A carbon-containing waste gasifier and a gasification method for carbon-containing waste

Abstract

The present invention provides a carbon-containing waste gasifier and a gasification method for carbon-containing waste. With this gasifier, combustible waste gas and combustible carbon-containing waste can be integrated in one gasifier. Using this gasifier, it is convenient to utilize the combustible waste gas to provide high energy and promote the gasification of combustible carbon-containing waste to produce syngas. The gasifier includes a gasification chamber and a quench chamber. A slag discharge port is provided at the bottom of the gasification chamber, and a downcomer is provided directly below the slag discharge port. A burner is installed at the top of the gasification chamber. The burner includes a central annular channel for inputting combustible waste gas, a first annular channel for inputting an oxidant, a second annular channel for inputting combustible carbon-containing waste, and a third annular channel for inputting an oxidant, which are sequentially sleeved from the inside to the outside; there is a combustion space for the reaction of combustible waste gas and oxidant between the outlet at the bottom of the central annular channel and the outlet at the bottom of the first annular channel; a purging device is installed between the slag discharge port and the downcomer, and a purging port is provided on the purging device.

Description

Technical Field

[0001] The present invention relates to the treatment and utilization technology of carbon-containing waste, and particularly relates to a carbon-containing waste gasifier and a gasification method for carbon-containing waste. Background Art

[0002] Solid carbon-containing wastes such as sludge and livestock and poultry wastes are biomass resources with large reserves, wide distribution, renewable, and low S, N and ash contents. The emissions of sulfur and nitrogen oxides and dust after combustion are much smaller than those of fossil fuels, which is relatively friendly to the environment. However, due to the low mass and energy density of carbon-containing wastes and high moisture content, they are not easy to store and transport. If directly used as fuel, the combustion thermal efficiency is low and it seriously pollutes the environment. At present, pyrolysis or gasification processes are proposed industrially to convert carbon-containing wastes into liquid or gas raw materials with higher energy density for use. Currently, mainstream biomass gasification processes in the world all require pretreatment. One is to compact biomass under high pressure into particles with high quality and energy density, and the other is hydrothermal treatment to remove excess moisture. The pretreatment process is complex, consumes more energy, causes unnecessary waste, and has a high cost.

[0003] Gas combustible wastes such as the excess coke oven gas and hydrogen generated by most chemical plants currently will be directly burned and discharged through the waste gas torch if they cannot be further utilized, resulting in serious energy waste. Summary of the Invention

[0004] The present invention provides a gasifier, which can integrate combustible waste gas and combustible carbon-containing waste (such as solid carbon-containing waste or slurry containing solid carbon-containing waste) in one gasifier. Using this gasifier, it is convenient to use combustible waste gas to provide high energy, promote the gasification of combustible carbon-containing waste, thereby generating syngas, and this syngas can be used for the synthesis of downstream chemical products, etc.

[0005] To achieve its purpose, the present invention provides the following technical solutions:

[0006] The present invention provides a carbon-containing waste gasifier, which includes a gasification chamber and a quench chamber provided below the gasification chamber. A slag discharge port is provided at the bottom of the gasification chamber, and a downcomer vertically extending into the inner cavity of the quench chamber is provided directly below the slag discharge port. A burner is installed at the top of the gasification chamber.

[0007] The burner includes a central annular channel for inputting combustible waste gas, a first annular channel for inputting oxidant, a second annular channel for inputting combustible carbon-containing waste, and a third annular channel for inputting oxidant, which are sequentially sleeved from the inside to the outside. Entrances are provided at the tops of the respective channels, and exits are provided at the bottoms.

[0008] A combustion space for the reaction of combustible waste gas and oxidant is left between the outlet at the bottom of the central annular channel and the outlet at the bottom of the first annular channel;

[0009] A purging device is installed between the slag discharge opening and the downcomer. The purging device is provided with purging openings for jetting steam or carbon dioxide onto the molten slag falling through the slag discharge opening. There are multiple purging openings, and each purging opening is evenly spaced.

