Energy-saving and environment-friendly external heating type rotary kiln

Abstract

The utility model discloses an energy-saving environment-friendly external heating type rotary kiln which comprises a first heat exchanger, one side of the first heat exchanger is communicated with a bag-type dust collector, the bag-type dust collector is communicated with a second heat exchanger through a pipeline, and a second hot air outlet is formed in the end, away from the bag-type dust collector, of the second heat exchanger. A condensate water collecting opening is formed in the bottom end of the second heat exchanger, a tail gas outlet is formed in the upper portion of the second heat exchanger, and a cofferdam is arranged below the second heat exchanger. The moisture in the tail gas is condensed through the condensation type heat exchanger, the total amount of the tail gas is reduced, the moisture in the tail gas is reduced, the service life of the activated carbon is prolonged, and dioxin treatment is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of rotary kilns, in particular to an energy-saving and environment-friendly externally heated rotary kiln. Background Art

[0002] The prior art discloses an externally heated thermal decomposition rotary kiln with application number CN201920372437.6, which enters the furnace tube through a closed feeding device for pyrolysis. The flue gas generated by furnace heating passes through a flue gas purification device and a heat exchange device, and then enters the combustion-supporting pipe of the burner under the action of a combustion-supporting fan, thereby realizing the recovery and utilization of flue gas heat. There is a nitrogen filling port at the feeding end of the furnace tube to ensure positive pressure and inert gas in the furnace to prevent explosion. The exhaust port is provided in the furnace to adjust the air pressure and temperature in the furnace.

[0003] However, the existing technology still has certain defects. For example, during the use of the technical solution of application number CN201920372437.6, chromium-containing sludge (leather making, electroplating, vanadium-containing, etc.) is classified as hazardous waste.

[0004] However, the existing technology still has certain defects. For example, the technical solution of application number CN202021480136.4 uses activated carbon to treat by-product chromium-containing sludge (leather making, electroplating, vanadium-containing, etc.), which is a hazardous waste. In addition, the traditional kiln is an internal heating type. When treating the chromium-containing sludge with a high water content, a large amount of water generated by the material evaporates into the exhaust gas, which is not conducive to the treatment of dioxins. Utility Model Content

[0005] In order to solve the deficiencies mentioned in the above background technology, the purpose of the present invention is to provide an energy-saving and environment-friendly externally heated rotary kiln.

[0006] The purpose of the utility model can be achieved through the following technical solutions:

[0007] An energy-saving and environmentally friendly externally heated rotary kiln includes a first heat exchanger, one side of the first heat exchanger is connected to a bag dust collector, the bag dust collector is connected to a second heat exchanger through a pipeline, a second hot air outlet is provided at one end of the second heat exchanger away from the bag dust collector, a condensate collection port is provided at the bottom end of the second heat exchanger, an exhaust gas outlet is provided above the second heat exchanger, and a cofferdam is provided below the second heat exchanger.

[0008] Furthermore, a combustion-supporting fan is fixedly provided on one side of the second heat exchanger.

[0009] Furthermore, a first hot air outlet is fixedly provided on one side of the first heat exchanger, and the first hot air outlet is connected to a hot air main pipe.

[0010] Furthermore, the externally heated rotary kiln further comprises a roasting furnace, which is provided with a natural gas fume recovery interface;

[0011] One end of the hot air main pipe is connected to the first hot air exhaust outlet, and the other end is connected to the natural gas fume recovery interface.

[0012] Furthermore, an array of natural gas burners is provided below the roasting furnace, and a natural gas combustion-supporting air duct and a natural gas main are provided on one side of the natural gas burner;

[0013] One end of the natural gas combustion-supporting air pipe is connected to the natural gas burner, and the other end is connected to the second heat exchanger;

[0014] A furnace barrel is provided through the roasting furnace, and the furnace barrel is rotatably connected to the roasting furnace.

[0015] Furthermore, the furnace drum is provided with an oxygen interface, a discharge port is provided at one end of the furnace drum, a feed pipe is provided at the other end, a feed screw conveyor is provided at one end of the feed pipe, a feed port is provided on the feed pipe, and an automatic gravity discharge valve is fixedly provided on the discharge port;

[0016] A connecting piece is provided between the feed pipe and the furnace drum, the connecting piece is fixedly connected to the feed pipe, and the connecting piece is rotatably connected to the furnace drum.

