CN218058906U - Water-cooled wall pressurized fluidized bed gasification furnace - Google Patents

Abstract

A water-cooled wall pressurized fluidized bed gasifier. The prior art is in a shell lining refractory brick form, the ash residue in a furnace corrodes the refractory bricks to cause the refractory bricks to crack, damage and fall off, and the local overtemperature of a gasification furnace shell causes huge potential safety hazards. The utility model discloses the constitution includes: the method comprises the following steps: pressure-bearing casing (1), synthesis gas export (9) are installed at pressure-bearing casing top, ash outlet (5) have in its bottom, return material mouth (6) are installed in pressure-bearing casing left side, feed inlet (7) are installed respectively on its right side, feed supplement mouth (8), pressure-bearing casing internally mounted has membrane wall (2), assemble collection box (10) are installed at membrane wall top, distribution collection box (11) are installed to its bottom, membrane wall tube panel (12) are formed by heat exchange tube and fin welding, and install refractory lining (13) to the fire face side promptly at membrane wall tube panel inboard, membrane wall upper portion and lower part are circular cross section. The utility model is used for water-cooling wall pressurized fluidized bed gasifier.

Description

Water-cooled wall pressurized fluidized bed gasification furnace

The technical field is as follows:

the utility model relates to a gasification technical field, concretely relates to water-cooling wall pressurized fluidized bed gasifier.

Background art:

the fluidized bed gasification furnace is a place where gasification reaction is carried out by blowing up small-particle gasification raw materials of 0-10mm to a fluidized state with the apparent characteristics of fluid by using a gasifying agent; in a reaction hearth, the gasified raw materials are vigorously stirred and back-mixed to fully contact with a gasifying agent, so that chemical reaction and heat transfer are carried out; the fluidized bed gasification furnace in the prior art is in a shell lining refractory brick form, ash and slag in the furnace can corrode refractory bricks, gas-solid media in coal gasification can penetrate into gaps of the refractory bricks to cause cracking, damage and even large-piece falling of the refractory bricks, and the local overtemperature of the gasification furnace shell causes huge potential safety hazards. The gas flow density in the normal pressure fluidized bed gasification furnace is low, the gas flow speed is high, and more solid particles are brought out of the synthetic gas discharged from the furnace; the gasification reaction under normal pressure occupies a large gasification space, and the gasification intensity by volume is much smaller than that under the pressurization working condition; the pressure grade of the synthesis gas generated by normal-pressure gasification is low, which is not beneficial to the subsequent processes of direct connection, such as transformation, purification and the like of the synthesis gas;

the utility model has the following contents:

the utility model aims at providing a water-cooling wall pressurized fluidized bed gasifier, this structure and method have overcome the interior lime-ash of stove in the operation process and have corroded, ftracture, damage scheduling problem to resistant firebrick, adopt the intraductal saturated water that is full of water-cooling wall to maintain the water-cooling wall constancy of temperature, have effectively avoided the too high temperature trade difficult point of casing operation, guarantee the long period safe and reliable's of equipment continuous operation.

The above purpose is realized by the following technical scheme:

a water-cooled wall pressurized fluidized bed gasifier, comprising: the composite material membrane wall comprises a pressure-bearing shell, wherein a synthetic gas outlet is arranged at the top of the pressure-bearing shell, an ash residue outlet is arranged at the bottom of the pressure-bearing shell, a return port is arranged at the left side of the pressure-bearing shell, a feed inlet and a feed supplement port are respectively arranged at the right side of the pressure-bearing shell, a membrane wall is arranged in the pressure-bearing shell, a gathering box is arranged at the top of the membrane wall, a distribution box is arranged at the bottom of the membrane wall, a membrane wall tube panel is formed by welding heat exchange tubes and fins, a fire-resistant liner is arranged on the inner side of the membrane wall tube panel, namely the fire facing side, the upper part and the lower part of the membrane wall are both circular cross sections, and the ratio of the diameter of the upper part cross section to the diameter of the lower part of the membrane wall panel is 1~2. The middle of the membrane water-cooled wall is in conical transition, and the conical included angle is 20-60 degrees.

The water-cooled wall pressurized fluidized bed gasifier is characterized in that the upper part of the membrane water-cooled wall is narrowed to be in sealing fit with the synthesis gas outlet and axially and relatively slide, the lower part of the membrane water-cooled wall is in sealing fit with the gas distributor, the material returning port is obliquely and downwards arranged, the included angle between the axis of the material returning port and the axis of the gasifier is 30-70 degrees, the included angle between the axis of the material returning port and the axis of the gasifier is obliquely and downwards arranged to be 30-70 degrees, the number of the material feeding ports is one group, and a group of anti-vibration devices are installed between the pressure-bearing shell and the membrane water-cooled wall.

