阅读说明：本技术 一种生物质解耦燃烧装置及方法 (Biomass decoupling combustion device and method ) 是由 刘新华 郝江平 张楠 于 2020-05-26 设计创作，主要内容包括：本发明提供了一种生物质解耦燃烧装置及方法,所述装置包括由炉墙围成的炉体、炉体内纵向设置的隔墙、与隔墙下部相连的异形隔板、位于炉体内下部的通风炉排和后火墙；所述隔墙的一侧自上而下分别包括干燥区、热解气化区和半焦区,所述隔墙的另一侧自下而上分别包括还原燃烧区和燃尽区,半焦区和还原燃烧区的底部连通；异形隔板的中下部设有半开口,还原燃烧区设置调节风口。本发明在现有燃烧装置上增加异形隔板,控制半焦区料层的厚度及分布情况,并在尾部烟气划分还原燃烧区和燃尽区,控制还原燃烧区的还原性气氛条件,减少NO-(x)的生成,实现生物质的洁净燃烧；本发明可有效提高对燃烧过程的控制,增强对燃料的适应性,减小燃烧周期性的影响。(The invention provides a biomass decoupling combustion device and a biomass decoupling combustion method, wherein the device comprises a furnace body enclosed by furnace walls, partition walls longitudinally arranged in the furnace body, a special-shaped partition plate connected with the lower part of the partition walls, and a ventilation grate and a rear fire wall which are positioned at the lower part in the furnace body; one side of the partition wall respectively comprises a drying area, a pyrolysis gasification area and a semicoke area from top to bottom, the other side of the partition wall respectively comprises a reduction combustion area and a burnout area from bottom to top, and the bottoms of the semicoke area and the reduction combustion area are communicated; the middle lower part of the special-shaped partition plate is provided with a half opening, and the reduction combustion area is provided with an adjusting air port. The invention adds a special-shaped clapboard on the prior combustion device, controls the thickness and the distribution condition of a material layer in a semi-coke region, divides a reduction combustion region and a burnout region in tail flue gas, controls the reducing atmosphere condition of the reduction combustion region, and reduces NO x The clean combustion of the biomass is realized; the invention can effectively improve the control on the combustion process, enhance the adaptability to the fuel and reduce the influence of the combustion periodicity.)

1. A biomass decoupling combustion device is characterized by comprising a furnace body surrounded by furnace walls, partition walls longitudinally arranged in the furnace body, a special-shaped partition plate connected with the lower part of the partition walls, a ventilation grate and a rear fire wall;

the partition wall extends from the top end of the furnace body to the middle lower part of the furnace body, one side of the partition wall respectively comprises a drying area, a pyrolysis gasification area and a semicoke area from top to bottom, the lower part of the semicoke area is the ventilation grate, the other side of the partition wall respectively comprises a reduction combustion area and a burnout area from bottom to top, the lower part of the reduction combustion area is the rear fire wall, a gap is reserved between the lower part of the special-shaped partition plate and the ventilation grate to form a fire hole, and the bottoms of the semicoke area and the reduction combustion area are communicated;

the lower part of the special-shaped partition plate is provided with a half opening, and the edge of the half opening is positioned on the bottom edge of the special-shaped partition plate.

2. The decoupled combustion device of claim 1, wherein the furnace walls on two sides parallel to the partition wall are a front furnace wall and a rear furnace wall respectively, the furnace wall on the side of biomass feeding is the front furnace wall, and the rear furnace wall is positioned on the rear furnace wall;

preferably, the furnace body area below the ventilation grate and the rear fire wall is an ash area.

3. The decoupled combustion device of claim 1 or 2, wherein the half-opening of the profiled baffle is an area with a short upper edge and a long lower edge;

preferably, the shape of the half opening of the special-shaped partition plate is trapezoid or semicircular, preferably isosceles trapezoid;

preferably, the half-opening height of the special-shaped partition plate accounts for 1/5-4/5 of the total height of the special-shaped partition plate;

preferably, the half-opening is located in the middle of the profiled separator as seen in the length direction of the profiled separator;

preferably, the special-shaped partition board is fixedly connected with the partition wall, and preferably is connected in a hanging mode.

4. The decoupled combustion device of any of claims 1-3, wherein the ventilation grate is disposed in a downward inclination from the front furnace wall to the rear furnace wall, and extends to a lower end position of the rear furnace wall;

preferably, the inclination angle of the ventilation grate is 0-60 degrees of included angle with the horizontal direction, and preferably 5-30 degrees of included angle.

5. The decoupled combustion device of any of claims 1-4, wherein a thermal insulation layer is disposed around the reduction combustion zone, and the thermal insulation layer is disposed on the furnace wall and the side wall of the partition wall contacting the reduction combustion zone;

preferably, the lower furnace wall of the reduction combustion zone is provided with an adjusting tuyere, and the upper furnace wall is provided with a burnout tuyere.

