Staged combustion cement kiln

Abstract

The utility model discloses a staged combustion cement kiln which comprises an installation platform, a feeding mechanism is arranged at the top end of the installation platform, a preheating mechanism is arranged at the bottom end of the feeding mechanism, a decomposing mechanism is arranged at the front end of the preheating mechanism, a feeding furnace is arranged at the bottom end of the decomposing mechanism, and a discharging mechanism is arranged at the bottom end of the feeding furnace. And the bottom of the front end of the feeding furnace is fixedly connected with a discharge port of which the outside is connected with the rotary kiln. The blast furnace is additionally arranged at the top end of the decomposition mechanism to increase the coal combustion decomposition space of the cement kiln, meanwhile, the two groups of air pipes are additionally arranged at the front end of the decomposition mechanism, and the blast furnace is lifted and two paths of air are fed, so that the combustion uniformity is improved, and the generation of nitrogen oxides is reduced; and the coal can be combusted in a staged manner after entering the decomposing furnace.

Description

TECHNICAL FIELD

[0001] The utility model relates to cement kiln technical field, concretely is a kind of cement kiln of staged combustion. BACKGROUND

[0002] Cement kiln is the core equipment in cement production, mainly used for calcining limestone, clay and other raw materials at high temperature to generate cement clinker, typical type includes rotary kiln and vertical kiln. Among them, the rotary kiln makes the material gradually complete decomposition, sintering and cooling at 1200-1450 ℃ high temperature through the inclined rotating cylinder, with the characteristics of large handling capacity, high thermal efficiency, good environmental protection performance, modern cement kiln generally integrates waste heat recovery, waste gas purification and waste co-processing technology, helps energy saving and emission reduction and resource recycling.

[0003] But the present stage cement kiln use has certain limitation, coal feeding too much can cause insufficient combustion, so that unburned coal powder is discharged with waste gas, causing fuel waste, and insufficient combustion causes insufficient kiln head temperature, affecting clinker firing quality. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a kind of cement kiln of staged combustion to solve the problems raised in the above background.

[0005] To achieve the above object, the utility model provides the following technical scheme: a kind of cement kiln of staged combustion, including installation platform, the top of the installation platform is provided with feeding mechanism, the bottom of the feeding mechanism is provided with preheating mechanism, the front end of the preheating mechanism is provided with decomposition mechanism, the bottom of the decomposition mechanism is provided with feeding furnace, the bottom of the front end of the feeding furnace is fixedly connected with the discharge port connected with rotary kiln outside.

[0006] Preferably, the feeding mechanism includes a first cyclone installed on the upper surface of the installation platform, the top of the first cyclone is fixedly connected with a volute, and the volute is provided with a first feeding port on one side outside.

[0007] Preferably, the preheating mechanism includes a second cyclone installed at the bottom of the first cyclone, a third cyclone installed at the bottom of the second cyclone, a fourth cyclone installed at the bottom of the third cyclone, and a fifth cyclone installed at the bottom of the fourth cyclone.

[0008] Preferably, the decomposition mechanism includes a decomposition furnace installed at the front end of the installation platform and communicated with the feeding furnace, an elevated furnace installed at the top of the decomposition furnace, and an air pipe installed at the front end of the decomposition furnace.

[0009] Preferably, the air pipe is provided with two paths to increase the air intake of the decomposition furnace.

[0010] Preferably, the feeding furnace is provided with a second feeding port at the middle of the front end, and six distribution pipes are arranged on the left and right sides of the feeding furnace, two of which are arranged at the bottom and four of which are arranged at the top.

[0011] Preferably, the first cyclone is sequentially provided with a refractory layer, a composite layer and a frame layer from outside to inside.

[0012] Preferably, the refractory layer is made of a chromium-nickel alloy coating, the composite layer is made of a silicon nitride ceramic and a silicon carbide composite material, and the frame layer is made of a high-strength alloy plate and is provided with a nano-silicate material at the connection with the composite layer.

[0013] Compared with the prior art, the utility model has the beneficial effects that:

[0014] 1. The cement kiln has the following beneficial effects: the heightening furnace is arranged at the top of the decomposition mechanism to increase the coal combustion and decomposition space of the cement kiln, two groups of air pipes are arranged at the front end of the decomposition mechanism, the heightening furnace is lifted and two air inlets are arranged to increase the combustion uniformity and reduce the generation of nitrogen oxides, a plurality of distribution pipes are arranged to enable the coal to be combusted in stages in the decomposition furnace, the combustion is controlled in detail and the structure is optimized, the environmental load is reduced and the economic benefit is improved, and the use effect of the cement kiln is improved.

