Device for cooling, dedusting and waste heat utilization of kiln head of rotary kiln

Abstract

The utility model relates to a device for cooling, dedusting and waste heat utilization of a kiln head of a rotary kiln. The device comprises a kiln head cooling structure, a deduster, a dedusting fan, a chimney, a combustion fan and a regulating valve, the kiln head cooling structure, the dust remover, the dust removal fan and the chimney are sequentially connected through a pipeline; an outlet of the combustion fan is connected with the combustor through a pipeline, an inlet of the combustion fan is connected with the three-way pipe, one connector of the three-way pipe is connected with the adjusting valve and then communicated with the atmosphere, and the other connector of the three-way pipe is connected with an outlet of the dust removal fan. The method has the advantages that stable operation of the rotary kiln system under special conditions of failure, kiln drying, low yield and the like is guaranteed. Dust collection air is used for cooling a kiln head metal structure, one dust removal fan is used, kiln head cooling fans (generally two centrifugal fans) and corresponding pipelines are saved, the occupied area is saved, and the one-time investment and maintenance cost of equipment are reduced.

Description

Technical Field

[0001] The utility model belongs to the field of rotary kilns, and in particular relates to a device for cooling, removing dust and utilizing waste heat of a rotary kiln head. Background Art

[0002] The kiln head of the rotary kiln goes deep into the kiln head cover, and the metal parts on the kiln head are exposed to high temperature environment, and the ambient temperature can reach 600-700℃. The kiln head is washed by high temperature materials for a long time, and the metal structure of the kiln head is prone to burnout, causing deformation, cracking, and falling of the metal structure of the kiln head. At present, 1 to 2 fans (called kiln head cooling fans) are generally required in engineering to provide cold air to cool the kiln mouth metal parts. With the development trend of large-scale rotary kilns, kiln head cooling fans with larger flow rates are required. In engineering, the cooling of the kiln head of a rotary kiln with a diameter of 4.9m requires 2 fans with a flow rate of 10,000m 3 The hot air temperature after cooling the rotary kiln head can reach 100℃, which is usually discharged as a waste gas and not recycled.

[0003] The rotary kiln is a rotating equipment. A certain sealing structure is usually set between the kiln head and the kiln head hood to prevent the leakage of materials carried by the air in the kiln. In fact, it is still difficult to completely avoid it when the operating conditions are bad. With the further improvement of environmental protection requirements, more and more companies require the collection and treatment of dust discharged from the kiln mouth. For example, in a certain lime project, the company requires that the kiln head and the kiln head hood be completely closed, and dust is not allowed to leak out. In the design, a dust collection hood is added to the original sealing structure, and a dust removal fan and dust collector are required to deal with the dust here, which increases the investment. As in the prior art, patent application number CN201922272402.8 discloses a cooling and dust removal device at the end of a calcining rotary kiln. Summary of the invention

[0004] The utility model aims to provide a device for cooling, dust removal and waste heat utilization of a rotary kiln head, which utilizes dust collecting wind to simultaneously realize cooling of the kiln mouth and collection of overflowing dust, and can utilize the waste heat of hot air after heat exchange at the kiln head.

[0005] To achieve the above purpose, the utility model is implemented through the following technical solutions:

[0006] A device for cooling, dust removal and waste heat utilization of a rotary kiln head, comprising a kiln head cooling structure, a dust collector, a dust removal fan, a chimney, a combustion-supporting fan and a regulating valve;

[0007] The kiln head cooling structure, dust collector, dust removal fan and chimney are connected in sequence through pipelines; the outlet of the combustion-supporting fan is connected to the burner through a pipeline, and the inlet of the combustion-supporting fan is connected to a three-way pipe. One interface of the three-way pipe is connected to the atmosphere after connecting to the regulating valve, and the other interface is connected to the outlet of the dust removal fan.

[0008] The kiln head cooling structure comprises a cooling air duct, an air collecting hood, a kiln head hood and a sealing structure; the cooling air duct is a two-layer structure, the first layer structure is close to the kiln head cylinder, the first layer structure is an air inlet duct, the left end is open, and the right end is connected to the rotary kiln; the second layer structure is an air outlet duct, the left end is closed, and the right end is connected to the air inlet duct; a ventilation hole connected to the air collecting hood is opened on the outside of the air outlet duct; one side of the air collecting hood is connected to the kiln head hood, and a gap is left between the other side and the air outlet duct, and an annular metal plate is fixedly connected to the outside of the air outlet duct, the annular metal plate is arranged in the air collecting hood and can contact the air collecting hood, and the annular metal plate forms a mechanical seal with the air collecting hood;

[0009] The kiln head cover is used to connect the rotary kiln with the cooler or subsequent equipment; the sealing structure is composed of a number of elastic plates, one end of the elastic plate is fixed to the kiln head cover by bolts, and the other end is pressed against the adjacent elastic plate, and the elastic plate arranged at the bottom is pressed against the connecting structure outside the cooling air duct;

[0010] The air collecting hood is provided with more than three pipe interfaces for connecting with the dust collector.

[0011] The dust removal fan is a centrifugal induced draft fan.