6. A method for decoupled combustion of biomass using the device of any of claims 1-5, characterized in that the method comprises the steps of:

(1) after the biomass fuel enters the decoupling combustion device, the biomass fuel is sequentially subjected to drying, pyrolysis gasification and semicoke combustion in the downward movement process to generate pyrolysis gasification gas and semicoke combustion flue gas;

(2) the semicoke enters the lower part of the reduction combustion area along with the movement of the ventilation grate for further combustion, and the pyrolysis gasification coal gas and the semicoke combustion flue gas enter the reduction combustion area through a special-shaped partition plate and are mixed with air introduced through the ventilation grate for combustion to obtain mixed flue gas;

(3) and (3) mixing the mixed flue gas obtained in the step (2) with air for full combustion to obtain the burnout flue gas.

7. The method of decoupled combustion of claim 6, wherein the drying, pyrolysis gasification, and char combustion processes of step (1) are performed in a drying zone, a pyrolysis gasification zone, and a char zone, respectively;

preferably, the temperature of the drying process in the step (1) is 100-200 ℃;

preferably, the temperature of the pyrolysis gasification process in the step (1) is 300-900 ℃;

preferably, the temperature of the semicoke combustion process in the step (1) is 500-1100 ℃.

8. The method for decoupling combustion as claimed in claim 6 or 7, wherein the semicoke generated after the pyrolysis gasification in the step (1) falls onto a ventilation grate, and is mixed with air introduced into the ventilation grate to perform semicoke combustion;

preferably, the pyrolysis gasification gas of the step (1) has a composition comprising NH₃And reducing hydrocarbons.

9. The method of decoupling combustion as in any one of claims 6-8 wherein the ash generated after said char combustion of step (1) and step (2) enters an ash zone below an aeration grate;

preferably, the thickness of the semi-coke layer passing through the semi-opening of the special-shaped partition plate is larger than that of the semi-coke layer passing through the areas on two sides of the semi-opening of the special-shaped partition plate;

preferably, the combustion temperature of the reduction combustion zone in the step (2) is 900-1100 ℃;

preferably, air is introduced from the regulating tuyere to support combustion during the mixed combustion in the step (2);

preferably, the excess air coefficient of the reduction combustion zone in the step (2) is 0.6-0.95.

10. The method for decoupling combustion as claimed in any one of claims 6 to 9, wherein the temperature of the combustion in step (3) is 1000 to 1300 ℃;

preferably, the air in the step (3) is introduced from an over-fire air port arranged on the furnace wall;

preferably, the excess air coefficient during combustion after air is introduced in the step (3) is 1.05-2.

Technical Field

The invention belongs to the technical field of fuel combustion, and relates to a biomass decoupling combustion device and method.

Background

With the gradual depletion of fossil energy and the continuous enhancement of environmental protection requirements, the development and utilization of renewable energy are concerned, biomass is taken as renewable energy, the stored energy is rich, the development and utilization of the renewable energy can effectively slow down the greenhouse effect, but the biomass is difficult to store and transport due to small volume density and large stacking volume, the volatile content is high, the combustion is asynchronous, and the situation of black smoke emission is serious. The existing combustion equipment is low in combustion efficiency, and the combustion utilization of biomass is restricted.

In the traditional middle-size and small-size decoupling combustion device, NO produced in the combustion process can be reduced through the reducibility of the pyrolysis zone and the semicoke zone_xParticularly, the form, the size and the ventilation volume of the semi-coke area greatly influence the performance of the medium-small coal-fired decoupling combustion device; however, for various biomass fuels, because the volatile component content is high, the fixed carbon content is low, the semicoke area is small in volume and low in temperature, the influence on controlling the light volatile component to generate smoke black is small, and NO is inhibited in the combustion process_xIs unfavorable; meanwhile, the semicoke area is small in size, low in temperature and high in ventilation control requirement, otherwise, the combustion process is easy to be unstable, and the combustion temperature and the smoke emission components show obvious periodic changes.

CN 103471089A discloses a coal decoupling combustion device and a combustion method, the device comprises a furnace body and an air chamber positioned below the furnace body, the furnace body comprises an upper partition wall, a first lower partition wall and a second lower partition wall, the first lower partition wall and the second lower partition wall are positioned below the upper partition wall and are respectively arranged at the inner side and the outer side, a first fire grate is erected between the top end of the first lower partition wall at the inner side and the side wall of the furnace body, and a second fire grate is arranged between the bottoms of the first lower partition wall and the second lower partition wall; a gasification pyrolysis area and a semicoke area are formed between the upper part of the first grate and the upper partition wall, the semicoke area is positioned below the gasification pyrolysis area, and a coke area is formed between the first lower partition wall and the second lower partition wall; the device is mainly used for decoupling combustion of fire coal, is not suitable for combustion of biomass with high volatile components and high nitrogen content, and can generate NO_xHigh content of smoke.