[0010] In some embodiments, the wall thickness of the central annular channel is thinned at the outlet at its bottom, and the wall thickness of the outlet end face of the central annular channel is 0.4 mm - 0.6 mm.

[0011] In some embodiments, the purging openings are arranged such that the jetting direction of the steam or carbon dioxide is inclined downward, and the included angle between the jetting direction and the central axis of the gasifier is 30 - 45 degrees.

[0012] In some embodiments, the purging device includes an annular purging pipeline and a gas supply pipeline connected to the annular purging pipeline. The gas supply pipeline is connected to a steam gas source or a carbon dioxide gas source;

[0013] Multiple purging openings are provided on the annular purging pipeline.

[0014] In some embodiments, the annular purging pipeline is a circular coiled pipe, and the purging openings located on the same circumference are evenly spaced.

[0015] In some embodiments, the outlet direction at the bottom of the first annular channel is the vertical direction; the outlet directions at the bottoms of the second annular channel and the third annular channel are both inclined downward towards the central axis of the burner and form an included angle of 50 - 60 degrees with the central axis of the burner.

[0016] In some embodiments, the combustible carbon-containing waste conveyed by the second annular channel is solid combustible carbon-containing waste or combustible carbon-containing waste slurry.

[0017] The present invention also provides a method for gasifying carbon-containing waste. The gasification method uses the carbon-containing waste gasifier described above to gasify the carbon-containing waste;

[0018] Wherein, the carbon-containing waste includes solid combustible carbon-containing waste, preferably also includes liquid carbon-containing waste, and further preferably also includes gaseous combustible carbon-containing waste.

[0019] In some embodiments, during the gasification process, the combustible waste gas is conveyed through the central annular channel, and the combustible waste gas is the gaseous combustible carbon-containing waste or non-carbon-containing combustible waste gas;

[0020] During the gasification process, an excessive amount of oxidant is input into the first annular channel;

[0021] During the gasification process, the combustible carbon-containing waste is conveyed through the second annular channel, and the combustible carbon-containing waste is the solid combustible carbon-containing waste or a slurry made of the solid combustible carbon-containing waste and the liquid carbon-containing waste;

[0022] During the gasification process, an oxidant is input into the third annular channel;

[0023] Preferably, the preparation of the slurry includes the following steps: drying and pulverizing the solid combustible carbon-containing waste into solid particles with an average particle size of 65 - 90 μm, and then mixing the solid particles with the liquid carbon-containing waste to obtain a slurry with a volume percentage of solid particles of 50 - 60%.

[0024] In some embodiments, during the gasification process, the gas velocity of the oxidant in the first annular channel is controlled to be 100 - 150 m / s, the material velocity of the second annular channel is controlled to be 1 - 2 m / s, and the gas velocity of the oxidant in the third annular channel is controlled to be 100 - 150 m / s; the gas velocity of the purge device is controlled to be 0.2 - 0.5 m / s; the temperature of the steam or carbon dioxide ejected from the purge port is controlled to be 350 - 450 °C.

[0025] The technical solution provided by the present invention has the following beneficial effects:

[0026] 1. For the gasifier provided by the present invention, the burner structure adopts a unique four-channel design. The central annular channel is a combustible waste gas channel. During the gasification process, the combustible waste gas reacts with the oxidant in the first annular channel to generate a large amount of heat. This thermal energy can heat the excessive oxidant input into the first annular channel and the carbon-containing waste in the adjacent second annular channel, achieving a self-heating effect, thereby saving external energy input.

[0027] 2. Carbon-containing waste, especially solid carbon-containing waste, usually contains some ash that cannot be gasified. After high-temperature gasification in the gasification chamber, the ash will melt into liquid slag, and the slag also contains a small amount of unreacted carbon. The present invention installs a purge device between the slag discharge port and the downcomer. The purge device is provided with a plurality of purge ports evenly spaced apart, so that the steam or carbon dioxide can be sprayed on the slag falling through the slag discharge port without dead angles in a 360° manner, which can promote the reaction of carbon in the slag, facilitate reducing the residual carbon content. After the reaction, the slag enters the quench chamber, improving the gasification efficiency and energy utilization rate.

