Semi-gasification combustion device and method

Abstract

The invention discloses a semi-gasification combustion device and method. A fire grate is arranged in the semi-gasification combustion device and divides the inner space of the semi-gasification combustion device into an upper area and a lower area. Wherein a primary combustion chamber and a secondary combustion chamber are sequentially arranged in an area above the fire grate; the area below the fire grate is respectively connected with a primary air main pipeline and a tertiary air main pipeline; a feeding port is further formed between the fire grate and the primary combustion chamber, a feeding port tertiary air flat pipeline is arranged close to the feeding port, and the feeding port tertiary air flat pipeline is connected with the tertiary air main pipeline through a feeding port tertiary air conveying pipeline. And the bottom of the secondary combustion chamber is connected with a secondary air main pipeline. According to the device and method, high-temperature, high-humidity and low-oxygen-content flue gas is reasonably used as a gasifying agent, the gasification ratio is increased, meanwhile, tail exhaust flue gas is recycled, and the combustion efficiency is improved while energy is saved.

Description

Technical Field

[0001] The present application relates to a semi-gasification combustion device and method using biomass as fuel. Background Art

[0002] Biomass fuel is solar energy fixed by plant photosynthesis, which has the advantages of being renewable, zero CO2 emissions, and low SO2 emissions. According to the "3060 Zero Carbon Biomass Energy Development Potential Blue Book", my country's annual biomass resource output is 3.494 billion tons, and the development potential for energy utilization is 460 million tons of standard coal. It is estimated that by 2030, the use of biomass energy will reduce carbon emissions by more than 900 million tons for the whole society, and by 2060, carbon emissions will be reduced by more than 2 billion tons. However, the existing biomass direct combustion technology has problems such as low combustion efficiency and excessive nitrogen oxide emissions.

[0003] In the gypsum board industry, biomass fuel is only mixed with coal in the form of machine-made pellets (mixing rate is less than 30%), and the enhanced combustion in the fluidized bed furnace causes the extremely small ash to enter the heat exchange equipment with the flue gas, causing coking and blockage. Therefore, it is urgent to develop 100% biomass fuel efficient application technology suitable for the gypsum board production field. Summary of the invention

[0004] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of protection of this application.

[0005] This application combines the combustion mechanism of biomass fuel and provides a biomass semi-gasification combustion device with a combustion mode between "gasification combustion" and "direct combustion", and particularly cites the characteristics of primary air, secondary air, and tertiary air. The primary air is used to provide 40% of the air volume required for complete combustion of biomass fuel, the secondary air is used to provide 60% of the air volume required for complete combustion of biomass fuel, and the tertiary air uses the high-temperature (temperature 90-100°C) and high-humidity (35-40%) flue gas with an oxygen content of 8%-10% on the exhaust side of the calcination process as a gasification agent, which improves the gasification ratio while recycling the tail exhaust gas, saving energy while improving combustion efficiency.

[0006] The first aspect of the present application provides a semi-gasification combustion device, wherein a grate is arranged inside the semi-gasification combustion device, and the grate divides the internal space of the semi-gasification combustion device into two upper and lower areas; wherein: The area above the grate is a primary combustion chamber and a secondary combustion chamber from the grate upwards; the area below the grate is connected to the primary air main duct and the tertiary air main duct respectively; the bottom of the secondary combustion chamber is connected to the secondary air main duct; A feed port is arranged between the grate and the primary combustion chamber, a feed port tertiary air flat duct is arranged next to the feed port, and the feed port tertiary air flat duct and the tertiary air main duct are connected via a feed port tertiary air delivery duct.

[0007] In an exemplary embodiment, the grate is an inclined reciprocating grate, and optionally, the inclination angle of the grate is 15°.

[0008] In an exemplary embodiment, along the length direction of the inclined surface, the area below the grate can be divided into four areas, namely area A, area B, area C and area D. The grate in each area can be driven individually and the operating speed can be adjusted individually to adjust the combustion state according to different fuel types and moisture content.

