generating units of the national power system is as follows: 1.88 hundred million kilowatts, estimated to 940 standard 20 kilowatt units; the oil system of the 20-ten thousand kilowatt unit is two layers of 8 oil guns, the output of a single oil gun is 1.5 tons/hour, and the following estimation is carried out:
A. the oil for ignition and stable combustion in the national electric power system is about 150-180 ten thousand tons/year, and the comprehensive cost is 45-54 million yuan RMB/year according to 3000 yuan/ton;
by adopting the plasma ignition device, the cost of coal consumption is only about 12 percent of the cost of oil consumption, and the cost is about 5.4 to 6.5 million yuan RMB/year; the cost is saved by 39.6 to 47.5 hundred million yuan RMB/year;
B. the plasma ignition device disclosed by the invention has the following effects in power grid peak regulation:
with the increasing of the power grid capacity and the single unit capacity in China, the peak regulation of a large-capacity unit is imperative, the problem of low valley power consumption of the power grid is still a subject concerned by people in the world, and the remarkable advantages of the invention can be seen after the estimation aiming at the national conditions in China:
(1) peak shaving was achieved using a two shift system: (frequent start in this way, which would significantly reduce the life of the equipment)
The method comprises the following steps that 50% of full power generation and 50% of peak shaving are carried out in China, namely 20-point shutdown is carried out, the power generation is carried out at 6:00 in the morning of the next day, and the power generation is carried out at 8:00, namely 470 units of 20 ten thousand kilowatts work for 300 days in a year;
estimating the oil consumption cost: q1=57.7 billion yuan/year
By adopting the plasma ignition device, the coal consumption cost is as follows: q2=6.77 billion/year
Electricity consumption cost: q3=0.388 yen/year
The ratio of the cost of adopting the oil to the cost of adopting the invention is as follows:
(q2+q3)/q1=12%
the energy-saving cost is as follows: q1-q2-q3=50.6 yen/year;
the above estimate is essentially the same as the national statistics of 54 billion dollars per year.
(2) Power grid peak regulation with low load steady burning (this way is good for protecting the equipment)
The specification requires that the load is thrown to 30% at every 22 o 'clock, a layer of 4 multiplied by 1.5 tons/hour oil gun is thrown at the moment, the oil gun is started at 6 o' clock in the morning, the oil gun is fully distributed according to 50% in the whole country, the peak load is regulated according to 50%, and 470 machines calculate:
estimating the oil consumptioncost: q1=203 billion/year
By adopting the plasma ignition device, the coal consumption cost is as follows: q2=27 billion/year
Electricity consumption cost: q3=1 billion/year
The ratio of the cost of adopting the oil to the cost of adopting the invention is as follows:
(q2+q3)/q1=14%
the energy-saving cost is as follows: q1-q2-q3=175 billion/year
(3) Cost recovery case:
a adopts a two-shift system, which is the recovery cost of 2 months;
and B, low-load operation is adopted, and the recovery cost is 1 month.
3. Because the burner in the plasma ignition device adopts full-direct-current coaxial step-by-step control type pneumatic layout, an aviation Laval nozzle and a boundary layer gas film cooling technology are used, a step-by-step speed flow field is established to ensure that step-by-step entrainment and mixing are realized and a large temperature drop zone is formed in the burner, so that the whole combustion process is finished in a specified pneumatic flow field, the wall surface temperature of the burner is ensured not to reach the melting point of ash, in addition, the primary air powder cannot collide and rub the wall surface of the burner by utilizing the isolation action of an inner gas film, and therefore, particularly when lean coal is used, the plasma ignition device can successfully and directly ignite the lean coal and support and stably combust at low load; the wall surface of the burner is not coked, the abrasion is small, the service life is long, the powdery fuel is fully and stably combusted, the price is low, and the like.