[0017] Furthermore, furnace drum supporting wheels are provided on both sides of the roasting furnace, and the furnace drum supporting wheels are located below the furnace drum and are used to support the furnace drum;

[0018] A driving member is provided below the furnace drum, and the driving member is used to drive the furnace drum to rotate on the furnace drum supporting wheel.

[0019] Furthermore, an exhaust manifold is provided between the connecting piece and the first heat exchanger, and an electric regulating valve and an oxygen sensor are provided on the exhaust manifold.

[0020] Furthermore, two electric regulating valves are provided on the hot air main pipe, and a centrifugal fan is provided on the hot air main pipe, and the air inlet of the centrifugal fan is located between the two electric regulating valves.

[0021] Beneficial effects of the utility model:

[0022] The exhaust gas passes through a condensing heat exchanger to condense the moisture in the exhaust gas, thereby reducing the total amount of the exhaust gas and the moisture in the exhaust gas, which is beneficial to increasing the service life of the activated carbon and facilitating dioxin treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings.

[0024] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0025] Figure 2 This is a structural diagram of the utility model from perspective 1;

[0026] Figure 3 This is a top view of the energy-saving and environmentally friendly rotary kiln of the utility model;

[0027] Figure 4 It is a partial structural diagram of the externally heated rotary kiln of the utility model. DETAILED DESCRIPTION

[0028] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0029] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inside", "around" and the like indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0030] An energy-saving and environmentally friendly external heating rotary kiln, such as Figure 1-Figure 3 As shown, it includes a first heat exchanger 3, a first hot air exhaust port 2 is fixedly provided on one side of the first heat exchanger 3, the first hot air exhaust port 2 is connected to the front end of the first heat exchanger 3, and a bag dust collector 4 is connected to the bag dust collector 4 through a pipeline. A second heat exchanger 17 is provided at one end of the second heat exchanger 17 away from the bag dust collector 4, a condensate collection port 6 is provided at the bottom end of the second heat exchanger 17 for collecting and recovering condensate, an exhaust gas outlet is provided above the second heat exchanger 17 for discharging exhaust gas in the furnace, and a cofferdam 7 is provided below the second heat exchanger 17.

[0031] In this embodiment, a combustion-supporting fan is fixedly provided on one side of the second heat exchanger 17 .

[0032] The first hot air outlet 2 is connected to a hot air main pipe 8;

[0033] The externally heated rotary kiln further includes a roasting furnace 13, on which a natural gas fume recovery interface 14 is provided;

[0034] One end of the hot air main pipe 8 is connected to the first hot air outlet 2 , and the other end is connected to the natural gas fume recovery interface 14 .

[0035] An array of natural gas burners 22 is provided below the roasting furnace 13, and a natural gas combustion air duct 18 and a natural gas main pipe 19 are provided on one side of the natural gas burner 22;

[0036] One end of the natural gas combustion-supporting air duct 18 is connected to the natural gas burner 22 , and the other end is connected to the second heat exchanger 17 ; the natural gas main pipe 19 provides natural gas to the natural gas burner 22 .

[0037] A furnace barrel 23 is provided through the roasting furnace 13, and the furnace barrel 23 is rotatably connected to the roasting furnace 13.

[0038] An oxygen interface is provided on the furnace drum 23 for supplying oxygen-enriched air or pure oxygen; a discharge port 20 is provided at one end of the furnace drum 23, and a feed pipe is provided at the other end. A feed screw conveyor 12 is provided at one end of the feed pipe, a feed port 9 is provided on the feed pipe, and an automatic gravity discharge valve 21 is fixedly provided on the discharge port 20.

[0039] A connecting piece is provided between the feed pipe and the furnace drum 23 , wherein the connecting piece is fixedly connected to the feed pipe and rotatably connected to the furnace drum 23 .

