Nozzle for biomass water vapor gasification

Abstract

The invention relates to a nozzle for biomass steam gasification, and belongs to the technical field of biomass combustion equipment. A nozzle for biomass water vapor gasification comprises a static pressure box and a pre-combustion chamber which are communicated up and down to form a whole. A primary air pipeline is arranged in the static pressure box, an anti-backfire valve is arranged at the tail end of the static pressure box, and the tail end of the primary air pipeline penetrates through the anti-backfire valve and stops at the upper end of the pre-combustion chamber; the pre-combustion chamber is in a horn mouth shape with a downward opening, a plurality of water vapor pipelines penetrate through the periphery of the side wall of the pre-combustion chamber from top to bottom, and water vapor nozzles are formed in the lower ends of the water vapor pipelines. Biomass powder and primary air are evenly mixed and then enter the pre-combustion chamber, primary combustion is conducted at the front end of the pre-combustion chamber under the action of an ignition opening, a primary reaction product is evenly mixed with water vapor at the rear section of the pre-combustion chamber under driving of carrier gas, further gasification is conducted, and grading control over gasification reaction is achieved.

Description

Technical Field

[0001] This invention relates to a nozzle for biomass steam vaporization, belonging to the technical field of biomass combustion equipment. Background Technology

[0002] Biomass is the only renewable carbon-based energy source in nature. Gasification technology can convert biomass into small-molecule syngas such as H2, CO2, and CO, which can then be used as raw materials for the production of chemical products such as green methanol. Common gasifying agents include air, oxygen, water vapor, or mixtures thereof. Studies have shown that using water vapor as a gasifying agent can enable a water-gas reaction under high-temperature conditions, effectively increasing the H2 and CO content in the gaseous products and improving gasification efficiency.

[0003] Entrained flow biomass gasification typically uses high-pressure nitrogen or similar carrier gas to transport biomass powder to the gasifier via a pneumatic conveying system. To control the effective components of the gasification products, the material residence time during the gasification process must be kept extremely short. Existing burners are mostly designed for coal as feedstock. Due to the poor flowability of biomass, current feeding methods suffer from uneven feeding and poor stability. Furthermore, due to the hygroscopic nature of biomass, directly mixing biomass with steam for gasification easily leads to material agglomeration or clumping, hindering material dispersion and complete reaction, and easily causing nozzle blockage. These methods fail to meet the high-efficiency process requirements of entrained flow biomass gasification.

[0004] Citations of existing technical documents:

[0005] Chinese patent document with publication date of September 12, 2025, publication number CN120624066A, and title "Nozzle for biomass powder gasification, gasifier and biomass powder gasification method". Summary of the Invention

[0006] The purpose of this invention is to provide a nozzle for biomass steam gasification, which, compared with the prior art, enables uniform feeding of biomass powder, uniform mixing of primary air, steam and fuel, and staged reaction of primary air, steam and fuel.

[0007] The present invention adopts the following technical solution:

[0008] A nozzle for biomass steam gasification includes a static pressure chamber 4 and a pre-combustion chamber 16, which are connected vertically to form an integral unit. A primary air duct 3 is installed inside the static pressure chamber 4, and a backfire prevention valve 15 is installed at the end of the static pressure chamber 4. The end of the primary air duct 3 passes through the backfire prevention valve 15 and terminates at the upper end of the pre-combustion chamber 16. The pre-combustion chamber 16 is shaped like a flared mouth with its opening facing downwards. Multiple steam pipes 11 pass through the side wall of the pre-combustion chamber 16 from top to bottom, and the lower end of the steam pipes 11 has a steam nozzle 12.

[0009] After the biomass powder is uniformly mixed with primary air, it enters the pre-combustion chamber. Under the action of the ignition port, it undergoes initial combustion at the front end of the pre-combustion chamber. The initial reaction products are uniformly mixed with water vapor in the rear section of the pre-combustion chamber under the drive of the carrier gas, and further gasification occurs, thus achieving staged control of the gasification reaction.