[0009] In an exemplary embodiment, the A zone and the D zone each occupy 15-20% of the area of ​​the region below the grate, and the B zone and the C zone each occupy 35-40% of the area of ​​the region below the grate.

[0010] In an exemplary embodiment, along the length direction of the inclined surface, the area below the grate may be further divided into less than or more than four areas.

[0011] In an exemplary embodiment, the area B, the area C and the area D are respectively connected to the primary air main duct, the area A and the area B are respectively connected to the tertiary air main duct, each area corresponding to ABCD is independent of each other, and the air volume is adjustable.

[0012] In an exemplary embodiment, a tertiary air regulating valve and a primary air regulating valve may be respectively provided at the interfaces where the tertiary air main duct, the primary air main duct and the area A, the area B, the area C and the area D are connected.

[0013] In an exemplary embodiment, the tertiary air flat duct at the feed inlet is located above the feed inlet.

[0014] In an exemplary embodiment, a tertiary air regulating valve at the feed inlet is also provided in the tertiary air conveying pipeline at the feed inlet.

[0015] In an exemplary embodiment, secondary air nozzles are arranged around the bottom of the secondary combustion chamber, and the secondary air nozzles are connected to the secondary air main duct.

[0016] In an exemplary embodiment, the secondary air nozzle is tilted downward; optionally, the downward tilt angle of the secondary air nozzle is 15°.

[0017] In an exemplary embodiment, the secondary air nozzle is a high-speed reverse mixing transverse cross nozzle for improving gasification combustion efficiency.

[0018] In an exemplary embodiment, the primary combustion chamber is composed of side walls and front and rear arches. During the continuous combustion process, the side walls and the front and rear arches form a heat storage body, which forms a strong heat radiation effect on the fuel entering the furnace to increase the drying and gasification process. In order to enhance the efficiency of secondary combustion, the present application reduces the angle of the front and rear arches to reduce the space of the primary combustion chamber and increase the space of the secondary combustion chamber.

[0019] In an exemplary embodiment, the semi-gasification combustion device further comprises: A tertiary air temperature adjustment pipeline is connected to the bottom of the secondary combustion chamber. A primary air fan connected to the primary air main duct, for providing primary air; A secondary air fan connected to the secondary air main duct, for providing secondary air; a smoke exhaust fan connected to the tertiary air main duct and the tertiary air temperature adjustment duct, for providing tertiary air; and A feeding and conveying device is arranged outside the semi-gasification combustion device and connected to the feed port.

[0020] In an exemplary embodiment, a tertiary air temperature regulating nozzle is further provided at the bottom of the secondary combustion chamber, and the tertiary air temperature regulating pipe is connected to the tertiary air temperature regulating nozzle; optionally, the tertiary air temperature regulating nozzle is provided with a nozzle in the form of a spiral line.

[0021] In an exemplary embodiment, the feeding and conveying device includes a feeding device, a transport device, an intermediate buffer bin and a pusher. The feeding device, the transport device, the intermediate buffer bin and the feed port are connected in sequence. The pusher is connected to the intermediate buffer bin for pushing fuel into the feed port.

[0022] In an exemplary embodiment, the feeding device may be a double screw conveyor.

[0023] In an exemplary embodiment, the transport device may be a high-angle belt conveyor.

[0024] The second aspect of the present application provides a method for combustion using the above-mentioned semi-gasification combustion equipment, comprising the following steps: S1. The fuel is fed into the row surface of the grate; S2. After the fuel is ignited, the primary air is blown in through the primary air main duct from the air outlet under the grate; while the secondary air is blown in through the secondary air main duct from the bottom of the secondary combustion chamber for primary and secondary combustion; S3. When the fuel combustion reaches the required temperature, the tertiary air is blown into the tertiary air flat duct from the air supply port under the grate and the feed port through the tertiary air main duct to allow the fuel to be fully burned; wherein, the tertiary air is transported to area A, area B and the tertiary air flat duct at the feed port through the tertiary air main duct.

