CN214612324U - Sleeve type double oxidation layer fixed bed gasification furnace - Google Patents

Abstract

The utility model discloses a sleeve type double oxidation layer fixed bed gasification furnace. The gasification furnace comprises: the device comprises a feeding device, a reaction zone furnace body, a furnace top gasifying agent air inlet, a middle section gasifying agent air inlet, a furnace bottom gasifying agent air inlet, a coal gas outlet, a gasifying agent distribution regulator and a slag discharging device. Wherein the upper section in the furnace body is provided with a material distribution device, the middle section is provided with a sleeve, the bottom is provided with a fire grate, an annular cavity is formed between the sleeve and the furnace wall, the upper part of the sleeve is of a structure with a wide upper part and a narrow lower part, and the upper end of the sleeve is abutted against the furnace wall; the furnace bottom gasification agent air inlet is communicated with the lower part of the furnace grate, the coal gas outlet is arranged in the middle of the furnace wall and is positioned in the area where the annular cavity is positioned, and the gasification agent distribution regulator can be arranged at the outlet end of the furnace bottom gasification agent air inlet in a vertically moving mode. The gasifier can be applied to gasification treatment of carbon-containing organic solids, and solves the problems of poor gasification effect, high tar content, high carbon content in ash and slag and the like of a counter-flow gasifier with coal gas moving in the opposite direction of a material layer.

Description

Sleeve type double oxidation layer fixed bed gasification furnace

Technical Field

The utility model relates to a solid useless processing deals with and the resourceful field, particularly, the utility model relates to a telescopic double oxidation layer fixed bed gasifier.

Background

At present, domestic organic solid waste with higher heat value or treated organic solid waste with higher heat value is treated by a thermochemical conversion mode, and reduction, recycling and harmlessness of the organic solid waste can be realized by the thermochemical conversion mode. The main thermochemical conversion modes include incineration, pyrolysis and gasification, wherein the incineration means that excessive air is introduced to completely oxidize organic solid waste into smoke and ash at high temperature, the heat energy in the high-temperature smoke is converted into electric energy for utilization, and nitrogen, sulfur and chlorine elements contained in the organic solid waste can be converted into polluting gases such as nitrogen oxide, sulfur oxide, hydrogen chloride and the like under the completely oxidizing atmosphere; meanwhile, heavy metals can migrate into the flue gas under the high-temperature oxidation atmosphere. The pyrolysis adopts an anaerobic or anoxic heating mode to crack organic components in the solid waste to generate pyrolysis gas, pyrolysis oil and pyrolysis carbon, and as the organic solid waste components are complex and a large amount of nitrogen, sulfur, chlorine and oxygen elements are transferred into the pyrolysis oil, the pyrolysis oil is difficult to process and utilize economically, and meanwhile, high-concentration organic wastewater is a byproduct; meanwhile, ash in the organic solid waste raw material can be enriched in the pyrolytic carbon.

At present, organic solid waste gasification furnaces are mainly a down-flow gasification furnace in which gas in a material layer moves in the same direction as the material layer and a counter-flow gasification furnace in which gas in the material layer moves in the opposite direction to the material layer. In the forward flow type gasification furnace, materials and a gasifying agent simultaneously enter the furnace body from the upper end, and combustible gas is led out of the furnace body from the lower end, so that the problem of overhigh carbon content of solid-phase slag exists; in the counter-flow gasification furnace, materials enter the furnace body from the upper end, a gasification agent enters the furnace body from the lower end, and combustible gas is led out of the furnace body from the upper end, so that the counter-flow gasification furnace has the problems of high tar content and coal gas leakage at a feed inlet. Therefore, the current organic solid waste gasification furnace still needs to be further improved.

SUMMERY OF THE UTILITY MODEL

The present invention aims at solving at least one of the technical problems in the related art to a certain extent. Therefore, the utility model aims to provide a sleeve type double oxidation layer fixed bed gasification furnace. The gasification furnace can be applied to gasification treatment of carbon-containing organic solids such as household garbage, medical waste, organic hazardous waste, industrial organic solid waste, biomass, coal and the like, and solves the problems of poor gasification effect, high tar content, high carbon content in ash and the like of a counter-flow gasification furnace.

According to the first aspect of the utility model, the utility model provides a sleeve-type double oxidation layer fixed bed gasifier. According to the utility model discloses an embodiment, this gasifier includes:

a feeding device;

the reaction zone furnace body is arranged below the feeding device and comprises a furnace wall and a furnace chamber, the upper section of the furnace chamber is provided with a material distribution device, the middle section of the furnace chamber is provided with a sleeve, the bottom of the furnace chamber is provided with a grate, an annular cavity is formed between the sleeve and the furnace wall, the upper part of the sleeve is of a structure with a wide upper part and a narrow lower part, and the upper end of the sleeve is abutted against the furnace wall;

a furnace top gasification agent inlet, wherein the furnace top gasification agent inlet is arranged at the upper part and/or the top part of the furnace wall and extends into the furnace cavity;

the middle-section gasification agent inlet is arranged in the middle of the furnace wall and is higher than the area where the sleeve is arranged, and the middle-section gasification agent inlet extends into the furnace cavity;

the furnace bottom gasification agent inlet is arranged at the lower part of the furnace wall and is positioned below the grate, and the furnace bottom gasification agent inlet extends into the furnace cavity and is communicated with the lower part of the grate;

the gas outlet is arranged in the middle of the furnace wall and is positioned in the area where the annular cavity is positioned;

the gasification agent distribution regulator is arranged at the outlet end of the furnace bottom gasification agent air inlet in a manner of moving up and down and is positioned in the grate;

and the slag discharging device is arranged below or laterally below the reaction zone furnace body.

The sleeve type double oxidation layer fixed bed gasification furnace of the embodiment of the utility model has the advantages that: 1) the arrangement of the furnace top gasifying agent air inlet, the middle section gasifying agent air inlet and the furnace bottom gasifying agent air inlet can realize the multi-stage supply of the gasifying agent, further realize the stable control of an oxidation layer through the accurate and stable multi-stage oxidation, and fully crack tar in fuel gas, thereby improving the quality of the obtained coal gas and ensuring the lower carbon content of ash slag; 2) the gasification requirements of the carbon-containing organic solids with different volatile matter contents and fixed carbon contents can be met by adjusting the supply amount of the gasification agent at different positions and the position of the middle section gasification agent air inlet; 3) the grate gasifying agent distribution regulator can better adapt to the uniform gas distribution under the condition of small flow of the bottom gasifying agent inlet; 4) the annular cavity formed between the furnace wall and the sleeve can realize the sedimentation of particles in the gas, thereby effectively reducing the content of the particles, meanwhile, the annular cavity area has higher heat, the gas temperature at a gas outlet of the gas is higher, and the secondary combustion is more suitable for being carried out; 5) the gas leakage of the top feed inlet can be avoided by the gas flowing mode of the forward flow of the upper section and the reverse flow of the lower section. In conclusion, the gasification furnace can be applied to gasification treatment of carbon-containing organic solids such as household garbage, medical waste, organic hazardous waste, industrial organic solid waste, biomass, coal and the like, and solves the problems of poor gasification effect, high tar content, high carbon content in solid-phase residue and the like of the counter-flow gasification furnace.

In addition, the sleeve-type double oxidation layer fixed bed gasification furnace according to the above embodiment of the present invention may further have the following additional technical features:

optionally, a plurality of top gasification agent inlets are included, arranged uniformly over the upper part of the furnace wall and/or the top of the furnace wall.

Optionally, a plurality of middle-stage gasification agent inlets are included, and are uniformly and horizontally arranged along the circumferential direction of the furnace wall.

Optionally, a plurality of gas outlets are included, and are uniformly and horizontally arranged along the circumferential direction of the furnace wall.

Optionally, the feeding device comprises at least one feeding channel, each feeding channel is provided with a feeding hole, an upper feeding buffer bin valve, a feeding buffer bin, a lower feeding buffer bin valve and an inert gas purging air inlet from top to bottom in sequence, and a feeding buffer bin pressure charging and discharging opening is formed in the side part of the feeding buffer bin.

Optionally, the top of the furnace wall is connected with the feeding device through a transition bin, the transition bin is communicated with the furnace chamber, and a furnace top gasification agent air inlet is arranged on the side wall of the transition bin.

Optionally, the outside of the furnace wall is a membrane water wall or a jacket water wall.

Optionally, the feeding device comprises two feeding channels, and a communication valve is arranged between the feeding buffer bins of the two feeding channels.