Has the beneficial effects that:

1. the utility model relates to a water-cooling wall pressurized fluidized bed gasifier, this structure and method have solved the problem that the ordinary pressure resistant firebrick fluidized bed gasifier gasification intensity among the prior art is lower, resistant firebrick is perishable and is damaged, and the built-in water-cooling wall of fluidized bed gasifier can maintain furnace temperature stable simultaneously, and the operation of casing overtemperature superpressure causes the problem of damage harm goods and materials and personnel's safety when avoiding the gasifier trouble.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier is the pressurization operation, and gasification pressure's improvement helps making gasification intensity promote, reduces the energy consumption loss, optimizes follow-up technology configuration, and the gasifier is inside to set up water-cooling wall cavity structures, and the water-cooling wall can guarantee the interior constancy of temperature of stove, avoids in the past fluidized bed gasifier resistant firebrick inefficacy to cause local overtemperature and the condition of being forced to shut down, is favorable to fluidized bed equipment safety and stability operation.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier, gasifier pressurized operation are favorable to increasing reaction gas's concentration, reduce air velocity under the same flow, increase the contact time of gasifying agent and gasification raw materials, improve the synthetic gas productivity, reduce former material ash.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier can reduce the size of gasifier under equal gasification demand, practices thrift disposable investment.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier, if need gasification raw materials production methane, pressure improves and is favorable to the formation of methane, and the calorific value that generates the synthetic gas improves.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier, it is high to compare prior art uses the thermal-insulated gasifier security of resistant firebrick, it is mutual drag hook self-locking structure to adopt between the thermal-insulated fluidized bed gasifier brick of resistant firebrick and the brick, if the local damage causes the big piece condition of droing easily in the operation process, and can have more or less clearance when building bricks by laying bricks or stones, above-mentioned factor all can lead to the gasifier casing in the operation process overtemperature, gasification reaction resultant is flammable explosive gas, resistant firebrick inefficacy can bring huge potential safety hazard, this equipment gasification chamber adopts the water-cooling wall to enclose, the intraductal saturated water that is full of water-cooling wall maintains the water-cooling wall temperature invariable, casing operating temperature is low, thereby can reduce casing thickness and reduce equipment metal weight; meanwhile, the water-cooled wall structure effectively avoids the industrial difficulty of overtemperature of the shell operation and ensures the long-period safe and reliable continuous operation of the equipment.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier, water-cooling wall constancy of temperature helps keeping the intracavity temperature of gasification even, and the gasification reaction is stable.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier, water-cooling wall temperature can the rigidity, and the temperature setting is higher than synthetic gas dew point temperature and can avoid water-cooling wall and refractory material to receive acid gas corrosion.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier sets up the feed supplement mouth in the dilute phase district, can import nimble feeding more, the regulation of the gasification temperature and the gasification intensity of being convenient for.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier arranges a plurality of groups anti vibration guider in the inert gas intracavity, and the relative casing distance of water-cooling wall is invariable and difficult emergence is twistd reverse, guarantees that the water-cooling wall freely upwards expands in order.

The utility model discloses a water-cooling wall pressurized fluidized bed gasifier arranges temperature measurement station and pressure measurement station at gasification chamber and inert gas intermediate layer, controls the operating parameter of each cavity through adjusting working medium input/output volume in inert gas and the water-cooling wall, keeps equipment even running.

Description of the drawings:

fig. 1 is a schematic structural diagram of the present invention.

Wherein: 1. the device comprises a pressure-bearing shell, 2, a membrane wall, 3, a vibration-proof device, 4, a gas distributor, 5, an ash residue outlet, 6, a return material port, 7, a feed port, 8, a feed supplement port, 9, a synthesis gas outlet, 10, a gathering header, 11, a distribution header, 12, a membrane wall tube panel, 13 and a refractory lining;

the area A is: dilute phase zone, zone B: dense phase zone, zone C: air chamber, zone D: an inert gas ring cavity.