[0025] In an exemplary embodiment, the primary air provides 40% of the air volume required for complete combustion of the fuel, the secondary air provides 60% of the air volume required for complete combustion of the fuel, and the tertiary air is high-temperature and high-humidity flue gas with an oxygen content of 8%-10% on the exhaust side of the calcination process.

[0026] In an exemplary embodiment, the temperature of the tertiary air is 90-100° C., and the humidity is 35-40%.

[0027] In an exemplary embodiment, the volume content of carbon dioxide in the tertiary air is 11-13%.

[0028] In an exemplary embodiment, in step S1, the fuel may be biomass fuel.

[0029] In an exemplary embodiment, step S1 includes: the biomass fuel is sent to a high-angle belt conveyor by a double-screw conveyor and enters an intermediate buffer bin, a pusher adjusts the feeding time interval according to the heat load, and the biomass fuel is pushed into the grate surface in batches.

[0030] In an exemplary embodiment, in step S2, the primary air is only delivered to the B zone, the C zone and the D zone through the primary air main duct, and the fuel is partially burned in an organized manner under the given conditions of the primary air, generating chemical heat so that the other part of the fuel releases combustible volatile gases through thermal radiation; at the same time, the combustible volatile gases and the mixed flue gas produced by the primary combustion rise, mix with the secondary air, undergo secondary combustion and release all the heat.

[0031] In an exemplary embodiment, in step S2, secondary air is injected into the secondary combustion chamber through the secondary air main duct from the secondary air nozzles around the bottom of the secondary combustion chamber.

[0032] In an exemplary embodiment, in step S3, the tertiary air flat ducts in zone A and the feed inlet are respectively used to individually control the tertiary air volumes through the tertiary air regulating valve and the feed inlet tertiary air regulating valve.

[0033] In an exemplary embodiment, in step S3, the zone B controls the mixing and distribution ratio of the primary air and the tertiary air in the zone B through the primary air regulating valve and the tertiary air regulating valve according to the gasification reaction temperature; for example, when the gasification reaction temperature is insufficient, the primary air regulating valve can be appropriately opened and the tertiary air regulating valve can be closed, and vice versa.

[0034] In an exemplary embodiment, in step S3, the C zone and the D zone are mainly involved in the carbon burnout function, and the primary air volume provided is controlled by controlling the primary air regulating valve.

[0035] In an exemplary embodiment, step S3 further includes: tertiary air is blown into the bottom of the secondary combustion chamber through a tertiary air temperature adjustment pipe; Optionally, tertiary air is blown into the secondary combustion chamber in a spiral form through the tertiary air temperature adjustment pipe and the tertiary air temperature adjustment nozzle at the bottom of the secondary combustion chamber.

