CN219913041U

CN219913041U - Nozzle, input structure and decomposing furnace

Info

Publication number: CN219913041U
Application number: CN202320748943.7U
Authority: CN
Inventors: 王斌; 张宗见; 刘守信; 李志强; 张提提; 蔡盛强
Original assignee: Anhui Conch Construction Materials Design Institute Co Ltd; Anhui Conch Holdings Co Ltd
Current assignee: Anhui Conch Construction Materials Design Institute Co Ltd; Anhui Conch Holdings Co Ltd
Priority date: 2023-04-03
Filing date: 2023-04-03
Publication date: 2023-10-27
Anticipated expiration: 2033-04-03

Abstract

The utility model relates to the field of chemical industry, and particularly provides a nozzle, an input structure and a decomposing furnace, wherein the nozzle comprises an inlet end and an outlet end which are oppositely arranged, and the width and/or the length of the outlet end is larger than that of the inlet end; a flow chamber is formed between the inlet end and the outlet end, and a plurality of flow guide pieces are arranged in the flow chamber along the flow direction.

Description

Nozzle, input structure and decomposing furnace

Technical Field

The utility model relates to the field of chemical industry, in particular to a nozzle, an input structure and a decomposing furnace.

Background

The coal powder combustion technology of the cement production line firstly grinds coal into coal powder with certain fineness in a coal mill so as to reduce energy loss caused by heat absorption due to evaporation of redundant water in the coal powder combustion process and other adverse effects on the coal powder combustion process. The specific pulverized coal combustion method is a jet combustion method, which is to send a small amount of air with a certain momentum and carrying pulverized coal to a place where pulverized coal combustion is needed for combustion so as to release heat.

The fuel combustion in the decomposing furnace is a special flameless combustion (sometimes called as 'glow combustion') and the temperature in the decomposing furnace is much lower than the temperature in the combustion zone of the rotary kiln, and the pulverized coal combustion nozzle for the decomposing furnace is characterized in that the setting position is optimally matched with the position of the tertiary air entering the furnace and the position of the preheating raw material discharging point so as to ensure that the fuel can be rapidly sprayed into the hot tertiary air, thereby rapidly igniting and burning. At the same time, it is to be avoided that the preheated raw meal immediately flows into the fuel injection zone which has just ignited or has not yet ignited, as this would affect the ignition and combustion of the fuel. In addition, the injection position and the injection angle of the pulverized coal burner for the decomposing furnace are reasonably matched with the furnace inlet position and the furnace inlet angle of tertiary air, so that the furnace wall refractory lining of the decomposing furnace is prevented from being blown.

The principle of selecting the pulverized coal combustion nozzle of the decomposing furnace is as follows: the method comprises the following steps of (1) selecting a coal injection pipe according to the requirement of environmental protection; (2) Selecting a coal injection pipe according to specific conditions of raw materials and fuel; (3) And selecting a coal injection pipe according to the matching condition of the whole kiln system equipment. In short, the coal injection pipe for the decomposing furnace needs to be selected reasonably by comprehensive balance.

The control factor determining the coal powder combustion process is carbon, the combustion of the coal powder can be represented by the combustion of the carbon, and the combustion of the carbon belongs to heterogeneous reaction and is relatively complex.

The research results show that: oxygen diffuses to the carbon surface and is then adsorbed, and oxygen and carbon undergo a combustion reaction such as:

C + O2 → CO2 + 406957kJ/kmol(c) ①

2C + O2 → 2CO +123092kJ/kmol(c) ②

2CO + O2 → 2CO2 +283446kJ/kmol(c) ③

CO2 + C → 2CO - 162406kJ/kmol(c) ④

according to statistics, the cement industry is a third largest emission source of nitrogen oxides in the industrial industry of China, and is also an important factor for restricting green and environment-friendly sustainable development of the cement industry. The cement decomposing furnace mainly aims at decomposing cement raw materials, more than 85% of the raw materials are CaCO3, so that the raw materials decomposed in the decomposing furnace are mainly CaCO3, the CaCO3 is decomposed into CaO and CO2 at high temperature, the reaction is a typical endothermic reaction, and heat is mainly provided by burning coal dust entering the decomposing furnace.