CN 101270875A discloses a decoupling combustion device of biomass briquette and a combustion method thereof, the device comprises a vertical combustion furnace, a combustion chamber and a pyrolysis chamber, the bottoms of the combustion chamber and the pyrolysis chamber are communicated, a hopper is arranged above the pyrolysis chamber, a grate is arranged at the lower part of the combustion chamber, a screw conveyor is arranged at the lower part of the pyrolysis chamber, a flue gas interlayer is arranged on the outer side wall of the pyrolysis chamber, the flue gas interlayer is communicated with a flue gas channel arranged on a furnace body, an air channel is arranged below the grate, a flue gas guide plate is arranged in the combustion chamber, and the upper part of the flue gas guide plate is communicated with the flue gas interlayer; although the device carries out pyrolysis and combustion of biomass in different areas, the area division of the device does not clearly define a semi-coke area, and the semi-coke area and the combustion area belong to the same area, so that the temperature and the ventilation volume are difficult to accurately control, and the combustion efficiency of the biomass is influenced.

In summary, for the structural design of the biomass decoupling combustion device, a gas combustion area needs to be added to facilitate the generation of NO in the pyrolysis gas_xThe biomass is fully reduced, the pollutant discharge amount of biomass combustion is reduced, and the utilization efficiency of fuel is improved.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a biomass decoupling combustion device and a biomass decoupling combustion method.

In order to achieve the purpose, the invention adopts the following technical scheme:

on one hand, the invention provides a biomass decoupling combustion device which comprises a furnace body enclosed by furnace walls, partition walls longitudinally arranged in the furnace body, a special-shaped partition plate connected with the lower part of the partition walls, a ventilation grate and a rear fire wall, wherein the ventilation grate is arranged on the lower part of the partition walls;

the partition wall extends from the top end of the furnace body to the middle lower part of the furnace body, one side of the partition wall respectively comprises a drying area, a pyrolysis gasification area and a semicoke area from top to bottom, the lower part of the semicoke area is the ventilation grate, the other side of the partition wall respectively comprises a reduction combustion area and a burnout area from bottom to top, the lower part of the reduction combustion area is the rear fire wall, a gap is reserved between the lower part of the special-shaped partition plate and the ventilation grate to form a fire hole, and the bottoms of the semicoke area and the reduction combustion area are communicated;

the lower part of the special-shaped partition plate is provided with a half opening, and the edge of the half opening is positioned on the bottom edge of the special-shaped partition plate.

According to the invention, the decoupling combustion device is designed aiming at the composition characteristics of the biomass fuel, the reaction areas of the special-shaped partition plate and the reduction combustion area are added on the basis of the existing decoupling combustion device, the structural design of the special-shaped partition plate can enable pyrolysis gasification gas and semicoke combustion smoke to better enter the reduction combustion area, and the thickness of a semicoke material layer entering the reduction combustion area is controlled to be different, so that the air quantity entering the reduction combustion area from different positions is adjusted, the atmosphere condition of the reduction combustion area is conveniently controlled, and NO generated by the reaction of the reducing gas in the pyrolysis gasification gas_xReduction and reduction of NO in biomass combustion process_xThe discharge amount of (c); simultaneously, the structural design of the device can improve the stability of fuel combustion, reduce the influence of combustion periodicity, and improve the utilization efficiency of biomass.

The following technical solutions are preferred technical solutions of the present invention, but not limited to the technical solutions provided by the present invention, and technical objects and advantageous effects of the present invention can be better achieved and achieved by the following technical solutions.

As a preferable technical scheme of the invention, furnace walls on two sides parallel to the partition wall are respectively a front furnace wall and a rear furnace wall, the furnace wall on the biomass feeding side is the front furnace wall, and the rear fire wall is positioned on the rear furnace wall.

In the present invention, the designations of the front furnace wall and the rear furnace wall are made according to the position of addition of the fuel and the direction of movement during the reaction.

Preferably, the furnace body area below the ventilation grate and the rear fire wall is an ash area.

According to the distance from the ventilating grate to the top of the furnace and the total height of the partition wall and the special-shaped partition plate, the distance from the bottom of the special-shaped partition plate to the ventilating grate can be known, and the distance is the control of the thickness of the semi-coke material layer on the grate.

As a preferable technical scheme of the invention, the half opening of the special-shaped partition plate is an area with a short upper side and a long lower side.

Preferably, the shape of the half opening of the profiled baffle is trapezoid or semicircular, preferably isosceles trapezoid.

Preferably, the half-opening height of the profiled partition accounts for 1/5-4/5 of the total height of the profiled partition, such as 1/5, 3/10, 2/5, 1/2, 3/5, 7/10 or 4/5, but not limited to the recited values, and other values not recited in the range of the recited values are also applicable.