[0036] Compared with the prior art, this application has the following technical effects: 1) In this application, the primary air is used to provide 40% of the air volume required for complete combustion of biomass fuel, the secondary air is used to provide 60% of the air volume required for complete combustion of biomass fuel, and one function of the tertiary air is to be introduced as a gasifying agent to achieve high gasification ratio combustion, and another function is to adjust the combustion temperature in the secondary combustion chamber; wherein, in the semi-gasification combustion process of this application, the gasification ratio can reach more than 60%; 2) In this application, the area below the grate is divided into four areas, each of which is independent of each other and has adjustable air volume. The grates corresponding to the four areas are driven separately and the operating speed is adjustable separately. At the same time, the primary air and tertiary air are designed to be mixed and distributed in area B; 3) The design of the secondary air and secondary air nozzle in this application improves the gasification and combustion efficiency. The tertiary air is powered by the smoke exhaust fan and delivered to the required process parts through pipelines, and is used as a gasifying agent and a low-temperature medium for temperature control: the main function of the flat pipeline delivered to zones A and B and the feed port through pipelines is to be introduced as a gasifying agent; it is delivered to the middle and lower part of the secondary combustion chamber through pipelines, and air is delivered in the form of a spiral nozzle, which is mainly used for air distribution and temperature regulation. At the same time, the centrifugal force generated by the tangential spiral can make the unburned particles carried in the flue gas settle and fall; in addition, the tertiary air is delivered in a flat port distribution at the upper part of the feed port, which can prevent the fuel from flashing back and burning in the middle bin in front of the furnace, damaging the feeding equipment, and can also provide a gasifying agent on the fuel surface; 4) Due to the different furnace structures and operating principles of the semi-gasification device, the semi-gasification furnace does not have a clear boundary between the drying layer, oxidation layer, and reduction layer. Various reactions often occur in both directions. Even during the process of fuel entry, combustion flashback occurs under the conditions of sufficient primary air and furnace heat radiation, so that the flame spreads into the silo, causing production accidents. Therefore, controlling the temperature and oxygen content of zone A and the feed port becomes the key. In the operation of the semi-gasification furnace, it is impossible to use air as a gasifier to achieve a higher gasification ratio, because the sufficient oxygen content in the air will aggravate the direct combustion effect. The recovery process exhaust gas in the form of tertiary air as a gasifier can not only save energy and reduce emissions but also achieve a perfect match of working conditions. The oxygen content of the tertiary air is only 8%-10%, the carbon dioxide content is 11-13%, and the temperature of about 100°C carries a large amount of water vapor generated by the calcination section. These parameter conditions constitute the two gasifiers of carbon dioxide and water vapor. Among them, the reduction reaction of carbon dioxide as a gasifier and the reduction reaction of water vapor as a gasifier are as follows: , .

[0037] In addition to the carbon dioxide brought in by the tertiary air, the carbon dioxide produced by the combustion of charcoal and the combustion of oxygen from the primary air also participate in the above reactions. The above two reduction reactions are endothermic reactions. This part of the heat comes from the heat generated by the combustion of carbon and the direct combustion of some biomass fuels, the heat radiated by the furnace heat, etc. 5) The tertiary air in zone A and the feed port of this application can inhibit the premature combustion of fuel and the occurrence of flashback, prevent combustion in the middle bin in front of the furnace, and damage the feeding equipment; at the same time, the fuel can stay between 150-200℃ for a long time; when the fuel temperature reaches above 150℃, the biomass begins to pyrolyze, and as the temperature rises, volatiles are continuously precipitated to generate charcoal, and combustible gases such as H2, CO, CO2, and CH4 are released. This process is accompanied by a small-scale combustion phenomenon on the surface of the material, but it can inhibit large-scale rapid combustion. Therefore, the tertiary air flat pipes in zone A and the feed port are set to fully enter the tertiary air and control the tertiary air volume separately through valves; zone B is equipped with a primary air regulating valve and a tertiary air regulating valve according to the working conditions. When the gasification reaction temperature is insufficient, the primary air regulating valve can be appropriately adjusted to open and close the tertiary air regulating valve, and vice versa; zones C and D are mainly involved in the carbon burnout function, and the primary air volume provided is controlled by controlling the primary air regulating valve.

[0038] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by implementing the present application. Other advantages of the present application can be realized and obtained by the schemes described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are used to provide an understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0040] Figure 1 This is a schematic diagram of the structure of the semi-gasification device of this application.

[0041] Illustration Description: 1-grate, 2-primary combustion chamber, 3-secondary air nozzle, 4-secondary air main duct, 5-tertiary air temperature control duct, 6-tertiary air temperature control nozzle, 7-secondary combustion chamber, 8-intermediate buffer bin, 9-tertiary air flat duct at feed inlet, 10-pusher, 11-tertiary air conveying duct at feed inlet, 12-tertiary air regulating valve at feed inlet, 13-tertiary air main duct, 14-tertiary air regulating valve, 15-primary air regulating valve, 16-primary air main duct. DETAILED DESCRIPTION

[0042] The present application describes multiple embodiments, but the description is exemplary rather than restrictive, and it is obvious to those skilled in the art that there may be more embodiments and implementations within the scope of the embodiments described in the present application. Although many possible feature combinations are shown in the drawings and discussed in the specific embodiments, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with any other feature or element in any other embodiment, or may replace any other feature or element in any other embodiment.