[0012] The inlet of the dust removal fan is provided with a manual butterfly valve, and the outlet of the combustion-supporting fan is provided with a manual butterfly valve.

[0013] The chimney is a steel chimney, and the bottom of the chimney is connected to the dust removal fan through a pipeline.

[0014] The combustion-supporting blower is a Roots blower.

[0015] The air inlet and the air outlet, and the air inlet and the kiln head cylinder are supported by rib plates.

[0016] The regulating valve is an electric regulating butterfly valve.

[0017] The dust collector is a bag dust collector.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] 1. The utility model can utilize dust collecting wind to realize cooling of kiln mouth and collection of spilled dust at the same time, and the equipment has high integration degree; it ensures the stable operation of the system under special circumstances such as rotary kiln system failure, kiln drying, low production, etc.

[0020] 2. Use dust collection wind to cool the metal structure of the kiln head. Use one dust removal fan, saving the use of kiln head cooling fans (usually two centrifugal fans) and corresponding pipelines, saving land, reducing the primary investment and maintenance cost of the equipment;

[0021] 3. The utility model can remove dust from the kiln head cooling and dust collecting hot air so that its dust concentration reaches the use standard of the combustion-supporting fan to supply the combustion-supporting fan, thereby realizing the utilization of the hot air after heat exchange in the cooling kiln head and improving the thermal efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a device used for cooling, dust removal and waste heat utilization of a rotary kiln head.

[0023] Figure 2 It is a schematic diagram of the kiln head cooling structure.

[0024] In the figure: 1-kiln head cooling structure 2-dust collector 3-dust removal fan 4-chimney 5-combustion-supporting fan 6-regulating valve;

[0025] 101 - cooling air duct 102 - ventilation hole 103 - kiln head cover 104 - sealing structure 105 - air collecting cover 106 - rib plate 107 - annular metal plate 108 - kiln head cylinder. DETAILED DESCRIPTION

[0026] The present invention is described in detail below in conjunction with the accompanying drawings of the specification, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0027] See Figure 1 , Figure 2 A device for cooling, dust removal and waste heat utilization of a rotary kiln head, comprising a kiln head cooling structure 1, a dust collector 2, a dust removal fan 3, a chimney 4, a combustion-supporting fan 5, and a regulating valve 6. The kiln head cooling structure 1, the dust collector 2, the dust removal fan 3, and the chimney 4 are connected in sequence through pipelines; the outlet of the combustion-supporting fan 5 is connected to the burner through a pipeline, the inlet of the combustion-supporting fan 5 is connected to a three-way pipe, one interface of the three-way pipe is connected to the regulating valve 6 and then connected to the atmosphere, and the other interface is connected to the outlet of the dust removal fan 3.

[0028] Among them, the dust removal fan 3 is a centrifugal induced draft fan with a fixed frequency motor, and a manual butterfly valve is set at the inlet of the centrifugal induced draft fan. The chimney 4 is a steel chimney, and the bottom of the chimney 4 is connected to the dust removal fan 3 through a pipeline. The combustion-supporting fan 5 is a Roots blower with a variable frequency motor, and the outlet of the combustion-supporting fan 5 is connected to a manual butterfly valve. The outlet of the combustion-supporting fan 5 is connected to the combustion-supporting air interface of the burner through a pipeline. The regulating valve 6 is an electric regulating butterfly valve. The dust collector 2 is a bag dust collector 2, and the inlet of the dust collector 2 is connected to the pipeline interface on the air collecting hood 105 through a pipeline, and the outlet is connected to the dust removal fan 3 through a pipeline.

[0029] See Figure 2 The kiln head cooling structure 1 includes a cooling air duct 101, an air collecting hood 105, a kiln head hood 103, and a sealing structure 104; the cooling air duct 101 is a two-layer structure, the first layer structure is close to the kiln head cylinder 108, the first layer structure is the air inlet duct, the left end is open, and the right end is connected to the rotary kiln; the second layer structure is the air outlet duct, the left end is closed, and the right end is connected to the air inlet duct. A ventilation hole 102 connected to the air collecting hood 105 is opened on the outside of the air outlet duct, and the hot air passing through the air outlet duct enters the air collecting hood 105 through the ventilation hole 102; fresh air enters from the left side of the air inlet duct, enters the air collecting hood 105 through the ventilation hole 102 through the air outlet duct, and then enters the dust collector 2 through the air collecting hood 105 through the pipeline.

[0030] One side of the gas collecting hood 105 is connected to the kiln head hood 103, and a gap is left between the other side and the air outlet duct. An annular metal plate 107 is fixedly connected to the outside of the air outlet duct. The annular metal plate 107 is arranged in the gas collecting hood 105 and can contact the gas collecting hood 105. The annular metal plate 107 and the gas collecting hood 105 form a mechanical seal a, which can block the external cold air from entering the gas collecting hood 105. The annular metal plate 107 rotates with the cooling air duct 101 and the kiln head cylinder 108, and does not affect the gas in the cooling air duct 101 from being extracted by the gas collecting hood 105.