4. The plasma emission gun insulation material adopts high-alumina ceramics and is sintered with high-temperature glaze, so that the whole emission gun cannot be broken down at high temperature; the problem that the original Soviet Union adopts bakelite insulation and is punctured for several times at high temperature is solved;
because the electrode of the plasma emission gun is made of refractory metal zirconium or hafnium and the like, the metal evaporation amount is extremely small under the condition of high temperature and large current, in addition, a plurality of through holes are drilled in the cylindrical electrode, all high-speed air carriers are changed into plasma after the electrode is cooled, the service life of the ignition gun is greatly prolonged, and a series of defects caused by the adoption of a graphite electrode in the original Soviet Union product are overcome;
the conductive mounting seat of the electrode can be disassembled and replaced, the use is very convenient, and the problem that the electrode of the charged transmission polished rod is unsafe is avoided;
the conductive path of the emission gun adopts a conductive tube and a conductive sleeve to send current of 200-600 amperes from a rectifying device to an electrode ignition end, and forms high-temperature (4000-5000 ℃) electric arc with an anode spray tube, and simultaneously, cold air from an air inlet pipe cools the whole conductive path and the electrode through an air inlet hole, a pipe core and a cooling through hole, so that the problem that the oxidation of the electrode is accelerated at high temperature by adopting the outer surface of an air-cooled electrode in the original Soviet Union is solved;
the anti-loosening spring clip fixed on the outer nut is rotated to a position, and the clip just falls into the tooth-shaped groove, so that a good anti-loosening effect is achieved; the problem of the ordinary screwed joint of former soviet union design, become flexible many times, leak water,leak gas and can not use in the course of the work is solved.
FIG. 1 is a schematic view of a burner structure of the plasma ignition device according to the present invention;
FIG. 2 is a schematic view of a plasma torch structure of the plasma ignition device according to the present invention;
FIG. 3 is a schematic view of a plasma ignition device according to the present invention.
The invention will be further illustrated by the following examples in conjunction with the accompanying drawings
Example 1:
a plasma ignition device for directly igniting a pulverized coal boiler of a power station comprises a plasma burner, an emission gun and a power supply;
the DC power supply supplies current to the emission gun, the electric arc emitted by the emission gun changes air or inert gas into plasma arc, the plasma arc directly ignites the coal powder in the burner, and the burner continuously sends the coal to the hearth, thereby achieving the purpose of warming the furnace.
As shown in FIG. 1, the burner has a pipeline 4 for conveying secondary air, a pipeline 7 for conveying primary coal powder flow, a pipeline 9 for conveying high-temperature steam, a pipeline 11 for conveying primary air powder for ignition, a pipe 12 for containing a plasma emission gun, and an anode plasma nozzle 6;
the pipeline 4 for conveying secondary air, the primary air pipeline 7 for conveying main pulverized coal flow, the pipeline 9 for conveying high-temperature steam and the pipeline 11 for conveying primary air powder for ignition are all annular pipelines;
the end of the pipeline 4 for conveying secondary air is connected with the primary air pipe 3 for conveying main pulverized coal flow through an annular baffle 13, the end of the primary air pipeline 7 for conveying main pulverized coal flow is connected with the pipe 8 for conveying high-temperature steam through the annular baffle 13, the end of the pipeline 9 for conveying high-temperature steam is connected with the pipe 10 for conveying ignition primary pulverized coal through the annular baffle 13, the end of the pipeline 11 for conveying ignition primary pulverized coal is connected with the pipe 12 internally provided with a plasma ignition source through the annular baffle 13, and the concrete connection can adopt a screw fastening connection mode, namely, all pipelines are sequentially coaxially sleeved and fixedly installed into an integral structure according to a step type;
the secondary air pipe 2 is provided with a secondary air F2 inlet, the primary air pipe 3 for conveying the main pulverized coal flow is provided with a primary air F1 inlet for the main pulverized coal flow, the pipe 8 for conveying high-temperature steam is provided with a high-temperature steam Fh inlet, and the pipe 10 for conveying the primary air powder for ignition is provided with a primary air powder Fd1 inlet;
the front end of the pipeline 9 for conveying high-temperature steam is sealed by a baffle (or the front end of the pipeline is sealed by adopting a conical structure), a plurality of rows of steam guide holes 5 vertical to the axial line are uniformly drilled on the inner ring of the front end, and the total area of all the annular guide holes is approximately equal to the annular end area of the pipeline 9 for conveying high-temperature steam, so that the flow resistance of gas is reduced; under the condition of high volatile content of coal, the high-temperature steam pipeline can be removed;
or the front end of the pipeline 9 for conveying high-temperature steam is not closed, a diversion hole is not formed, and the purpose of inhibiting expansion can be achieved by changing the pressure of the steam;
the front end of the pipeline 4 for conveying secondary air is sealed by a baffle (or the front end of the pipeline is sealed by adopting a conical structure), a plurality of rows of secondary air diversion holes 1 vertical to the axis are uniformly drilled on the inner ring of the front end, and similarly, the total area of all the circumferential diversion holes is approximately equal to the circumferential end area of the pipeline 4 for conveying secondary air, so that the flowing resistance of air is reduced;
or the front end of the pipeline 4 for conveying secondary air is not closed, no diversion hole is formed, and the secondary air F2 can be used for inhibiting the expansion of flame and preventing the coking of coal powder on the wall surface of the combustor by changing the pressure of the secondary air;
the anode plasma jet tube 6 is a jet tube which converges and diffuses firstly, the material can be red copper, the red copper is cooled by adopting a conventional water cooling mode, and the anode plasma jet tube is fixed at the front end of a tube 12 internally provided with a plasma emission gun; or the edge of the plasma spray pipe 6 is provided with a circle of annular holes through which the primary air powder can flow, and the spray pipe 6 is fixedly welded on a pipe 10 for conveying the primary air powder for ignition.