[0028] 3. The gasifier of the present invention adopts a four-channel burner design and installs a purging device between the slag outlet and the downcomer. During operation, the combustible waste gas introduced through the central annular channel contacts and reacts with the oxidant introduced through the first annular channel. The combustible waste gas burns fully in the combustion space between the two. At the same time, the heat released during the combustion process can heat the excess oxidant introduced through the first annular channel, thereby providing excess high-temperature oxidant. The generated high-temperature oxidant can more easily ignite the combustible carbon-containing waste (such as liquid slurry) introduced through the second annular channel, promoting the gasification of the combustible carbon-containing waste. The outermost third annular channel further promotes the reaction, especially facilitating the atomization of the slurry. The reacted molten slag flows down from the gasification chamber to the vicinity of the slag outlet, reacts further after being purged by the purging device, and finally enters the quench chamber through the downcomer. The syngas generated by the reaction enters the downstream equipment after being washed and purified in the quench chamber. Through the gasifier of the present invention, industrial combustible waste gas and combustible carbon-containing waste (such as solid carbon-containing waste or slurry made therefrom) can be integrated in one gasifier. The combustible waste gas can be used to provide high energy to promote the gasification of solid carbon-containing waste, thereby generating syngas, which can be used for the synthesis of downstream chemical products, etc.

[0029] Using the gasifier of the present invention to gasify solid carbon-containing waste can simplify the pretreatment of solid carbon-containing waste. Solid carbon-containing waste has complex components and varying moisture contents. Based on the gasifier of the present invention, there is no need to adopt complex pretreatment processes. For example, only by simply drying and pulverizing the solid carbon-containing waste into powder particles, and then through gas-phase transportation or mixing the powder particles with organic waste liquid to make liquid slurry, the gasification process can be well completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic structural diagram of the gasifier;

[0031] Figure 2 It is a schematic structural diagram of the burner;

[0032] Figure 3 It is a schematic structural diagram of the central annular channel;

[0033] Figure 4 It is a schematic diagram of the installation position of the purging device;

[0034] Figure 5 It is a top view structural schematic diagram of the annular purging pipeline of the purging device. DETAILED DESCRIPTION OF THE INVENTION

[0035] In order to better understand the technical solution of the present invention, the content of the present invention will be further elaborated below in conjunction with embodiments. However, the content of the present invention is not limited to the following embodiments only.

[0036] In this specification, orientation terms such as up, down, left, right, front, back, front side, back side, top, bottom, etc., which are mentioned or may be mentioned, are defined relative to the structures shown in the respective drawings. They are relative concepts and may accordingly change depending on their different positions and different usage states.

[0037] See Figures 1-5 , the carbon-containing waste gasifier provided by the present invention, like conventional gasifiers in the art, includes a gasification chamber 2, a quench chamber 3, a downcomer 6, and a bottom slag outlet 5. The quench chamber 3 is located below the gasification chamber 2. A bottom slag outlet 5 is provided at the bottom of the gasification chamber 2. A downcomer 6 is provided directly below the bottom slag outlet 5. The downcomer 6 extends vertically into the inner cavity of the quench chamber 3. A burner 1 is installed at the top of the gasification chamber 2. For the same or similar parts as those of the conventional gasifier, they will not be described in detail one by one. Those skilled in the art can understand or know according to the conventional techniques or common general knowledge in the technical field of gasifiers. The following will focus on the improvements of the gasifier developed by the present invention for the gasification of carbon-containing waste.