Optionally, the discharge end of the feed channel is communicated with the transition bin and is positioned above the gas inlet of the furnace top gasifying agent.

Optionally, the ratio of the height of the upper end of the sleeve from the lower valve of the feeding buffer bin to the total height of the furnace body in the reaction zone is (0.4-0.8): 1, the ratio of the height of the lower end of the sleeve from the top of the grate to the total height of the furnace body in the reaction zone is (0.2-0.6): 1, the ratio of the height of the sleeve to the inner diameter of the reaction zone furnace body is (0.2-0.6): 1.

optionally, the ratio of the maximum thickness of the annular cavity to the inner diameter of the reaction zone furnace body is 0.1-0.3.

Optionally, the inner diameter of the furnace body of the reaction zone is 0.3-8 m.

Optionally, the membrane water wall is of a shell-and-tube or coil type.

Optionally, the grate can be rotatably arranged, and the grate is provided with a cloth tuyere.

Optionally, the lower part of the furnace wall is of an inverted cone structure, a scraper for crushing ash is arranged in the region, corresponding to the furnace grate, of the furnace wall, a slag outlet is formed at the bottom of the inverted cone structure, and the slag outlet is connected with the slag discharging device.

Optionally, a scraper for crushing ash is arranged on the grate, a slag outlet is formed on the side wall of the lower part of the furnace wall, and the slag outlet is connected with the slag discharging device.

Optionally, the slag discharging device sequentially comprises an upper slag bin valve, a lower slag bin valve and a slag bin pressure charging and discharging port from top to bottom, and the side of the slag bin is provided with a slag bin pressure charging and discharging port.

Optionally, a pressure measuring device and/or a temperature measuring device are further arranged on the reaction zone furnace body, the pressure measuring device is used for detecting the pressure in the reaction zone furnace body, and the temperature measuring device is used for detecting the temperature in the reaction zone furnace body.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural view of a sleeve-type dual oxidation layer fixed-bed gasification furnace according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a sleeve-type dual oxidation layer fixed-bed gasification furnace according to still another embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "thickness", "upper", "lower", "horizontal", "top", "bottom", "inner", "outer", "circumferential", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly, e.g., as meaning permanently connected, detachably connected, or integral to one another; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art. Gasifying agent distribution regulator

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

According to the first aspect of the utility model, the utility model provides a sleeve-type double oxidation layer fixed bed gasifier. According to the embodiment of the utility model, referring to fig. 1 ~ 2, this gasifier includes: the device comprises a feeding device, a reaction zone furnace body, a furnace top gasifying agent air inlet 8, a middle section gasifying agent air inlet 20, a furnace bottom gasifying agent air inlet 14, a coal gas air outlet 11, a gasifying agent distribution regulator 21 and a slag discharging device. The above-mentioned sleeve type double oxidation layer fixed bed gasification furnace will be described in detail with reference to FIGS. 1 to 2.

Feeding device

According to the utility model discloses an embodiment, feed arrangement is suitable for and supplies with organic solid useless to the reaction zone furnace body. As shown in fig. 1 or 2, the feeding device may include at least one feeding channel, each feeding channel is sequentially provided with a feeding hole 6, an upper feeding buffer bin valve 1, a feeding buffer bin 3, a lower feeding buffer bin valve 4 and an inert gas purging air inlet 5 from top to bottom, and a feeding buffer bin pressure relief opening 2 is formed in the side of the feeding buffer bin 3; the feeding device comprises a feeding device, a feeding buffer bin pressure relief opening, a reaction zone furnace body and a plurality of feeding channels, wherein the feeding channels can share one feeding hole, the inert gas purging air inlet is suitable for purging inert gas below the feeding device, and the feeding buffer bin pressure relief opening is suitable for pressurizing or relieving the feeding buffer bin so as to facilitate the organic solid waste to enter the buffer bin or control the pressure in the buffer bin to be consistent with the pressure in the furnace body of the reaction zone so as to facilitate the organic solid waste to enter the furnace chamber; in addition, the upper valve of the feeding buffer bin and the lower valve of the feeding buffer bin can be alternately used, when organic solid waste enters the feeding buffer bin, the upper valve of the feeding buffer bin can be opened, and the lower valve of the feeding buffer bin is closed; when organic solid waste in the feeding buffer bin is supplied to the furnace chamber, the upper valve of the feeding buffer bin can be closed, and the lower valve of the feeding buffer bin is opened.

According to the utility model discloses a specific embodiment, as shown in fig. 1, in single channel feed arrangement, the feed inlet can be for wide conical feed inlet down, and the welding of lower part has circular flange. The feed inlet lower part is the feeding surge bin upper valve, connect through the flange, the feeding surge bin upper valve lower part furnace body is the feeding surge bin, the feeding surge bin lower part is feeding surge bin lower valve, the feeding surge bin upper valve, the feeding surge bin, pass through flange joint between the feeding surge bin lower valve, the feeding surge bin is narrow wide cylindrical structure in the middle of from top to bottom, the feeding surge bin side is equipped with the feeding surge bin and fills the pressure release mouth, the feeding surge bin fills the pressure release mouth horizontal arrangement.

According to another embodiment of the present invention, the inventor found that the gasification furnace can improve gasification intensity and gasification efficiency by pressure gasification, but the material handling capacity per unit time is limited by the diameter of the valve of the feeding port and the intermittent pressure charging and discharging, and the handling capacity can not be improved, and meanwhile, the single-channel feeding pressure charging and discharging process can bring a large amount of dust-containing flue gas to be discharged through the pressure charging and discharging port, for this reason, as shown in fig. 2, it can be preferred that the feeding device comprises two feeding channels a and b, a communication valve 19 can be disposed between the feeding buffer bins 3 of the two feeding channels a and b, in the double-channel feeding device, there are two feeding buffer bins, corresponding upper valves of the feeding buffer bins, lower valves of the feeding buffer bins and inert gas purging air inlets, there are two conical discharge ports at the bottom of the feeding port, and the two conical discharge ports are respectively connected with the upper valves of the two feeding buffer bins through flanges, the lower part of the lower valve of the feeding buffer bin is provided with the feeding buffer bin which is connected through a flange, and a feeding buffer bin gas channel is arranged between the feeding buffer bins and is controlled to be opened and closed through a communicating valve; the side edges of the two feeding buffer bins are respectively provided with a feeding buffer bin pressure charging and releasing hole; the lower part of the feeding buffer bin is connected with a lower valve of the feeding buffer bin through a flange; the lower valve of the feeding buffer bin is a channel connected into the transition bin, and the inert gas purging air inlet is positioned on the channel at the lower part of the lower valve of the feeding buffer bin and horizontally arranged. Through the combination use of feeding surge bin upper valve, feeding surge bin lower valve in intercommunication valve and two feed channel, not only can solve the single channel feeding and fill the problem that the pressure release process can bring a large amount of dusty flue gas, can also improve the organic solid useless supply volume of supplying to in the furnace chamber in the unit interval, solve the limited problem of feeding volume.

A reaction zone furnace body, a furnace top gasification agent air inlet 8, a middle section gasification agent air inlet 20, a furnace bottom gasification agent air inlet 14 and a coal gas air outlet 11