As shown in fig. 2, the gun has an electrode 14, a conductive mounting base 16, a fastening sleeve 17, a conductive tube 18, a contact point, a lead 27, a check joint 28, a ceramic insulating tube 21, a gasket 19, an insulating bush 24, a shell 20 and an air inlet pipe 23;
the electrode 14 is fixedin the conductive sleeve 15 to form a combined electrode (the conductive sleeve 15 is made of high conductive material, such as copper pipe), the electrode 14 is made of refractory metal hafnium, zirconium, molybdenum and the like, a plurality of cooling through holes 33 are drilled in the cylindrical micro-loss electrode according to the air flow, the conductive mounting seat 16 is also provided with the cooling through holes 33 (or the electrode is drilled with the cooling through holes 33, the conductive mounting seat 16 is not provided with the cooling through holes 33, or the electrode is not drilled with the cooling through holes 33, the conductive mounting seat 16 is provided with the cooling through holes 33), and high-speed air from the air inlet pipe 23 is cooled by the counter electrode to become plasma;
the conductive tube 18 is a copper tube, which is provided with a cold air inlet 32, the shell 20 is provided with an air inlet pipe 23, and the air inlet pipe 23 can be welded on the shell 20; cold air enters the conductive tube core from the air inlet pipe 23 through the air inlet hole 32 and is discharged from the cooling through hole 33, so that the whole gun body conductive passage and the electrode are cooled;
the combined electrode is fixed on the conductive mounting seat 16 through a screw (or other detachable fixing modes), the conductive mounting seat 16 and the fastening sleeve 17 can be in screw or threaded connection, the conductive tube 18 is arranged in the shell 20, one end of the conductive tube is welded on the fastening sleeve 17, the other end of the conductive tube is connected with the front contact point 22 and the rear contact point 29 through a conductive gasket 31, the bare conductor 27 is welded on the rear contact point 29 and is locked and fixed by the anti-loosening joint 28;
a high-temperature-resistant insulating material is filled between a conductor formed by sequentially connecting the conductive tube 18, the conductive gasket 31 and the bare conductor 27 and the shell 20, the high-temperature-resistant insulating material is an annular high-alumina ceramic insulating tube 21 (the gun is ensured to have a resistance of not less than 3000V at a high temperature of 800 ℃) with high-temperature glaze sintered, a group of ceramic insulating tubes 21 are mutually sleeved, a gasket 19 can be added at a gap for fixing, the shell 20 is ensured to be uncharged, and an insulator filled among the conductive gasket 31, the bare conductor 27 and the shell 20 can also be an insulating rubber bushing 24;
the anti-loosening joint 28 consists of an outer nut 25, a joint 26, a backing plate 34 and a spring 35, wherein the spring 35 is arranged between the joint 26 and the backing plate 34, and a group of anti-loosening spring clips 30 are welded at the end head of the outer nut 25;
the tail end of the shell 20 is provided with a thread, and the lower end of the thread is provided with a circle of tooth-shaped grooves corresponding to the anti-loosening spring clips 30;
when the anti-loose joint 28 is installed at the tail end of the shell 20 and the external screw cap 25 is screwed, the joint 26 tightly pushes against the backing plate 34, so as to extrude the high-alumina ceramic insulating tube 21, the front contact point and the rear contact point are tightly pressed and tightly contacted with the conductive tube 18, so that the whole conductive path is connected, and after the anti-loose joint is screwed in place, the anti-loose spring clip 30 at the tail end of the shell 20 is just clamped in the tooth-shaped groove at the end part of the shell 20 and cannot be loosened.
