Cement kiln head low-temperature waste heat recycling system

Abstract

The utility model discloses a cement kiln head low-temperature waste heat recycling system which comprises a condenser, and a water outlet of the condenser is connected with a condensate pump. The bottom of the AQC boiler is provided with a flue outlet, the flue outlet is connected with the condensate pump, and the side portion of the AQC boiler is further provided with an economizer. An annular heat exchanger is arranged on the outer side of the kiln body, the heat exchanger is provided with a water inlet and a water outlet, the water inlet of the heat exchanger is connected with the water outlet of the flue outlet, and the water outlet of the heat exchanger is connected with the deaerator. The utility model relates to the technical field of cement waste heat power generation, in particular to a cement kiln head low-temperature waste heat recycling system which can further save energy, reduce waste of heat resources and improve heat energy utilization efficiency through comprehensive utilization of cement kiln head waste gas and cement kiln barrel low-temperature waste heat resources. Recycling of kiln head waste gas waste heat resources and kiln body radiant heat is achieved, further, the recycled heat is directly used for heating condensed water, and the thermal deoxidizing effect is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of cement waste heat power generation, in particular to a cement kiln head low-temperature waste heat recycling system. Background Art

[0002] The kiln head AQC boiler of the cement kiln waste heat power generation system takes air from the medium temperature section of the cement kiln head grate cooler. The exhaust gas temperature is about 380℃, which belongs to medium and low temperature flue gas. The existing kiln head waste heat utilization has the following shortcomings:

[0003] First, after the kiln exhaust gas passes through the AQC boiler for heat exchange step by step, there is still low-temperature exhaust gas of about 100°C discharged, which cannot be fully recycled;

[0004] Second, when the cement kiln is operating normally, the temperature of the cement kiln cylinder is generally 200-300°C, and the radiant heat energy is not recycled.

[0005] Third, the waste heat power generation steam turbine system of cement kiln is not equipped with high and low pressure heaters for heat recovery cycle, so the deaerator adopts vacuum deaeration method, which leads to low feed water temperature and poor deaeration effect, affecting the service life of boiler pipes and reducing the overall thermal efficiency of waste heat power generation system. Utility Model Content

[0006] 1. Technical issues to be resolved

[0007] In view of the deficiencies of the prior art, the utility model provides a cement kiln head low-temperature waste heat recycling system, which solves the problem of low utilization rate of waste heat from cement kiln exhaust gas.

[0008] (II) Technical solution

[0009] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a cement kiln head low-temperature waste heat recycling system, comprising a condenser, the water outlet of the condenser is connected to a condensate pump.

[0010] AQC boiler, a flue outlet is provided at the bottom of the AQC boiler, the flue outlet is connected to a condensate pump, and an economizer is also provided on the side of the AQC boiler.

[0011] The kiln body is provided with an annular heat exchanger on the outside of the kiln body. The heat exchanger has a water inlet and a water outlet. The water inlet is connected to the water outlet of the flue outlet, and the water outlet of the heat exchanger is connected to the deaerator.

[0012] The deaerator is connected to the economizer through the feed water pump.

[0013] As a further preference, a water inlet box and a water outlet box are respectively provided on the side of the flue outlet, the water inlet box and the water outlet box are connected through a heat exchange pipe, the water inlet box is connected to a condensate pump, and the water outlet box is connected to a heat exchanger.

[0014] As a further preference, the heat exchange pipe is a circuitous structure.

[0015] As further preferred, a steam interface is provided on the deaerator.

[0016] (III) Beneficial effects

[0017] The utility model provides a cement kiln head low-temperature waste heat recycling system. It has the following beneficial effects:

[0018] The cement kiln head low-temperature waste heat recycling system can further save energy, reduce heat resource waste, and improve thermal energy utilization efficiency through comprehensive utilization of cement kiln head exhaust gas and cement kiln cylinder low-temperature waste heat resources. It realizes the recycling of kiln head exhaust gas waste heat resources and kiln body radiation heat. Furthermore, the recovered heat is directly used to heat condensate water to achieve thermal deoxygenation effect, while increasing boiler feed water temperature and increasing waste heat power generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the utility model;

[0020] Figure 2 This is a cross-sectional view of the flue outlet structure of the utility model.

[0021] In the figure: 1. Condenser; 2. Condensate pump; 3. AQC boiler; 4. Flue outlet; 41. Water inlet tank; 42. Water outlet tank; 43. Heat exchange pipe; 5. Kiln body; 6. Heat exchanger; 7. Deaerator; 8. Water pump; 9. Economizer; 10. Steam interface. DETAILED DESCRIPTION

[0022] 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.