In the control of the operation of the firing system we require avoiding CO production, mainly based on clinker quality and energy consumption considerations. The firing system produces CO, which is also responsible for insufficient combustion of the fuel due to improper operation or maintenance of the system, and possibly also the presence of carbonaceous organics in the raw meal (which is mainly indicated by the high CO concentration at the outlet of the preheater system). The CO content at the outlet of the preheater C1 can be regarded as heat loss brought away by incomplete combustion of the pulverized coal. The combustion heat of CO at normal temperature is 3018kcal/Nm3, and if the concentration of CO at the outlet of the preheater C1 is 1000PPM and the smoke amount of unit clinker is 1.35Nm 3/kg/cl, the heat consumption of the unit clinker is increased by 4.07 kcal/kg/cl; i.e. every 1000PPM increase in the pre-heater C1 outlet CO concentration, the clinker heat rate increases by 4.07kcal/kg. Cl. Assuming an actual clinker yield of 5000t/d, each 1000PPM rise of CO at the outlet of the preheater C1 is equivalent to 154kg/h increase of the amount of pulverized coal of the decomposing furnace (the lower calorific value of the pulverized coal is 5500 kcal/kg), calculated according to 195 ten thousand tons of clinker produced per year, in this case, the energy source is wasted greatly relative to the heat provided by increasing 1443 tons of pulverized coal for complete combustion.

Disclosure of Invention

The utility model aims to solve the problems that coal dust and oxygen in a decomposing furnace cannot be fully contacted, CO is generated and energy is wasted in the prior art, and provides a nozzle which can enlarge the dispersion area of the coal dust before entering the decomposing furnace, so that the coal dust and the oxygen can be fully contacted, the concentration of CO is reduced, and the energy is saved and the consumption is reduced in a production line.

In order to achieve the above object, the present utility model provides in one aspect a nozzle comprising an inlet end and an outlet end arranged opposite each other, the outlet end being larger in width and/or length than the inlet end; a flow chamber is formed between the inlet end and the outlet end, and a plurality of flow guide pieces are arranged in the flow chamber along the flow direction.

Preferably, the length of the outlet end is denoted as L, and the width is denoted as d, and the L/d takes a value between 1.5 and 2.5.

Preferably, the included angle between the line from the midpoint of the length of the inlet end to the end point of the length of the outlet end and the straight line where the length direction of the outlet end is located is denoted as θ, and the value of θ is between 45 ° and 55 °.

Preferably, the height of the nozzle is denoted H, h=l/2 tan (θ/180×pi).

Preferably, the flow guide is a flow guide vane.

Preferably, five flow guides are disposed in the flow chamber.

Preferably, five of said deflectors are equidistant everywhere in the horizontal direction.

In a second aspect, the present utility model provides an input structure, the input structure comprising a delivery conduit, the input structure further comprising the nozzle, the delivery conduit having one end connected to the inlet end.

Preferably, an arc-shaped transition part is further arranged between the conveying pipeline and the nozzle.

A third aspect of the utility model provides a decomposing furnace comprising the input structure.

Through the technical scheme, the coal powder is conveyed into the decomposing furnace from the outlet end with larger diffusion area by arranging the flow guide piece, so that the coal powder is more dispersed and fully contacted with oxygen after entering the decomposing furnace, the coal powder is fully and completely combusted in the decomposing furnace, the CO emission concentration of the outlet of the decomposing furnace is reduced, and the production line is energy-saving and consumption-reducing.

Drawings

FIG. 1 is a schematic view of the overall structure of the present utility model;

FIG. 2 is a cross-sectional view of the overall structure of the present utility model;

FIG. 3 is a front elevational view of the overall structure of the present utility model;

FIG. 4 is a schematic view of the outlet end of the nozzle of the present utility model;

fig. 5 is a top view of the overall structure of the present utility model.

Description of the reference numerals

A 100 nozzle;

101 an inlet end;

102 an outlet end;

103 a flow chamber;

104 a flow guide;

200 conveying pipelines;

300 arc transition;

the length of the L outlet end;

d width of the outlet end;

an included angle between a connecting line from the midpoint of the length of the theta inlet end to the end point of the length of the outlet end and a straight line where the length direction of the outlet end is positioned;

height of the H nozzle.