Preferably, the half-opening is located in the middle of the profiled baffle as seen in the length direction of the profiled baffle, and is symmetrical left and right about the central axis of the profiled baffle.

Preferably, an opening is additionally arranged above the half opening of the special-shaped partition plate.

In the invention, the lower part of the special-shaped partition board is provided with the semi-opening, so that gas generated in the pyrolysis gasification area and the semicoke area can enter the reduction combustion area from the semi-opening instead of entering only through a fire hole above the fire grate, thereby reducing the ventilation resistance of the fire grate; and through set up the opening again above half opening, can further strengthen the ventilation ability of dysmorphism baffle middle part upside, strengthen the adaptability to the fuel.

According to the invention, the openings at the middle lower part of the special-shaped partition plate are designed, so that the thicknesses of material layers between the special-shaped partition plate and the ventilation grate are different, the thickness of the material layer at the middle part is large, the ventilation quantity entering the reduction combustion area through the ventilation grate is small, and the quantity of coal gas generated in the pyrolysis gasification area entering the reduction combustion area through the half opening of the special-shaped partition plate or other openings at the upper part of the half opening is large; the thickness of the material layer of the two sides close to the furnace wall is smaller, the ventilation quantity entering the reduction combustion area through the ventilation grate is larger, and the quantity of the pyrolysis gasification coal gas entering the reduction combustion area through the lower part of the special-shaped partition plate is smaller.

Preferably, the special-shaped partition board is fixedly connected with the partition wall, and preferably is connected in a hanging mode.

According to the invention, the special-shaped partition plate and the partition wall are detachably connected, so that the special-shaped partition plate can be conveniently adjusted and replaced according to needs.

As a preferable technical scheme of the invention, the ventilation grate is obliquely arranged along the direction from the front furnace wall to the rear furnace wall and extends to the lower end position of the rear furnace wall.

Preferably, the inclination angle of the ventilation grate is 0 to 60 degrees, such as 0 degree, 5 degrees, 10 degrees, 15 degrees, 20 degrees, 25 degrees, 30 degrees, 40 degrees, 50 degrees or 60 degrees, with respect to the horizontal direction, but not limited to the enumerated values, and other non-enumerated values within the range of the enumerated values are also applicable, and preferably 5 to 30 degrees.

In the invention, the ventilation grate is obliquely arranged, so that the moving speed of the semicoke on the grate can be accelerated, the semicoke amount which can enter the reduction combustion area is properly increased, and the difficulty of air passing through the ventilation grate is reduced.

As a preferable technical scheme of the invention, a heat insulation layer is arranged around the reduction combustion zone and is positioned on the furnace wall and the side wall of the separation wall, which is in contact with the reduction combustion zone.

In the invention, the heat insulation layer is arranged in the reduction combustion zone, so that the reaction temperature of the reduction combustion zone can be ensured to be stabilized in a higher range, the reaction rate is accelerated, and the influence of the combustion periodicity on the reaction stability of the zone is reduced.

Preferably, the lower furnace wall of the reduction combustion zone is provided with an adjusting tuyere, and the upper furnace wall is provided with a burnout tuyere.

In the invention, the air entering the reduction combustion zone and the pyrolysis gasification coal gas are mixed and combusted in the reduction combustion zone, combustion-supporting air can be supplemented through the adjusting air port to control the whole combustion zone to combust in the optimal reducing atmosphere, most of fuel nitrogen in the generated flue gas is converted, but still contains a large amount of combustible substances such as unburned CO and the like, and excess air is introduced through the burnout air port to ensure that the residual combustible substances are burnout in the burnout zone.

In another aspect, the present invention provides a method for biomass decoupled combustion using the above apparatus, the method comprising the steps of:

(1) after the biomass fuel enters the decoupling combustion device, the biomass fuel is sequentially subjected to drying, pyrolysis gasification and semicoke combustion in the downward movement process to generate pyrolysis gasification gas and semicoke combustion flue gas;

(2) the semicoke enters the lower part of the reduction combustion area along with the movement of the ventilation grate for further combustion, and the pyrolysis gasification coal gas and the semicoke combustion flue gas enter the reduction combustion area through a special-shaped partition plate and are mixed with air introduced through the ventilation grate for combustion to obtain mixed flue gas;

(3) and (3) mixing the mixed flue gas obtained in the step (2) with air for full combustion to obtain the burnout flue gas.

As a preferred technical scheme of the invention, the drying, pyrolysis gasification and semicoke combustion processes in the step (1) are correspondingly carried out in a drying zone, a pyrolysis gasification zone and a semicoke zone.

In the invention, after being fed into a furnace body, biomass fuel firstly passes through a drying zone and then passes through a pyrolysis gasification zone to a lower semicoke zone, and then the drying, pyrolysis gasification and semicoke combustion processes are sequentially completed, and fixed ash slag generated by semicoke combustion enters an ash slag zone from a ventilation grate; and flue gas generated by burning the pyrolysis gasification coal gas and the semicoke enters the reduction combustion area from the lower part of the special-shaped partition plate.