The specific implementation mode is as follows:

example 1:

a water-cooled wall pressurized fluidized bed gasifier, comprising: the composite material heat exchanger comprises a pressure-bearing shell 1, wherein a synthetic gas outlet 9 is installed at the top of the pressure-bearing shell, an ash residue outlet 5 is arranged at the bottom of the pressure-bearing shell, a return port 6 is installed at the left side of the pressure-bearing shell, a feed inlet 7 and a feed supplement port 8 are respectively installed at the right side of the pressure-bearing shell, a membrane water wall 2 is installed in the pressure-bearing shell, a gathering box 10 is installed at the top of the membrane water wall, a distribution box 11 is installed at the bottom of the membrane water wall, a membrane wall tube panel 12 is formed by welding heat exchange tubes and fins, a refractory lining 13 is installed on the inner side of the membrane wall tube panel, namely the fire facing side, the upper part and the lower part of the membrane water wall are both circular sections, the ratio of the diameter of the upper section to the diameter of the lower section is 1~2, the middle of the membrane water wall is in conical transition, and the conical included angle is 20-60 degrees;

the membrane water-cooled wall is arranged in the pressure-bearing shell, the upper part of the membrane water-cooled wall is narrowed to be in sealing fit with the synthesis gas outlet and axially and relatively slide, the lower part of the membrane water-cooled wall is in sealing fit with the gas distributor 4, the material returning port is obliquely and downwards arranged, the included angle between the axis of the material returning port and the axis of the gasification furnace is 30-70 degrees, the included angle between the axis of the material returning port and the axis of the gasification furnace is obliquely and downwards arranged at 30-70 degrees, the number of the material feeding ports is one group, and a group of anti-vibration devices 3 are arranged between the pressure-bearing shell and the membrane water-cooled wall;

saturated water is introduced into each heat exchange tube from a distribution header at the bottom of the membrane water wall, the saturated water absorbs heat in the heat exchange tubes and flows upwards to enter a gathering header and then is led out of the gasification furnace, the temperature of the membrane water wall is kept constant, the temperature of a pressure-bearing shell is ensured to be constant, refractory materials are laid on the inner wall of the membrane water wall, and the heat of the membrane water wall taken away from a gasification reaction zone is reduced;

because the ash carrying amount of the synthesis gas of the fluidized bed gasification furnace is large, the synthesis gas separates the incompletely reacted coal ash or ash through a separator, the separated material is sent to the lower part of the gasification furnace through a material returning opening, and the material returning opening is obliquely and downwards arranged, so that the included angle between the axis of the material returning opening and the axis of the gasification furnace is 30-70 degrees;

the material enters a membrane type water-cooled wall cavity through a feed inlet at the lower part of the gasification furnace for gasification reaction, the feed inlet is obliquely and downwards arranged, the included angle between the axis of the feed inlet and the axis of the gasification furnace is 30-70 degrees, a plurality of feed inlets can be arranged, the number of the feed inlets is 2~8, and the gasification material can be coal or a mixture of the coal and other carbon carriers;

the area below the gas distribution plate is a gas chamber, a gasification agent is introduced into the gas chamber and is blown into a gasification reaction area upwards through the gas distribution plate, the gas distribution plate is of a conical structure, the gasification agent is divided into a plurality of strands, each strand of gasification agent can be blown in from a central hole of the gas distribution plate and openings of the conical plate, the gas chamber is provided with a film-free water-cooled wall, and a firebrick is laid in a shell of the area to avoid the overtemperature of the shell;

the gasification pressure, namely the reaction pressure in the water-cooling wall annular cavity is 0.1 to 5Mpa;

the area enclosed between the gasification furnace shell and the membrane type water wall is an inert gas annular cavity, the inside of the inert gas annular cavity is filled with gases which are difficult to react, such as nitrogen, carbon dioxide and the like, the pressure in the annular cavity is slightly higher than that of the gasification reaction cavity, and the pressure difference is 10kPa to 80kPa;

the inert gas ring cavity is provided with a plurality of groups of anti-vibration devices along the axial direction, the anti-vibration devices enable the shell and the water wall to move freely and relatively in the axial direction, but can only move in a small gap in the radial direction, and the anti-vibration devices can avoid severe vibration or torsion of the water wall. The anti-vibration device can be provided with a plurality of groups, the axial distance is generally one group from 2m to 5m, each group comprises a plurality of components which are uniformly distributed in the circumferential direction, and 3~8 anti-vibration components are generally arranged on one section;

coal or a mixture of the coal and other carbon carriers is fluidized and gasified in a water-cooled wall cavity, the solid particle content in the cavity is large, the water-cooled wall is locally free of shape mutation points, and the shape transition positions are arc-shaped slow transition positions;

