Biomass low-nitrogen combustion device
Technical Field
The utility model belongs to the technical field of biomass boiler system and specifically relates to a low nitrogen burner of living beings.
Background
The environmental problems caused by the increasing shortage of fossil fuels are becoming more severe, and biological energy is gaining attention as one of the alternative energy sources. Biomass has unique advantages: renewability, low pollution, wide distribution and rich total amount. The development and utilization of clean energy resources such as biomass energy and the like which are environment-friendly, renewable and rich in resources are the main strategic measures for solving the shortage of petroleum and coal in China, ensuring the national energy safety, protecting the ecological environment and improving the sustainable development capability of China.
The biological energy has high oxygen content, low sulfur content, low ash content and low emission concentration of sulfur oxides and nitrogen oxides after combustion. Although the content of N in biomass is less than that of coal, the content of N in biomass is on the same order of magnitude as that of coal due to the low calorific value of biomass, and the emission of nitrogen oxides from the combustion products of biomass is not insignificant.
At present, biomass fuel has two combustion modes in a heat supply system: one method adopts a biomass boiler to directly burn; the other is gasification post-combustion. The direct combustion causes the dust and NOx to be far beyond the standard due to the problem of the structure of the boiler body, so that the environmental-friendly emission requirement cannot be met; in addition, the gasification rate is low (generally lower than 60%), the NOx standard exceeding is serious, and improvement is urgently needed. At present, the combustion is mostly carried out by adopting a mode of gasification and then conveying, but the process is more complex and the investment is larger.
SUMMERY OF THE UTILITY MODEL
The utility model aims at the above not enough of prior art existence provides a living beings low-nitrogen combustion device that can effectively reduce NOx and discharge.
In order to achieve the above object, the present invention provides the following technical solutions: a biomass low-nitrogen combustion device comprises an air inlet pipe, a combustion outer cavity and a combustion inner cavity, wherein the air inlet pipe is provided with a first opening which is connected with the combustion outer cavity, and is provided with a second opening which is tangentially communicated with the combustion inner cavity; the combustion outer cavity is arranged in a jacket space outside the combustion inner cavity, and the tail end of the combustion outer cavity is connected with
A premixing cavity is arranged between the combustion outer cavity and the first opening, an air equalizing plate is arranged between the premixing cavity and the combustion outer cavity, and the premixing cavity is communicated with the first opening. The air equalizing plate is arranged to uniformly distribute the biomass gas in the combustion outer cavity, so that the combustion is more uniform, and the combustion efficiency is improved.
The air-equalizing plate may be a perforated plate.
And a guide block is arranged at the first opening.
The combustion outer cavity is provided with a first combustion air inlet, and the first combustion air inlet and the combustion outer cavity can be tangentially connected.
The combustion inner cavity is provided with a combustion-supporting air second inlet, and the combustion-supporting air second inlet is connected with the combustion inner cavity.
Compared with the prior art, the beneficial effects of the utility model are that: the combustion is sufficient, the emission of NOx can be effectively reduced, the emission of NOx is enabled to be below the national standard, and the emission of NOx can be controlled to be 80-150 mg.
Drawings
FIG. 1 is a schematic axial sectional view of a burner in a biomass low-nitrogen combustion device according to the present invention;
fig. 2 is a left side view schematic diagram of the combustor in the biomass low-nitrogen combustion device of the present invention.
Detailed Description
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.
A biomass low-nitrogen combustion device 2 is shown in figures 1 and 2 and comprises an air inlet pipe 21, a combustion outer cavity 25 and a combustion inner cavity 26, wherein the air inlet pipe 21 is provided with a first opening 22 which is connected with the combustion outer cavity 25, and part of biomass gas is input into the combustion outer cavity 25 to be combusted; the air inlet pipe 21 is provided with a second opening 27 which is tangentially communicated with the combustion inner cavity 26, and the rest biomass gas is input into the combustion inner cavity 26 for rotary combustion; therefore, the inner layer and the outer layer can be formed for staged combustion, double flame superposition is formed, the combustion is more sufficient, and the emission of NOx can be effectively reduced. The combustion outer cavity 25 is arranged in a jacket space formed by the combustion inner cavity 26 and the shell, and the tail end of the combustion outer cavity 25 is communicated with the tail end of the combustion inner cavity 26, so that the flames of the combustion of the inner layer and the outer layer are overlapped at an outlet, and the combustion efficiency is further improved. A premixing cavity 23 is arranged between the combustion outer cavity 25 and the first opening 22, an air equalizing plate 24 is arranged between the premixing cavity 23 and the combustion outer cavity 25, the premixing cavity 23 is communicated with the first opening 22, and biomass gas is uniformly distributed in the combustion outer cavity 25 through the arranged air equalizing plate 24, so that the combustion is more uniform, and the combustion efficiency is improved. The guide block 30 is arranged at the first opening 22 and used for uniformly overflowing the fuel in the air-equalizing plate 24 under the guidance of the guide block, so that the purpose of uniform distribution of the fuel is achieved. Wherein, the air-equalizing plate 24 can be a perforated plate. The combustion outer cavity 25 is provided with a first combustion-supporting air inlet 28, the first combustion-supporting air inlet 28 and the combustion outer cavity 25 can be tangentially connected, and the first combustion-supporting air inlet 28 introduces a mixed gas of high-temperature air and flue gas, so that the emission of nitrogen oxides can be effectively reduced, and the combustion efficiency can be improved. The combustion inner cavity 26 is provided with a second inlet 29 of combustion air, and the second inlet 29 of combustion air is connected with the combustion inner cavity 26. The high-temperature air is introduced into the combustion-supporting air second inlet 29, so that the combustion temperature can be effectively increased, and the combustion-supporting air second inlet is superposed with the flame of the combustion outer cavity 25, so that the stable ignition and the efficient combustion of the fuel gas can be effectively ensured.
The above description is only a preferred embodiment of the present invention, and the scope of the present invention should not be limited thereby, and all the simple equivalent changes and modifications made in the claims and the description of the new invention are also within the scope of the present invention.