CN211316174U - Low-nitrogen combustor for biogas - Google Patents

Abstract

The utility model relates to a low-nitrogen burner for biogas, which belongs to the technical field of burners.A primary air pipe and a secondary air pipe are respectively communicated with an air supply main pipe, the primary air pipe is connected with a primary air regulating valve, and the secondary air pipe is connected with a secondary air regulating valve; the other end of the primary air pipe is communicated with the primary air chamber, a plurality of primary air branch pipes are connected to the primary air chamber in a penetrating manner, the other end of one primary air branch pipe positioned at the circle center is connected with a middle concentric jet air pipe in a penetrating manner, and the other ends of the plurality of primary air branch pipes which are distributed in an annular manner by taking the primary air branch pipe on the circle center as the circle center are all connected with annular jet air pipes in a penetrating manner; the primary air branch pipe is arranged in the gas chamber. The burner effectively solves the problems of poor combustion effect, complex structure, high manufacturing cost, poor mixing effect of fuel and air and the like of the burner in the prior art.

Description

Low-nitrogen combustor for biogas

Technical Field

The utility model relates to a combustor technical field, concretely relates to biogas's low nitrogen combustor.

Background

The energy is the basic element of human survival and development, and is the engine and the fundamental power of social and economic development. With the resource exhaustion and the environmental problems caused by the resource development and application of fossil energy, especially the dual pressure of economic growth and environmental protection is facing the national face, the supply capacity of clean fuel is related to the sustainable development of national economy, and a large amount of agricultural residues (straws, rice husks, peanut shells and the like) and forestry residues (logging residues, wood processing wastes, building wastes and the like) in various regions of China are remained, so that the resources are wasted, the environment is polluted, and the problems of energy shortage and environmental pollution are attempted to be solved by developing biomass waste gasification combustion equipment.

Sulfides and nitrogen oxides are main atmospheric pollutants and are important factors for triggering acid rain, haze and photochemical smog. Environmental standards in various places of China strictly limit the discharge amount of sulfides and nitrogen oxides. In the field of industrial and civil kilns, coal and petroleum products have traditionally been used as fuels. However, due to the limitation of the characteristics of the fuels, the difficulty in realizing the emission of low-sulfide and nitrogen oxides is very high, the emission of pollutants can reach the standard only by tail gas treatment, and the environmental protection cost is greatly increased.

In recent years, a gas burner using a biomass gasification gas as a fuel has been vigorously developed. Compared with natural gas burner, the biomass fuel gas has low sulfur content and CO₂Zero emission and low price. The biomass natural gas burner has the advantages of safety, reliability, convenient operation and low emission of sulfides and nitrogen oxides, can greatly reduce the emission of atmospheric pollutants and greenhouse gases by efficient and clean utilization, and is favorable for solving the environmental problem caused by fossil energy consumption.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to prior art's defect and not enough, provide a reasonable in design's biogas's low nitrogen combustor, it effectively solves among the prior art combustor combustion effect poor, the combustor structure is complicated, high in manufacturing cost and fuel and air mix the poor scheduling problem of effect.