in order to ensure complete gasification and stable temperature of a gasification area, a feed supplement port can be arranged at the middle upper part of the gasification furnace, and the feed supplement port can supplement a carbon-containing raw material or a gasification agent, so that complete reaction of steam and carbon is ensured, the conversion rate of carbon is improved, and the temperature in the gasification cavity is favorably controlled;

the gasification cavity and the inert gas annular cavity are respectively provided with a differential pressure monitoring system and a temperature monitoring system, and the pressure and the temperature in the two areas are monitored at any time when the gasification furnace runs, so that the safety of the running environment of the water-cooled wall and the shell of the gasification furnace is ensured;

the gasification method of the water-cooled wall pressurized fluidized bed gasification furnace comprises the following steps:

firstly, ash-containing raw material particles separated from gasification raw materials, gasification agents and synthesis gas with the particle size of less than 10mm are sent to the bottom of a gasification cavity, raw material pyrolysis and gasification reaction are carried out in the gasification cavity, the reaction temperature is 700-1100 ℃, and the reaction pressure is 0.1-5MPa;

the gasification agent enters from the bottom through the gas distributor and gasifies the raw material by fluidizing the gasification raw material through the gasification raw material layer, the diameter of the raw material particles is continuously reduced along with the gasification reaction, the free settling velocity of the raw material particles is reduced, and when the free settling velocity is reduced to the air velocity, the ash-containing raw material particles leave the gasification furnace along with the synthesis gas and enter the separator;

the area surrounded by the membrane type water-cooled wall is a gasification cavity, the area with smaller diameter at the lower part is a dense-phase area, the area with larger diameter at the upper part is a dilute-phase area, the gasification raw material and the gasification agent are sent to the dense-phase area for reaction, and meanwhile, the dilute-phase area can be properly supplemented with materials to control the temperature of each part of the gasification cavity to be uniform;

saturated water is introduced from the bottom into the heat exchange tubes of the membrane water walls, the saturated water absorbs heat and moves upwards in the heat exchange tubes to become saturated steam, the saturated steam enters the gathering header and is led out of the gasification furnace, the medium in the heat exchange tubes of the membrane water walls absorbs heat to generate phase change, and the temperature of the membrane water walls is kept unchanged;

a plurality of temperature measuring points are arranged along the axial direction of the gasification cavity, the temperature field in the hearth is monitored to be uniform, and the temperature difference in the hearth is ensured not to be more than 20 ℃ in a mode of locally supplementing materials or adjusting the flow rate of saturated water in a water-cooled wall;

and respectively arranging a plurality of pressure measuring points in the gasification cavity and the inert gas ring cavity, monitoring the axial pressure drop in the hearth to be matched with the thickness of the bed layer, and controlling the strong pressure difference range of the gasification cavity and the inert gas to be within the range of 10kPa to 80kPa by adjusting the input and output of the inert gas.

The pressure-bearing shell adopted by the application comprises an end enclosure, a barrel, a transition cone section and the like, wherein the pressure-bearing shell is provided with a gasification material inlet, an ash residue outlet, a water-cooled wall working medium inlet/outlet, a protective gas inlet/outlet, a sewage discharge outlet, a material supplementing opening, necessary pipe orifices for pressure monitoring, temperature monitoring and the like;

the membrane type water-cooled wall is arranged in the pressure-bearing shell, one point of the membrane type water-cooled wall can be fixedly connected with the pressure-bearing shell, the rest matching interface parts are hermetically connected with the pressure-bearing shell, the tube panel is formed by welding or winding tube heat pipes, the area surrounded by the tube panel is a gasification reaction cavity, the upper part of the tube panel is a dilute phase area, the lower part of the tube panel is a dense phase area, the cross sections of the dilute phase area and the dense phase area are circular, the diameter ratio is 1~2, and the areas surrounded by the tube panel are in smooth transition towards the fire side;

slag nails or rivets are uniformly arranged on the fire side of the area surrounded by the tube panel so as to lay refractory materials, and the excessive reaction heat absorbed by the medium in the water-cooled wall can be reduced by laying the refractory materials;

leading out the water-cooled wall working medium from a gathering header and a distribution header into a gasification furnace, wherein 2 to 10 leading-in/leading-out pipes can be arranged, and the leading-in/leading-out pipes are in a zigzag shape, a zigzag shape or a spiral winding shape and can absorb the expansion difference between the membrane water-cooled wall and a shell;

