阅读说明：本技术 煤气化系统及水煤浆提浓方法 (Coal gasification system and coal water slurry concentration method ) 是由 王向龙 李克忠 高明 付伟贤 彭知顺 刘刚 侯祥生 刘雷 于 2020-05-29 设计创作，主要内容包括：本发明涉及煤气化技术领域,提供了一种煤气化系统及水煤浆提浓方法。包括制浆及输送单元、添加剂破除单元、水分分离单元、气化炉及水分收集罐,所述制浆及输送单元包括顺次连接的磨煤机、煤浆罐及煤浆给料泵,所述煤浆给料泵与所述添加剂破除单元连接,所述添加剂破除单元用于破坏添加剂的结构,所述水分分离单元用于将破除了添加剂结构的水煤浆中的水分分离,所述添加剂破除单元与所述水分分离单元连接,所述水分分离单元设置有出水口及出煤口,所述出水口与所述水分收集罐连接,所述出煤口与所述气化炉连接；提升水煤浆浓度,避免大量水进入气化炉内蒸发占用气化炉内的热量,从而避免额外耗能维持气化炉内的温度,节约了水煤浆气化成本。(The invention relates to the technical field of coal gasification, and provides a coal gasification system and a coal water slurry concentration method. The coal slurry additive crushing and conveying device comprises a coal mill, a coal slurry tank and a coal slurry feeding pump which are sequentially connected, wherein the coal slurry feeding pump is connected with the additive crushing unit, the additive crushing unit is used for crushing the structure of an additive, the water separation unit is used for separating water in the coal slurry with the structure of the additive crushed, the additive crushing unit is connected with the water separation unit, the water separation unit is provided with a water outlet and a coal outlet, the water outlet is connected with the water collection tank, and the coal outlet is connected with the gasification furnace; the concentration of the coal water slurry is improved, and the phenomenon that a large amount of water enters the gasification furnace to be evaporated to occupy the heat in the gasification furnace is avoided, so that the temperature in the gasification furnace is maintained by avoiding extra energy consumption, and the gasification cost of the coal water slurry is saved.)

1. A coal gasification system, characterized by: including slurrying and conveying unit, additive break unit (8), moisture separation unit (9), gasifier (11) and moisture collection tank (12), slurrying and conveying unit are including coal pulverizer (3), coal slurry jar (6) and coal slurry feed pump (7) that connect in order, coal slurry feed pump (7) with additive break unit (8) and connect, additive break unit (8) are used for destroying the structure of additive, moisture separation unit (9) are arranged in will breaking the moisture separation in the coal slurry of additive structure, additive break unit (8) with moisture separation unit (9) are connected, moisture separation unit (9) are provided with delivery port and coal outlet, the delivery port with moisture collection tank (12) are connected, the coal outlet with gasifier (11) are connected.

2. The coal gasification system of claim 1, wherein: the additive removing unit (8) comprises an inner cylinder (81) and an outer cylinder (82) which are coaxially arranged, the outer cylinder (82) is provided with a steam inlet (83) and a condensate outlet (84), and the inner cylinder (81) is provided with a coal water slurry inlet (85) and a coal water slurry outlet (86).

3. The coal gasification system of claim 2, wherein: the gasification furnace is characterized by further comprising a heat recovery unit, the heat recovery unit is connected with the slag discharge port of the gasification furnace (11), the heat recovery unit utilizes high-temperature ash discharged from the gasification furnace (11) to exchange heat to generate steam, and the steam is introduced into the steam inlet (83).

4. The coal gasification system according to claim 3, characterized in that: the heat recovery unit comprises a chilling chamber (16) and an inlet pipe (17), wherein a slag discharging pipe (15) is arranged at the lower end of the gasification furnace (11), the slag discharging pipe (15) extends into the chilling chamber (16), the inlet pipe (17) extends into the chilling chamber (16) from the outside, a first pressure release valve (18) is arranged in the chilling chamber (16), and the first pressure release valve (18) is connected with a steam inlet (83).