According to the utility model discloses an embodiment, the reaction zone furnace body is established in the feed arrangement below, and the reaction zone furnace body includes oven 22 and the furnace chamber 23 that is formed by the oven, and furnace chamber 23 upper segment is equipped with distributing device 9, the middle section is equipped with sleeve 10, the bottom is equipped with grate 13, is formed with annular cavity 24 between sleeve 10 and the oven 22, and sleeve 10 upper portion is narrow structure and sleeve 10's upper end in oven 22 under the upper width. The top gasification agent gas inlet 8 is arranged on the upper part and/or the top of the furnace wall 22 and extends into the furnace chamber 23; the middle section gasification agent inlet 20 is arranged in the middle of the furnace wall 22 and higher than the area where the sleeve 10 is arranged, and extends into the furnace chamber 23; the bottom gasification inlet 14 is provided at a lower portion of the furnace wall 22 below the grate 13, and may be provided at a lower end of a bottom wall or a side wall of the furnace wall 22, for example, and the bottom gasification inlet 22 may extend into the furnace chamber 23 and communicate with a lower portion of the grate 13. The gas outlet 11 is arranged in the middle of the furnace wall 22 in the region of the annular cavity 24. Therefore, not only can the multi-stage supply of the gasifying agent be realized, but also the stable control of the double oxidation layer can be realized through accurate and stable multi-stage oxidation, so that the tar in the fuel gas is fully cracked, the quality of the obtained gas is improved, and the carbon content of ash slag is reduced; in addition, the supply amount of the gasification agent at different positions and the position of the middle section gasification agent air inlet can be adjusted to meet the gasification requirements of the carbon-containing organic solid with different volatile matter contents and fixed carbon contents; the grate gasifying agent distribution regulator can better adapt to the uniform air distribution under the condition of small flow of the bottom gasifying agent air inlet so as to meet the requirement of uniform air distribution in the gasifier under the condition of small load operation; the annular cavity formed between the furnace wall and the sleeve can realize the sedimentation of particles in the fuel gas (namely, coal gas), thereby effectively reducing the content of the particles in the fuel gas product, and simultaneously, because the annular cavity does not have high-temperature reaction of a carbon layer, the fuel gas can also achieve the effect of cooling when being led out through the annular cavity; the gas flowing mode of the upper section concurrent flow and the lower section countercurrent flow can avoid the gas leakage at the top feed inlet because the gasification agent is arranged at the two sections of the gasification furnace, which is the advantage that the traditional gasification furnace does not have; moreover, the upper part of the sleeve is of a structure with a wide upper part and a narrow lower part, and the upper end of the sleeve is abutted against the furnace wall, so that the sleeve and the furnace wall are relatively fixed, and a sealing structure can be formed at the top of the annular cavity, so that the separation of gas and particles can be better realized, and the gas is prevented from outputting and carrying excessive particles; preferably, a water wall structure can be formed outside the sleeve and the furnace wall of the upper area of the sleeve, so that the dry distillation semicoke falls along the inner wall of the sleeve, the phenomenon that part of organic solid waste is coked and hung on the furnace wall due to high temperature of the furnace wall is avoided, and the better cooling effect is achieved in the process that fuel gas is led out from the annular cavity. The sleeve type double oxidation layer fixed bed gasification furnace can be applicable to the organic solid waste treatment with high tar content.

According to the embodiment of the utility model, can utilize furnace roof gasification agent air inlet, middle section gasification agent air inlet and stove bottom gasification agent air inlet to supply with the gasification agent to the reaction zone furnace body, divide into drying layer, dry distillation layer, go up the oxide layer, reduction layer, oxide layer and ash residue layer down with the reaction zone furnace body from top to bottom, make organic solid useless gasification reaction that takes place, obtain combustible gas and lime-ash, the combustible gas passes through the toroidal cavity discharge reaction zone furnace body between sleeve and the oven, wherein, the combustible gas can be coal gas. Wherein, the pressure in the reaction zone furnace body can be 0-10 MPa, for example 0-3 MPa, the pressure of the gasification agent in the gas inlet can also be 0-10 MPa, for example 0-3 MPa, and the pressure can be the relative pressure measured by a pressure instrument. In addition, through the control of the air inflow of each stage of gasifying agent, the drying layer, the dry distillation layer and the upper oxidation layer can be positioned above the sleeve, the lower oxidation layer and the ash layer are positioned below the sleeve, and the whole sleeve area is positioned in the reduction layer.

According to an embodiment of the present invention, a plurality of top gasification agent inlets 8 may be included, and as shown in fig. 1, the plurality of top gasification agent inlets 8 may be uniformly arranged on the upper portion of the side wall of the furnace wall 22 and/or the top of the furnace wall 22. Further, as shown in fig. 2, a transition bin 7 may be disposed at the top of the furnace wall 22, the top of the furnace wall 22 is connected to the feeding device through the transition bin 7, the transition bin 7 is communicated with the furnace chamber 23, and a furnace top gasifying agent inlet may be disposed on the side wall of the transition bin 7, wherein the furnace top gasifying agent inlet disposed on the transition bin 7 may be symmetrically disposed along the circumferential direction of the transition bin, the discharge end of the feeding channel may be communicated with the transition bin 7 and located above the furnace top gasifying agent inlet, for example, a lower valve of the feeding buffer bin is connected to a discharge channel connected to the transition bin, an inert gas purging inlet may be located on the discharge channel, and uniform air distribution at the top of the furnace body may be achieved by using a cavity formed in the transition bin region and the plurality of furnace top gasifying agent inlets.

According to the utility model discloses a still another embodiment can include one or more middle section gasification agent air inlet 20, and a plurality of middle section gasification agent air inlets 20 can be evenly arranged, the level along oven 22's circumference, and wherein middle section gasification agent air inlet can be used to regulate and control the top oxide layer position, avoids appearing the top oxide layer too high or low problem of crossing, and the preferred top oxide layer that makes is located the sleeve top.

According to another embodiment of the present invention, one or more gas outlets 11 may be included, and a gas outlet may be preferably provided in consideration of the fact that a large number of gas outlets may cause the structure of the gasification furnace to be more complicated; in order to avoid the furnace type structure being too complex, when a plurality of gas outlets are arranged, the number of the gas outlets can be preferably 2 or 3, and at the moment, the plurality of gas outlets 11 can be uniformly and horizontally arranged along the circumferential direction of the furnace wall 22, so that uniform gas outlet can be effectively realized, and the problem of nonuniform reaction of the furnace layer caused by the gas outlets on one side is avoided.

According to the utility model discloses a still another embodiment, the ratio of the height of sleeve 10 upper end distance feeding surge bin lower valve 4 and reaction zone furnace body overall height can be (0.4 ~ 0.8): 1, the ratio of the height from the lower end of the sleeve 10 to the top of the grate 13 to the total height of the furnace body in the reaction zone can be (0.2-0.6): 1, the ratio of the height of the sleeve 10 to the inner diameter of the reaction zone furnace body can be (0.2-0.6): 1. therefore, the annular cavity formed between the sleeve and the furnace wall can be ensured to have enough height, so that the combustible gas product is further cooled, sufficient settling space is provided for particles in the combustible gas, and the particles in the combustible gas are reduced; and carbon dioxide generated by the oxidation layer can react with the carbon layer of the reduction section to generate required carbon monoxide, and the carbon dioxide and the carbon layer can have reasonable reaction contact time by controlling the distance range between the end part of the sleeve and the grate.

According to another embodiment of the present invention, the ratio of the maximum thickness of the annular cavity 24 to the inner diameter of the reaction zone can be (0.1-0.3): the inventor finds that if the thickness of the annular cavity is too large, the reaction space in the furnace can be reduced, so that the treatment capacity of the gasification furnace is obviously reduced, and if the thickness of the annular cavity is too small, the annular cavity is not beneficial to sedimentation of particles and is also beneficial to maintenance of the sleeve by workers; in addition, the inner diameter of the furnace body of the reaction zone can be 0.3-8 m, and the skilled person can select the inner diameter according to actual needs. It should be noted that the sleeve 10 includes an upper cylinder with a wide upper diameter and a narrow lower diameter and a lower cylinder with a uniform upper diameter and a uniform lower diameter, and the maximum thickness of the annular cavity refers to the thickness of the annular cavity corresponding to the lower cylinder of the sleeve.

According to another embodiment of the present invention, the outer side of the furnace wall 22 is a membrane wall, which can be connected to the top end of the upper furnace body by a flange, and the membrane wall can be a coil type or a tube type; the furnace can also be a jacket water-cooled wall, so that the radiation of high temperature in the furnace to the outside can be avoided, the slag bonding phenomenon on the inner wall of the furnace can also be avoided, and the operation of the furnace body is more stable; in addition, to avoid the problem of bulging by means of a water jacket, the membrane wall may preferably be of the coil or tube type.