Detailed Description

In order to make the technical solutions and advantages of the embodiments of the present utility model more apparent, the following detailed description of exemplary embodiments of the present utility model will be given with reference to the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present utility model, not exhaustive of all embodiments. In addition, the embodiments of the present utility model and the features of the embodiments may be combined with each other without collision.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures. In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or those that are conventionally put in use of the product of the application, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific direction, be configured and operated in a specific direction, and thus should not be construed as limiting the present utility model.

In the prior art, coal dust is not fully combusted in a decomposing furnace, CO is easy to generate, and heat loss and great waste of energy are caused.

In view of the above problems, referring to fig. 1 to 5, the present utility model provides a nozzle 100, where the nozzle 100 includes an inlet end 101 and an outlet end 102 which are disposed opposite to each other, the outlet end 102 is wider and/or longer than the inlet end 101, and it can be understood that the outlet end 102 is formed by extending the inlet end 101 outwards, or that the cross-sectional area of the outlet end 102 is larger than that of the inlet end 101, a flow chamber 103 is formed between the inlet end 101 and the outlet end 102, and a plurality of flow guiding members 104 are disposed in the flow chamber 103 along the flow direction, so that pulverized coal can be uniformly dispersed along the flow guiding members 104 into a decomposing furnace.

It should be understood that the outlet 102 is wider and/or longer than the inlet 101, which means that the outlet 102 is wider than the inlet 101, the outlet 102 is longer than the inlet 101, or the outlet 102 is longer than the inlet 101, and the outlet 102 is wider and longer than the inlet 101, i.e. the diffusion area of the pulverized coal entering the decomposing furnace is enlarged, so that the subsequent diversion is performed in good cooperation with the diversion member 104.

It should be noted that the flow guide 104 mainly plays a role in dispersing pulverized coal, and may be in a blade shape, an arc shape or other structures capable of playing the same role.

The utility model provides a nozzle 100, and coal dust is conveyed into a decomposing furnace from an outlet end 102 with a larger diffusion area by arranging a flow guide piece 104, so that the coal dust is more dispersed and fully contacted with oxygen after entering the decomposing furnace, and the coal dust is fully and completely combusted in the decomposing furnace, so that the CO emission concentration at the outlet of the decomposing furnace is reduced, and the production line is energy-saving and consumption-reducing.

Considering the implementation of the overall structure, please refer to fig. 4, in some embodiments, the length of the outlet end 102 is denoted as L, and the width is denoted as d, so that L/d is between 1.5 and 2.5, and the nozzle 100 in this numerical range can more effectively disperse the pulverized coal.

In some embodiments, referring to fig. 3, the included angle between the line from the midpoint of the length of the inlet end 101 to the end point of the length of the outlet end 102 and the straight line along the length direction of the outlet end 102 is denoted as θ, where the θ is between 45 ° and 55 °, it is obvious that if the θ is too large, the nozzle 100 is too high, which wastes space, and if the θ is too small, the final opening of the nozzle 100 is too steep, which is not beneficial to pulverized coal input.

In some embodiments, please continue to refer to fig. 3, the height of the nozzle 100 is denoted as H, and h=l/2 tan (θ/180×pi), i.e., the height H of the nozzle 100 can be derived according to L and θ described above.

Specifically, the diameter D of the pulverized coal conveying pipeline 200 is determined according to the production line coal consumption Q1, the decomposing furnace coal dividing ratio a%, the number b of burners, the solid-gas ratio c and the wind speed V in the conveying pipeline 200, and the calculation formula is as follows: d = (4 × (Q1 × a%/b/c/V)/pi)/(0.5), the production line coal consumption, the decomposing furnace coal dividing ratio and the number of burners are determined according to the scale of the production line, the wind speed in the pipe is V=25-30 m/s, and the solid-gas ratio is c=4-6 kg/m≡3.

In view of the specific implementation of the flow guide 104, in some embodiments, the flow guide 104 is a flow guide vane, i.e., a piece of sheet-like material that may serve as a flow guide.

Referring to fig. 2 and fig. 3, in some embodiments, five flow guiding elements 104 are disposed in the flow chamber 103, and the five flow guiding elements 104 can properly disperse pulverized coal, so that the number of the flow guiding elements 104 is moderate, and the number of the flow guiding elements 104 can be selected by a person skilled in the art according to practical situations.