[0010] Preferably, the pre-combustion chamber 16 is conical, and multiple steam pipes 11 are evenly distributed at equal angles around the pre-combustion chamber 16. The steam nozzles 12 are inclined at an angle toward the central axis of the pre-combustion chamber 16. Steam is delivered to the rear end of the pre-combustion chamber through the steam pipes 11 located at three equal points on the circumference of the pre-combustion chamber's cross-section. The steam nozzles at the ends of the pipes are set as centripetal slopes, thus enabling the steam to converge toward the center of the pre-combustion chamber and mix evenly with the initial reaction products.

[0011] Preferably, the upper end of the primary air duct 3 extends laterally out of the static pressure box 4 to form a primary air inlet 6; an ignition gun is provided in the middle of the primary air duct 3, and the end of the ignition gun extends out of the lower end of the primary air duct 3.

[0012] Preferably, the static pressure box 4 has a biomass feed port 7 on its side wall, and the primary air duct 3 is coaxially equipped with a hydrocyclone 13, the position of which corresponds to the biomass feed port 7. Biomass powder is tangentially fed into the carrier gas duct through the feed port. Because it is fed at an inclined angle, it will not clump, and the biomass powder and carrier gas are uniformly mixed.

[0013] Preferably, the upper part of the static pressure box 4 is also provided with a carrier gas inlet 1, which is used to supply air from top to bottom along the static pressure box 4 and send the biomass downward into the pre-combustion chamber 16. The carrier gas enters the static pressure box through the carrier gas inlet, and the carrier gas in the static pressure box can be uniformly sent into the carrier gas pipeline. Under the action of the cyclone separator, it is uniformly mixed with the biomass powder, thus achieving uniform and even conveying of the biomass powder.

[0014] Preferably, the gas medium in the carrier gas outlet 1 is nitrogen, and an electric air valve 2 is installed on the carrier gas outlet 1.

[0015] Preferably, the steam pipe 11 is equipped with electric air valves 9, 18, and 17, and the steam pipe 11 is covered with a heat insulation layer 10.

[0016] The beneficial effects of this invention are as follows:

[0017] 1) Core beneficial effects: After the biomass powder is uniformly mixed with primary air, it enters the pre-combustion chamber. Under the action of the ignition port, it undergoes initial combustion at the front end of the pre-combustion chamber. The initial reaction products are uniformly mixed with water vapor in the rear section of the pre-combustion chamber under the drive of the carrier gas, and further gasification occurs, realizing the staged control of the gasification reaction.

[0018] 2) Further beneficial effects: Under the pressure of the carrier gas delivery, the anti-backfire valve flap opens to the pre-combustion chamber side to realize the delivery of carrier gas and biomass powder. When the reaction in the furnace is violent and the pressure increases sharply, the pressure in the furnace pushes the valve flap to close, thus preventing backfire.

[0019] 3) Further beneficial effects: Water vapor is sent into the rear end of the pre-combustion chamber through a water vapor pipeline located at three equal points on the circumference of the pre-combustion chamber. The water vapor nozzle at the end of the pipeline is set as a centripetal slope, so that water vapor can be gathered towards the center of the lower part of the pre-combustion chamber and mixed evenly with the initial reaction products.

[0020] 4) Biomass powder is tangentially fed into the carrier gas pipeline through the feed port. Because it is fed at an inclined angle, it will not clump together, and the biomass powder and carrier gas are uniformly mixed.

[0021] 5) The carrier gas enters the static pressure box through the carrier gas inlet. The carrier gas in the static pressure box can be uniformly sent into the carrier gas pipeline. Under the action of the hydrocyclone, it is uniformly mixed with the biomass powder, thus achieving uniform and even delivery of the biomass powder. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the spray for biomass water vapor gasification according to the present invention (the left side of the figure is the upper end, and the right side is the lower end).

[0023] Figure 2 This is a schematic diagram of a biomass feed inlet;

[0024] Figure 3 This is a schematic diagram of the structure of a steam-powered air valve and a biomass nozzle.