[0043] The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in the present application may also be combined with any conventional features or elements to form a unique invention scheme. Any features or elements of any embodiment may also be combined with features or elements from other invention schemes to form another unique invention scheme. Therefore, it should be understood that any feature shown and / or discussed in the present application may be implemented individually or in any appropriate combination. Therefore, except for the limitations made according to the attached claims and their equivalents, the embodiments are not subject to other restrictions. In addition, various modifications and changes may be made within the scope of protection of the attached claims.

[0044] In addition, when describing representative embodiments, the specification may have presented the method and / or process as a specific sequence of steps. However, to the extent that the method or process does not rely on the specific order of the steps described herein, the method or process should not be limited to the steps of the specific order described. As will be understood by those of ordinary skill in the art, other sequences of steps are also possible. Therefore, the specific sequence of the steps set forth in the specification should not be interpreted as a limitation to the claims. In addition, the claims for the method and / or process should not be limited to the steps of performing them in the order written, and those skilled in the art can easily understand that these sequences can be changed and still remain within the spirit and scope of the embodiments of the present application.

[0045] Example 1. like Figure 1 As shown, a semi-gasification combustion device is provided with a grate 1 inside the semi-gasification combustion device, and the grate 1 divides the internal space of the semi-gasification combustion device into two upper and lower areas; wherein the area above the grate 1 is a primary combustion chamber 2 and a secondary combustion chamber 7 in sequence from the grate upward; the area below the grate 1 is connected to the primary air main duct 16 and the tertiary air main duct 13 respectively; the bottom of the secondary combustion chamber 7 is connected to the secondary air main duct 4; A feed port (not shown) is also provided between the grate 1 and the primary combustion chamber, a feed port tertiary air flat duct 9 is provided next to the feed port, and the feed port tertiary air flat duct 9 and the tertiary air main duct 13 are connected via a feed port tertiary air delivery duct 11.

[0046] like Figure 1 As shown, the grate 1 is an inclined reciprocating grate, and the inclination angle of the grate 1 is 15°; along the length direction of the inclined surface, the area below the grate 1 can be divided into four areas, which are area A, area B, area C and area D respectively; wherein, the area A and the area D each occupy 15-20% of the area below the grate 1, and the area B and the area C each occupy 35-40% of the area below the grate 1; The B zone, the C zone and the D zone are respectively connected to the primary air main duct 16, and the A zone and the B zone are respectively connected to the tertiary air main duct 13; wherein, a tertiary air regulating valve 14 and a primary air regulating valve 15 may be respectively provided at the interfaces where the tertiary air main duct 13, the primary air main duct 16 are connected with the A zone, the B zone, the C zone and the D zone.

[0047] The feed inlet tertiary air flat duct 9 is located above the feed inlet, and a feed inlet tertiary air regulating valve 12 is also provided in the feed inlet tertiary air conveying duct 11.

[0048] The secondary air nozzles 3 are arranged around the bottom of the secondary combustion chamber 7, and the secondary air nozzles 3 are connected to the secondary air main duct 4; Figure 1 As shown, the secondary air nozzle 3 is tilted downward at an angle of 15°; the secondary air nozzle 3 is a high-speed reverse mixing transverse cross nozzle for improving gasification combustion efficiency.

[0049] The semi-gasification combustion device also includes a tertiary air temperature control pipe 5, which is connected to the bottom of the secondary combustion chamber 7: a tertiary air temperature control nozzle 6 is arranged at the bottom of the secondary combustion chamber 7, and the tertiary air temperature control pipe 5 is connected to the tertiary air temperature control nozzle 6; the tertiary air temperature control nozzle 6 is provided with a nozzle in the form of a spiral line.