According to the utility model discloses a still another concrete embodiment, the reaction zone furnace body can be the cylinder shape, settles in the furnace chamber under feed arrangement transition bin has the distributing device, the internal diameter of reaction zone furnace body 0.3 ~ 8.0 m. As shown in fig. 1, an inert gas purging gas inlet is horizontally arranged at the top of the furnace body at the lower part of the feeding buffer bin, more than one furnace top gasifying agent gas inlet is arranged in the area above the top wall or the side wall of the furnace body at the lower part of the inert gas purging gas inlet, a plurality of furnace top gasifying agent gas inlets are uniformly arranged along the circumferential direction when positioned on the side edge, and are uniformly arranged in a ring shape when positioned at the top, and uniform gas distribution is realized through the plurality of furnace top gasifying agent gas inlets and a cavity area in the top of the gasification furnace body; or, as shown in fig. 2, the lower part of the lower valve of the feeding buffer bin is a channel connected to the transition bin, the inert gas purging gas inlets are horizontally arranged on the channel at the lower part of the lower valve of the feeding buffer bin, a plurality of furnace top gasifying agent gas inlets are arranged on the side wall of the transition bin, and the plurality of furnace top gasifying agent gas inlets are uniformly or symmetrically arranged along the circumferential direction. The uniform air distribution is realized through a plurality of furnace top gasifying agent air inlets, cavity areas in the feeding buffer bin and/or transition bin cavities, and the introduced gasifying agent is water vapor, carbon dioxide, air, oxygen-enriched air (with the oxygen concentration of 21-100 percent) and mixed gas of the four gases in different proportions. Wherein, the sleeve accessible is fixed with the mode of stove inner wall welded, and the middle section gasification agent air inlet has been arranged to sleeve top region, and this middle section gasification agent air inlet arranges that the quantity is one to a plurality of.

Gasifying agent distribution regulator 21 and slag discharge device

According to the embodiment of the present invention, as shown in fig. 1 or 2, a gasifying agent distribution adjuster 21 is provided at the outlet end of the bottom gasifying agent inlet 14 so as to be movable up and down and is located in the cavity formed by the grate 21, and the gasifying agent distribution adjuster is used for adjusting the distribution of the gasifying agent in the grate; the slag discharging device can be arranged below or laterally below the reaction zone furnace body and is used for discharging ash slag out of the reaction zone furnace body in a central slag discharging or lateral slag discharging mode.

According to the utility model discloses an embodiment, the grate 13 can rotatable setting, can be formed with the cloth wind mouth on the grate 13, can further realize the even cloth wind of stove bottom air inlet from this.

According to another embodiment of the present invention, the bottom end of the grate is provided with a bottom gasifying agent inlet 14 communicated with the grate 13, an ash discharging channel is arranged under or laterally below the grate 13, and the bottom gasifying agent inlet 14 is connected with an external air source through a pipeline positioned under or laterally below the grate 13; the bottom of the furnace wall 22 on the grate 13 or on two sides of the grate can be welded with a scraper 25 to crush the ash, the grate 13 is distributed with gas distribution ports to realize the uniform gas distribution of the furnace bottom gasification agent, and the introduced agent is water vapor, carbon dioxide, air, oxygen enrichment (the oxygen concentration is 21-100 v%) and mixed gas of the four gases in different proportions.

According to the utility model discloses a concrete embodiment, as shown in FIG. 1, the sediment mode can be for the center row's sediment, the lower part of oven 22 can be the back taper structure this moment, the region that corresponds with grate 13 on the oven 22 can be equipped with the scraper 25 that is used for broken lime-ash, the bottom of back taper structure is formed with the slag notch, the slag notch links to each other with row's sediment device, therefore, the grate can drive rotatoryly through the motor, the lime-ash on top ash layer is realized the breakage of lime-ash by the scraper, avoid bold lime-ash to block up, the lime-ash gets into row's sediment device under the action of gravity through the center slag notch of grate below by the broken back center of grate along the below.

According to another embodiment of the present invention, as shown in fig. 2, the slag discharging mode can be side slag discharging, the grate 13 can be provided with a scraper 25 for breaking ash, the sidewall of the lower portion of the furnace wall 22 can be formed with a slag hole, and the slag hole is connected to the slag discharging device. From this, grate accessible motor drives rotatoryly, and the scraper that has on the grate can realize the breakage of lime-ash, avoids massive lime-ash to block up, and the lime-ash gets into the sediment device through rotatory extrusion through the slag notch of side by the broken back of grate.

According to another embodiment of the present invention, as shown in fig. 1 or 2, the slag discharging device can sequentially include an upper slag bin valve 15, a lower slag bin valve 16, and a lower slag bin valve 17 from top to bottom, and the side of the slag bin 16 can be provided with a slag bin pressure charging and discharging opening 18. Wherein, the reactor furnace body slag notch below is valve on the sediment storehouse, and the furnace body bottom passes through flange joint with the sediment storehouse, goes up through flange joint between valve and the sediment storehouse in the sediment storehouse, and the sediment storehouse is narrow wide cylindrical structure in the middle of from top to bottom for collect the lime-ash, the sediment storehouse is down the valve and passes through flange joint with the sediment storehouse.

According to the embodiment of the utility model, can further be equipped with pressure measurement device and/or temperature measuring device on the reaction zone furnace body, pressure measurement device can be used for detecting the pressure in the reaction zone furnace body, temperature measuring device can be used for detecting the temperature in the reaction zone furnace body, can adjust the inlet pressure of gasification agent according to pressure measurement device's demonstration from this, the feed pressure in the feeding surge bin during the feeding with arrange the pressure in the sediment storehouse during row sediment, the gasification agent air input of different air inlets is adjusted according to temperature measuring device's demonstration, thereby more be favorable to realizing that the furnace body is stable, and can accurate stable realization oxide layer's control.

To sum up, the sleeve-type dual-oxidation-layer fixed bed gasification furnace of the embodiment of the utility model has the following advantages: 1) the arrangement of the furnace top gasifying agent air inlet, the middle section gasifying agent air inlet and the furnace bottom gasifying agent air inlet can realize the multi-stage supply of the gasifying agent, further realize the stable control of an oxidation layer through the accurate and stable multi-stage oxidation, and fully crack tar in the fuel gas, thereby improving the quality of the obtained combustible gas and ensuring the lower carbon content of ash slag; 2) the gasification requirements of the carbon-containing organic solids with different volatile matter contents and fixed carbon contents can be met by adjusting the supply amount of the gasification agent at different positions and the position of the middle section gasification agent air inlet; 3) the grate gasifying agent distribution regulator can better adapt to the uniform gas distribution under the condition of small flow of the bottom gasifying agent inlet; 4) the annular cavity formed between the furnace wall and the sleeve can realize the sedimentation of particles in the gas, thereby effectively reducing the content of the particles, meanwhile, the annular cavity area has higher heat, the gas temperature at a gas outlet of the gas is higher, and the secondary combustion is more suitable for being carried out; 5) the safety of the operation of the gasification furnace can be effectively ensured by the aid of the charging and discharging designs of the inert gas purging gas inlet, the feeding buffer bin and the slag bin; 6) the gas leakage of the top feed inlet can be avoided by the gas flowing mode of the forward flow of the upper section and the reverse flow of the lower section. In conclusion, the gasification furnace can be applied to gasification treatment of carbon-containing organic solids such as household garbage, medical waste, organic hazardous waste, industrial organic solid waste, biomass, coal and the like, and solves the problems of poor gasification effect, high tar content, high carbon content in solid-phase residue and the like in the prior art.

In order to facilitate understanding of the sleeve-type dual oxidation layer fixed bed gasification furnace according to the embodiment of the present invention, a method for performing organic solid waste gasification using the sleeve-type dual oxidation layer fixed bed gasification furnace will be described in detail. According to the utility model discloses an embodiment, this method includes: feeding organic solid waste to a reaction zone furnace body by using a feeding device; purging inert gas below the feeding device through an inert gas purging gas inlet; supplying a gasification agent to the reaction zone furnace body by utilizing a furnace top gasification agent air inlet, a middle section gasification agent air inlet and a furnace bottom gasification agent air inlet, and dividing the reaction zone furnace body into a drying layer, a dry distillation layer, an upper oxidation layer, a reduction layer, a lower oxidation layer and an ash layer from top to bottom; gasifying organic solid waste to obtain gas, combustible gas and ash; the combustible gas of the coal gas is discharged out of the furnace body of the reaction zone through the annular cavity between the sleeve and the furnace wall; the ash slag is discharged out of the furnace body of the reaction zone by a slag discharge device. The method can be applied to gasification treatment of carbon-containing organic solids such as household garbage, medical waste, organic hazardous waste, industrial organic solid waste, biomass, coal and the like, and solves the problems of poor gasification effect, high tar content, high carbon content in solid-phase residue and the like of a counter-flow gasification furnace.

According to a specific embodiment of the present invention, a pressure may exist in the reaction zone furnace body, and the pressure range may be 0 to 10Mpa, for example, 0 to 3Mpa, 0.1Mpa, 1Mpa, 2Mpa, 3Mpa, 4Mpa, 5Mpa, 6Mpa, 7Mpa, 8Mpa, 9Mpa, 10Mpa, etc. By pressurizing the gasification furnace, the gasification strength and gasification efficiency of the organic solid waste can be further improved.