Preferably, the temperature of the drying process in step (1) is 100 to 200 ℃, for example, 100 ℃, 120 ℃, 140 ℃, 150 ℃, 160 ℃, 180 ℃ or 200 ℃, but not limited to the recited values, and other values not recited in the range of the values are also applicable.

Preferably, the temperature of the pyrolysis gasification process in step (1) is 300 to 900 ℃, for example 300 ℃, 400 ℃, 500 ℃, 600 ℃, 700 ℃, 800 ℃ or 900 ℃, but is not limited to the recited values, and other values not recited in the range of the values are also applicable.

Preferably, the temperature of the semicoke burning process in the step (1) is 500 to 1100 ℃, for example, 500 ℃, 600 ℃, 700 ℃, 800 ℃, 900 ℃, 1000 ℃, or 1100 ℃, but is not limited to the recited values, and other values not recited in the range of the values are also applicable.

As a preferable technical scheme of the invention, the semicoke generated after pyrolysis and gasification in the step (1) falls onto a ventilation grate and is mixed with air introduced into the ventilation grate to carry out semicoke combustion.

Preferably, the pyrolysis gasification gas of the step (1) has a composition comprising NH₃And reducing hydrocarbons.

As a preferable technical scheme of the invention, ash generated after the semicoke is combusted in the step (1) and the step (2) enters an ash area below the ventilation grate.

Preferably, the thickness of the semi-coke layer passing through the semi-opening of the special-shaped partition plate is larger than that of the semi-coke layer passing through the areas on two sides of the semi-opening of the special-shaped partition plate.

According to the invention, at the lower half opening of the special-shaped partition plate, the material layer thickness and the semicoke amount are larger, the concentration of reducing atmosphere is larger, and the NO inhibition is facilitated_xGenerating; the part with smaller material layer thickness under the special-shaped partition plate has large air ventilation quantity, and simultaneously the oxygen concentration of the air is reduced and the temperature is increased after the air is combusted by the semicoke layer, so that the oxidant with uniform concentration and higher temperature can be provided for a reduction combustion area, and the pyrolysis gasification coal gas is combusted under the atmosphere of low oxygen and high temperature, thereby being beneficial to accelerating the nitrogen of the fuel to be N₂The transformation of (3).

According to the invention, due to the continuous change of the thickness of the material layer under the special-shaped partition plate, the upper and lower ventilation quantity and the continuous change of combustion components are always present in the area, so that the existence of a core combustion area of materials under discontinuous flow is ensured, sufficient combustion heat is provided, the furnace temperature is maintained, the combustion stability is increased, and the influence of the combustion periodicity is reduced.

Preferably, the combustion temperature in the reduction combustion zone in step (2) is 900 to 1100 ℃, for example 900 ℃, 925 ℃, 950 ℃, 980 ℃, 1000 ℃, 1020 ℃, 1050 ℃, 1080 ℃ or 1100 ℃, but is not limited to the recited values, and other values not recited in the range of the values are also applicable.

Preferably, air is introduced from the regulating tuyere to support combustion during the mixed combustion in the step (2).

Preferably, the excess air ratio of the reduction combustion zone in step (2) is 0.6 to 0.95, such as 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, or 0.95, but not limited to the recited values, and other values not recited in this range are also applicable.

In the invention, after combustion in the reduction combustion zone, the fuel nitrogen in the generated mixed smoke is mostly converted, but still contains a large amount of combustible substances such as unburned CO and the like, and the composition of the combustible substances comprises CO and N₂And CO₂Etc. alsoPossibly small amounts of NO still present_xAnd introducing excess air through the burnout air inlet to burn out the residual combustible substances in the burnout area.

In a preferred embodiment of the present invention, the temperature of the combustion in the step (3) is preferably 1000 to 1300 ℃, for example, 1000 ℃, 1030 ℃, 1050 ℃, 1080 ℃, 1100 ℃, 1120 ℃, 1150 ℃, 1180 ℃, 1200 ℃, 1250 ℃, or 1300 ℃, but is not limited to the above-mentioned values, and other values not mentioned in the above-mentioned range of values are also applicable.

Preferably, the air in the step (3) is introduced from an over-fire air port arranged on the furnace wall.

Preferably, the excess air ratio in the combustion after the air is introduced in the step (3) is 1.05-2, such as 1.05, 1.2, 1.4, 1.5, 1.6, 1.8 or 2, but not limited to the recited values, and other values not recited in the range of the values are also applicable.