[0050] The primary combustion chamber 2 is composed of side walls and front and rear arches (not shown): during the continuous combustion process, the side walls and the front and rear arches form a heat storage body, which exerts a strong thermal radiation effect on the fuel entering the furnace to increase the drying and gasification process; in the present application, in order to enhance the secondary combustion efficiency, the angle of the front and rear arches can be lowered to reduce the space of the primary combustion chamber 2 and increase the space of the secondary combustion chamber 7.

[0051] The semi-gasification combustion device further comprises: a primary fan connected to the primary air main duct 16, a secondary fan connected to the secondary air main duct 4, a smoke exhaust fan connected to the tertiary air main duct 13 and the tertiary air temperature adjustment duct 5, and a feeding and conveying device arranged outside the semi-gasification combustion device and connected to the feed port; The feeding and conveying device includes a feeding device, a transportation device, an intermediate buffer bin 8 and a pusher 10. The feeding device, the transportation device, the intermediate buffer bin 8 and the feed port are connected in sequence. The pusher 10 is connected to the intermediate buffer bin 8 for pushing the fuel into the feed port. In this embodiment, the feeding device is a double-screw conveyor, and the transportation device is a large-angle belt conveyor.

[0052] Example 2. In this embodiment, along the length direction of the inclined surface, the area below the grate 1 can also be divided into less than or more than four areas.

[0053] Example 3. A method for combustion using the semi-gasification combustion device in Example 1 comprises the following steps: S1. The fuel is fed into the row surface of the grate 1; In this step, the fuel may be biomass fuel. Specifically, the biomass fuel is delivered to the high-angle belt conveyor by the double screw conveyor and enters the intermediate buffer bin 8. The pusher 10 adjusts the feeding time interval according to the heat load, and the biomass fuel is pushed into the row surface of the grate 1 in batches. S2. After the fuel is ignited, primary air is blown into the air supply port under the grate 1 through the primary air main duct 16; wherein the primary air is only sent to the B zone, the C zone and the D zone through the primary air main duct 16, and the fuel is partially burned in an organized manner under the given conditions of the primary air, generating chemical heat so that another part of the biomass fuel releases combustible volatile gas through thermal radiation; At the same time, secondary air is blown into the bottom of the secondary combustion chamber 7 through the secondary air main duct 4 for primary combustion and secondary combustion; wherein the combustible volatile gas and the mixed flue gas produced by the primary combustion rise, mix with the secondary air, and undergo secondary combustion, releasing all the heat; In this step, the primary air provides 40% of the air volume required for complete combustion of the fuel, and the secondary air provides 60% of the air volume required for complete combustion of the fuel; the secondary air is injected into the secondary air nozzles 3 around the bottom of the secondary combustion chamber 7 through the secondary air main duct 4; S3. When the fuel combustion reaches the required temperature, the tertiary air is blown into the air supply port under the grate 1 and the tertiary air flat pipe 9 at the feed port through the tertiary air main pipe 13 to fully burn the fuel; wherein the tertiary air is respectively transported to the A zone, the B zone and the tertiary air flat pipe 9 at the feed port through the tertiary air main pipe 13 and the tertiary air delivery pipe 11 at the feed port; In this step, the tertiary air is high-temperature and high-humidity flue gas with an oxygen content of 8%-10% on the exhaust side of the calcination process. The temperature of the tertiary air is 90-100°C, the humidity is 35-40%, and the carbon dioxide content is 11-13%; The tertiary air volume of the zone A and the feed inlet tertiary air flat duct 9 is controlled separately through the tertiary air regulating valve 14 and the feed inlet tertiary air regulating valve 12; The zone B can be provided with a primary air regulating valve 15 and a tertiary air regulating valve 14 according to the working conditions. When the gasification reaction temperature is insufficient, the primary air regulating valve 15 can be appropriately opened and the tertiary air regulating valve 14 can be closed, and vice versa. The C zone and the D zone are mainly involved in the carbon burnout function, and the primary air volume provided is controlled by controlling the primary air regulating valve 15 .

