Comprehensive treatment system for cement kiln tail ammonia escape

Abstract

The utility model discloses a cement kiln tail ammonia escape comprehensive treatment system which comprises a kiln tail dust collector, a tail exhaust fan is installed on the kiln tail dust collector, a first air inducing pipe and a second air inducing pipe are respectively installed at the position of an air outlet of the tail exhaust fan, and a first valve and a second valve are respectively arranged on the first air inducing pipe and the second air inducing pipe. The utility model relates to the technical field of cement environment-friendly treatment, in particular to a comprehensive treatment system for tail ammonia escape of a cement kiln, which can recycle kiln tail waste gas waste heat in a grate cooler, can reduce waste heat waste, does not need to additionally use an ammonia adsorbent, and has lower ammonia escape treatment cost.

Description

Technical Field

[0001] The utility model relates to the technical field of cement environmental protection treatment, in particular to a comprehensive treatment system for ammonia escape at the end of a cement kiln. Background Art

[0002] The cement kiln denitrification system generally adopts SNCR or SCR technology. Both technologies have the problem of ammonia escape. On the one hand, ammonia escape causes the denitrification cost to rise and is highly corrosive to related facilities such as flues. On the other hand, it will cause secondary atmospheric environmental pollution. At present, the main technical routes for the control of ammonia escape are: reducing ammonia emissions by optimizing the desulfurization and denitrification system and production process or equipment; using ammonia adsorbents; recycling ammonia, etc.

[0003] A system for capturing and reusing ammonia escape from a cement kiln [utility model] application number: CN202021686544.5. The system for capturing and reusing ammonia escape from a cement kiln provided by the utility model embodiment comprises: a multi-stage ammonia capture device, each stage of the ammonia capture device is provided with an ammonia adsorbent, and the ammonia adsorbent can adsorb ammonia molecules in the flue gas on the surface or inside of the ammonia adsorbent; a preheater, the preheater is connected to the multi-stage ammonia capture device, wherein the preheater receives the ammonia adsorbent after adsorbing ammonia molecules, and preheats it to achieve separation of ammonia and ammonia adsorbent, and then the ammonia is reused. The system for capturing and reusing ammonia escape from a cement kiln provided by the utility model embodiment improves the adsorption rate of ammonia by setting a multi-stage ammonia capture device, and solves the problem of excessive ammonia in the flue gas emission process. At the same time, ammonia is separated from ammonia adsorbent in the preheater, and then ammonia is reused to avoid waste of resources. Although this technology can reduce ammonia escape, there may be a problem of increased environmental protection costs due to the use of adsorbents. Utility Model Content

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the utility model provides a comprehensive treatment system for ammonia escape at the end of a cement kiln, which solves the problem of low ammonia treatment efficiency in the existing cement production process.

[0006] (II) Technical solution

[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a comprehensive treatment system for ammonia escape at the tail end of a cement kiln, comprising a dust collector at the tail end of the kiln, on which a tail exhaust fan is installed, and a first induced draft duct and a second induced draft duct are respectively installed at the air outlet position of the tail exhaust fan, and a first valve and a second valve are respectively arranged on the first induced draft duct and the second induced draft duct.

[0008] A Roots blower is installed at the air outlet of the first air duct.

[0009] The decomposition furnace is also included. A denitrification ammonia water spray gun is installed on the top of the decomposition furnace. The denitrification ammonia water spray gun is connected to a Roots blower.

[0010] The bottom of the decomposition furnace is connected to the kiln tail of the cement rotary kiln, the kiln head of the cement rotary kiln is connected to the grate cooler, a plurality of grate cooler cooling fans are arranged outside the grate cooler, and the air outlet of the second induced draft duct is connected to the inlet of the grate cooler cooling fan.

[0011] As a further preference, the air outlet of the tail exhaust fan is also connected to the chimney.

[0012] (III) Beneficial effects

[0013] The utility model provides a comprehensive treatment system for ammonia escape at the end of cement kiln. It has the following beneficial effects:

[0014] 1. The waste heat of kiln tail exhaust gas can be recycled in the grate cooler to reduce waste heat waste;

[0015] 2. The waste gas containing ammonia enters the decomposition furnace, which can reduce the consumption of ammonia water, and at the same time increase the temperature of the compressed air for the flow of ammonia water spray gun, reducing the disturbance of the decomposition furnace temperature;

[0016] 3. It forms a closed loop for part of the waste gas at the kiln tail, reduces the discharge of waste gas and various pollutants at the kiln tail, and is conducive to achieving ultra-low emissions of cement kiln pollutants;

[0017] 4. No additional ammonia adsorbent is required, and the cost of ammonia escape disposal is lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the utility model.