The working principle and the process of the invention are as follows:
as shown in figure 3, the plasma ignition device of the invention is used for directly igniting a power station pulverized coal boiler containing lean coal, and is directly arranged in a secondary air pipe of the boiler or on the outer wall of the boiler, a burner secondary air pipeline 4 of the plasma ignition device is firstly connected with a prefabricated pipe of a boiler wall, a primary air pipeline 7 for conveying main pulverized coal flow, a pipeline 9 for conveying high-temperature steam, a pipeline 11 for conveying ignition primary air powder and a pipe 12 of a plasma emission gun provided with a spray pipe 5 are connected into a whole, a sleeve 36 is inserted into the pipe 12, and finally the plasma emission gun is fastened in the sleeve 36 in a threaded connection mode, so that the whole installation process is completed;
high-capacity current (such as 200-600 amperes) from the rectifying device is sent to a firing end (shown in figure 2) through a wire 27 on a plasma emission gun through a contact point, a conductive tube 18, a conductive mounting seat 16 and a conductive sleeve 15 on an electrode, a gap between the electrode 14 and a spray pipe 6 is punctured by a 25000-volt high-frequency coil to form an electric arc, the electric arc is blown into a combustor I area by pressure cold air or inert gas from an air inlet pipe 23, and the air or the inert gas is mixed with the electric arc to form a plasma arc; the divergent expansion at the mouth of the nozzle 6 is in a reverse cone shape (the reverse cone flame is very beneficial to ignition), the expanded reverse cone flame is restrained by the primary air powder Fd1 for ignition output by the pipeline 11 (the expansion of the plasma flame can be controlled by adjusting the total pressure of the primary air powder in the pipeline 11);
when the volatile components of the primary air powder for ignition are ignited by the plasma flame, secondary expansion is carried out again, and the expansion flow is also inhibited by high-temperature steam Fh output from the pipeline 9 ring to the steam guide hole 5 (similarly, the expansion of the volatile components of the air powder can be controlled by adjusting the total pressure of the steam in the pipeline 9, and the temperature in the whole combustor can be controlled).
The burning wind powder volatile matter is ignited again to the main coal powder flow F1 sent by the pipeline 7, and the secondary expansion flow is restrained by the secondary wind F2 sent from the pipeline 4 to the secondary wind diversion hole 1; if the front end of the duct 4 for conveying the secondary air is not closed, the expansion flow is directly restrained by the secondary air F2 output from the duct 4 (similarly, the expansion can be controlled by adjusting the total pressure of the secondary air in the duct 4);
the high-temperature steam Fh flowing in the duct 9 and the secondary air F2 flowing in the duct 4 can suppress the expansion of the flame and form a large temperature drop zone in the wall surface of the burner. The formation mechanism is as follows: when the gas in the pipe flows to the end of the pipeline, the gas is blocked by the closed baffle plate, the dynamic pressure is reduced, the static pressure is increased, the gas is forced to flow out from the boundary layer diversion hole, the combustor is cooled, a large temperature drop area is formed, the temperature of the combustor is far lower than the melting point of the ash content of the pulverized coal, in addition, the primary air powder is not close to the wall surface of the combustor due to the influence of vertical flow, and the coking is inhibited.
In the above-mentioned process, plasma arc ignites the wind-powder mixture of primary wind of ignition coal powder in zone I, and in zone II the thermochemical treatment (coal gasification) is completed, i.e. (ii) a And igniting the volatile component of the main pulverized coal in the zone III, and converging the volatile component of the main pulverized coal and secondary air to be pushed into a hearth to be burnt out. The whole continuous combustion process completes the temperature rise of the boiler.
Although the structure is complicated, the power of a rectifying starting power supply of the plasma igniter can be greatly reduced, and the service life of the device is prolonged.
