Bottom air inducing mechanism for vertical kiln

Abstract

The bottom air inducing mechanism comprises a kiln body and a hot air pipe communicated with an inner cavity of the kiln body, the air inducing mechanism is arranged at the bottom of the kiln body and comprises a combustion-supporting air pipe, a heat exchange pipe, a mixing pipe and a gas pipe, and a hot air cavity of the heat exchange pipe is communicated with the hot air pipe. The combustion-supporting gas pipe is communicated with a heat exchange cavity of the heat exchange pipe, the gas inlet end of the mixing pipe is communicated with the combustion-supporting gas pipe and the gas outlet end of the gas pipe, and the gas outlet end of the mixing pipe is communicated with the bottom of the kiln body. The bottom air inducing mechanism can comprehensively utilize a part of heat or flue gas in the kiln and heat external combustion-supporting gas and fuel gas, so that the temperature required to be absorbed during combustion is reduced, the combustion effect in the kiln is ensured, the temperature is stable, and the product firing quality is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of vertical kilns, in particular to a bottom air induction mechanism for a vertical kiln. Background Art

[0002] Vertical kilns (hereinafter referred to as vertical kilns) are commonly found in lime kilns. Vertical kilns are divided into preheating section (heating section), high temperature section (firing section) and cooling section (low temperature section) from top to bottom. Raw materials (stones) are put into the vertical kiln from the top for combustion. During combustion, the bottom (cooling section) generally draws air and transports combustibles (commonly gas) at the same time. In colder environments or seasons, direct air or gas supply is difficult to control the combustion temperature in the kiln due to the low temperature. At the same time, it is also necessary to absorb the temperature in the kiln to heat up, which greatly affects the use of the kiln and the quality of the fired products. Utility Model Content

[0003] The utility model aims to provide a bottom air induction mechanism for a vertical kiln to solve the problem.

[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0005] A bottom draft mechanism for a vertical kiln comprises a kiln body and a hot air pipe connected to the inner cavity of the kiln body, the bottom of the kiln body is provided with the draft mechanism, the draft mechanism comprises a combustion-supporting pipe, a heat exchange pipe, a mixing pipe and a gas pipe, the hot air cavity of the heat exchange pipe is connected to the hot air pipe, the combustion-supporting pipe is connected to the heat exchange cavity of the heat exchange pipe, the air inlet end of the mixing pipe is connected to the combustion-supporting pipe and the air outlet end of the gas pipe respectively, and the air outlet end of the mixing pipe is connected to the bottom of the kiln body.

[0006] A further technical solution is: the heat exchange tube includes an inner tube, an outer tube, a spiral plate and a sealing ring, the inner tube is installed on the hot air tube, the outer tube is sleeved on the inner tube, the spiral plate is located between the inner tube and the outer tube and forms a spiral heat exchange cavity, and the sealing ring seals both ends of the heat exchange cavity.

[0007] A further technical solution is that the gas flow direction in the heat exchange cavity is opposite to the gas flow direction in the inner tube.

[0008] A further technical solution is: a one-way valve is arranged on the mixing tube.

[0009] A further technical solution is that the diameter of the mixing tube is larger than the diameters of the combustion-supporting gas tube and the gas tube.

[0010] A further technical solution is that the air inlet end of the hot air pipe is connected to the high temperature section or preheating section of the kiln body.

[0011] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0012] The utility model provides a bottom draft mechanism for a vertical kiln, which can comprehensively utilize a part of the heat or smoke in the kiln to heat external combustion-supporting gas and fuel gas, reduce the temperature required to be absorbed during combustion, ensure the combustion effect in the kiln and the temperature is stable, and improve the firing quality of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The utility model is a structural schematic diagram of a bottom draft mechanism for a vertical kiln.

[0014] Figure 2 For this utility model Figure 1 Schematic diagram of the structure of the heat exchange tube.

[0015] Figure numerals: 1. kiln body; 2. hot air pipe; 3. induced draft mechanism; 4. combustion-supporting gas pipe; 5. heat exchange pipe; 51. inner pipe; 52. outer pipe; 53. spiral plate; 54. sealing ring; 6. mixing pipe; 7. gas pipe. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0017] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0018] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0019] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0020] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, or the positions or positional relationships commonly understood by those skilled in the art, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Embodiment 1:

[0022] In this embodiment, Figure 1 and Figure 2 As shown, a bottom draft mechanism for a vertical kiln comprises a kiln body 1 and a hot air pipe 2 connected to the inner cavity of the kiln body 1, an draft mechanism 3 is arranged at the bottom of the kiln body 1, the draft mechanism 3 comprises a combustion-supporting pipe 4, a heat exchange pipe 5, a mixing pipe 6 and a gas pipe 7, the hot air cavity of the heat exchange pipe 5 is connected to the hot air pipe 2, the combustion-supporting pipe 4 is connected to the heat exchange cavity of the heat exchange pipe 5, the air inlet end of the mixing pipe 6 is connected to the air outlet ends of the combustion-supporting pipe 4 and the gas pipe 7 respectively, and the air outlet end of the mixing pipe 6 is connected to the bottom of the kiln body 1.