According to the utility model discloses a specific embodiment, the gasification agent that the gasifier adopted can include at least one of steam, carbon dioxide, air and oxygen boosting, and wherein the content of oxygen in the oxygen boosting is 21 ~ 100 v% to make organic solid useless partial oxidation take place and realize self-heating, make organic component fracture into noncondensable micro molecule gas as far as possible simultaneously, obtain the combustible gas.

According to a specific embodiment of the utility model, the gasification agent can be the gas mixture of vapor and oxygen boosting, and the quality of vapor can be 0 ~ 8.0Kg/Nm with the specific value of oxygen volume in the oxygen boosting³For example, it may be 0Kg/Nm³、0.1Kg/Nm³、0.5Kg/Nm³、1.0Kg/Nm³、2.0Kg/Nm³、3.0Kg/Nm³、4.0Kg/Nm³、5.0Kg/Nm³、6.0Kg/Nm³、7.0Kg/Nm³、8.0Kg/Nm³And the like. The inventors have found that when the gasifying agent is steam andwhen the oxygen-enriched mixed gas is used, the ratio of the mass of the water vapor to the volume of the oxygen in the oxygen-enriched mixed gas is controlled to be in the range, so that the gasification temperature of the materials with different ash melting points can be maintained below the softening point temperature of the ash, and the ash slag is prevented from being bonded to influence the normal operation of the gasification furnace. Preferably, the ratio of the mass of the water vapor to the volume of the oxygen in the enriched oxygen can be set to 1.0-6.0 Kg/Nm³. More preferably, the ratio of the mass of water vapour to the volume of oxygen in the enriched oxygen may be set to about 2.0Kg/Nm at a gasification pressure set to 100KPa³(ii) a When the gasification pressure is set to 2MPa, the ratio of the mass of the water vapor to the volume of oxygen in the enriched oxygen can be set to about 5.0Kg/Nm³. If the ratio of the mass of the water vapor to the volume of the oxygen in the rich oxygen is too large, the gasification reaction temperature may be reduced, the content of effective components such as carbon monoxide and hydrogen in the coal gas is reduced, and the heat value of the coal gas is reduced. If the ratio of the mass of the water vapor to the volume of the oxygen in the rich oxygen is too small, the gasification reaction temperature may be raised to make the temperature of the oxidation layer higher than the softening point temperature of the ash, so that the ash slagging gasification furnace cannot normally operate.

According to another embodiment of the present invention, the gasifying agent can be a mixture of steam and air, the temperature of the gasifying agent can be 40-70 ℃, for example, 40 ℃, 50 ℃, 60 ℃ or 70 ℃, and the inventors found that, when the mixture of steam and air is used as the gasifying agent, the temperature of the gasifying agent is controlled in the above range, so that the air can bring a proper amount of steam into the redox layer of the gasification furnace to cause the water gas reaction between carbon and steam, thereby generating carbon monoxide and hydrogen. If the temperature of the gasifying agent is too low, the amount of water vapor possibly brought in is less, so that the temperature of an oxidation layer is too high, and if the temperature is higher than the softening point temperature of ash, serious slagging phenomenon can be caused, and the normal operation of the gasification furnace is influenced; if the temperature of the gasifying agent is too high, the amount of water vapor possibly brought in is too small, and the reaction temperature is too low, so that the quality of the coal gas is reduced.

According to the utility model discloses a still another concrete example, the gasification agent can be the gas mixture of carbon dioxide and oxygen boosting, and the quality of carbon dioxide can be 0 ~ 19.5Kg/Nm with the specific value of oxygen volume in the oxygen boosting³For example, it may be 0Kg/Nm³、0.1Kg/Nm³、0.5Kg/Nm³、1.0Kg/Nm³、2.0Kg/Nm³、3.0Kg/Nm³、5.0Kg/Nm³、8.0Kg/Nm³、10.0Kg/Nm³、12.0Kg/Nm³、15.0Kg/Nm³、16.0Kg/Nm³、18.0Kg/Nm³、19.5Kg/Nm³And the like. The inventor finds that when the mixed gas of carbon dioxide and oxygen-enriched air is adopted as the gasifying agent, the ratio of the mass of the carbon dioxide to the volume of the oxygen in the oxygen-enriched air is controlled to be in the range, so that the carbon dioxide and the carbon can be subjected to reduction reaction to generate carbon monoxide, the heat of a reaction layer is absorbed, the temperature of the reaction layer is maintained in a reasonable range, and the quality of coal gas and slag bonding of ash are kept. Preferably, the ratio of the mass of the carbon dioxide to the volume of the oxygen in the enriched oxygen can be set to be 1.0-15.0 Kg/Nm³. More preferably, the ratio of the mass of carbon dioxide to the volume of oxygen in the enriched oxygen can be set to about 6.0Kg/Nm at a gasification pressure set at 100KPa³(ii) a When the gasification pressure is set to 2MPa, the ratio of the mass of the water, carbon dioxide and the volume of the oxygen in the oxygen-enriched air can be set to be about 14.0Kg/Nm³. If the ratio of the mass of carbon dioxide to the volume of oxygen in the enriched oxygen is too large, the temperature of the reaction layer may be reduced too much, resulting in poor gas quality.

According to the utility model discloses a specific embodiment, the air input of furnace roof gasification agent air inlet and middle section gasification agent air inlet can be for 30 ~ 90% (for example can be 30%, 40%, 50%, 60%, 70%, 80%, 90% etc.) of the total air input of gasification agent, the air input of stove bottom gasification agent air inlet can be for 10 ~ 70% (for example 10%, 20%, 30%, 40%, 50%, 60%, 70% etc.) of the total air input of gasification agent, the air input proportion of furnace roof gasification agent air inlet and middle section gasification agent air inlet can be (70 ~ 90%): (10-30%), for example, 70/30, 80/20, 90/10, 75/25, 85/15, etc. By controlling the air input of the gasifying agent at each air inlet of the gasification furnace within the range, the volatile matter in the upper oxidation layer, which generates tar, can be directly oxidized into coal gas by the oxygen in the gasifying agent, thereby avoiding the generation of tar, and simultaneously, the carbon in the lower oxidation layer is oxidized by the oxygen in the gasifying agent and the coal gas is generated by the reaction of water gas.

According to an embodiment of the present invention, the temperature of the drying layer and the dry distillation layer may be 200 to 600 ℃ (e.g., 200 ℃, 250 ℃, 300 ℃, 350 ℃, 400 ℃, 450 ℃, 500 ℃, 550 ℃, 600 ℃, etc.), the temperature of the upper oxidation layer may be 600 to 1200 ℃ (e.g., 600 ℃, 700 ℃, 800 ℃, 900 ℃, 1000 ℃, 1100 ℃, 1200 ℃, etc.), the temperature of the reduction layer may be 600 to 900 ℃ (e.g., 600 ℃, 650 ℃, 700 ℃, 750 ℃, 800 ℃, 850 ℃, 900 ℃, etc.), the temperature of the lower oxidation layer may be 600 to 1100 ℃ (e.g., 600 ℃, 700 ℃, 800 ℃, 900 ℃, 1000 ℃, 1100 ℃, etc.), and the temperature of the ash layer may be 200 to 600 ℃ (e.g., 200 ℃, 250 ℃, 300 ℃, 350 ℃, 400 ℃, 450 ℃, 500 ℃, 550 ℃, 600 ℃, etc.); the temperature in the annular cavity may be 200 to 800 ℃ (e.g., 200 ℃, 300 ℃, 400 ℃, 500 ℃, 600 ℃, 700 ℃, 800 ℃, etc.). By controlling the temperature of each reaction area in the gasification furnace within the range, the reaction layer of the oxidation layer can maintain reasonable reaction temperature, the quality of coal gas is ensured, and meanwhile, the reaction temperature of ash is lower than the softening point, and no slagging occurs.

It should be noted that the features and effects described for the sleeve-type dual oxidation layer fixed bed gasification furnace are also applicable to the method for gasifying organic solid waste, and are not described in detail herein.

The invention will now be described with reference to specific examples, which are intended to be illustrative only and not to be limiting in any way.