[0038] The burner 1 of the gasifier provided by the present invention is designed with four channels. See Figure 2, Specifically, the burner 1 includes a central annular channel 8 for inputting combustible waste gas, a first annular channel 9 for inputting an oxidant, a second annular channel 10 for inputting combustible carbon-containing waste, and a third annular channel 11 for inputting an oxidant. Among these four channels, the first annular channel 9 is located outside the central annular channel 8, the second annular channel 10 is located outside the first annular channel 9, and the third annular channel 11 is located outside the second annular channel 10, thus forming a four-channel structure nested in sequence from the inside to the outside. The four channels are all vertically arranged, and the top of each channel is the inlet and the bottom is the outlet. Among them, there is a space 17 between the outlet at the bottom of the central annular channel 8 and the outlet at the bottom of the first annular channel 9. This space serves as the space for the combustible waste gas output from the central annular channel 8 to contact and react with the oxidant in the first annular channel 9, that is, as a combustion space or an autothermal chamber. Specifically, the length of the central annular channel 8 is shorter than that of the first annular channel 9. The combustible waste gas output from the central annular channel 8 first enters the first annular channel 9 and reacts with the oxidant therein. During the operation of the gasifier, with this structural design, a large amount of heat is generated by the reaction of the combustible waste gas and the oxidant in the first annular channel 9, thereby heating the excess oxidant in the first annular channel 9 to provide a high-temperature excess oxidant, achieving an autothermal effect; at the same time, it can also heat the combustible carbon-containing waste in the adjacent second annular channel 10, reducing the input of external heat; and because a high-temperature excess oxidant can be generated in this way, the combustible carbon-containing waste, especially the slurry, in the second annular channel 10 is easier to ignite and gasify. Further, a third annular channel 11 is provided on the outermost side of the burner 1. The oxidant output through this channel can, on the one hand, promote the gasification reaction of the combustible waste, and on the other hand, atomize the combustible waste slurry, thus better promoting the gasification of the slurry-like combustible waste.

[0039] See Figure 1 and Figures 4-5 , A purging device 4 is also installed between the slag discharge port 5 and the downcomer 6. A purging port 16 is provided on the purging device 4. There are multiple purging ports 16, and each purging port 16 is evenly spaced. The function of the purging device 4 is to spray steam or carbon dioxide onto the molten slag falling through the slag discharge port 5, so that the molten slag can further fully react before entering the quench chamber 3 through the downcomer 6, reducing the residual carbon content. And by evenly spacing each purging port 16, when the liquid molten slag falls through the slag discharge port 5 and finally enters the quench chamber 3, it can be purged in a 360° annular gap, realizing the further reaction of the residual carbon in the molten slag and reducing the residual carbon content to a greater extent.

[0040] Participate Figure 2, Further, the wall thickness of the bottom outlet of the central annular channel 8 is designed to be thinned, that is, thinner than the wall thickness of the rest of the central annular channel 8, so that the wall thickness of the end face of the bottom outlet of the central annular channel 8 is 0.4 - 0.6 mm, for example, 0.5 mm; with this structural design, a flashback flame can be formed by the reaction between the combustible waste gas in the central annular channel 8 and the oxidant in the first annular channel 9 (as Figure 1 shown schematically), thereby reducing the influence of high temperature on the burner 1 and prolonging the service life of the burner.

[0041] Further, as Figure 2 , the outlet at the bottom of the first annular channel 9 is designed such that the outlet direction (i.e., the discharging direction) is vertical, that is, there is no angle in the outlet direction. During operation, specifically, the oxidant gas velocity in the first annular channel 9 can be controlled to be, for example, 100 - 150 m / s; the oxidant at high temperature is output vertically downward by the first annular channel 9. The outlet directions (i.e., the discharging directions) at the bottoms of the second annular channel 10 and the third annular channel 11 are both designed to be inclined downward towards the central axis of the burner 1, and the included angle between the outlet direction and the central axis of the burner 1 (as Figure 2 shown by the dashed line in) is 50 - 60 degrees. During operation, specifically, the material velocity in the second annular channel 10 can be controlled to be, for example, about 1 - 2 m / s, and the oxidant gas velocity in the third annular channel 11 can be controlled to be, for example, about 100 - 150 m / s. By designing the outlet directions of these channels in this way, the combustible carbon-containing waste, especially the slurry, output from the second annular channel 10 will come into full contact with the high-temperature excess oxidant output vertically downward by the first annular channel 9, which is conducive to the heating up and gasification reaction of the material; at the same time, the oxidant output from the third annular channel 11 will also come into more full contact with the combustible carbon-containing waste, especially the slurry, output from the second annular channel 10 to promote the reaction, especially can promote the atomization of the slurry.