With continued reference to fig. 2 and 3, in some embodiments, five flow guiding elements 104 are equidistant everywhere in the horizontal direction, that is, five flow guiding elements 104 are equidistant at the outlet end 102, the inlet end 101 or anywhere of the nozzle 100, and the flow guiding elements 104 are equidistant at the inlet end 101, so that the pulverized coal can be ensured to be uniformly dispersed after entering the nozzle 100, and the flow guiding elements 104 are equidistant at the outlet end 102, so that the uniformly-separated pulverized coal can be ensured to be finally uniformly sent from the nozzle 100 to the decomposing furnace, so that the pulverized coal can be fully contacted with oxygen, thereby reducing the concentration of CO and avoiding energy waste.

In a second aspect of the present utility model, referring to fig. 1 to 3, the input structure includes a conveying pipe 200, and further includes a nozzle 100, where one end of the conveying pipe 200 is connected to the inlet end 101, it can be understood that the above-mentioned beneficial effects achieved by the nozzle 100 can be achieved, and therefore, the description thereof is omitted.

In some embodiments, considering that the wind speed is suddenly changed at the connection position of the conveying pipeline 200 and the nozzle 100, an arc-shaped transition part 300 is further arranged between the conveying pipeline 200 and the nozzle 100, the air flow carrying the pulverized coal can reach the effect of gradually changing the wind speed through the arc-shaped transition part 300, the pulverized coal can be timely and evenly dispersed, the pulverized coal is prevented from being concentrated at the central position, and finally the pulverized coal cannot be fully contacted with oxygen.

The third aspect of the present utility model provides a decomposing furnace, where the decomposing furnace includes an input structure, and it can be understood that the input structure can achieve the beneficial effects, and the decomposing furnace is not described herein.

The device provided by the utility model is applied to a certain 5000t/d production line of the company, the CO concentration at the outlet of the decomposing furnace is basically below 500PPm after the device is applied under the same condition, the CO emission concentration at the outlet of the decomposing furnace is about 3000PPm before the technical improvement, and the standard coal can be saved by 1.46 kg/cl according to the ton clinker waste gas amount of 1.35Nm < 3 >/kg/cl, so that the energy consumption for calcining the clinker is greatly reduced.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present utility model without departing from the spirit and scope of the utility model, and it is intended that the utility model encompass such modifications and variations as fall within the scope of the appended claims and their equivalents.

Claims

1. A nozzle (100), characterized in that the nozzle (100) comprises an inlet end (101) and an outlet end (102) arranged opposite each other, the outlet end (102) being larger in width and/or length than the inlet end (101);

a flow chamber (103) is formed between the inlet end (101) and the outlet end (102), and a plurality of flow guiding pieces (104) are arranged in the flow chamber (103) along the flow direction.

2. The nozzle (100) of claim 1, wherein the outlet end (102) has a length L and a width d, L/d being between 1.5 and 2.5.

3. The nozzle (100) according to claim 2, wherein the angle between the line from the midpoint of the length of the inlet end (101) to the end point of the length of the outlet end (102) and the straight line along the length direction of the outlet end (102) is defined as θ, and θ is between 45 ° and 55 °.

4. A nozzle (100) according to claim 3, characterized in that the height of the nozzle (100) is denoted H, H = L/2tan (θ/180 x pi).

5. The nozzle (100) of claim 1, wherein the flow guide (104) is a flow guide vane.

6. The nozzle (100) according to claim 1, wherein five of the flow guides (104) are provided within the flow chamber (103).

7. The nozzle (100) of claim 6, wherein five of the deflectors (104) are equidistant from each other in a horizontal direction.

8. An inlet arrangement comprising a delivery conduit (200), characterized in that the inlet arrangement further comprises a nozzle (100) according to any one of claims 1 to 7, the delivery conduit (200) being connected at one end to the inlet end (101).

9. The inlet arrangement according to claim 8, characterized in that an arcuate transition (300) is also provided between the conveying conduit (200) and the nozzle (100).

10. A decomposing furnace, characterized in that it comprises an input structure as claimed in claim 8 or 9.