Example 1

The sleeve type double oxidation layer fixed bed gasification furnace adopts a single-channel feeding and central deslagging design, and the structure of the sleeve type double oxidation layer fixed bed gasification furnace is shown in figure 1, wherein in figure 1: 1-feeding buffer bin upper valve, 2-feeding buffer bin pressure charging and discharging port, 3-feeding buffer bin, 4-feeding buffer bin lower valve, 5-inert gas purging air inlet, 6-feeding port, 8-furnace top gasifying agent air inlet, 9-distributing device, 10-sleeve, 11-coal gas outlet, 12-membrane water cooling wall, 13-furnace grate, 14-furnace bottom gasifying agent air inlet, 15-slag bin upper valve, 16-slag bin, 17-slag bin lower valve, 18-slag bin pressure charging and discharging port, 20-middle section gasifying agent air inlet, 21-furnace grate gasifying agent distribution regulator, 22-furnace wall (gasifying furnace body), 23-furnace chamber, 24-annular cavity and 25-scraper.

1) Feeding of the feedstock

The organic solid waste gasification furnace of the embodiment is composed of a conical feed inlet 6, a cylindrical feed buffer bin 3 with a narrow upper part and a narrow middle part and a cylindrical gasification furnace body, wherein a feed buffer bin upper valve 1 is arranged between the feed inlet 6 and the feed buffer bin 3 and is connected through a flange. Install feeding surge bin lower valve 4 between feeding surge bin 3 and the gasification furnace body to through flange joint, 3 sides in feeding surge bin are equipped with feeding surge bin and fill pressure release mouth 2. The material gets into the gasifier from feed inlet 6, there is certain pressure in the stove this moment, feeding surge bin lower valve 4 keeps the encapsulated state, open feeding surge bin upper valve 1 and make the material in the feed inlet enter into feeding surge bin 3, feeding surge bin 3 is in the normal pressure state this moment, close feeding surge bin upper valve 1 after adding the material in feeding surge bin 3, realize feeding surge bin 3's sealed, fill pressure release mouth 2 through feeding surge bin and pressurize this moment, make pressure in feeding surge bin 3 unanimous with the interior pressure of reacting furnace, sweep air inlet 5 through feeding surge bin lower valve 4 lower part and let in nitrogen gas, vapor or carbon dioxide, make feeding surge bin lower valve 4 lower part atmosphere be the incombustible gas, open feeding surge bin lower valve 4, make the material in feeding surge bin 3 get into gasification reaction zone under the effect of gravity and gasify. The material closes feeding surge bin lower valve 4 after getting into the gasification district completely in feeding surge bin 3, fills pressure release mouth 2 through feeding surge bin and carries out feeding surge bin 3 pressure releases, reaches the ordinary pressure state, opens feeding surge bin upper valve 3 and opens new round of feeding.

2) Gasification agent inlet gas

Be equipped with three gasification agent air inlets in furnace body 22, firstly furnace roof gasification agent air inlet 8 is located inert gas and sweeps the top of 5 below gasification furnace bodies 22 of air inlet, and the annular evenly is provided with a plurality ofly, realizes the even gas distribution in top through symmetrical arrangement. And secondly, the middle section gasification agent air inlet 20 is horizontally arranged in the upper area of the middle section of the furnace body and is horizontally arranged along the circumferential direction. And the third is a bottom gasifying agent inlet 14 which is communicated with the bottom grate 13, the bottom is uniformly distributed through a gas distribution port of the grate 13, and a grate gasifying agent distribution regulator 21 is arranged in the grate 13. The even gas distribution of the air inlet that furnace body top and grate 13 formed from top to bottom can ensure that the material forms even stable reaction layer in gasification reaction zone, avoids the phenomenon of inhomogeneous reaction. The middle section gasifying agent inlet 20 is used for controlling the position of the upper oxidation layer, so that the problem that the upper oxidation layer is too high or too low is avoided, when the calorific value of the gasified raw material is lower or the fixed carbon content is lower, the gasifying agent feeding amount demand of the furnace bottom gasifying agent inlet 14 is less, and the small-flow uniform gas distribution is realized by reducing and adjusting the height of the grate gasifying agent distribution adjuster 21. The gasification agents introduced into the three gasification agent inlets are rich oxygen (oxygen concentration is 100%) and steam.

3) Gasification process

The gasifier body 22 of the organic solid waste gasifier of the present embodiment is a main gasification reaction region, and the sleeve 10 is installed in the middle section, and can be divided into a drying layer, a dry distillation layer, an upper oxidation layer, a reduction layer, a lower oxidation layer, and an ash layer from top to bottom. The drying layer and the dry distillation layer are positioned on the upper part of the sleeve 10, the upper oxidation layer is positioned on the upper part of the sleeve 10, the sleeve is positioned in the reduction layer area, the lower end of the sleeve 10 is a boundary of the upper reduction layer and the lower reduction layer, and the lower oxidation layer and the ash layer are positioned on the lower part of the sleeve 10. The material is from feeding surge bin 3 entering gasifier 22 in, realizes the even cloth of material on the dry layer by distributing device 9, and the dry layer temperature is in 20 ~ 200 ℃ within range, and the moisture in the material is heated the evaporation and enters into the gaseous phase, and the material through drying gets into the dry distillation layer and releases the volatile matter, generates tar and semicoke, and the temperature on dry distillation layer is in 200 ~ 600 ℃ within range. The tar and the semicoke enter the upper oxidation layer, the tar and the semicoke are subjected to oxidation reaction with oxygen in the gasifying agent to release heat, so that the temperature of the upper oxidation layer can reach 600-1200 ℃, meanwhile, part of the tar is cracked in a high-temperature area, the semicoke is only partially subjected to oxidation reaction due to insufficient gas-solid contact, the semicoke mainly enters the reduction layer under the action of gravity of the material, and carbon dioxide and water generated by oxidation of the upper oxidation layer and the semicoke in the reduction layer are subjected to gasification reaction, so that the quality of coal gas is improved. The semicoke which is not reacted in the reduction layer enters the lower oxidation layer and is further oxidized with the gasification agent introduced from the gasification agent inlet 14 at the bottom of the furnace, and the heat is released by the water gas reaction. The heat of the reduction layer comes from the heat transfer of the upper oxidation layer and the lower oxidation layer, the temperature range is 600-900 ℃, and the temperature range of the lower oxidation layer is 600-1100 ℃. The semicoke becomes the lime-ash and gets into the ash layer above the grate 13 after the oxidizing layer takes place complete oxidation reaction under, and the ash layer temperature range is within 200 ~ 600 ℃, and the grate 13 passes through the motor and drives rotatoryly, realizes the breakage of slag by scraper 25 with the lime-ash on the ash layer of top, avoids bold lime-ash to block up, and the lime-ash gets into slag silo 16 through the collection mouth of grate 13 below. The gasification agent introduced into the air inlet of the furnace bottom gasification agent enters the ash layer through the air holes of the grate to exchange heat with the ash so as to heat the gasification agent and cool the ash.

4) Slag discharge

The slag bin 16 below the furnace body is alternately discharged with ash, the lower valve 17 of the slag bin is in a closed state, the upper valve 15 of the slag bin is in an open state, ash and slag are crushed by the grate and enter the slag bin 16 along the central collecting port below under the action of gravity, then the upper valve 15 of the slag bin is closed, the pressure relief port 18 is filled through the slag bin, the pressure relief enables the pressure of the slag bin 16 to be changed into a normal pressure state, the lower valve 17 of the slag bin is opened to discharge the ash and slag, then the lower valve 17 of the slag bin is closed, the pressure relief port 18 is filled through the slag bin to be the same as the pressure in the furnace, and then the upper valve 15 of the slag bin is opened to enable the ash and slag on the ash layer to enter the slag bin 16 to discharge a new round.

5) Air outlet

The sleeve 10 is arranged below the upper oxidation layer and the middle upper part of the reduction layer in the middle section of the furnace body, an interlayer is arranged between the sleeve 10 and the gasification furnace body 22, an annular cavity 24 can be formed in the region after the filling materials start to react, a coal gas outlet 11 is arranged in the annular cavity region, the annular cavity region is horizontally and uniformly arranged along the circumferential direction, uniform air outlet can be effectively realized, and the problem of nonuniform reaction of the furnace layer caused by a single-side gas outlet is avoided. The material below the annular cavity plays a role in filtering, and particulate matters in the fuel gas are reduced. Meanwhile, the cavity is radiated by the upper oxidation layer and the reduction layer to have higher temperature, and the gas carrying tar passes through the upper oxidation layer, the reduction layer and the outer annular cavity of the sleeve within the range of 200-800 ℃, so that the tar can be fully cracked and gasified at high temperature, and finally the combustible gas with low tar, low particles and high calorific value is obtained from the gas outlet 11.