5. The coal gasification system of claim 4, wherein: the heat recovery unit further comprises a variable pressure slag lock (19) and a variable pressure cache tank (20), the chilling chamber (16), the variable pressure slag lock (19) and the variable pressure cache tank (20) are sequentially connected, a first switch valve (21) is arranged between the chilling chamber (16) and the variable pressure slag lock (19), a second switch valve (22) is arranged between the variable pressure slag lock (19) and the variable pressure cache tank (20), a first charging opening (23) and a second relief valve (24) are arranged on the variable pressure slag lock (19), the variable pressure cache tank (20) is provided with a second charging opening (25) and a third relief valve (26), and the second relief valve (24) and the third relief valve (26) are connected with the steam inlet (83).

6. The coal gasification system according to claim 3, characterized in that: further comprising a steam boiler (27), the steam boiler (27) being arranged between the heat recovery unit and the steam inlet (83).

7. The coal gasification system of claim 4, wherein: also included is a smoke filtering and flare disposing device (28), the smoke filtering and flare disposing device (28) being disposed between the pressure relief valve one (18) and the steam inlet (83).

8. The coal gasification system of claim 1, wherein: the water-based solar water heater is characterized by further comprising a pressure reducing unit (13) and a buffer tank (14), wherein the water collecting tank (12) is connected with the buffer tank (14) through the pressure reducing unit (13).

9. A method for concentrating coal water slurry is characterized in that: the method comprises the following steps:

A. the coal mill (3) mixes and grinds coal, water and additives to form coal water slurry, and the coal water slurry is stored in a coal slurry tank (6);

B. pumping the coal water slurry from the coal slurry tank (6) to the additive breaking unit (8) through the coal slurry feeding pump (7), and breaking the structure of additive molecules by the additive breaking unit (8) so that the stability of the coal water slurry is poor;

C. the water content in the water-coal-slurry with poor stability is separated by a water content separation unit (9) and the water-coal-slurry is concentrated;

D. the water enters a water collecting tank (12) through a water outlet to be recovered, and the coal water slurry with part of water removed enters a gasification furnace (11) to be gasified.

10. The coal-water slurry concentration method according to claim 9, characterized in that:

the step D is followed by the following steps:

E. high-temperature coal slag in the gasification furnace (11) enters a chilling chamber (16) through a slag discharge pipe (15), meanwhile, a water inlet pipe (17) introduces cooling water into the chilling chamber (16), and a first pressure release valve (18) is opened to introduce steam into a steam boiler (27);

F. coal slag enters a pressure-variable slag lock (19) through a first switch valve (21), a second pressure release valve (24) is opened, and steam is introduced into a steam boiler (27); coal slag enters a pressure-changing cache tank (20) through a second switch valve (22), a third relief valve (26) is opened, and steam is introduced into a steam boiler (27);

G. the additive breaking unit (8) comprises an inner cylinder (81) and an outer cylinder (82) which are coaxially arranged, the outer cylinder (82) is provided with a steam inlet (83) and a condensate outlet (84), and the inner cylinder (81) is provided with a coal water slurry inlet (85) and a coal water slurry outlet (86); the steam boiler (27) works to generate high-temperature steam, and the high-temperature steam enters a cavity between the inner cylinder (81) and the outer cylinder (82) through the steam inlet (83).

Technical Field

The invention belongs to the technical field of coal gasification, and particularly relates to a coal gasification system and a coal water slurry concentration method.

Background

At present, the coal water slurry is mainly applied to the coal water slurry gasification technology, is formed by mixing coal powder with certain granularity, water and an additive according to a certain proportion, has good performances such as stability and fluidity, is safe to store, convenient to transport and measure and can be transported in a long distance.

Because the coal water slurry is required to have good stability and fluidity in the process of storage and transportation, the addition of additives is needed. The use of the additive greatly limits the increase of the coal slurry concentration while ensuring the stability and the fluidity. The concentration of the existing industrialized coal water slurry is basically about 60 percent (wt), a large amount of water in the coal water slurry needs to be evaporated in the gasification process, and the water evaporation can absorb the heat in the gasification furnace, so that more coal powder and oxygen need to be consumed for combustion to maintain the coal gasification reaction temperature in the gasification furnace, and the coal water slurry gasification technology has the defects of generally low overall efficiency, higher specific coal consumption and oxygen consumption and lower effective gas content.