[0025] Among them: 1-Carrier gas supply outlet, 2-Electric air valve, 3-Primary air pipeline, 4-Static pressure box, 5-Ignition gun, 6-Primary air inlet, 7-Biomass feed inlet, 8-Steam inlet, 9, 17, 18-Electric air valve, 10-Insulation layer, 11-Steam pipeline, 12-Steam nozzle, 13-Cyclone separator, 14-Carrier gas pipeline, 15-Backfire prevention valve, 16-Pre-combustion chamber. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0027] See Figure 1 In this embodiment, the nozzle for biomass steam gasification is actually placed vertically. Figure 1 In the middle, the left end is the upper end, and the right end is the lower end.

[0028] like Figure 1A nozzle for biomass steam vaporization includes a static pressure chamber 4 and a pre-combustion chamber 16, which are connected vertically to form an integral unit. A primary air duct 3 is installed inside the static pressure chamber 4, and a backfire prevention valve 15 is installed at the end of the static pressure chamber 4. The end of the primary air duct 3 passes through the backfire prevention valve 15 and terminates at the upper end of the pre-combustion chamber 16. The pre-combustion chamber 16 is shaped like a flared mouth with its opening facing downwards. Multiple steam pipes 11 pass through the side wall of the pre-combustion chamber 16 from top to bottom, and the lower end of the steam pipes 11 has a steam nozzle 12.

[0029] After the biomass powder is uniformly mixed with primary air, it enters the pre-combustion chamber. Under the action of the ignition port, it undergoes initial combustion at the front end of the pre-combustion chamber. The initial reaction products are uniformly mixed with water vapor in the rear section of the pre-combustion chamber under the drive of the carrier gas, and further gasification occurs, thus achieving staged control of the gasification reaction.

[0030] In this embodiment, see Figure 1 The pre-combustion chamber 16 is conical. Figure 1 Only one of the 11 water vapor pipelines is shown; there are actually three. (The details can be combined.) Figure 3 Multiple steam pipes 11 are evenly distributed at equal angles around the pre-combustion chamber 16.

[0031] like Figure 1 As shown, the steam nozzle 12 has an inclination angle toward the central axis of the pre-combustion chamber 16. Steam is delivered to the rear end of the pre-combustion chamber through a steam pipe 11 located at three equal points on the circumference of the pre-combustion chamber. The steam nozzle at the end of the pipe is set as a centripetal slope, so that the steam can be concentrated toward the center of the pre-combustion chamber and uniformly mixed with the initial reaction products.

[0032] like Figure 1 As shown, the upper end of the primary air duct 3 extends laterally out of the static pressure box 4 to form a primary air inlet 6; an ignition gun is provided in the middle of the primary air duct 3, and the end of the ignition gun extends out of the lower end of the primary air duct 3.

[0033] In this embodiment, a biomass feed port 7 is provided on the side wall of the static pressure box 4, and a hydrocyclone 13 is coaxially arranged on the primary air duct 3, with the position of the hydrocyclone 13 corresponding to the biomass feed port 7. Biomass powder is tangentially fed into the carrier gas duct through the feed port. Because it is fed at an inclined angle, it will not clump, and the biomass powder and carrier gas are uniformly mixed.

[0034] In this embodiment, a carrier gas inlet 1 is also provided at the upper part of the static pressure box 4 for supplying air from top to bottom along the static pressure box 4 and sending the biomass downward into the pre-combustion chamber 16. The carrier gas enters the static pressure box through the carrier gas inlet, and the carrier gas in the static pressure box can be uniformly sent into the carrier gas pipeline. Under the action of the cyclone separator, it is uniformly mixed with the biomass powder, thus achieving uniform and even delivery of the biomass powder.

[0035] In this embodiment, the gas medium of the carrier gas outlet 1 is nitrogen, and an electric air valve 2 is provided on the carrier gas outlet 1.

[0036] In this embodiment, combined with Figure 3 The steam pipe 11 is equipped with electric air valves 9, 18, and 17, and the steam pipe 11 is covered with a heat insulation layer 10.

[0037] During operation, the carrier gas enters the static pressure box 4 through the carrier gas inlet 1, and then is evenly introduced into the carrier gas pipeline 14. The biomass powder, carried by the carrier gas, enters the carrier gas pipeline 14 at a tangential angle through the feed inlet 7. Driven by the hydrocyclone 13, the biomass powder and the carrier gas are evenly mixed and conveyed into the furnace at a uniform speed.