[0019] In the figure: 1. dust collector at the end of the kiln; 2. tail exhaust fan; 3. first induced draft duct; 4. second induced draft duct; 5. first valve; 6. second valve; 7. Roots blower; 8. decomposition furnace; 9. denitrification ammonia water spray gun; 10. cement rotary kiln; 11. grate cooler; 12. grate cooler cooling fan; 13. chimney. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] like Figure 1As shown, the utility model provides a technical solution: a comprehensive treatment system for ammonia escape at the tail of a cement kiln, comprising a kiln tail dust collector 1, on which a tail exhaust fan 2 is installed, and a first induced draft duct 3 and a second induced draft duct 4 are installed at the air outlet of the tail exhaust fan 2, and a first valve 5 and a second valve 6 are respectively arranged on the first induced draft duct 3 and the second induced draft duct 4, and the air intake volume can be controlled by the first valve 5 and the second valve 6 respectively.

[0022] The air outlet of the tail exhaust fan 2 is also communicated with the chimney 13 .

[0023] A Roots blower 7 is installed at the air outlet of the first air duct 3 .

[0024] The decomposition furnace 8 is also included. A denitrification ammonia water spray gun 9 is installed on the top of the decomposition furnace 8. The denitrification ammonia water spray gun 9 is connected to the Roots blower 7.

[0025] The bottom of the decomposition furnace 8 is connected to the kiln tail of the cement rotary kiln 10, and the kiln head of the cement rotary kiln 10 is connected to the grate cooler 11. A plurality of grate cooler cooling fans 12 are arranged outside the grate cooler 11, and the air outlet of the second induced draft duct 4 is connected to the inlet of the grate cooler cooling fan 12.

[0026] Meanwhile, the contents not described in detail in this specification belong to the prior art known to the professional and technical personnel in this field.

[0027] When in use, the waste gas containing ammonia components coming out of the kiln tail dust collector 1 enters the tail exhaust fan 2 and is then discharged through three channels. The first channel (traditional channel) is directly discharged into the chimney 13, and the second channel is led out through the first induced draft pipe 3 and compressed by the Roots blower 7 to form compressed air for use by the denitrification ammonia water spray gun 9. It enters the decomposition furnace 8 together with the ammonia water sprayed by the denitrification ammonia water spray gun 9. The beauty of this design is that the addition of ammonia-containing waste gas not only reduces the ammonia consumption of the spray gun, but also increases the temperature of the spray gun flow-aiding compressed air, thereby improving the thermal energy utilization rate.

[0028] The third channel is to introduce the ammonia-containing waste gas into the grate cooler cooling fan 12 through the second air duct 4, and then enter the grate cooler 11 for combustion, which can reduce the ammonia escape amount and the emission of other pollutants.

[0029] In summary, the system can realize the comprehensive recovery and utilization of ammonia in the kiln tail exhaust gas through multiple channels, reduce the emission of various pollutants at the kiln tail, and improve the utilization rate of exhaust gas thermal energy.

[0030] It should be noted that the electrical components appearing in this article are all connected to the external main controller and 220V or 380V mains electricity, and the main controller can be a conventional known device for controlling computers, etc. Its control principle, internal structure and control switch mode are all conventional means of the prior art, which are directly quoted here without further elaboration. In this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A comprehensive treatment system for ammonia escape at the end of a cement kiln, characterized by: The invention comprises a kiln tail dust collector (1), a tail exhaust fan (2) is installed on the kiln tail dust collector (1), a first air induced duct (3) and a second air induced duct (4) are installed at the air outlet of the tail exhaust fan (2), and a first valve (5) and a second valve (6) are arranged on the first air induced duct (3) and the second air induced duct (4); A Roots blower (7) is installed at the air outlet of the first air duct (3); It also includes a decomposition furnace (8), a denitrification ammonia water spray gun (9) is installed on the top of the decomposition furnace (8), and the denitrification ammonia water spray gun (9) is connected to the Roots blower (7); The bottom of the decomposition furnace (8) is connected to the kiln tail of the cement rotary kiln (10), the kiln head of the cement rotary kiln (10) is connected to the grate cooler (11), a plurality of groups of grate cooler cooling fans (12) are arranged outside the grate cooler (11), and the air outlet of the second air duct (4) is connected to the inlet of the grate cooler cooling fan (12).

2. A comprehensive treatment system for ammonia escape at the end of a cement kiln according to claim 1, characterized in that: The air outlet of the tail exhaust fan (2) is also connected to the chimney (13).

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