Therefore, how to improve the concentration of the coal water slurry entering the gasification furnace and improve the gasification efficiency of the coal water slurry becomes a major problem to be solved urgently in the development of the coal water slurry gasification technology.

Disclosure of Invention

The invention aims to provide a coal gasification system, which can improve the concentration of coal water slurry entering a gasification furnace and improve the gasification efficiency of the coal water slurry.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides a coal gasification system, breaks unit, moisture separation unit, gasifier and moisture collection tank including slurrying and conveying unit, additive, slurrying and conveying unit are including the coal pulverizer, coal slurry jar and the coal slurry charge pump that connect in order, the coal slurry charge pump with the unit connection is broken to the additive, the additive breaks the structure that the unit is used for destroying the additive, moisture separation unit is arranged in the water coal slurry that has broken the additive structure moisture separation, the additive break the unit with moisture separation unit connects, moisture separation unit is provided with delivery port and coal outlet, the delivery port with the moisture collection tank is connected, the coal outlet with the gasifier is connected.

Optionally, the additive breaking unit comprises an inner cylinder and an outer cylinder which are coaxially arranged, the outer cylinder is provided with a steam inlet and a condensate outlet, and the inner cylinder is provided with a coal water slurry inlet and a coal water slurry outlet.

Optionally, the gasifier also comprises a heat recovery unit, the heat recovery unit is connected with the slag discharge port of the gasifier, the heat recovery unit utilizes the high-temperature ash discharged from the gasifier to exchange heat to generate steam, and the steam is introduced into the steam inlet.

Optionally, the heat recovery unit includes chilling chamber and inlet tube, the lower extreme of gasifier is provided with the scum pipe, the scum pipe extend to in the chilling chamber, the inlet tube extends to from the outside in the chilling chamber, the chilling chamber is provided with relief valve one, relief valve one with steam inlet connects.

Optionally, the heat recovery unit further comprises a variable pressure slag lock and a variable pressure cache tank, the chilling chamber is connected with the variable pressure cache tank in sequence, a first switch valve is arranged between the chilling chamber and the variable pressure slag lock, a second switch valve is arranged between the variable pressure slag lock and the variable pressure cache tank, a first pressurizing opening and a second pressure relief valve are arranged on the variable pressure slag lock, a second pressurizing opening and a third pressure relief valve are arranged on the variable pressure cache tank, and the second pressure relief valve and the third pressure relief valve are connected with the steam inlet.

Optionally, the heat recovery system further comprises a steam boiler, wherein the steam boiler is arranged between the heat recovery unit and the steam inlet.

Optionally, the steam generator further comprises a smoke filtering and flare treating device, wherein the smoke filtering and flare treating device is arranged between the first pressure release valve and the steam inlet.

Optionally, the water-saving device further comprises a pressure reducing unit and a buffer tank, wherein the moisture collecting tank is connected with the buffer tank through the pressure reducing unit.

The invention aims to provide a method for concentrating coal water slurry, which can improve the concentration of the coal water slurry entering a gasification furnace and improve the gasification efficiency of the coal water slurry.

In order to achieve the purpose, the invention adopts the following technical scheme: a coal water slurry concentration method comprises the following steps:

A. mixing and grinding coal, water and an additive by a coal mill to form coal water slurry, and storing the coal water slurry into a coal slurry tank;

B. pumping the coal water slurry from the coal slurry tank to the additive breaking unit by the coal slurry feeding pump, and breaking the structure of additive molecules by the additive breaking unit to deteriorate the stability of the coal water slurry;

C. separating the water in the coal water slurry with the poor stability by a water separation unit, and concentrating the coal water slurry;

D. the water enters a water collecting tank through a water outlet to be recovered, and the coal water slurry with part of water removed enters a gasification furnace to be subjected to gasification reaction.