[0042] More specifically, referring to Figure 1 、 4 -5, the purging device 4 installed between the slag tap 5 and the downcomer 6 has the opening direction of the purge port 16 (i.e., the gas outlet direction, Figure 4 the inclined dashed line in is the schematic of this direction) set such that the injection direction of the steam or carbon dioxide is inclined downward, and the included angle 13 between this injection direction and the central axis of the gasifier (as Figure 4 shown by the vertical dashed line in) is 30 - 45 degrees. With such a purge port design, it is beneficial to prevent the molten slag from splashing, thereby avoiding the blockage of the slag tap 5. In specific applications, the purge gas velocity can be controlled to be 0.2 - 0.5 m / s.

[0043] Furthermore, the purging device 4 specifically includes an annular purging pipeline 15 and a gas supply pipeline 7. The gas supply pipeline 7 is connected to the annular purging pipeline 15 and is used to supply purging gas, namely carbon dioxide or water vapor. Specifically, the gas supply pipeline 7 is connected to a water vapor source or a carbon dioxide source (not shown in the figure). The water vapor source or the carbon dioxide source is, for example, a corresponding gas storage tank, or other process pipelines or equipment that can provide water vapor or carbon dioxide. A plurality of purging ports 16 are formed in the annular purging pipeline 15, specifically on the inner side of the annular purging pipeline 15, so as to spray the corresponding purging gas onto the molten slag falling through the slag discharge port 5. In some embodiments, the annular purging pipeline 15 can be a circular coiled pipe. Among the purging ports 16 formed thereon, the purging ports 16 located on the same circumference are equally spaced, so as to achieve a 360° purging effect. The specific fixing method of the purging device 4 is not particularly limited as long as the fixing purpose can be achieved. For example, a fixing ring 14 can be arranged outside the annular purging pipeline. The fixing ring 14 is tightly connected to the annular purging pipeline 15, and at the same time, the fixing ring 14 is fixedly connected to the bottom of the slag discharge port 5, so that the purging device 4 is fixed at the position between the slag discharge port 5 and the downcomer 6. Of course, this is only an example of a fixing method, and other conventional fixing methods are not excluded. Preferably, the purging port 16 can be designed as an elongated purging port, which is more conducive to the spraying of the purging gas.

[0044] The carbon-containing waste gasifier provided by the present invention is particularly suitable for gasifying carbon-containing waste. The carbon-containing waste that can be gasified includes solid combustible carbon-containing waste, and further can include liquid carbon-containing waste, and can also include gaseous combustible carbon-containing waste.

[0045] Among them, the solid combustible carbon-containing waste includes, for example, but is not limited to sludge, livestock and poultry waste, straw, shredded wood chips, kitchen waste and other carbon-containing combustible solid waste. Preferably, the carbon content of the solid combustible carbon-containing waste is more than 60 wt%. The liquid carbon-containing waste is, for example, a chemical waste liquid containing organic matter, such as a phenolic wastewater, black water and other chemical waste liquids that are difficult to treat. The gaseous combustible carbon-containing waste is, for example, the excess coke oven gas generated by a chemical plant.

[0046] Based on the gasifier provided by the present invention, the present invention also provides a method for gasifying carbon-containing waste. When the gasifier of the present invention is used to gasify combustible carbon-containing waste, during the gasification process, the combustible waste gas is transported through the central annular channel 8 of the burner 1. The combustible waste gas can be gaseous combustible carbon-containing waste or carbon-free combustible waste gas. The gaseous combustible carbon-containing waste is as described above and will not be repeated; the carbon-free combustible waste gas is, for example, excess hydrogen produced by a chemical plant. During the gasification process, an excess amount of oxidant is input into the first annular channel 9 of the burner 1. During the gasification process, the combustible carbon-containing waste is transported through the second annular channel 10 of the burner 1. The combustible carbon-containing waste can be the solid combustible carbon-containing waste described above, or a slurry made of solid combustible carbon-containing waste and liquid carbon-containing waste; preferably, a slurry made of solid combustible carbon-containing waste and liquid carbon-containing waste is used for easy transportation. During the gasification process, an oxidant is input into the third annular channel 11. Among them, it is preferred to prepare the slurry introduced into the second annular channel 10 according to the following steps:

[0047] The solid combustible carbonaceous waste is dried, for example, at low temperature until the external water content is 0, and the low temperature drying is performed, for example, at a condition below 100°C. After drying, the solid waste is crushed to obtain solid particles with an average particle size of 65-90 μm (for example, 75 μm), and then the solid particles are mixed with liquid carbonaceous waste to prepare a slurry with a solid particle volume percentage of 50-60%. In the prior art, the concentration of gasification slurry, such as water-coal slurry, usually needs to be higher than 60% to make the gasifier run stably and smoothly. This is because a large amount of water takes away heat during the gasification process; in the present invention, the energy is provided by the combustible gas in the central annular channel 8, which can reduce the influence of the heat taken away by water, so that the particle solubility of the slurry can be reduced to a level below 60%.

[0048] During the gasification process, as is conventional in the art, an ignition device such as an oil gun is used for ignition; the combustible waste gas in the central annular channel 8 is ignited and reacts with the oxidant, so that the energy can be provided by the combustible waste gas. The combustible waste gas and the oxidant react in the combustion space in the first annular channel 9 to release a large amount of heat, and the excess oxidant in the first annular channel 9 is heated, so that a high-temperature excess oxidant can be formed to achieve the self-heating effect; moreover, the heat can be further transferred to the adjacent second annular channel 10 to heat the combustible carbon-containing waste in this channel. At the same time, due to the generation of the high-temperature excess oxidant, it is easier to ignite the combustible carbon-containing waste, especially the slurry, in the second annular channel 10, which can promote the gasification of the slurry. The oxidant in the third annular channel 11 is beneficial to the atomization of the slurry and promotes the reaction. At the channel outlet, by optimizing the design of the outlets of the first, second, and third annular channels and matching them in the preferred outlet directions as described above, the materials output from these channels can also form better contact, fully promoting the gasification reaction. Moreover, the oxidant in the third annular channel 11 can also promote the atomization of the slurry and further promote the progress of the gasification reaction. The oxidants in the first annular channel 9 and the third annular channel 11 of the burner 1 are conventional in the art, for example, oxygen or a gas containing oxygen, such as a gas with an oxygen volume content of more than 60%, for example, a gas with an oxygen volume content of 60%-70%.

[0049] During the gasification process, preferably, the gas velocity of the oxidant in the first annular channel 9 is controlled to be 100-150 m / s, the material velocity of the second annular channel 10 is controlled to be 1-2 m / s, and the gas velocity of the oxidant in the third annular channel 11 is controlled to be 100-150 m / s; the gas velocity of the combustible waste gas in the central annular channel can be about 50 m / s (for example, 45-55 m / s); by adopting the preferred material velocity control, it is beneficial for the materials conveyed in the burner 1 to have more sufficient contact reaction at the outlet and for the gasification reaction to proceed more fully. Preferably, the purge gas velocity of the purge device 4 is controlled to be 0.2-0.5 m / s. On the one hand, it can effectively purge the slag, and on the other hand, it can further avoid the possibility of splashing.

[0050] The slag generated in the gasification chamber 2 after the reaction will flow downward along the furnace wall to near the slag outlet 5, and after being purged by the purge device 4 installed below the slag outlet 5, it will further react and finally enter the quench chamber 3 through the downcomer 6. As is conventional in the art, the syngas generated by the gasification reaction will enter the downstream equipment after being washed in the quench chamber 3, and this will not be elaborated here.