In order to achieve the above purpose, the utility model adopts the following technical proposal: the biomass fuel gas combustion device comprises a main air supply pipe, a primary air pipe, a secondary air pipe, a primary air regulating valve, a secondary air regulating valve, a primary air chamber, a fuel gas chamber, a primary air branch pipe, a biomass fuel gas inlet, a middle concentric jet air pipe, an annular jet air pipe, a conical annular jet reflection conical tubular structure, a conical nozzle outlet cooling air pipe, an ignition electrode and a primary combustion chamber; the air supply main pipe is respectively communicated with a primary air pipe and a secondary air pipe, the primary air pipe is connected with a primary air regulating valve, and the secondary air pipe is connected with a secondary air regulating valve; the other end of the primary air pipe is communicated with the primary air chamber, a plurality of primary air branch pipes are connected to the primary air chamber in a penetrating manner, the other end of one primary air branch pipe positioned at the circle center is connected with a middle concentric jet air pipe in a penetrating manner, and the other ends of the plurality of primary air branch pipes which are distributed in an annular manner by taking the primary air branch pipe on the circle center as the circle center are all connected with annular jet air pipes in a penetrating manner; the primary air branch pipe is arranged in the gas chamber, the outlet ends of the middle concentric jet air pipe and the annular jet air pipe are arranged in the primary combustion chamber, the primary combustion chamber is communicated with the gas chamber, the outlet end of the primary combustion chamber is of a conical annular jet reflection cone tubular structure folded towards the circle center, a conical nozzle outlet cooling air pipe is sleeved outside the primary combustion chamber, a space between the conical nozzle outlet cooling air pipe and the outer wall of the primary combustion chamber forms a conical nozzle outlet cooling air chamber, the inlet end of the conical nozzle outlet cooling air chamber is communicated with the outlet end of the secondary air pipe, and the outlet end of the conical nozzle outlet cooling air chamber and the outlet end of the primary combustion chamber are communicated with the secondary combustion chamber; the ignition electrode penetrates through the conical nozzle outlet cooling air pipe and the primary combustion chamber; the side wall of the gas chamber is connected with a biomass gas inlet in a through way.

Furthermore, a flue gas backflow connecting pipe is connected to one side wall of the primary air chamber, which is opposite to the primary air branch pipe, in a penetrating manner, and an adjusting valve is connected to the flue gas backflow connecting pipe.

After the structure is adopted, the beneficial effects of the utility model are that:

1. combustible gas in the gas chamber is sucked into the primary combustion chamber for mixing through the turbulent flow injection effect of high-speed air in the primary air branch pipes 8, and part of the mixed gas is sprayed onto the conical annular jet flow reflection cone tubular structure under the injection effect of high-speed airflow to form an airflow refraction backflow area, so that better mixed gas is obtained;

2. the secondary air enters the conical nozzle outlet cooling air chamber 14 through the connection of the secondary air chamber and a secondary air adjusting valve, and has one function of cooling the primary combustion chamber, preventing the local temperature of the primary combustion chamber from being overhigh and improving the stability of combustion flame; the secondary air is preheated and sprayed out from the cooling air chamber at the outlet of the conical nozzle to enter a secondary combustion chamber or a furnace kiln to be fully mixed with mixed gas, so that the mixing uniformity is improved, the combustion reaction is promoted, and the secondary combustion is fully completed.

Description of the drawings:

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

Fig. 2 is a sectional view taken along line a-a in fig. 1.

Description of reference numerals:

the biomass fuel gas burner comprises a main air supply pipe 1, a primary air pipe 2, a secondary air pipe 3, a primary air regulating valve 4, a secondary air regulating valve 5, a primary air chamber 6, a fuel gas chamber 7, a primary air branch pipe 8, a biomass fuel gas inlet 9, a middle concentric jet air pipe 10, an annular jet air pipe 11, a conical annular jet flow reflection cone tubular structure 12, a conical nozzle outlet cooling air pipe 13, a conical nozzle outlet cooling air chamber 14, a secondary combustion chamber 15, an ignition electrode 16, a flue gas backflow connecting pipe 17, a regulating valve 18 and a primary combustion chamber 19.

The specific implementation mode is as follows:

the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1 and fig. 2, the following technical solutions are adopted in the present embodiment: the biomass fuel gas burner comprises a main air supply pipe 1, a primary air pipe 2, a secondary air pipe 3, a primary air regulating valve 4, a secondary air regulating valve 5, a primary air chamber 6, a fuel gas chamber 7, a primary air branch pipe 8, a biomass fuel gas inlet 9, a middle concentric jet air pipe 10, an annular jet air pipe 11, a conical annular jet flow reflection cone tubular structure 12, a conical nozzle outlet cooling air pipe 13, an ignition electrode 16 and a primary combustion chamber 19; the air supply main pipe 1 is respectively communicated with a primary air pipe 2 and a secondary air pipe 3, the primary air pipe 2 is connected with a primary air regulating valve 4, and the secondary air pipe 3 is connected with a secondary air regulating valve 5; the other end of the primary air pipe 2 is communicated with a primary air chamber 6, a plurality of primary air branch pipes 8 are connected to the primary air chamber 6 in a penetrating way, the other end of one primary air branch pipe 8 positioned at the circle center position is connected with a middle concentric jet air pipe 10 in a penetrating way, and the other ends of the plurality of primary air branch pipes 8 which are distributed in an annular shape by taking the primary air branch pipe 8 at the circle center as the circle center are all connected with annular jet air pipes 11 in a penetrating way; the primary air branch pipe 8 is arranged in the gas chamber 7, the outlet ends of the middle concentric jet flow air pipe 10 and the annular jet flow air pipe 11 are arranged in the primary combustion chamber 19, the primary combustion chamber 19 is communicated with the gas chamber 7, the outlet end of the primary combustion chamber 19 is a conical annular jet flow reflection cone tubular structure 12 folded towards the circle center, a conical nozzle outlet cooling air pipe 13 is sleeved outside the primary combustion chamber 19, the outer annular wall of the conical nozzle outlet cooling air pipe 13 is fixedly connected with the outer wall of the inlet end of the secondary combustion chamber 15 through a connecting sheet, and a conical nozzle outlet cooling air chamber 14 is formed by the space between the conical nozzle outlet cooling air pipe 13 and the outer wall of the primary combustion chamber 19, the inlet end of the conical nozzle outlet cooling air chamber 14 is communicated with the outlet end of the secondary air pipe 3, and the outlet end of the conical nozzle outlet cooling air chamber 14 and the outlet end of the primary combustion chamber 19 are communicated with the secondary combustion chamber 15; the ignition electrode 16 penetrates through the conical nozzle outlet cooling air pipe 13 and the primary combustion chamber 19; the side wall of the gas chamber 7 is connected with a biomass gas inlet 9 in a through way; a flue gas backflow connecting pipe 17 is connected through one side wall of the primary air chamber 6 opposite to the primary air branch pipe 8, and an adjusting valve 18 is connected on the flue gas backflow connecting pipe 17.

The working principle of the specific embodiment is as follows: according to the characteristics of biomass air gasification combustible gas: the content of nitrogen in the produced gas is higher and accounts for about 50 percent, the heat value of the gas is lower, and the main combustible components comprise carbon monoxide, hydrogen and a small amount of methane; the device divides air into two stages, namely a primary air pipe 2 is divided into a plurality of primary air branch pipes 8, the air is ejected by a middle concentric jet air pipe 10 and an annular jet air pipe 11 through the turbulent flow injection effect of high-pressure air to form concentric injection flow and annular injection flow, biomass natural gas is divided into a plurality of strands of injection flows to enter a primary combustion chamber 19, an annular backflow area is formed near a nozzle of a fire nozzle of the primary combustion chamber 19, and due to the rubbing friction effect of turbulent vortex groups, the injection flow presents a circumferential velocity component, so that the normal component stress of the side surface is added, and the entrainment mixing effect is very strong; in addition, the outer ring of the annular jet air pipe 11 injects jet flow to the inner wall of the conical annular jet flow reflection cone tubular structure 12 to form air flow convolution so as to further enhance the full mixing of air and combustible gas; the secondary air enters the conical nozzle outlet cooling air chamber 14 from the secondary air pipe 3 and flows through the conical nozzle outlet cooling air chamber 14, the temperature of the head of a nozzle can be reduced, secondary air distribution can be preheated, the inner ring of the middle concentric jet air pipe 10 and the inner ring of the annular jet air pipe 11 can inject and jet mixed gas to be intensively mixed with secondary heating air outside the nozzle, the mixing effect of air and combustible gas is accelerated, the mixing uniformity is improved, the combustion reaction is promoted, the generation of local high temperature is prevented, flame has uniform lower temperature level, and strong mixing can be completely combusted under the lower excess air coefficient.