E. High-temperature coal slag in the gasifier enters a chilling chamber through a slag discharging pipe, meanwhile, cooling water is introduced into the chilling chamber through a water inlet pipe, and a first pressure release valve is opened to introduce steam into a steam boiler;

F. coal slag enters the pressure-variable slag lock through the first switch valve, and steam is introduced into the steam boiler by opening the second pressure release valve; the coal slag enters a variable pressure cache tank through a second switch valve, and a third relief valve is opened to introduce steam into a steam boiler;

G. the additive breaking unit comprises an inner cylinder and an outer cylinder which are coaxially arranged, the outer cylinder is provided with a steam inlet and a condensate outlet, and the inner cylinder is provided with a coal water slurry inlet and a coal water slurry outlet; the steam boiler works to generate high-temperature steam, and the high-temperature steam enters the clamping cavity between the inner cylinder and the outer cylinder through the steam inlet.

Compared with the prior art, the additive breaking unit and the moisture separating unit are arranged between the pulping and conveying unit and the gasification furnace, the additive breaking unit is adopted to break the structure of additive molecules, so that the stability of the coal water slurry is poor, coal particles are settled, then the water is separated from the coal particles through the moisture separating unit, the concentration of the coal water slurry is improved, the high-concentration coal water slurry enters the gasification furnace for gasification reaction, the water is separated, a large amount of water is prevented from entering the gasification furnace to be evaporated, the heat in the gasification furnace is occupied, the additional energy consumption is avoided, the temperature in the gasification furnace is maintained, and the gasification cost of the coal water slurry is saved.

Drawings

FIG. 1 is a schematic view of an embodiment of a coal gasification system provided in accordance with the present invention;

fig. 2 is a schematic view of the connection of the additive removal unit and the heat recovery unit.

Reference numerals:

1. a coal bunker; 2. a coal weighing feeder; 3. a coal mill; 4. a coal slurry discharge chute; 5. a coal slurry discharge tank pump; 6. a coal slurry tank; 7. a coal slurry feed pump; 8. an additive breaking unit; 81. an inner barrel; 82. an outer cylinder; 83. a steam inlet; 84. a condensate outlet; 85. a coal water slurry inlet; 86. a coal water slurry outlet; 87. a stirring unit; 9. a moisture separation unit; 10. a gasification burner; 11. a gasification furnace; 12. a moisture collection tank; 13. a pressure reducing unit; 14. a buffer tank; 15. a slag discharge pipe; 16. a quench chamber; 17. a water inlet pipe; 18. a first pressure relief valve; 19. transforming the pressure of the slag lock; 20. a pressure-variable buffer tank; 21. a first switch valve; 22. a second switch valve; 23. a first pressurizing opening; 24. a second pressure release valve; 25. a second pressurizing port; 26. a third pressure relief valve; 27. a steam boiler; 28. a smoke filtering and torch treatment device; 29. a flow meter.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, the present invention will be further described in detail with reference to the accompanying drawings and examples. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. The specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the invention, are within the scope of the invention.

As shown in fig. 1, the coal gasification system provided by the present invention includes a slurry preparation and delivery unit, an additive breaking unit 8, a moisture separation unit 9, a gasification burner 10, a gasification furnace 11 and a moisture collection tank 12, wherein the slurry preparation and delivery unit includes a coal mill 3, a coal slurry tank 6 and a coal slurry feed pump 7, the coal mill 3 is used for mixing and grinding coal, water and additives to form coal slurry, the coal slurry tank 6 is used for storing the coal slurry, the coal slurry feed pump 7 is used for delivering the coal slurry in the coal slurry tank 6 to the additive breaking unit 8, the additive breaking unit 8 is used for destroying the structure of the additives, the moisture separation unit 9 is used for separating moisture in the coal slurry with the broken structure of the additives, the moisture separation unit 9 is provided with a water outlet and a coal outlet, the water outlet is connected with the moisture collection tank 12, and the coal outlet is connected with the gasification furnace 11 through the gasification burner 10.