[0051] In summary, by using the gasifier of the present invention, combustible waste gases such as industrial combustible waste gases and solid carbon-containing waste can be conveniently integrated into a gasifier for gasification to produce more valuable synthesis gas. Thereby, the energy waste and secondary pollution caused by directly using these wastes as fuel or landfilling in the prior art are avoided. Moreover, based on the gasifier of the present invention, it can be utilized under the condition that the solid carbon-containing waste only undergoes simple pretreatment, simplifying the pretreatment process of waste utilization and making it easier to implement and promote industrially. At the same time, based on the gasifier of the present invention, through the ingenious design of the burner structure and the purging device, not only can the heat provided by the combustion of its own materials be fully utilized, reducing the external heat input and the oven drying time to achieve an energy-saving effect, but also the carbon-containing waste can be gasified more fully, reducing the residual carbon content; that is, it can improve the gasification effect and energy utilization rate.

[0052] The following is further described in combination with specific application cases.

[0053] Example 1

[0054] Refer to Figures 1-5 , and use the gasifier described above to gasify the carbon-containing waste. Among them, the wall thickness of the outlet end face of the central annular channel 8 of the gasifier is 0.5 mm, the purging port 16 is set to have an included angle of 45 degrees between the spraying direction and the central axis of the gasifier, and the purging gas sprayed is water vapor at a temperature of 400 °C; the outlet directions at the bottoms of the second annular channel 10 and the third annular channel 11 form an included angle of 55 degrees with the central axis of the burner 1.

[0055] In this embodiment, the combustible waste gas introduced into the central annular channel 8 of the burner 1 is coke oven gas, the oxidant introduced into the first annular channel 9 and the third annular channel 11 is oxygen; the combustible carbon-containing waste introduced into the second annular channel 10 is a slurry made of solid combustible carbon-containing waste and liquid combustible carbon-containing waste.

[0056] Among them, in the slurry, the solid combustible carbon-containing waste used is carbon-containing sludge (carbon content is about 70%), and the liquid carbon-containing waste used is phenol-containing wastewater. Before preparing the slurry, the solid combustible carbon-containing waste is dried to an external moisture of 0 and pulverized to 75 μm; the solid particles and the liquid carbon-containing waste are mixed to form a slurry, and the volume percentage of the solid particles in the slurry is 50%.

[0057] During the gasification process, the following parameters are controlled within the following ranges: the oxidant gas velocity in the first annular channel 9 is controlled to be 100 - 150 m / s, the material velocity in the second annular channel 10 is controlled to be 1 - 2 m / s, the oxidant gas velocity in the third annular channel 11 is controlled to be 100 - 150 m / s; the gas velocity of the combustible waste gas in the central annular channel 8 is controlled to be about 50 m / s; the purging gas velocity of the purging device 4 is controlled to be 0.2 - 0.5 m / s. After gasification, the residual carbon content of the molten slag is between 2 - 3%.

[0058] In addition, the inventor also carried out gasification of livestock and poultry waste as solid combustible carbon-containing waste according to the same process as in Example 1 based on the above gasifier. After gasification, the residual carbon content of the molten slag is also between 2 - 3%.

[0059] Comparative Example 1

[0060] A conventional gasifier in the art is used. Among them, the burner has three channels. Both the outer annular channel and the central channel are fed with oxidant, and the annular gap channel between the outer annular channel and the central channel is fed with coal slurry (the carbon content is similar to that in Example 1). The gas velocity control of the corresponding materials is the same as that in Example 1 and will not be elaborated here. After gasification, the residual carbon content of the molten slag is relatively high, between 7 - 8%.

[0061] Those skilled in the art can understand that under the teaching of this specification, some modifications or adjustments can be made to the present invention. These modifications or adjustments should also be within the scope defined by the claims of the present invention.