[0054] Example 4. In the method of Example 3, step S3 also includes: tertiary air is blown into the bottom of the secondary combustion chamber 7 through the tertiary air temperature control pipe 5; specifically: the tertiary air is blown into the bottom of the secondary combustion chamber 7 through the tertiary air temperature control pipe 5 from the tertiary air temperature control nozzle 6 at the bottom of the secondary combustion chamber 7 in the form of a spiral line, thereby achieving the air distribution and temperature control effect. At the same time, the centrifugal force generated by the tangential spiral can cause the unburned particles carried in the flue gas to settle and fall.

[0055] Comparative Example 1. The semi-gasification combustion device in patent CN117823887A.

[0056] Compared with the semi-gasification device in patent CN117823887A, the semi-gasification combustion device of the present application has the following technical effects: 1) The device of the present application is provided with a tertiary air flat duct at the feed inlet and a tertiary air delivery duct at the feed inlet, so that the tertiary air entering the A zone and the B zone can also suppress the backfire function. No backfire occurs in the device of the present application. At the same time, the furnace temperature corresponding to the grate in the A zone is reduced by 300°C; 2) The gasification ratio of the device of the present application is increased by 10-15%, and the secondary combustion burner temperature is more than 200°C higher than the furnace temperature of the primary combustion chamber.

[0057] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0058] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include at least one of the features.

[0059] In the description of the present application, “plurality” means at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0060] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be a connection between two elements or an interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0061] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0062] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0063] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A semi-gasification combustion device, characterized in that: The semi-gasification combustion device is provided with a grate inside, and the grate divides the internal space of the semi-gasification combustion device into two upper and lower areas; wherein: The area above the grate is a primary combustion chamber and a secondary combustion chamber from the grate upwards; the area below the grate is connected to the primary air main duct and the tertiary air main duct respectively; the bottom of the secondary combustion chamber is connected to the secondary air main duct; A feed port is arranged between the grate and the primary combustion chamber, a feed port tertiary air flat duct is arranged next to the feed port, and the feed port tertiary air flat duct and the tertiary air main duct are connected via a feed port tertiary air delivery duct.

2. The semi-gasification combustion device according to claim 1, characterized in that: The grate is an inclined reciprocating grate; along the length direction of the inclined surface, the area below the grate is divided into four areas, namely area A, area B, area C and area D; Optionally, the inclination angle of the grate is 15°; Optionally, the A zone and the D zone each occupy 15-20% of the area of ​​the region below the grate; Optionally, the zone B and the zone C each occupy 35-40% of the area of ​​the region below the grate.

3. The semi-gasification combustion device according to claim 2, characterized in that: The B zone, the C zone and the D zone are respectively connected to the primary air main duct, and the A zone and the B zone are respectively connected to the tertiary air main duct; Optionally, a tertiary air regulating valve and a primary air regulating valve are respectively provided at the interfaces where the tertiary air main duct, the primary air main duct and the area A, the area B, the area C and the area D are connected.

4. The semi-gasification combustion device according to any one of claims 2 to 3, characterized in that: The tertiary air flat duct of the feed inlet is located above the feed inlet; Optionally, a tertiary air regulating valve at the feed inlet is also provided in the tertiary air conveying pipeline at the feed inlet.

5. The semi-gasification combustion device according to any one of claims 2 to 3, characterized in that: Secondary air nozzles are arranged around the bottom of the secondary combustion chamber, and the secondary air nozzles are connected to the secondary air main duct; Optionally, the secondary air nozzle is arranged to be tilted downward; Optionally, the secondary air nozzle is tilted downward at an angle of 15°; Optionally, the secondary air nozzle is a high-speed reverse mixing transverse cross nozzle.