[0023] like Figure 1-2 As shown, the utility model provides a technical solution: a cement kiln head low-temperature waste heat recycling system, comprising a condenser 1, and a condensate pump 2 is connected to the water outlet of the condenser 1.

[0024] The AQC boiler 3 has a flue outlet 4 at its bottom, which is connected to the condensate pump 2 . An economizer 9 is also provided on the side of the AQC boiler 3 .

[0025] A water inlet box 41 and a water outlet box 42 are respectively provided on the side of the flue outlet 4. The water inlet box 41 and the water outlet box 42 are connected through a heat exchange pipe 43. The water inlet box 41 is connected to the condensate pump 2, and the water outlet box 42 is connected to the heat exchanger 6. The heat exchange pipe 43 is a circuitous structure, which increases the heat absorption area and improves the heat absorption efficiency.

[0026] The kiln body 5 has an annular heat exchanger 6 disposed outside the kiln body 5 . The heat exchanger 6 has a water inlet and a water outlet. The water inlet is connected to the water outlet of the flue outlet 4 . The water outlet of the heat exchanger 6 is connected to the deaerator 7 . The deaerator 7 is provided with a steam interface 10 .

[0027] The deaerator 7 is connected to the economizer 9 via a feed water pump 8 .

[0028] 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.

[0029] When in use, the condensate with a temperature of about 45°C formed after condensation in the condenser 1 is pressurized by the condensate pump 2 and enters the flue outlet 4 of the kiln head AQC boiler 3, and absorbs the residual heat of the boiler exhaust gas through the heat exchange pipe 43 in the flue outlet 4.

[0030] After that, the condensed water lowers the exhaust gas temperature of the kiln head AQC boiler 3, and then enters the heat exchanger 6 outside the kiln body 5, absorbs the radiation heat of the kiln body 5, and further increases the water temperature.

[0031] The condensed water after absorbing heat enters the deaerator 7. The deaerator 7 is provided with a steam interface 10, which utilizes a part of the low-pressure supplementary steam of the steam turbine to ensure that the water in the deaerator 7 boils and removes all oxygen.

[0032] The water temperature of the deaerator 7 is heated to 100°C to ensure the deoxygenation effect of the deaerator 7. The feed water pump 8 boosts the 100°C feed water in the deaerator 7 and sends it to the economizer 9 next to the AQC boiler 3 for use by the boilers at the head and tail of the kiln.

[0033] In summary, the cement kiln head low-temperature waste heat recycling system can further save energy, reduce the waste of heat resources, and improve the efficiency of thermal energy utilization through the comprehensive utilization of the cement kiln head exhaust gas and the low-temperature waste heat resources of the cement kiln cylinder. It realizes the recycling of the waste heat resources of the kiln head exhaust gas and the radiant heat of the kiln body. Furthermore, the recovered heat is directly used to heat the condensate water to achieve the thermal deoxygenation effect, while increasing the boiler feed water temperature and increasing the waste heat power generation.

[0034] 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.

[0035] 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 cement kiln head low temperature waste heat recycling system, characterized by: It comprises a condenser (1), the water outlet of the condenser (1) being connected to a condensate pump (2); An AQC boiler (3), wherein a flue outlet (4) is provided at the bottom of the AQC boiler (3), the flue outlet (4) is connected to a condensate pump (2), and an economizer (9) is also provided at the side of the AQC boiler (3); A kiln body (5), wherein an annular heat exchanger (6) is arranged outside the kiln body (5), and the heat exchanger (6) has a water inlet and a water outlet, wherein the water inlet is connected to the water outlet of the flue outlet (4), and the water outlet of the heat exchanger (6) is connected to the deaerator (7); The deaerator (7) is connected to the economizer (9) via a feed water pump (8).

2. A cement kiln head low temperature waste heat recycling system according to claim 1, characterized in that: A water inlet box (41) and a water outlet box (42) are respectively arranged on the side of the flue outlet (4); the water inlet box (41) and the water outlet box (42) are connected via a heat exchange pipe (43); the water inlet box (41) is connected to a condensate pump (2), and the water outlet box (42) is connected to a heat exchanger (6).

3. A cement kiln head low temperature waste heat recycling system according to claim 2, characterized in that: The heat exchange pipe (43) is a circuitous structure.

4. A cement kiln head low temperature waste heat recycling system according to claim 1, characterized in that: The deaerator (7) is provided with a steam interface (10).

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