The outer layer of the gasification furnace body 22 is a membrane water wall 12, the membrane water wall 12 is used for preventing the furnace body from generating high-temperature outward radiation heat, and simultaneously effectively preventing coking and coke hanging phenomena caused by high temperature in the furnace, and simultaneously, compared with the traditional mode of adopting a water jacket, the method can effectively avoid the problem of bulging.

The following concrete examples of the operation of the gasification furnace are as follows:

the inner diameter of the gasification furnace is 3.2m, the processed materials are biomass, and the processing amount is 6400 Kg/h. The main operating conditions and gasification results were as follows:

(1) industrial analysis of materials is shown in the following Table

	Mt(％)	Mad(％)	Aad(％)	Vad(％)	Qnet,ar(MJ/kg)
						Biomass	5.00	3.16	2.59	75.59	18.25

(2) The operating conditions are as follows:

gasification pressure: atmospheric pressure

Gasifying agent: oxygen-rich (oxygen concentration 100%) + water vapor

Oxygen amount: 950Nm³/h

Amount of water vapor: 1900Kg/h

(3) And (3) gasification result:

gas production: 8450Nm³/h

The fuel gas comprises the following components: h₂：24.39％，CO：50.02％，CH₄：3.32％，CO₂：19.97％，N₂：1.29％，O₂：0.65％，C_nH_m：0.36％。

Gasification efficiency: 76 percent of

Carbon content of ash: 2.8 percent of

The tar content of the fuel gas is as follows:<1g/Nm³

example 2

The sleeve type double oxidation layer fixed bed gasification furnace adopts a double-channel feeding and side deslagging design, and the structure of the sleeve type double oxidation layer fixed bed gasification furnace is shown in figure 2, wherein in figure 2: 1-feeding buffer bin upper valve, 2-feeding buffer bin pressure charging and releasing port, 3-feeding buffer bin, 4-feeding buffer bin lower valve, 5-inert gas purging air inlet, 6-feeding port, 7-transition bin, 8-furnace top gasifying agent air inlet, 9-material distribution device, 10-sleeve, 11-gas air outlet, 12-membrane water-cooled wall, 13-furnace grate, 14-furnace bottom gasifying agent air inlet, 15-furnace wall upper valve, 16-slag bin, 17-slag bin lower valve, 18-slag bin pressure charging and releasing port, 19-feeding buffer bin communicating valve, 20-middle section gasifying agent air inlet, 21-furnace grate gasifying agent distribution regulator, 22-furnace body, 23-furnace chamber, 24-annular cavity and 25-scraper.

1) Feeding of the feedstock

The gasification furnace of the embodiment consists of a double-channel feeding device, a gasification furnace body and a side deslagging device. The double-channel feeding device consists of an upper valve 1 of a feeding buffer bin, a lower valve 4 of the feeding buffer bin, a pressure charging and releasing port 2 of the feeding buffer bin, a feeding buffer bin 3, a lower valve 4 of the feeding buffer bin, an inert gas purging air inlet 5, a feeding port 6 at the top and a feeding buffer bin communicating valve 19 between the feeding buffer bins. The double-channel feeding work flow is that when feeding surge bin 3a is in the ordinary pressure state, feeding surge bin communicating valve 19 and feeding surge bin lower valve 4a are in the closed state, and feeding surge bin upper valve 1a is in the open state, and the material enters into feeding surge bin 3a through feeding inlet 6 through the feeding surge bin upper valve 1a that opens, later closes feeding surge bin upper valve 1a, and feeding surge bin 3a forms the ordinary pressure airtight space. Meanwhile, the pressure in the other feeding buffer bin 3b is the same as the pressure in the furnace through the feeding buffer bin pressure relief hole 2b, nitrogen, water vapor or carbon dioxide is introduced through the inert gas blowing air inlet 5b at the lower part of the feeding buffer bin lower valve 4b, the atmosphere at the lower part of the feeding buffer bin lower valve 4b is a non-combustible gas, the feeding buffer bin lower valve 4b is opened, the material falls into the transition bin 7 under the action of gravity, the gas in the transition bin 7 enters the feeding buffer bin 3b, then the feeding buffer bin lower valve 4b is closed, the feeding buffer bin communication valve 19 is opened, the high-pressure gas in the feeding buffer bin 3b enters the feeding buffer bin 3a, the pressure of the two feeding buffer bins is the same, the feeding buffer bin communication valve 19 is closed at the moment, the feeding buffer bin 3b without the material is relieved through the feeding buffer bin pressure relief hole 2b, make feeding surge bin 3b become the ordinary pressure state, then open feeding surge bin upper valve 1b and feed, feeding surge bin 3a that has the material fills pressure release hole 2a through feeding surge bin and pressurizes, make pressure the same with stove internal pressure, inert gas through feeding surge bin lower valve 4a lower part sweeps air inlet 5a and lets in nitrogen gas, vapor or carbon dioxide, make feeding surge bin lower valve 4a lower part atmosphere be non-combustible gas, later open feeding surge bin lower valve 4a and make the material get into transition bin 7 under the action of gravity, two feeding surge bins work in turn, effectual improvement fills pressure release efficiency, the dirty gas of pressure release process exhaust has been reduced.

2) Gasification agent inlet gas

The gasification furnace body 22 mainly comprises a furnace top gasification agent inlet 8, a material distribution device 9, a sleeve 10, a gas outlet 11, a grate 13, a furnace bottom gasification agent inlet 14, a membrane water wall 12, a middle section gasification agent inlet 20 and a grate gasification agent distribution regulator 21. The top gasification agent air inlets 8 are arranged on the side edge of the transition bin 7, a plurality of top gasification agent air inlets are symmetrically arranged along the circumferential direction, and the top uniform air distribution is realized through a cavity formed in the transition bin region and the top gasification agent air inlets. The middle section gasification agent air inlet 20 is located above the sleeve 10 and horizontally arranged along the circumferential direction, and is used for regulating and controlling the position of the upper oxidation layer, so that the problem that the upper oxidation layer is too high or too low is avoided. The bottom gasifying agent inlet 14 is communicated with the bottom grate 13, and the bottom is uniformly distributed through the air distribution holes on the grate 13. The grate gasifying agent distribution regulator 21 is positioned in the cavity inside the grate 13, when the gasified raw material is low in heat value or the fixed carbon content is low, the demand of the gasifying agent supply quantity of the furnace bottom gasifying agent inlet 14 is less, and the small-flow uniform gas distribution is realized by reducing and regulating the height of the grate gasifying agent distribution regulator 21. The uniform air distribution of the furnace top gasifying agent air inlet 8 and the furnace bottom gasifying agent air inlet 14 can ensure that materials form a uniform and stable reaction layer in the gasification reaction zone, and the phenomenon of uneven reaction is avoided. The gasifying agents introduced into the gasifying agent inlets 8 and 14 are air and water vapor. The distributing device 9 is positioned at the upper part of the gasification furnace body right below the transition bin 7, and the materials falling into the furnace from the transition bin 7 are uniformly distributed in the furnace through the distributing device 9. The outer layer of the furnace body is a membrane type water-cooled wall 12, so that high temperature in the furnace is prevented from radiating to the outside, the slag bonding phenomenon of the inner wall of the furnace is also avoided, and the bulge problem can be effectively avoided compared with the traditional mode of adopting a water jacket.

3) Gasification process

The reaction zone in the furnace can be divided into a drying layer, a dry distillation layer, an upper oxidation layer, a reduction layer, a lower oxidation layer and an ash layer from top to bottom. The drying layer and the dry distillation layer are positioned above the sleeve in the furnace, the sleeve is arranged in the area between the lower part of the upper oxidation layer and the middle-upper part of the reduction layer, and the lower oxidation layer and the ash layer are positioned below the sleeve. The distributing device 9 realizes the even cloth of material in the drying layer, and the drying layer temperature is in 20 ~ 200 ℃ within range, and the moisture in the material is heated the evaporation and enters into the gaseous phase, and the material through drying gets into the layer of volatilizing and releases the volatile, generates tar and semicoke, and the temperature on dry distillation layer is in 200 ~ 600 ℃ within range. The tar and the semicoke enter the upper oxidation layer, the tar and the semicoke are subjected to oxidation reaction with oxygen in the gasifying agent to release heat, so that the temperature of the upper oxidation layer can reach 600-1200 ℃, meanwhile, part of the tar is cracked in a high-temperature region, the semicoke is only subjected to partial oxidation reaction due to insufficient gas-solid contact, the semicoke enters the reduction layer under the action of gravity of a material mainly comprising the semicoke, and carbon dioxide and water generated by oxidation of the upper oxidation layer and the semicoke in the reduction layer are subjected to gasification reaction, so that the gas production quality is improved. The semi-coke which is not reacted in the reduction layer enters the lower oxidation layer and is further oxidized by the gasification agent introduced into the gasification agent inlet 14 at the bottom of the furnace to release heat. The heat of the reduction layer comes from the heat radiation of the upper oxidation layer and the lower oxidation layer, the temperature range is 600-900 ℃, and the temperature range of the lower oxidation layer is 600-1100 ℃. The semicoke is changed into lime-ash and gets into the ash layer above the grate 13 after the oxide layer takes place complete oxidation reaction under, and the ash layer temperature range is within 200 ~ 600 ℃, and the grate 13 passes through the motor drive rotation, has scraper 25 on the grate 13 can realize the breakage of lime-ash, avoids massive lime-ash to block up. The gasification agent introduced into the furnace bottom gasification agent inlet 14 enters the ash layer through the grate cloth gas port to exchange heat with ash so as to realize the heating of the gasification agent and the cooling of the ash.