Compared with the prior art, the invention has the following beneficial effects:

(1) the device of the invention can control the thickness and the distribution condition of the material layer entering the reduction combustion zone from the semicoke zone by adding the special-shaped partition plate on the basis of the existing decoupling combustion device and dividing the reduction combustion zone, thereby adjusting the air quantity entering the reduction combustion zone from different positions, being convenient to control the reducing atmosphere condition of the reduction combustion zone and reducing NO_xThe generation amount of the biomass fuel is reduced, the harmless combustion utilization of the biomass fuel is realized, and the combustion efficiency can reach more than 90%;

(2) the structural design of the device can effectively improve the control of the combustion process of the semi-coke, enhance the stability of the combustion process and the adaptability to the fuel, and reduce the influence of the combustion periodicity.

Drawings

Fig. 1 is a schematic structural diagram of a biomass decoupling combustion device provided in embodiment 1 of the present invention;

FIG. 2 is a schematic structural diagram of a profiled separator provided in example 1 of the present invention;

wherein, the furnace comprises 1-a front furnace wall, 2-a partition wall, 3-a rear furnace wall, 4-a special-shaped partition plate, 5-a ventilation grate, 6-a rear fire wall, 7-a drying zone, 8-a pyrolysis gasification zone, 9-a semi-coke zone, 10-an ash zone, 11-a reduction combustion zone, 12-an burnout zone, 13-an adjusting tuyere, 14-a burnout tuyere and 15-a heat insulation layer.

Detailed Description

In order to better illustrate the present invention and facilitate the understanding of the technical solutions of the present invention, the present invention is further described in detail below. However, the following examples are only simple examples of the present invention and do not represent or limit the scope of the present invention, which is defined by the claims.

The following are typical but non-limiting examples of the invention:

example 1:

the embodiment provides a biomass decoupling combustion device, the structural schematic diagram of which is shown in fig. 1, and the device comprises a furnace body enclosed by furnace walls, a partition wall 2 longitudinally arranged in the furnace body, a special-shaped partition plate 4 connected with the lower part of the partition wall 2, a ventilation grate 5 and a rear fire wall 6;

the partition wall 2 extends from the top end of the furnace body to the middle lower part of the furnace body to divide the furnace body into two parts, one side of the partition wall 2 respectively comprises a drying zone 7, a pyrolysis gasification zone 8 and a semicoke zone 9 from top to bottom, the lower part of the semicoke zone 9 is the ventilation grate 5, the other side of the partition wall 2 respectively comprises a reduction combustion zone 11 and a burnout zone 12 from bottom to top, the lower part of the reduction combustion zone 11 is the rear fire wall 6, a gap is reserved between the lower part of the special-shaped partition plate 4 and the ventilation grate 5 to form a fire hole, and the bottom of the semicoke zone 9 is communicated with the bottom of the reduction combustion zone 11;

the structural schematic diagram of the special-shaped partition plate 4 is shown in fig. 2, a half opening is arranged at the lower part of the special-shaped partition plate, and the edge of the half opening is positioned on the bottom edge of the special-shaped partition plate 4.

Furnace walls on two sides parallel to the partition wall 2 are respectively a front furnace wall 1 and a rear furnace wall 3, the furnace wall on one side of biomass feeding is the front furnace wall 1, and the rear fire wall 6 is positioned on the rear furnace wall 3.

The furnace body area below the ventilation grate 5 and the rear fire wall 6 is an ash area 10.

The half opening of the special-shaped partition plate 4 is an isosceles trapezoid with a short upper edge and a long lower edge, and the height of the half opening accounts for 2/5 of the total height of the special-shaped partition plate 4; the half opening is located in the middle of the profiled separator 4 as seen in the length direction of the profiled separator 4.

The special-shaped partition plate 4 is connected with the partition wall 2 in a hanging mode.

The ventilation grate 5 is arranged along the direction from the front furnace wall 1 to the rear furnace wall 3 in a downward inclined manner and extends to the lower end position of the rear fire wall 6; the inclination angle of the ventilation grate 5 is 10 degrees with the horizontal direction.

And a heat insulation layer 15 is arranged around the reduction combustion area 11, and the heat insulation layer 15 is positioned on the side wall of the furnace wall, the partition wall 2 and the reduction combustion area 11.

And an adjusting air port 13 is arranged on the lower furnace wall of the reduction combustion zone 11, and a burnout air port 14 is arranged on the upper furnace wall.

Example 2:

the embodiment provides a biomass decoupling combustion device, which comprises a furnace body enclosed by furnace walls, a partition wall 2 longitudinally arranged in the furnace body, a special-shaped partition plate 4 connected with the lower part of the partition wall 2, a ventilation grate 5 and a rear fire wall 6;

the partition wall 2 extends from the top end of the furnace body to the middle lower part of the furnace body to divide the furnace body into two parts, one side of the partition wall 2 respectively comprises a drying zone 7, a pyrolysis gasification zone 8 and a semicoke zone 9 from top to bottom, the lower part of the semicoke zone 9 is the ventilation grate 5, the other side of the partition wall 2 respectively comprises a reduction combustion zone 11 and a burnout zone 12 from bottom to top, the lower part of the reduction combustion zone 11 is the rear fire wall 6, a gap is reserved between the lower part of the special-shaped partition plate 4 and the ventilation grate 5 to form a fire hole, and the bottom of the semicoke zone 9 is communicated with the bottom of the reduction combustion zone 11;

the lower part of the special-shaped partition plate 4 is provided with a half opening, and the edge of the half opening is positioned on the bottom edge of the special-shaped partition plate 4.