[0038] Primary air enters the primary air duct 3 through the primary air inlet 6, mixes with the biomass powder transported by the carrier gas, and then enters the front section of the pre-combustion chamber 16 after passing through the backfire prevention valve 15. Under the action of the ignition gun 5, it undergoes initial combustion. The primary air provides a small amount of oxygen for the initial combustion of the biomass powder.

[0039] It should be noted that the concept of "primary air" is a professional term in the field of fuel combustion / gasification. It refers to the airflow that directly carries fuel and provides a small amount of oxygen / air for the initial ignition / thermal cracking of the fuel. It is a classification of the air supply system relative to secondary air and tertiary air, and it is a standard design in pulverized coal boilers and biomass combustion / gasification equipment. The core reason why it is called "primary air" is that it provides the "first basic air supply" for fuel combustion / gasification in terms of air supply timing and priority. It is a prerequisite for the initial reaction of the fuel. The subsequent supplementary combustion / mixing airflow is called secondary air and tertiary air, respectively.

[0040] Combination Figure 3 The steam is divided into three streams, which enter the steam pipeline under the action of electric air valve 9, electric air valve 17 and electric air valve 18 respectively. The three steam pipelines are welded to three equal parts of the circumference of the pre-combustion chamber. The nozzle of each steam pipeline is set as a centripetal inclined surface, so the steam can gather towards the center of the pre-combustion chamber and mix evenly with the initial reaction products to produce a steam vaporization reaction.

[0041] Explanation of related component names:

[0042] Carrier gas pipeline: The carrier gas enters through the carrier gas pipeline and drives the biomass powder to flow evenly through the hydrocyclone.

[0043] Biomass powder feed port 7: Biomass powder enters the carrier gas pipeline at a tangential angle through the feed port and is uniformly mixed with the carrier gas under the action of the hydrocyclone.

[0044] Backfire prevention valve 15: The backfire prevention valve consists of 6 valve discs. In the static state, the valve discs are closed by the hinge. The length of the valve discs is greater than the radius difference between the carrier gas pipeline and the primary air pipeline, and the angle when closed is biased towards the pre-combustion chamber to achieve a one-way check function. Under the pressure of the carrier gas delivery, the valve discs open towards the pre-combustion chamber side to realize the delivery of carrier gas and biomass powder. The horizontal distance between the backfire prevention valve and the pre-combustion chamber opening is less than the length of the valve discs to prevent the valve discs from completely sticking to the carrier gas pipeline wall when open. When the reaction in the furnace is violent and the pressure increases sharply, the pressure in the furnace pushes the valve discs to close, thereby blocking backfire.

[0045] Steam pipe 11: Three steam pipes are connected to the outside of the pre-combustion chamber, respectively located at three equal parts of the circumference of the pre-combustion chamber. The outer surface of the pipes is covered with a heat insulation layer, and the steam nozzle at the end of the pipe is set as an inclined surface to realize the concentration of steam towards the center of the pre-combustion chamber.

[0046] Pre-combustion chamber 16: Biomass powder is uniformly mixed with primary air and then enters the pre-combustion chamber. Under the action of the ignition port, it undergoes initial combustion at the front end of the pre-combustion chamber. The initial reaction products are uniformly mixed with water vapor in the rear section of the pre-combustion chamber under the action of the carrier gas, and further gasification occurs.

[0047] Static pressure box 4: The carrier gas enters the carrier gas pipeline evenly through the static pressure box, and then enters the furnace after the biomass powder is evenly mixed.

[0048] The core beneficial effects of this invention are as follows: after the biomass powder is uniformly mixed with primary air, it enters the pre-combustion chamber and undergoes initial combustion at the front end of the pre-combustion chamber under the action of the ignition port. The initial reaction products are uniformly mixed with water vapor in the rear section of the pre-combustion chamber under the drive of the carrier gas, and further gasification occurs, thereby realizing the staged control of the gasification reaction.