Compared with the prior art, the additive breaking unit 8 and the moisture separation unit 9 are arranged between the pulping and conveying unit and the gasification furnace 11, the additive breaking unit 8 is adopted to break the structure of additive molecules, so that the stability of the coal water slurry is poor, coal particles are settled, then the moisture is separated from the coal particles through the moisture separation unit 9, the concentration of the coal water slurry is improved, the high-concentration coal water slurry enters the gasification furnace 11 for gasification reaction, the moisture is separated, a large amount of water is prevented from entering the gasification furnace 11 to be evaporated, the heat in the gasification furnace 11 is occupied, the additional energy consumption is avoided, the temperature in the gasification furnace 11 is maintained, and the gasification cost of the coal water slurry is saved.

The additive breaking unit 8 can break the molecular structure of the additive by adopting methods of high temperature, changing the pH value of the coal water slurry or adding a polymerization initiator and the like, so that the additive is separated from the surface of coal particles and is dissolved in water; the moisture separation unit 9 may be in the form of a flash tank, reverse osmosis, hydrocyclone, etc., preferably a hydrocyclone. The overflow port at the upper part of the hydrocyclone is a water outlet, and the lower port of the hydrocyclone is a coal outlet.

Further, as shown in fig. 2, the additive removing unit 8 is preferably a heating device, because the heating device can further evaporate water, the additive removing unit 8 includes an inner cylinder 81 and an outer cylinder 82 which are coaxially arranged, the outer cylinder 82 is provided with a steam inlet 83 and a condensate outlet 84, and the inner cylinder 81 is provided with a coal water slurry inlet 85 and a coal water slurry outlet 86. The coal water slurry in the inner cylinder 81 is heated through the outer cylinder 82, the structure of the additive molecules is damaged due to the temperature rise, the stability of coal particles is poor, the coal water slurry is further easy to settle, and the coal water slurry is convenient to enter the moisture separation unit 9 for separation, so that the separation rate of water and coal particles in the coal water slurry is further improved, and the concentration of the coal water slurry is improved.

As a preferred embodiment, sodium polystyrene sulfonate or sodium lignin sulfonate is used as the additive, and the temperature in the inner cylinder 81 is controlled at 250 ℃ to 350 ℃, so that the structure of the sodium polystyrene sulfonate or the sodium lignin sulfonate can be completely destroyed.

In some embodiments, as shown in FIG. 2, a stirring unit 87 is further disposed within the inner cylinder 81. After the coal water slurry is heated by the additive breaking unit 8, coal particles in the coal water slurry are easy to settle, and if the coal water slurry is not stirred at the moment, the coal particles are not easy to settle and enter the moisture separation unit 9 from the coal water slurry outlet 86.

In some embodiments, as shown in fig. 2, a heat recovery unit is further included, and the heat recovery unit is used for recovering waste heat of high-temperature coal slag in the gasification furnace 11, and comprises a chilling chamber 16, a pressure swing slag lock 19 and a pressure swing cache tank 20.

The concentrated coal water slurry enters a gasification furnace 11 to generate a coal gasification reaction, the operation pressure of the gasification furnace 11 is controlled to be 3.0-4MPa, the temperature is controlled to be 750-;

high-temperature coal slag in the gasification furnace 11 enters a chilling chamber 16 through a slag discharge pipe 15, meanwhile, cooling water is introduced into the chilling chamber 16 through a water inlet pipe 17, the cooling water and the high-temperature coal slag perform direct heat exchange, at the moment, the pressure in the chilling chamber 16 and the pressure in the gasification furnace 11 are kept unchanged by controlling a first pressure release valve 18, and meanwhile, high-temperature high-pressure saturated steam is discharged through the first pressure release valve 18; the system also comprises a smoke dust filtering and torch processing device 28, wherein the smoke dust filtering and torch processing device 28 is arranged between the first pressure release valve 18 and the steam inlet 83, and certain smoke dust and crude coal gas are possibly mixed in high-temperature and high-pressure saturated steam discharged from the chilling chamber 16, so that the smoke dust is further filtered and the crude coal gas is combusted through the smoke dust filtering and torch processing device 28, and then the steam is introduced into the boiler 27;