Furnace walls on two sides parallel to the partition wall 2 are respectively a front furnace wall 1 and a rear furnace wall 3, the furnace wall on one side of biomass feeding is the front furnace wall 1, and the rear fire wall 6 is positioned on the rear furnace wall 3.

The furnace body area below the ventilation grate 5 and the rear fire wall 6 is an ash area 10.

The half opening of the special-shaped partition plate 4 is a semicircle with the diameter at the bottom edge, the height of the half opening is 4/5 of the total height of the special-shaped partition plate 4, and the half opening is positioned in the middle of the special-shaped partition plate 4 when viewed from the length direction of the special-shaped partition plate 4; an opening is additionally arranged above the half opening of the special-shaped partition plate 4.

The special-shaped partition plate 4 is connected with the partition wall 2 in a hanging mode.

The ventilation grate 5 is arranged along the direction from the front furnace wall 1 to the rear furnace wall 3 in a downward inclined manner and extends to the lower end position of the rear fire wall 6; the inclination angle of the ventilation grate 5 is 30 degrees with the horizontal direction.

And a heat insulation layer 15 is arranged around the reduction combustion area 11, and the heat insulation layer 15 is positioned on the side wall of the furnace wall, the partition wall 2 and the reduction combustion area 11.

And an adjusting air port 13 is arranged on the lower furnace wall of the reduction combustion zone 11, and a burnout air port 14 is arranged on the upper furnace wall.

Example 3:

the embodiment provides a biomass decoupling combustion method, which is implemented by using the device in embodiment 1, and comprises the following steps:

(1) after biomass fuel enters the decoupling combustion device, drying, pyrolysis gasification and semicoke combustion processes are sequentially carried out in the downward movement process, the temperature of the drying process is 150 ℃, the temperature of the pyrolysis gasification process is 550 ℃, the temperature of the semicoke combustion process is 800 ℃, pyrolysis gasification gas and semicoke combustion flue gas are generated, and the pyrolysis gasification gas comprises NH₃And reducing hydrocarbons; wherein, the semicoke generated after pyrolysis and gasification falls onto the ventilation grate 5 and is mixed with the air introduced into the ventilation grate 5 for semicoke combustion;

(2) the pyrolysis gasification coal gas and the semicoke combustion flue gas enter a reduction combustion area 11 through a special-shaped partition plate 4 and are mixed and combusted with air introduced through a ventilation grate 5, the semicoke enters the lower part of the reduction combustion area 11 along with the movement of the ventilation grate 5 to be further combusted, the thickness of a semicoke material layer passing through a half opening of the special-shaped partition plate 4 is larger than that of semicoke material layers passing through two side areas of the half opening of the special-shaped partition plate 4, the combustion temperature of the reduction combustion area is 1000 ℃, air is introduced from an adjusting air port 13 to support combustion during mixed combustion, and the excess air coefficient of the reduction combustion area 11 is 0.8, so that mixed flue gas is obtained;

(3) mixing the mixed flue gas obtained in the step (2) with air introduced into the overfire air port 14 for full combustion, wherein the mixed flue gas comprises CO and N₂And CO₂The combustion temperature is 1100 ℃, the excess air coefficient during combustion is 1.5, and the burnout flue gas is obtained.

In the embodiment, the biomass fuel is subjected to decoupling combustion by adopting the method, the combustion efficiency of the fuel reaches 92%, and NO in flue gas_xThe content meets the emission requirement.

Example 4:

the embodiment provides a biomass decoupling combustion method, which is implemented by using the device in embodiment 1, and comprises the following steps:

(1) after biomass fuel enters the decoupling combustion device, drying, pyrolysis gasification and semicoke combustion processes are sequentially carried out in the downward movement process, the temperature of the drying process is 200 ℃, the temperature of the pyrolysis gasification process is 800 ℃, the temperature of the semicoke combustion process is 1000 ℃, pyrolysis gasification gas and semicoke combustion flue gas are generated, and the pyrolysis gasification gas comprises NH₃And reducing hydrocarbons; wherein, the semicoke generated after pyrolysis and gasification falls onto the ventilation grate 5 and is mixed with the air introduced into the ventilation grate 5 for semicoke combustion;