The flame stabilizing mechanism of the burner is that the air is changed into plasma flow by utilizing the electrolytic ionization process of electric arc, in addition, the added chemical heat treatment process of coal is equal to the increase of the amount of volatile components (CO + H2) required in the combustion process, the ignition heat supply is improved, and a stable ignition source is established, so that the flame formed by the plasma arc, the volatile components of the coal and the CO + H2 with high heat value obtained by the chemical heat treatment of the coal establishes a two-high one-low torch region, namely a high-temperature, high-speed and low-pressure plasma flow torch region, and the central low-pressure region realizes the entrainment and mixing effect of two 'primary air powder' and creates a good flame stabilizing condition. The designed combustor adopts a full direct current pneumatic layout and a four-layer stepped velocity flow field, wherein two layers are main flow fields, namely ignition primary air and main pulverized coal primary air; the two layers are control flow fields, namely steam and secondary air; the combustion of the two expansion flows is controlled within a specified range by the forced compression action of steam and secondary air in the two layers of control flow fields, so that the technical difficulties of 'wall brushing' friction, coking and the like in the pulverized coal combustion process are solved.
Claims (10)
1. A plasma ignition device for directly igniting a pulverized coal boiler of a power station comprises a burner, a plasma emission gun and a power supply, and is characterized in that: the burner is provided with a pipeline (4) for conveying secondary air, a primary air pipeline (7) for conveying main pulverized coal flow, a pipeline (9) for conveying high-temperature steam, a pipeline (11) for conveying primary air powder for ignition, a pipe (12) internally provided with a plasma emission gun and a plasma spray pipe (6), wherein the pipelines are sequentially coaxial, stepped, internally contracted and fixedly installed into an integral structure, the plasma spray pipe (6) is a spray pipe which is converged firstly and then diffused, the plasma spray pipe (6) is fixed at the front end of the pipe (12) internally provided with the plasma emission gun, and the plasma emission gun is arranged in the pipeline (12) internally provided with the plasma emission gun.
2. The plasma ignition device for directly igniting a pulverized coal boiler of a power plant as claimed in claim 1, characterized in that: the front end of a pipeline (9) for conveying high-temperature steam is closed, a steam guide hole (5) is formed in the front end of the pipeline (9) for conveying high-temperature steam, and the total area of the steam guide hole (5) is approximately equal to the annular end area of the pipeline (9) for conveying high-temperature steam.
3. The plasma ignition device for directly igniting a pulverized coal boiler of a power plant as claimed in claim 2, characterized in that: the front end of the pipeline (4) for conveying secondary air is closed, the front end of the pipeline (4) for conveying secondary air is provided with a secondary air diversion hole (1), and the total area of the secondary air diversion hole (1) is approximately equal to the annular end area of the pipeline (4) for conveying secondary air.
4. A plasma ignition device for direct ignition of a pulverized coal boiler of a power plant according to claim 1, 2 or 3, characterized in that: the pipe (9) for conveying the high-temperature steam is removed.
5. A plasma ignition device for direct ignition of a pulverized coal boiler of a power plant according to claim 1, 2 or 3, characterized in that: the plasma emission gun comprises an electrode (14), a conductive mounting seat (16), a conductive tube (18), a conductive gasket (31), an insulating material (21), a shell (20), a bare-end lead (27) and a check joint (28), an air inlet pipe (23) is arranged on the shell (20), an air inlet hole (32) is formed in the conductive pipe (18), a cooling through hole (33) is formed in the conductive mounting seat (16) or the electrode (14), the air inlet pipe (23) is communicated with the air inlet hole (32) and the cooling through hole (33), the electrode (14) is connected with the conductive mounting seat (16), the conductive pipe (18), the conductive gasket (31) and the bare head wire (27) are sequentially connected and mounted in the shell (20), insulating materials (21) are filled between the conductive pipe (18) and the bare head wire (27), the front end of the conductive pipe (18) is connected with the conductive mounting seat (16), the tail end of the shell (20) is connected with an anti-loosening joint (28), and the bare head wire (; or the conductive mounting seat (16) and the electrode (14) are both provided with cooling through holes (33).
6. The plasma ignition device for directly igniting a pulverized coal boiler of a power plant as claimed in claim 4,characterized in that: the plasma emission gun comprises an electrode (14), a conductive mounting seat (16), a conductive tube (18), a conductive gasket (31), an insulating material (21), a shell (20), a bare-end lead (27) and a check joint (28), an air inlet pipe (23) is arranged on the shell (20), an air inlet hole (32) is formed in the conductive pipe (18), a cooling through hole (33) is formed in the conductive mounting seat (16) or the electrode (14), the air inlet pipe (23) is communicated with the air inlet hole (32) and the cooling through hole (33), the electrode (14) is connected with the conductive mounting seat (16), the conductive pipe (18), the conductive gasket (31) and the bare head wire (27) are sequentially connected and mounted in the shell (20), insulating materials (21) are filled between the conductive pipe (18) and the bare head wire (27), the front end of the conductive pipe (18) is connected with the conductive mounting seat (16), the tail end of the shell (20) is connected with an anti-loosening joint (28), and the bare head wire (; or the conductive mounting seat (16) and the electrode (14) are both provided with cooling through holes (33).