Claims

1. A carbon-containing waste gasifier, the gasifier comprising a gasification chamber and a quench chamber provided below the gasification chamber, a slag discharge port being provided at the bottom of the gasification chamber, a downcomer vertically extending into the inner cavity of the quench chamber being provided directly below the slag discharge port, and a burner being installed at the top of the gasification chamber, characterized in that the burner includes a central annular channel for inputting combustible waste gas, a first annular channel for inputting an oxidant, a second annular channel for inputting combustible carbon-containing waste, and a third annular channel for inputting an oxidant, which are sequentially sleeved from the inside to the outside, an inlet being provided at the top of each of the channels and an outlet being provided at the bottom; a combustion space for the reaction of the combustible waste gas and the oxidant is left between the outlet at the bottom of the central annular channel and the outlet at the bottom of the first annular channel, and the combustion space can also heat the excess oxidant in the first annular channel and heat the combustible carbon-containing waste in the second annular channel; a purging device is installed between the slag discharge port and the downcomer, a purging port for jetting steam or carbon dioxide to the molten slag falling through the slag discharge port is provided on the purging device, a plurality of the purging ports are provided, and the purging ports are evenly spaced apart.

2. The carbon-containing waste gasifier according to claim 1, wherein, the wall thickness of the central annular channel is thinned at the bottom outlet thereof, and the wall thickness of the outlet end face of the central annular channel is 0.4 mm - 0.6 mm.

3. The carbon-containing waste gasifier according to claim 1, wherein the purging port is arranged such that the jetting direction of the steam or carbon dioxide is inclined downward and the included angle between the jetting direction and the central axis of the gasifier is 30 - 45 degrees.

4. The carbon-containing waste gasifier according to claim 3, wherein the purging device includes an annular purging pipeline and a gas supply pipeline connected to the annular purging pipeline, and the gas supply pipeline is connected to a steam gas source or a carbon dioxide gas source; a plurality of the purging ports are provided on the annular purging pipeline.

5. The carbon-containing waste gasifier according to claim 4, characterized in that, the annular purging pipeline is a circular coiled pipe, and the purging ports located on the same circumference are equally spaced apart.

6. The carbon-containing waste gasifier according to any one of claims 1-5, characterized in that, the outlet direction at the bottom of the first annular channel is the vertical direction; the outlet directions at the bottoms of the second annular channel and the third annular channel are both inclined downward toward the central axis of the burner and form an included angle of 50 - 60 degrees with the central axis of the burner.

7. The carbon-containing waste gasifier according to any one of claims 1-5, characterized in that, the combustible carbon-containing waste conveyed by the second annular channel is solid combustible carbon-containing waste or combustible carbon-containing waste slurry.

8. A gasification method for carbon-containing waste, characterized in that, using the carbon-containing waste gasifier according to any one of claims 1 - 7 to gasify the carbon-containing waste; wherein the carbon-containing waste includes solid combustible carbon-containing waste.

9. The gasification method according to claim 8, characterized in that, the carbon-containing waste further includes liquid carbon-containing waste.

10. The gasification method according to claim 9, characterized in that, the carbon-containing waste further includes gaseous combustible carbon-containing waste.

11. According to the gasification method of claim 10, characterized in that during the gasification process, the combustible waste gas is conveyed through the central annular channel, and the combustible waste gas is the gaseous combustible carbon-containing waste or carbon-free combustible waste gas; during the gasification process, an excess of oxidant is input into the first annular channel; during the gasification process, the combustible carbon-containing waste is conveyed through the second annular channel, and the combustible carbon-containing waste is the solid combustible carbon-containing waste or slurry made from the solid combustible carbon-containing waste and the liquid carbon-containing waste; During the gasification process, an oxidant is input into the third annular channel.

12. The gasification method according to claim 11, characterized in that, The preparation of the slurry includes the following steps: drying and pulverizing the solid combustible carbon-containing waste into solid particles with an average particle size of 65 - 90 μm, and then mixing the solid particles with the liquid carbon-containing waste to obtain a slurry with a volume percentage of solid particles of 50 - 60%.

13. The gasification method according to any one of claims 8-12, characterized in that, During the gasification process, control the oxidant gas velocity in the first annular channel to be 100 - 150 m / s, control the material velocity in the second annular channel to be 1 - 2 m / s, and control the oxidant gas velocity in the third annular channel to be 100 - 150 m / s; control the purge gas velocity of the purge device to be 0.2 - 0.5 m / s; control the temperature of the steam or carbon dioxide ejected from the purge port to be 350 - 450 °C.

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