6. The semi-gasification combustion device according to any one of claims 2 to 3, characterized in that: The primary combustion chamber is composed of side walls and front and rear arches.

7. The semi-gasification combustion device according to any one of claims 2 to 3, characterized in that: The semi-gasification combustion device also includes: A tertiary air temperature adjustment pipeline is connected to the bottom of the secondary combustion chamber. A primary air fan connected to the primary air main duct, for providing primary air; A secondary air fan connected to the secondary air main duct, for providing secondary air; a smoke exhaust fan connected to the tertiary air main duct and the tertiary air temperature adjustment duct, for providing tertiary air; and A feeding and conveying device is arranged outside the semi-gasification combustion device and connected to the feed port.

8. The semi-gasification combustion device according to claim 7, characterized in that: A tertiary air temperature adjustment nozzle is also provided at the bottom of the secondary combustion chamber, and the tertiary air temperature adjustment pipeline is connected to the tertiary air temperature adjustment nozzle; Optionally, the tertiary air temperature adjustment nozzle is provided with a nozzle in the form of a spiral line.

9. The semi-gasification combustion device according to claim 7, characterized in that: The feeding and conveying device comprises a feeding device, a transport device, an intermediate buffer bin and a pusher, wherein the feeding device, the transport device, the intermediate buffer bin and the feed port are connected in sequence, and the pusher is connected to the intermediate buffer bin; Optionally, the feeding device is a double screw conveyor; Optionally, the transport device is a high-angle belt conveyor.

10. A method for combustion in a semi-gasification combustion device according to any one of claims 2 to 9, characterized in that: The following steps are involved: S1. Feed the fuel into the grate surface; S2. After the fuel is ignited, the primary air is blown in through the primary air main duct from the air outlet under the grate; while the secondary air is blown in through the secondary air main duct from the bottom of the secondary combustion chamber for primary and secondary combustion; S3. When the fuel combustion reaches the required temperature, the tertiary air is blown into the tertiary air flat pipes from the air supply port and the feed port under the grate through the tertiary air main pipe to make the fuel fully burn.

11. The method according to claim 10, characterized in that The primary air provides 40% of the air volume required for complete combustion of the fuel, the secondary air provides 60% of the air volume required for complete combustion of the fuel, and the tertiary air is high-temperature and high-humidity flue gas with an oxygen content of 8%-10% on the exhaust side of the calcination process; Optionally, the temperature of the tertiary air is 90-100°C; Optionally, the humidity of the tertiary air is 35-40%; Optionally, the volume content of carbon dioxide in the tertiary air is 11-13%.

12. The method according to claim 10 or 11, characterized in that: In step S1, the fuel is biomass fuel; Optionally, step S1 includes: the fuel is delivered to the high-angle belt conveyor by a double-screw conveyor and enters the intermediate buffer bin, the pusher adjusts the feeding time interval according to the heat load condition, and the fuel is pushed into the grate surface in batches.

13. The method according to claim 10 or 11, characterized in that: In step S2, secondary air is injected into the secondary combustion chamber through the secondary air main duct from the secondary air nozzles around the bottom of the secondary combustion chamber; and / or In step S3, the tertiary air flat ducts in zone A and the feed port respectively control the tertiary air volumes through the tertiary air regulating valve and the feed port tertiary air regulating valve; the zone B controls the mixing and distribution ratio of the primary air and the tertiary air in zone B through the primary air regulating valve and the tertiary air regulating valve according to the gasification reaction temperature; the zone C and the zone D control the primary air volume provided by controlling the primary air regulating valve.

14. The method according to claim 10 or 11, characterized in that: Step S3 also includes: tertiary air is blown into the bottom of the secondary combustion chamber through a tertiary air temperature adjustment pipe; Optionally, tertiary air is blown into the secondary combustion chamber in a spiral form through the tertiary air temperature adjustment pipe and the tertiary air temperature adjustment nozzle at the bottom of the secondary combustion chamber.

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