[0049] A further beneficial effect is that, driven by the carrier gas delivery pressure, the anti-backfire valve disc opens towards the pre-combustion chamber side, enabling the delivery of carrier gas and biomass powder. When the reaction inside the furnace is intense, causing a sharp increase in pressure, the furnace pressure pushes the valve disc to close, thus preventing backfire. It should be noted that although the concept of the anti-backfire valve itself is known, its application in the specific field of this invention is innovative.

[0050] Further beneficial effect two: Water vapor is sent into the rear end of the pre-combustion chamber through a water vapor pipeline located at three equal points on the circumference of the pre-combustion chamber. The water vapor nozzle at the end of the pipeline is set as a centripetal slope, so that water vapor can be gathered towards the center of the lower part of the pre-combustion chamber and mixed evenly with the initial reaction products.

[0051] Further beneficial effect three: Biomass powder is tangentially fed into the carrier gas pipeline through the feed port. Because it is fed at an inclined angle, it will not clump, and the biomass powder and carrier gas are uniformly mixed.

[0052] Further beneficial effect four: The carrier gas enters the static pressure box through the carrier gas outlet. The carrier gas in the static pressure box can be uniformly delivered into the carrier gas pipeline. Under the action of the hydrocyclone, it is uniformly mixed with the biomass powder, thus achieving uniform and even delivery of the biomass powder.

[0053] In summary, this invention can realize biomass steam gasification, make full use of various fuel resources, improve gasification efficiency, reduce pollution emissions, and has good application prospects and economic benefits.

[0054] The above are preferred embodiments of the present invention. Those skilled in the art can make various modifications or improvements based on these embodiments. Without departing from the overall concept of the present invention, such modifications or improvements should fall within the scope of protection claimed by the present invention.

Claims

1. A nozzle for biomass steam gasification, characterized in that: It includes a static pressure box (4) and a pre-combustion chamber (16), which are connected vertically to form a whole; The static pressure box (4) is equipped with a primary air duct (3), and a backfire prevention valve (15) is installed at the end of the static pressure box (4). The end of the primary air duct (3) passes through the backfire prevention valve (15) and terminates at the upper end of the pre-combustion chamber (16). The pre-combustion chamber (16) is shaped like a horn with its opening facing downwards. Multiple steam pipes (11) pass through the side wall of the pre-combustion chamber (16) from top to bottom. The lower end of the steam pipes (11) has a steam nozzle (12).

2. The nozzle for biomass steam gasification as described in claim 1, characterized in that: The pre-combustion chamber (16) is conical, and multiple steam pipes (11) are evenly distributed at equal angles around the pre-combustion chamber (16).

3. The nozzle for biomass steam vaporization as described in claim 2, characterized in that: The steam nozzle (12) is tilted at an angle toward the central axis of the pre-combustion chamber (16).

4. The nozzle for biomass steam gasification as described in claim 1, characterized in that: The upper end of the primary air duct (3) extends laterally out of the static pressure box (4) to form a primary air inlet (6); an ignition gun is provided in the middle of the primary air duct (3), and the end of the ignition gun extends out of the lower end of the primary air duct (3).

5. The nozzle for biomass steam vaporization as described in claim 1, characterized in that: The static pressure box (4) is provided with a biomass feed port (7) on its side wall, and a hydrocyclone (13) is coaxially arranged on the primary air duct (3). The position of the hydrocyclone (13) corresponds to the biomass feed port (7).

6. The nozzle for biomass steam vaporization as described in claim 1, characterized in that: The upper part of the static pressure box (4) is also provided with a carrier gas supply port (1) for supplying air from top to bottom along the static pressure box (4) and sending biomass downward into the pre-combustion chamber (16).

7. The nozzle for biomass steam vaporization as described in claim 1, characterized in that: The gas medium of the carrier gas supply port (1) is nitrogen, and an electric air valve (2) is installed on the carrier gas supply port (1).

8. The nozzle for biomass steam vaporization as described in claim 1, characterized in that: The steam pipe (11) is equipped with electric air valves (9, 18, 17), and the steam pipe (11) is covered with an insulation layer (10).

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