[0023] The induced draft mechanism can utilize the smoke temperature in the hot air pipe 2 (i.e., generally the excess heat in the kiln) to heat the combustion-supporting gas in the combustion-supporting gas pipe 4. The combustion-supporting gas pipe 4 is selected because, firstly, the combustion-supporting gas is generally oxygen or air, which is safer and will not cause too much danger even if a gas leak occurs and an open flame is encountered. Secondly, the combustion-supporting gas is generally in large demand and is constantly flowing into the kiln, carrying more heat. After the gas in the combustion-supporting gas pipe 4 is heated, it enters the mixing pipe 6, is mixed with the gas in the gas pipe 7 and the gas temperature is increased, and finally is sent into the kiln for use.

[0024] Preferably, the heat exchange tube 5 includes an inner tube 51, an outer tube 52, a spiral plate 53 and a sealing ring 54. The inner tube 51 is installed on the hot air tube 2, and the outer tube 52 is sleeved on the inner tube 51. The spiral plate 53 is located between the inner tube 51 and the outer tube 52 to form a spiral heat exchange cavity. The sealing ring 54 seals both ends of the heat exchange cavity.

[0025] The inner tube 51 passes the high-temperature flue gas in the kiln, and the gas in the combustion-supporting gas pipe 4 passes through the heat exchange cavity and exchanges heat with the high-temperature flue gas to achieve the effect of heating the combustion-supporting gas. The length of the heat exchange tube 5 affects the heating effect within a certain range.

[0026] Preferably, the gas flow direction in the heat exchange chamber is opposite to the gas flow direction in the inner tube 51 .

[0027] Generally speaking, the temperature of the flue gas in the inner tube 51 will gradually decrease along with the direction of its flow path, so setting the gas flow direction in the heat exchange cavity opposite to the direction of the flue gas flow path can improve the heat exchange effect to a certain extent.

[0028] Preferably, a one-way valve is provided on the mixing tube 6 .

[0029] Prevent flames from flowing back into the kiln and affecting safety.

[0030] Preferably, the diameter of the mixing tube 6 is larger than the diameters of the combustion-supporting tube 4 and the gas tube 7 .

[0031] After the combustible gas and the combustion-supporting gas are mixed, their volumes increase, so the mixing tube 6 needs to be enlarged to prevent other compressions. Compressed gas has certain dangers.

[0032] Preferably, the air inlet end of the hot air pipe 2 is connected to the high temperature section or the preheating section of the kiln body 1 .

[0033] Generally, the air inlet end of the hot air pipe 2 is connected to either the high temperature section or the preheating section, but both of them can also be connected. When the flue gas temperature is not high enough, the excess heat in the high temperature section can be used to ensure that the temperature of the low temperature section is not affected when the gas passes through the low temperature section.

[0034] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A bottom draft mechanism for a vertical kiln, characterized in that: The invention comprises a kiln body (1) and a hot air pipe (2) connected to the inner cavity of the kiln body (1); an air induction mechanism (3) is arranged at the bottom of the kiln body (1); the air induction mechanism (3) comprises a combustion-supporting pipe (4), a heat exchange pipe (5), a mixing pipe (6) and a gas pipe (7); the hot air cavity of the heat exchange pipe (5) is connected to the hot air pipe (2); the combustion-supporting pipe (4) is connected to the heat exchange cavity of the heat exchange pipe (5); the air inlet end of the mixing pipe (6) is connected to the air outlet ends of the combustion-supporting pipe (4) and the gas pipe (7) respectively; and the air outlet end of the mixing pipe (6) is connected to the bottom of the kiln body (1).

2. The bottom draft mechanism for a vertical kiln according to claim 1, characterized in that: The heat exchange tube (5) comprises an inner tube (51), an outer tube (52), a spiral plate (53) and a sealing ring (54); the inner tube (51) is mounted on the hot air tube (2); the outer tube (52) is sleeved on the inner tube (51); the spiral plate (53) is located between the inner tube (51) and the outer tube (52) to form a spiral heat exchange cavity; and the sealing ring (54) seals both ends of the heat exchange cavity.

3. The bottom draft mechanism for a vertical kiln according to claim 2, characterized in that: The gas flow direction in the heat exchange chamber is opposite to the gas flow direction in the inner tube (51).

4. The bottom draft mechanism for a vertical kiln according to claim 1, characterized in that: The mixing tube (6) is provided with a one-way valve.

5. The bottom draft mechanism for a vertical kiln according to claim 1, characterized in that: The diameter of the mixing tube (6) is greater than the diameters of the combustion-supporting gas tube (4) and the gas tube (7).

6. The bottom draft mechanism for a vertical kiln according to claim 1, characterized in that: The air inlet end of the hot air pipe (2) is in communication with the high temperature section or the preheating section of the kiln body (1).

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