4) Slag discharge

The slag bin 16 of furnace body below is for discharging the ash in turn, slag bin lower valve 17 is closed state, slag bin upper valve 15 is open state, the lime-ash gets into slag bin 16 through the row cinder notch of side through rotatory extrusion after being broken by the grate, later close slag bin upper valve 15, fill pressure release through slag bin pressure release mouth 18 and release pressure, slag bin 16 pressure becomes the ordinary pressure state, open slag bin lower valve 17, discharge the lime-ash, later close slag bin lower valve 17, fill pressure through slag bin pressure release mouth 18 and carry out the pressure, slag bin 16 pressure is the same with in the stove, later open slag bin upper valve 15 and make the lime-ash on ash layer get into slag bin 16 and begin the new round of row of sediment.

5) Air outlet

The sleeve 10 is made of heat-resistant steel, the sleeve 10 and the furnace body form an interlayer, an annular cavity 24 can be formed in the area after the filling materials start to react, and the gas outlet 11 is horizontally arranged in the annular cavity area, so that uniform gas outlet can be effectively realized. The material below the interlayer cavity plays a role in filtering, and particulate matters in the fuel gas are reduced. Meanwhile, the annular cavity is radiated by the upper oxidation layer and the reduction layer to have higher temperature, and the gas carrying tar passes through the upper oxidation layer, the reduction layer and the outer interlayer cavity of the sleeve 10 within the range of 200-800 ℃, so that the tar can be fully cracked and gasified at high temperature, and finally the combustible gas with low tar, low particulate matters and high calorific value is obtained from the gas outlet 11.

The inner diameter of the furnace bottom of the gasification furnace is 3.2m, the processed materials are biomass, and the processing amount is 4000 Kg/h. The main operating conditions and gasification results were as follows:

(1) industrial analysis of materials is shown in the following Table

	Mt(％)	Mad(％)	Aad(％)	Vad(％)	Qnet,ar(MJ/kg)
						Biomass	5.00	3.16	2.59	75.59	18.25

(2) The operating conditions are as follows:

gasification pressure: 100KPa

Gasifying agent: air + water vapor

Air quantity: 6100Nm³/h

Amount of water vapor: 1000Kg/h

(3) And (3) gasification result:

gas production: 9600Nm³/h

The fuel gas comprises the following components: h₂：15.88％，CO：18.65％，CH₄：3.17％，CO₂：10.84％，N₂：50.61％，O₂：0.40％，C_nH_m：0.45％。

Gasification efficiency: 73 percent

Carbon content of ash: 3.1 percent of

The tar content of the fuel gas is as follows:<1g/Nm³

in the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art without departing from the scope of the present invention.

Claims (10)

1. A sleeve type double oxidation layer fixed bed gasification furnace is characterized by comprising:

a feeding device;

the reaction zone furnace body is arranged below the feeding device and comprises a furnace wall and a furnace chamber, the upper section of the furnace chamber is provided with a material distribution device, the middle section of the furnace chamber is provided with a sleeve, the bottom of the furnace chamber is provided with a grate, an annular cavity is formed between the sleeve and the furnace wall, the upper part of the sleeve is of a structure with a wide upper part and a narrow lower part, and the upper end of the sleeve is abutted against the furnace wall;

a furnace top gasification agent inlet, wherein the furnace top gasification agent inlet is arranged at the upper part and/or the top part of the furnace wall and extends into the furnace cavity;

the middle-section gasification agent inlet is arranged in the middle of the furnace wall and is higher than the area where the sleeve is arranged, and the middle-section gasification agent inlet extends into the furnace cavity;

the furnace bottom gasification agent inlet is arranged at the lower part of the furnace wall and is positioned below the grate, and the furnace bottom gasification agent inlet extends into the furnace cavity and is communicated with the lower part of the grate;

the gas outlet is arranged in the middle of the furnace wall and is positioned in the area where the annular cavity is positioned;

the gasification agent distribution regulator is arranged at the outlet end of the furnace bottom gasification agent air inlet in a manner of moving up and down and is positioned in the grate;

and the slag discharging device is arranged below or laterally below the reaction zone furnace body.

2. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 1, wherein at least one of the following conditions is satisfied:

the furnace top gasification device comprises a plurality of furnace top gasification agent air inlets which are uniformly arranged on the upper part of the furnace wall and/or the top of the furnace wall;

the gasification furnace comprises a plurality of middle-section gasification agent air inlets which are uniformly and horizontally arranged along the circumferential direction of the furnace wall;

the furnace comprises a plurality of gas outlets which are uniformly and horizontally arranged along the circumferential direction of the furnace wall.

3. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 1, wherein at least one of the following conditions is satisfied:

the feeding device comprises at least one feeding channel, each feeding channel is sequentially provided with a feeding hole, an upper valve of a feeding buffer bin, a lower valve of the feeding buffer bin and an inert gas purging air inlet from top to bottom, and a charging and pressure releasing port of the feeding buffer bin is formed in the side part of the feeding buffer bin;

the top of the furnace wall is connected with the feeding device through a transition bin, the transition bin is communicated with the furnace chamber, and a furnace top gasification agent air inlet is arranged on the side wall of the transition bin;

and the outer side of the furnace wall is a membrane water-cooled wall or a jacket water-cooled wall.

4. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 3, wherein at least one of the following conditions is satisfied:

the feeding device comprises two feeding channels, and a communicating valve is arranged between feeding buffer bins of the two feeding channels;

and the discharge end of the feeding channel is communicated with the transition bin and is positioned above the furnace top gasifying agent air inlet.

5. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 3, wherein the ratio of the height of the upper end of the sleeve from the lower valve of the feeding surge bin to the total height of the furnace body of the reaction zone is (0.4-0.8): 1, the ratio of the height of the lower end of the sleeve from the top of the grate to the total height of the furnace body in the reaction zone is (0.2-0.6): 1, the ratio of the height of the sleeve to the inner diameter of the reaction zone furnace body is (0.2-0.6): 1;

the ratio (0.1-0.3) of the maximum thickness of the annular cavity to the inner diameter of the reaction zone furnace body is as follows: 1;

the inner diameter of the reaction zone furnace body is 0.3-8 m;

the membrane water-cooled wall is in a tube array type or a coil type.

6. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 1, wherein at least one of the following conditions is satisfied:

the fire grate can be arranged in a rotating way, and a cloth air port is formed on the fire grate.

7. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 1, wherein the lower portion of the furnace wall has an inverted cone structure, a scraper for crushing ash is provided at a region of the furnace wall corresponding to the grate, a slag outlet is formed at the bottom of the inverted cone structure, and the slag outlet is connected to the slag discharging device.

8. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 1, wherein the grate is provided with a scraper for crushing ash, and a slag outlet is formed on a side wall of a lower portion of the furnace wall, and the slag outlet is connected to the slag discharging device.

9. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 1, wherein the slag discharging device comprises an upper slag bin valve, a lower slag bin valve and a slag bin upper valve, and a slag bin pressure charging and discharging port is arranged on the side of the slag bin.

10. The telescopic dual oxidation layer fixed bed gasification furnace according to claim 1, wherein a pressure measuring device and/or a temperature measuring device is provided on the reaction zone furnace body, the pressure measuring device is used for detecting the pressure in the reaction zone furnace body, and the temperature measuring device is used for detecting the temperature in the reaction zone furnace body.

Images