and the gasification raw material enters the reaction cavity through the feed inlet, the material return port and the material supplement port, the feeding direction is inclined downwards, and the axial direction of the pipe opening and the axial line of the gasification furnace form an included angle of 30 to 70 degrees. A plurality of feeding ports and returning ports can be arranged at different positions, and the stability of a flow field and a temperature field can be controlled by adjusting the feeding proportion and the feeding amount of each inlet during gasification reaction;

the area enclosed by the membrane type water-cooled wall and the shell is an inert gas interlayer cavity, gas which does not participate in reaction is filled in the inert gas interlayer cavity, and the working pressure of the interlayer cavity is maintained to be slightly greater than that of the gasification cavity, so that the strength failure of the tube panel can be avoided, and the synthesis gas leakage can be prevented;

the gas distributor is of a conical funnel structure, the edge of the gas distributor is connected to the bottom of the membrane type water-cooled wall in a sealing mode, the area enclosed by the gas distributor and the shell is a gas chamber, and a gasifying agent is blown into the gasification reaction cavity from the side of the gas chamber to fluidize a gasification raw material and return materials and fully mix and react with the gasification raw material and the return materials;

and pressure measuring points and temperature measuring points are arranged in the gasification cavity and the interlayer cavity along the axial direction of the gasification furnace. The feeding proportion of the gasifying agent and the materials is adjusted according to temperature feedback, so that the temperature of the gasification cavity is uniform; adjusting the pressure of the inert gas according to pressure feedback, wherein the pressure difference between the gasification cavity and the interlayer cavity is 1 to 80kPa;

the water-cooled wall pressurized fluidized bed gasification furnace can be used for gasification reaction of small-particle gasification raw materials of 0-10mm, and the gasification pressure is high, so that the airflow density is high, the airflow speed is low, the gasification efficiency is high, and the reaction is complete; the gasification flow rate is low, so that the discharged synthetic gas carries less solid particles, the pressurized gasification reaction has higher gasification strength by volume than the conventional normal-pressure working condition, the subsequent conversion and purification processes of the directly connected synthetic gas are also facilitated, and the dangerous condition that the strength of the shell fails due to the fact that the conventional medium frequently passes through gaps of refractory bricks due to the fact that the shell is over-temperature is avoided by the lining water-cooled wall structure of the shell; meanwhile, if the temperature of the refractory brick-lined gasification furnace is too thick and the temperature of the shell is too low to reach the dew point temperature of the synthesis gas, the condensate of the synthesis gas can cause the corrosion of the gasification furnace shell; the utility model eliminates the firebricks of the hot wall gasification furnace, reduces the total weight of the device and reduces the annual maintenance fire-resistant cost; meanwhile, the water-cooled wall structure can effectively avoid the overtemperature condition of the shell, and the safety and the reliability of the long-period continuous operation of the device are improved.

Claims (2)

1. A water-cooled wall pressurized fluidized bed gasifier, comprising: pressure-bearing shell, characterized by: the composite membrane wall is characterized in that a synthesis gas outlet is installed at the top of the pressure-bearing shell, an ash residue outlet is formed in the bottom of the pressure-bearing shell, a return port is installed on the left side of the pressure-bearing shell, a feed inlet and a feed supplement port are respectively installed on the right side of the pressure-bearing shell, a membrane wall is installed inside the pressure-bearing shell, a gathering box is installed at the top of the membrane wall, a distribution box is installed at the bottom of the membrane wall, a membrane wall tube panel is formed by welding heat exchange tubes and fins, a fire-resistant lining is installed on the inner side of the membrane wall tube panel, namely the fire facing side, the upper portion and the lower portion of the membrane wall are both provided with circular cross sections, the ratio of the diameter of the upper portion cross section to the diameter of the lower portion of the membrane wall is 1~2, the middle of the membrane wall is in conical transition, and a conical included angle is 20-60 degrees.

2. The water-cooled wall pressurized fluidized bed gasifier of claim 1, wherein: the upper portion of the membrane water-cooling wall is narrowed to be in sealing fit with the synthesis gas outlet and axially and relatively slide, the lower portion of the membrane water-cooling wall is in sealing fit with the gas distributor, the material returning port is obliquely and downwards arranged, the included angle between the axis of the material returning port and the axis of the gasification furnace is 30-70 degrees, the included angle between the axis of the material returning port and the axis of the gasification furnace is obliquely and downwards arranged to be 30-70 degrees, the number of the material feeding ports is one group, and a group of anti-vibration devices are installed between the pressure-bearing shell and the membrane water-cooling wall.

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