[0015] 2. The cement kiln has the following beneficial effects: the refractory layer, the composite layer and the frame layer are arranged in the cyclone of the cement kiln, the frame layer provides sufficient mechanical strength while ensuring the overall strength of the cyclone, ensures that the cyclone is not deformed under the action of high-temperature and high-pressure gas flow, and cooperates with the nano-silicate material to greatly reduce heat loss and improve overall thermal energy utilization efficiency, the composite layer is arranged outside the frame layer to ensure thermal stability, improve compression resistance and overall hardness, and the refractory layer is arranged outside the composite layer to be used for a long time in a high-temperature environment of more than 1000 DEG C, prevent the outer surface from aging or peeling due to high temperature, and effectively ensure that the cyclone of the cement kiln has a long service life and excellent performance under harsh conditions such as high temperature, high corrosion and high wear. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a three-dimensional structure schematic view of the utility model;

[0017] Figure 2 It is a three-dimensional structure schematic view of the utility model Figure 1 It is an enlarged structure schematic view of A in the utility model;

[0018] Figure 3 It is a three-dimensional structure schematic view of the feeding mechanism of the utility model;

[0019] Figure 4The utility model discloses Figure 3 Amplification structural schematic diagram of middle B.

[0020] In the drawing: 1, installation platform, 2, feeding mechanism, 201, first cyclone, 202, volute, 203, first feeding port, 3, preheating mechanism, 301, second cyclone, 302, third cyclone, 303, fourth cyclone, 304, fifth cyclone, 4, decomposition mechanism, 401, decomposition furnace, 402, heightening furnace, 403, air pipe, 5, feeding furnace, 501, distribution pipe, 502, second feeding port, 503, discharge port, 6, refractory layer, 601, composite layer, 602, frame layer. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the utility model.

[0022] Please refer to Figures 1-4 The utility model provides two technical schemes:

[0023] Embodiment one, a cement kiln of grading combustion, including installation platform 1, the top of installation platform 1 is provided with feeding mechanism 2, the bottom of feeding mechanism 2 is provided with preheating mechanism 3, the front end of preheating mechanism 3 is provided with decomposition mechanism 4, the bottom of decomposition mechanism 4 is provided with feeding furnace 5, and the bottom of the front end of feeding furnace 5 is fixedly connected with the discharge port 503 connected with the rotary kiln outside.

[0024] The first cyclone 201 installed on the upper surface of the installation platform 1 is included in the feeding mechanism 2, the top of the first cyclone 201 is fixedly connected with the volute 202, one side outside the volute 202 is provided with the first feeding port 203, and the raw material can enter the inside of the volute 202 through the first feeding port 203 and preliminarily exchanges heat and separates with the high-temperature airflow in the first cyclone 201.

[0025] The second cyclone 301 installed at the bottom of the first cyclone 201 is included in the preheating mechanism 3, the bottom of the second cyclone 301 is installed with the third cyclone 302, the bottom of the third cyclone 302 is installed with the fourth cyclone 303, the bottom of the fourth cyclone 303 is installed with the fifth cyclone 304, and the material in the first cyclone 201 can exchange heat and separate through the second cyclone 301 and enter the next stage cyclone.

[0026] The decomposition mechanism 4 includes a mounting platform 1 installed in the middle position of the front end, a decomposition furnace 401 with a bottom end connected with the feeding furnace 5, a height increasing furnace 402 installed at the top end of the decomposition furnace 401, and a wind pipe 403 installed at the front end of the decomposition furnace 401. The wind pipe 403 is provided with two paths for increasing the air intake of the decomposition furnace 401. The height increasing furnace 402 can effectively increase the combustion space and increase the internal air intake in cooperation with the wind pipe 403 to improve the uniformity of subsequent combustion.

[0027] The feeding furnace 5 is provided with two split pipes 501 on the left and right sides. A second feeding port 502 is installed at the middle position of the front end of the feeding furnace 5. The split pipe 501 is provided with six, two split pipes 501 are arranged at the bottom of the left and right sides of the feeding furnace 5, and four split pipes 501 are arranged at the top of the left and right sides of the feeding furnace 5. The split pipe 501 is used for splitting the coal and realizing the staged feeding and combustion of the coal to improve the uniformity of the coal combustion.

[0028] The main difference between the second embodiment and the first embodiment is that:

[0029] A staged combustion cement kiln, the first cyclone 201 is provided with a refractory layer 6, a composite layer 601 and a frame layer 602 from outside to inside.

[0030] The refractory layer 6 adopts a chromium-nickel alloy coating, which has strong corrosion resistance to acid and alkali gases, prolongs the service life of the equipment, and can be used in a high temperature environment of more than 1400℃ for a long time to prevent the external surface from aging or peeling due to high temperature.