(2) the pyrolysis gasification coal gas and the semicoke combustion flue gas enter a reduction combustion area 11 through a special-shaped partition plate 4 and are mixed and combusted with air introduced through a ventilation grate 5, the semicoke enters the lower part of the reduction combustion area 11 along with the movement of the ventilation grate 5 to be further combusted, the thickness of a semicoke material layer passing through a half opening of the special-shaped partition plate 4 is larger than that of semicoke material layers passing through two side areas of the half opening of the special-shaped partition plate 4, the combustion temperature of the reduction combustion area is 1100 ℃, air is introduced from an adjusting air port 13 to support combustion during mixed combustion, and the excess air coefficient of the reduction combustion area 11 is 0.9, so that mixed flue gas is obtained;

(3) the mixed flue gas obtained in the step (2) is communicated with an over-fire air inlet 14Mixing with air for full combustion, wherein the mixed flue gas comprises CO and N₂And CO₂The combustion temperature is 1300 ℃, the excess air coefficient during combustion is 1.1, and the burnout flue gas is obtained.

In the embodiment, the biomass fuel is subjected to decoupling combustion by adopting the method, the combustion efficiency of the fuel reaches 94 percent, and NO in flue gas_xThe content meets the emission requirement.

Example 5:

the embodiment provides a biomass decoupling combustion method, which is implemented by using the device in embodiment 2, and comprises the following steps:

(1) after biomass fuel enters the decoupling combustion device, drying, pyrolysis gasification and semicoke combustion processes are sequentially carried out in the downward movement process, the temperature of the drying process is 100 ℃, the temperature of the pyrolysis gasification process is 400 ℃, the temperature of the semicoke combustion process is 600 ℃, pyrolysis gasification gas and semicoke combustion flue gas are generated, and the pyrolysis gasification gas comprises NH₃And reducing hydrocarbons; wherein, the semicoke generated after pyrolysis and gasification falls onto the ventilation grate 5 and is mixed with the air introduced into the ventilation grate 5 for semicoke combustion;

(2) the pyrolysis gasification coal gas and the semicoke combustion flue gas enter a reduction combustion area 11 through a special-shaped partition plate 4 and are mixed and combusted with air introduced through a ventilation grate 5, the semicoke enters the lower part of the reduction combustion area 11 along with the movement of the ventilation grate 5 to be further combusted, the thickness of a semicoke material layer passing through a half opening of the special-shaped partition plate 4 is larger than that of semicoke material layers passing through two side areas of the half opening of the special-shaped partition plate 4, the combustion temperature of the reduction combustion area is 900 ℃, air is introduced from an adjusting air port 13 to support combustion during mixed combustion, and the excess air coefficient of the reduction combustion area 11 is 0.6, so that mixed flue gas is obtained;

(3) mixing the mixed flue gas obtained in the step (2) with air introduced into the overfire air port 14 for full combustion, wherein the mixed flue gas comprises CO and N₂And CO₂The combustion temperature is 1000 ℃, the excess air coefficient during combustion is 1.8, and the burnout flue gas is obtained.

This exampleIn the method, the biomass fuel is subjected to decoupling combustion, the combustion efficiency of the fuel reaches 90.5 percent, and NO in the flue gas is_xThe content meets the emission requirement.

Comparative example 1:

this comparative example provides a decoupled biomass combustion device whose structure is comparable to that of the device of example 1, except that: the device does not comprise the special-shaped partition plate 4, and the reduction combustion area 11 is not provided with the adjusting tuyere 13.

The device is adopted to carry out decoupling combustion of biomass, the thicknesses of semicoke material layers at different positions are basically the same when the semicoke moves along with the ventilation grate, resistance is large when pyrolysis gasification gas and semicoke combustion flue gas pass through a fire hole, air is difficult to enter, and atmosphere conditions during further combustion are difficult to control, so that the combustion efficiency of fuel is low, and NO in the flue gas is finally burnt out_xThe content is relatively high, and the emission can not reach the standard.

According to the embodiment and the comparative example, the device provided by the invention can control the thickness and the distribution condition of the material layer entering the reduction combustion zone from the semicoke zone by adding the special-shaped partition plate on the basis of the conventional decoupling combustion device and dividing the reduction combustion zone, so that the air quantity entering the reduction combustion zone from different positions is adjusted, the reducing atmosphere condition of the reduction combustion zone is conveniently controlled, and NO is reduced_xThe generation amount of the biomass fuel is reduced, the harmless combustion utilization of the biomass fuel is realized, and the combustion efficiency can reach more than 90%; the structural design of the device can effectively improve the control on the burning process of the semi-coke, enhance the stability of the burning process and the adaptability to the fuel and reduce the influence of the burning periodicity.

The applicant states that the present invention is illustrated by the detailed apparatus and method of the present invention through the above embodiments, but the present invention is not limited to the above detailed apparatus and method, i.e. it is not meant to imply that the present invention must be implemented by the above detailed apparatus and method. It will be apparent to those skilled in the art that any modifications to the present invention, equivalents of the means for substitution and addition of means for carrying out the invention, selection of specific means, etc., are within the scope and disclosure of the invention.