7. The plasma ignition device for directly igniting a pulverized coal boiler of a power plant as claimed in claim 5, characterized in that: the insulating material (21) filled between the conductive tube (18) and the shell (20) is a group of high-alumina insulating ceramic tubes or high-alumina insulating ceramic tubes sintered with high-temperature glaze.
8. The plasma ignition device for directly igniting a pulverized coal boiler of a power plant as claimed in claim 7, characterized in that: the electrode (14) is made of hafnium, zirconium or silicon-molybdenum, and the electrode (14) is fixed in the conductive sleeve (15) to form a combined electrode.
9. The plasma ignition device for directly igniting a pulverized coal boiler of a power plant as claimed in claim 8, characterized in that: the insulating material (21) filled between the conductive gasket (31), the bare conductor (27) and the shell (20) is a high-temperature resistant rubber insulating bush (24).
10. The plasma ignition device for directly igniting a pulverized coal boiler of a power plant as claimed in claim 9, characterized in that: the anti-loosening joint (28) is composed of an outer nut (25), a joint (26), a base plate (34) and a spring (35), the spring (35) is arranged between the joint (26) and the base plate (34), an anti-loosening spring clip (30) is fixed at the end of the outer nut (25), the joint (26) penetrates through the outer nut (25) to be propped against the base plate (34) of the pushing high-aluminum insulating ceramic tube, the tail end of the shell (20) is provided with a thread, a circle of tooth-shaped groove is formed in the position, corresponding to the anti-loosening spring clip (30), of the lower end of the thread, a bare-head lead (27) penetrates through the joint (26), the base plate (34) and the high-aluminum insulating ceramic tube.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN 98100983 CN1230659A (en) | 1998-03-31 | 1998-03-31 | Plasma ignitor for direct ignition of power station duff boiler |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN 98100983 CN1230659A (en) | 1998-03-31 | 1998-03-31 | Plasma ignitor for direct ignition of power station duff boiler |
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CN1230659A true CN1230659A (en) | 1999-10-06 |
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CN 98100983 Pending CN1230659A (en) | 1998-03-31 | 1998-03-31 | Plasma ignitor for direct ignition of power station duff boiler |
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN100585279C (en) * | 2006-05-10 | 2010-01-27 | 中国科学技术大学 | Coal powder ignition device and method |
RU2498159C1 (en) * | 2012-05-17 | 2013-11-10 | Открытое акционерное общество "Сибтехэнерго" - инженерная фирма по наладке, совершенствованию технологий и эксплуатации электро-энергооборудования предприятий и систем | Method to burn pulverised fuel |
CN107246607A (en) * | 2017-07-06 | 2017-10-13 | 山西大学 | A kind of automatic stable burning system for Process In A Tangential Firing |
WO2020015082A1 (en) * | 2018-07-16 | 2020-01-23 | 卢驭龙 | Electric heating apparatus and electric flame cooker |
-
1998
- 1998-03-31 CN CN 98100983 patent/CN1230659A/en active Pending
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN100585279C (en) * | 2006-05-10 | 2010-01-27 | 中国科学技术大学 | Coal powder ignition device and method |
RU2498159C1 (en) * | 2012-05-17 | 2013-11-10 | Открытое акционерное общество "Сибтехэнерго" - инженерная фирма по наладке, совершенствованию технологий и эксплуатации электро-энергооборудования предприятий и систем | Method to burn pulverised fuel |
CN107246607A (en) * | 2017-07-06 | 2017-10-13 | 山西大学 | A kind of automatic stable burning system for Process In A Tangential Firing |
CN107246607B (en) * | 2017-07-06 | 2023-05-30 | 山西大学 | Automatic stable combustion system for four-corner tangential boiler |
WO2020015082A1 (en) * | 2018-07-16 | 2020-01-23 | 卢驭龙 | Electric heating apparatus and electric flame cooker |
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