[0031] The composite layer 601 adopts a composite material of silicon nitride ceramic and silicon carbide. The silicon nitride ceramic has excellent thermal stability and can maintain its shape in a high temperature environment. It cooperates with the moderate thermal conductivity of silicon carbide to help maintain the temperature balance in the cyclone. It also has strong thermal shock resistance and can effectively resist cracks or breakage when the temperature changes dramatically.

[0032] The frame layer 602 adopts a high-strength alloy plate and is provided with nano-silicate material at the connection with the composite layer 601. The high-strength alloy plate provides sufficient mechanical strength to ensure that it does not deform under the action of high temperature and high pressure gas flow. It can also resist the impact of materials in high-speed gas flow, reduce damage to the equipment, and is provided with nano-silicate at the connection between the frame layer 602 and the composite layer 601, which can greatly reduce heat loss and improve overall thermal energy utilization efficiency. The contents not described in detail in the specification are all existing technologies known to those skilled in the art.

[0033] The embodiment of the application is used as follows: the main raw materials such as limestone, clay and iron ore are crushed to meet the requirements of particle size, then accurately proportioned and mixed, and then ground into raw meal, and the raw meal is fed from the top volute 202 of the feeding mechanism 2, and then sequentially passes through the cyclone of each stage of the preheating mechanism 3, and exchanges heat with the high-temperature gas stream rising from the decomposing furnace and the kiln, and is gradually preheated, and then the preheated raw meal enters the decomposing furnace 401, at this time, the material distribution pipe 501 can input the external coal into the interior of the decomposing furnace 401 in stages, and the air inlet amount in the decomposing furnace 401 is increased through the air pipe 403, and the increased height furnace 402 is additionally arranged at the top of the decomposing furnace 401 to increase the coal powder combustion reaction area, and the heat generated by the raw meal and the coal powder combustion is fully reacted, the carbonates are decomposed and denitrified. Then, the material falls into the discharge port 503, enters the rotary kiln through the flue chamber and is calcined into clinker.

[0034] The basic principle, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only preferred examples of the present application and are not intended to limit the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A cement kiln with staged combustion comprising a mounting platform (1), characterized in that: The top end of the mounting platform (1) is provided with a feeding mechanism (2), the bottom end of the feeding mechanism (2) is provided with a preheating mechanism (3), the front end of the preheating mechanism (3) is provided with a decomposition mechanism (4), the bottom end of the decomposition mechanism (4) is provided with a feeding furnace (5), and the bottom of the front end of the feeding furnace (5) is fixedly connected with a discharge port (503) connected with the rotary kiln.

2. A cement kiln with staged combustion according to claim 1, characterized in that: The feeding mechanism (2) comprises a first cyclone (201) mounted on the upper surface of the mounting platform (1), and the top end of the first cyclone (201) is fixedly connected with a volute (202), and one side of the volute (202) is provided with a first feeding port (203).

3. A cement kiln with staged combustion according to claim 1, characterized in that: The preheating mechanism (3) comprises a second cyclone (301) mounted at the bottom end of the first cyclone (201), a third cyclone (302) mounted at the bottom end of the second cyclone (301), a fourth cyclone (303) mounted at the bottom end of the third cyclone (302), and a fifth cyclone (304) mounted at the bottom end of the fourth cyclone (303).

4. A cement kiln with staged combustion as claimed in claim 1, wherein: The decomposition mechanism (4) comprises a decomposition furnace (401) mounted at the front end of the mounting platform (1) and communicated with the feeding furnace (5), an elevated furnace (402) mounted at the top end of the decomposition furnace (401), and an air pipe (403) mounted at the front end of the decomposition furnace (401).

5. A cement kiln with staged combustion according to claim 4, characterized in that: The air pipe (403) is provided with two air pipes for increasing the air volume of the decomposition furnace (401).

6. A cement kiln with staged combustion according to claim 1, characterized in that: The feeding furnace (5) is provided with a second feeding port (502) at the middle position of the front end, and the feeding furnace (5) is provided with six distribution pipes (501) on the left and right sides.

7. A cement kiln with staged combustion according to claim 2, characterized in that: The first cyclone (201) is provided with a refractory layer (6), a composite layer (601) and a frame layer (602) from outside to inside.

8. A cement kiln with staged combustion according to claim 7, characterized in that: The refractory layer (6) is made of chromium-nickel alloy coating, the composite layer (601) is made of silicon nitride ceramic and silicon carbide composite material, and the frame layer (602) is made of high-strength alloy plate and provided with nano silicate material at the connection with the composite layer (601).

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