[0031] The kiln head cover 103 is used to connect the rotary kiln with the cooler or subsequent equipment; the sealing structure 104 is composed of a plurality of elastic plates, one end of the elastic plate is fixed to the kiln head cover 103 by bolts, and the other end is pressed against the adjacent elastic plate. The elastic plates are arranged one on top of another, and the elastic plate arranged at the bottom is pressed against the connecting structure outside the cooling air duct 101.

[0032] The air collecting hood 105 is provided with more than three pipe interfaces, which are connected to the dust collector 2 through pipes to ensure that sufficient air volume passes through the air collecting hood 105. The air inlet and the air outlet, and the air inlet and the kiln head cylinder 108 are supported by rib plates 106.

[0033] See Figure 1 , Figure 2 , a method for cooling, dust removal and waste heat utilization of a rotary kiln head, comprising the following steps:

[0034] 1) The dust removal fan 3 provides a power source, passes through the pipeline, the bag dust collector 2, and the air collecting hood 105 in sequence, and generates negative pressure in the air collecting hood 105, so that fresh air enters the air collecting hood 105 through the kiln head cooling structure 1; the fresh air cools the kiln head metal structure in the process of passing through the kiln head cooling structure 1, and the air collecting hood 105 covers the sealed outer side of the kiln head hood 103. The air after heat exchange entering the air collecting hood 105 sends the overflowed dust into the dust removal pipeline;

[0035] 2) The air that has cooled the metal structure of the kiln head and carried dust is transported to the dust collector 2 through the dust removal pipeline. After dust removal, the dust in the gas is collected so that the dust concentration in the gas reaches the standard for discharge or use of the combustion-supporting fan 5;

[0036] 3) When the combustion-supporting fan 5 fails, in the early stage of kiln drying or the output of the rotary kiln is very low, the flow rate of the combustion-supporting fan 5 is low, the gas after dust removal does not enter the combustion-supporting fan 5 or enters the combustion-supporting fan 5 in small quantities, and the remaining part is discharged through the chimney 4;

[0037] During normal production, the dust-removed gas can be transported to the burner through the combustion-supporting fan 5 for use, thereby realizing waste heat recovery and utilization; when the temperature of the hot air after heat exchange and dust removal is too high, the regulating valve 6 at the front inlet of the combustion-supporting fan 5 is used to control the flow rate of cold air entering the combustion-supporting fan 5, thereby adjusting the temperature of the hot air entering the combustion-supporting fan 5.

[0038] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device for cooling, dust removal and waste heat utilization of a rotary kiln head, characterized in that: Including kiln head cooling structure, dust collector, dust removal fan, chimney, combustion-supporting fan, regulating valve; The kiln head cooling structure, dust collector, dust removal fan and chimney are connected in sequence through pipelines; the outlet of the combustion-supporting fan is connected to the burner through a pipeline, and the inlet of the combustion-supporting fan is connected to a three-way pipe. One interface of the three-way pipe is connected to the atmosphere after connecting to the regulating valve, and the other interface is connected to the outlet of the dust removal fan.

2. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 1, characterized in that: The kiln head cooling structure comprises a cooling air duct, an air collecting hood, a kiln head hood and a sealing structure; the cooling air duct is a two-layer structure, the first layer structure is close to the kiln head cylinder, the first layer structure is an air inlet duct, the left end is open, and the right end is connected to the rotary kiln; the second layer structure is an air outlet duct, the left end is closed, and the right end is connected to the air inlet duct; a ventilation hole connected to the air collecting hood is opened on the outside of the air outlet duct; one side of the air collecting hood is connected to the kiln head hood, and a gap is left between the other side and the air outlet duct, and an annular metal plate is fixedly connected to the outside of the air outlet duct, the annular metal plate is arranged in the air collecting hood and can contact the air collecting hood, and the annular metal plate forms a mechanical seal with the air collecting hood; The kiln head cover is used to connect the rotary kiln with the cooler or subsequent equipment; the sealing structure is composed of a number of elastic plates, one end of the elastic plate is fixed to the kiln head cover by bolts, and the other end is pressed against the adjacent elastic plate, and the elastic plate arranged at the bottom is pressed against the connecting structure outside the cooling air duct; The air collecting hood is provided with more than three pipe interfaces for connecting with the dust collector.

3. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 1, characterized in that: The dust removal fan is a centrifugal induced draft fan.

4. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 1, characterized in that: The inlet of the dust removal fan is provided with a manual butterfly valve, and the outlet of the combustion-supporting fan is provided with a manual butterfly valve.

5. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 1, characterized in that: The chimney is a steel chimney, and the bottom of the chimney is connected to the dust removal fan through a pipeline.

6. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 1, characterized in that: The combustion-supporting blower is a Roots blower.

7. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 2, characterized in that: The air inlet and the air outlet, and the air inlet and the kiln head cylinder are supported by rib plates.

8. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 1, characterized in that: The regulating valve is an electric regulating butterfly valve.

9. The device for cooling, dust removal and waste heat utilization of a rotary kiln head according to claim 1, characterized in that: The dust collector is a bag dust collector.

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