the chilling chamber 16 is connected with the variable pressure slag lock 19, the variable pressure slag lock 19 is provided with a first pressurizing opening 23, high-pressure low-temperature water is used for pressurizing, the variable pressure slag lock 19 is subjected to pressurizing operation, the pressure of the variable pressure slag lock is slightly lower than that of the chilling chamber 16, a first switch valve 21 between the chilling chamber 16 and the variable pressure slag lock 19 is periodically opened, a mixture of water and coal slag is discharged to the variable pressure slag lock 19, after the variable pressure slag lock 19 enters a certain amount of mixture of water and coal slag, a second switch valve 21 is closed, a second pressure release valve 24 is opened to perform pressure reduction operation on the variable pressure slag lock 19, the pressure is reduced to 1-1.5MPa, and medium-temperature medium-pressure saturated steam flashed in the pressure reduction process is discharged through the second pressure release valve 24 and;

the variable pressure slag lock 19 is connected with the variable pressure cache tank 20, the variable pressure cache tank 20 is provided with a second pressurizing opening 25, high-pressure low-temperature water is used for pressurizing, the pressure of the variable pressure cache tank 20 is slightly lower than the pressure of the variable pressure slag lock 19, a second switch valve 22 between the variable pressure cache tank and the variable pressure slag lock is opened, a mixture of water and coal slag in the variable pressure slag lock 19 is discharged into the variable pressure cache tank 20, after a certain amount of mixture of water and coal slag enters the variable pressure cache tank 20, the second switch valve 22 is closed, a third pressure release valve 26 is opened to carry out pressure reduction operation on the variable pressure cache tank 20, the pressure is reduced to 0.1-0.3MPa, low-pressure saturated steam is flashed out and is discharged through the third pressure;

in order to fully achieve gas-liquid balance, the transformation slag lock 19 and the transformation cache tank 20 adopt the same internal structure as the chilling chamber 16, so that enough flash evaporation space is ensured on the transformation slag lock 19 and the transformation cache tank 20.

The steam boiler 27 recycles the steam discharged from the chilling chamber 16, the variable pressure slag lock 19 and the variable pressure cache tank 20, if the temperature reaches a set value, the steam boiler 27 directly uses the recycled steam for heating the water-coal-slurry in the inner cylinder 81 without heating, if the temperature does not reach the set value, the steam boiler 27 secondarily heats the recycled steam for heating the water-coal-slurry in the inner cylinder 81, the condensate outlet 84 can also be connected with the steam boiler 27, and through the arrangement of the recycled steam, the waste heat of the high-temperature coal slag is effectively utilized to concentrate the water-coal-slurry, so that the energy consumption is greatly saved.

In some embodiments, as shown in fig. 1, the system further comprises a pressure reduction unit 13 and a buffer tank 14, and the moisture collection tank 12 is connected with the buffer tank 14 through the pressure reduction unit 13. The pressure reducing unit 13 may be a pressure reducing valve, the buffer tank 14 may be a flash tank, the separated moisture first enters the collecting tank 12, then enters the flash tank after being reduced in pressure by the pressure reducing valve, the steam of the flash is discharged, and the residual moisture in the flash tank is treated.

In some embodiments, as shown in fig. 1, a coal bunker 1 and a coal weigh feeder 2 are also included, the coal weigh feeder 2 being used to transport coal from the coal bunker 1 to a coal pulverizer 3. The coal bunker 1 is a raw coal storage device, and the coal weighing feeder 2 is a conveying device.

In some embodiments, as shown in fig. 1, the coal slurry discharging tank 4 and the coal slurry discharging tank pump 5 are further included, the coal slurry discharging tank 4 is disposed at a discharging port of the coal pulverizer 3, and the coal slurry discharging tank pump 5 is used for conveying the coal water slurry from the coal slurry discharging tank 4 to the coal slurry tank 6.