After adopting above-mentioned structure, this embodiment's beneficial effect is:

1. combustible gas in the gas chamber 7 is sucked into the primary combustion chamber for mixing through the turbulent flow injection effect of high-speed air in the primary air branch pipes 8, and part of the mixed gas is sprayed onto the conical annular jet flow reflection cone tubular structure 12 under the injection effect of high-speed airflow to form an airflow refraction reflux area, so that better mixed gas is obtained;

2. the secondary air enters the conical nozzle outlet cooling air chamber 14 through the connection of the secondary air chamber 3 and the secondary air adjusting valve 5, and has one function of cooling the primary combustion chamber 19, preventing the local temperature of the primary combustion chamber 19 from being overhigh and improving the stability of combustion flame; the secondary air is sprayed out through the preheating of the conical nozzle outlet cooling air chamber 14 and enters the secondary combustion chamber 15 or the furnace kiln to be fully mixed with mixed gas, so that the mixing uniformity is improved, the combustion reaction is promoted, and the secondary combustion is fully completed;

3. the rear end of the primary air chamber 6 is connected with a flue gas backflow connecting pipe 17, and the flue gas is reintroduced into the combustion area by utilizing the air injection effect or an external fan, so that the oxygen concentration and the combustion temperature of the combustion area are reduced, the generation of local high temperature is prevented, the retention time of the flue gas in the high temperature area is shortened, and the generation of nitrogen oxides is inhibited.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments or portions thereof without departing from the spirit and scope of the invention.

Claims (2)

1. A low-nitrogen combustor for biogas, characterized in that: the biomass fuel gas combustion system comprises a main air supply pipe (1), a primary air pipe (2), a secondary air pipe (3), a primary air regulating valve (4), a secondary air regulating valve (5), a primary air chamber (6), a fuel gas chamber (7), a primary air branch pipe (8), a biomass fuel gas inlet (9), a middle concentric jet air pipe (10), an annular jet air pipe (11), a conical annular jet reflection cone tubular structure (12), a conical nozzle outlet cooling air pipe (13), an ignition electrode (16) and a primary combustion chamber (19); a primary air pipe (2) and a secondary air pipe (3) are respectively communicated with the air supply main pipe (1), the primary air pipe (2) is connected with a primary air regulating valve (4), and the secondary air pipe (3) is connected with a secondary air regulating valve (5); the other end of the primary air pipe (2) is communicated with a primary air chamber (6), a plurality of primary air branch pipes (8) are connected to the primary air chamber (6) in a penetrating way, the other end of one primary air branch pipe (8) positioned at the circle center position is connected with a middle concentric jet air pipe (10) in a penetrating way, and the other ends of the plurality of primary air branch pipes (8) which are distributed annularly by taking the primary air branch pipe (8) at the circle center as the circle center are all connected with an annular jet air pipe (11) in a penetrating way; the primary air branch pipe (8) is arranged in the gas chamber (7), the outlet ends of the middle concentric jet air pipe (10) and the annular jet air pipe (11) are arranged in the primary combustion chamber (19), the primary combustion chamber (19) is communicated with the gas chamber (7), the outlet end of the primary combustion chamber (19) is a conical annular jet flow reflection cone-shaped structure (12) folded towards the circle center, a conical nozzle outlet cooling air pipe (13) is sleeved outside the primary combustion chamber (19), and a space between the conical nozzle outlet cooling air pipe (13) and the outer wall of the primary combustion chamber (19) forms a conical nozzle outlet cooling air chamber (14), the inlet end of the conical nozzle outlet cooling air chamber (14) is communicated with the outlet end of the secondary air pipe (3), and the outlet end of the conical nozzle outlet cooling air chamber (14) and the outlet end of the primary combustion chamber (19) are communicated with the secondary combustion chamber (15); the ignition electrode (16) penetrates through the conical nozzle outlet cooling air pipe (13) and the primary combustion chamber (19); the side wall of the gas chamber (7) is connected with a biomass gas inlet (9) in a through way.

2. A biogas low-nitrogen burner as claimed in claim 1, wherein: one side wall of the primary air chamber (6) opposite to the primary air branch pipe (8) is connected with a smoke backflow connecting pipe (17) in a penetrating way, and the smoke backflow connecting pipe (17) is connected with an adjusting valve (18).

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