A coal water slurry concentration method comprises the following steps:

A. the coal mill 3 mixes and grinds coal, water and additives to form coal water slurry, and the coal water slurry is stored in a coal slurry tank 6;

B. pumping the coal water slurry from the coal slurry tank 6 to the additive breaking unit 8 by the coal slurry feeding pump 7, and adopting the additive breaking unit 8 to break the structure of the additive molecules, so that the stability of the coal water slurry is deteriorated;

C. the water content in the water-coal-slurry with poor stability is separated by a water content separation unit 9, and the water-coal-slurry is concentrated;

D. the water enters a water collecting tank 12 through a water outlet to be recovered, and the coal water slurry with part of water removed enters a gasification furnace 11 to carry out gasification reaction;

E. high-temperature coal slag in the gasification furnace 11 enters a chilling chamber 16 through a slag discharge pipe 15, meanwhile, cooling water is introduced into the chilling chamber 16 through a water inlet pipe 17, and a first pressure release valve 18 is opened to introduce steam into a steam boiler 27;

F. coal slag enters the variable pressure slag lock 19 through the first switch valve 21, and steam is introduced into the steam boiler 27 by opening the second pressure release valve 24; the coal slag enters a pressure-changing cache tank 20 through a second switch valve 22, and steam is introduced into a steam boiler 27 by opening a third relief valve 26;

G. the additive breaking unit 8 comprises an inner cylinder 81 and an outer cylinder 82 which are coaxially arranged, the outer cylinder 82 is provided with a steam inlet 83 and a condensate outlet 84, and the inner cylinder 81 is provided with a coal water slurry inlet 85 and a coal water slurry outlet 86; the steam boiler 27 is operated to generate high temperature steam, and the high temperature steam enters the cavity between the inner drum 81 and the outer drum 82 through the steam inlet 83.

One embodiment of the present invention is as follows:

after a gate valve at the bottom of the coal bunker 1 is opened, pulverized coal continuously enters the coal weighing feeder 2 from a discharge port at the bottom, and a path of low-pressure nitrogen is introduced into the lower half part of the coal bunker 1 so as to prevent coal in the coal bunker 1 from spontaneous combustion;

the mass flow of the coal powder entering a coal mill 3 is determined by setting the belt speed of a coal weighing feeder 2, meanwhile, water and additive sodium polystyrene sulfonate are metered by a flowmeter 29 and flow into the coal mill 3, after being mixed and ground by the coal mill 3, the coal water slurry with the average particle size of about 100 microns flows into a coal slurry discharge chute 4, the concentration of the coal water slurry is 60 percent (wt), and the concentration of the sodium polystyrene sulfonate is 1 percent (wt);

the coal slurry discharging tank 4 is provided with a stirrer and is used for preventing coal particles in the coal water slurry from settling; the discharge hole at the bottom of the coal slurry discharge tank 4 is required to be at a certain height from the ground, and in order to ensure the inlet pressure of the coal slurry discharge tank pump 5, the coal slurry discharge tank pump 5 conveys the coal water slurry into a coal slurry tank 6;

the discharge hole at the bottom of the coal slurry tank 6 also needs to be at a certain height from the ground, and in order to ensure the inlet pressure of the coal slurry feeding pump 7, the coal slurry feeding pump 7 conveys the coal water slurry to the inner cylinder 81;

hot steam is introduced into a space between the outer cylinder 82 and the inner cylinder 81 through the steam inlet 83, the coal water slurry in the inner cylinder 81 is heated to 350 ℃ from the normal temperature, the coal slurry feeding pump 7 provides certain pressure for the inner cylinder 81, the heated coal water slurry is pushed to the moisture separation unit 9 by the pressure, the concentration of the separated and concentrated coal water slurry is 65-80% (wt), the coal water slurry is fully mixed with oxygen through the gasification burner 10, and the atomized coal particles enter the gasification furnace for reaction.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.