[0040] The outer wall of the furnace barrel 23 is heated by the natural gas burner 22, and the natural gas flue gas does not directly contact the material. The oxidizing atmosphere in the furnace can be adjusted separately. Negative pressure operation is adopted in the furnace barrel 23 to avoid dust leakage. Multiple natural gas burners 22 are used for heating, and each burner has independent temperature display and temperature control, which can adjust the roasting curve. Oxygen-enriched air or pure oxygen is used in the furnace barrel 23, and the oxygen intake is adjusted by detecting the oxygen content of the exhaust gas.

[0041] Furnace drum supporting wheels 16 are provided on both sides of the roasting furnace 13 . The furnace drum supporting wheels 16 are located below the furnace drum 23 and are used to support the furnace drum 23 .

[0042] A driving member 15 is provided below the furnace drum 23 , and the driving member 15 is used to drive the furnace drum 23 to rotate on the furnace drum supporting wheel 16 . The driving member 15 can be driven by a belt or a gear.

[0043] An exhaust manifold is provided between the connector and the first heat exchanger 3, and an electric regulating valve 10 and an oxygen sensor 11 are provided on the exhaust manifold.

[0044] Two electric regulating valves 10 are provided on the hot air main pipe 8 for controlling the air volume regulation of the hot air main pipe 8 . A centrifugal fan 1 is provided on the hot air main pipe 8 , and the air inlet of the centrifugal fan 1 is located between the two electric regulating valves 10 .

[0045] The main advantages of this embodiment are: natural gas flue gas is recovered, the flue gas is separated from the exhaust gas, and the flue gas can be used for air supply to the dryer; oxygen-enriched air or pure oxygen is used in the kiln to reduce the content of the exhaust gas; the heat of the exhaust gas is exchanged with a heat exchanger, and after the exhaust gas is cooled, it protects the bag dust collector; the exhaust gas passes through the condensing heat exchanger again to condense the moisture in the exhaust gas, reducing the total amount of exhaust gas. Reducing the moisture in the exhaust gas is beneficial to the long-term and reliable operation of the activated carbon (obtaining a low-temperature and low-moisture exhaust gas); the heat (hot air) recovered by the heat exchanger is combined with the natural gas flue gas and used for drying the chrome mud at the front end; the hot air exchanged by the condensing heat exchanger is used as the natural gas combustion air for the externally heated rotary kiln body; the gas heat is recovered to reduce carbon emissions; the total amount of exhaust gas and the moisture of the gas are reduced, which is beneficial to dioxin treatment.

[0046] Specifically, the external heating kiln can recover heat, and after the heat is recovered from the exhaust gas, the volume of the exhaust gas is also reduced, which can facilitate the treatment of dioxins.

[0047] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0048] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and improvements fall within the scope of the present invention as claimed.

Claims

1. An energy-saving and environmentally friendly externally heated rotary kiln, comprising a first heat exchanger (3), characterized in that: One side of the first heat exchanger (3) is connected to a bag dust collector (4), and the bag dust collector (4) is connected to a second heat exchanger (17) through a pipeline. A second hot air outlet (5) is provided at one end of the second heat exchanger (17) away from the bag dust collector (4), a condensate collection port (6) is provided at the bottom end of the second heat exchanger (17), an exhaust gas outlet is provided above the second heat exchanger (17), and a cofferdam (7) is provided below the second heat exchanger (17).

2. The energy-saving and environment-friendly externally heated rotary kiln according to claim 1, characterized in that: A combustion-supporting fan is fixedly provided on one side of the second heat exchanger (17).

3. An energy-saving and environment-friendly externally heated rotary kiln according to claim 1 or 2, characterized in that: A first hot air outlet (2) is fixedly provided on one side of the first heat exchanger (3), and the first hot air outlet (2) is connected to a hot air main pipe (8).

4. The energy-saving and environment-friendly externally heated rotary kiln according to claim 3, characterized in that: The externally heated rotary kiln further comprises a roasting furnace (13), and a natural gas fume recovery interface (14) is provided on the roasting furnace (13); One end of the hot air main pipe (8) is connected to the first hot air outlet (2), and the other end is connected to the natural gas fume recovery interface (14).

5. The energy-saving and environment-friendly externally heated rotary kiln according to claim 4, characterized in that: An array of natural gas burners (22) is provided below the roasting furnace (13), and a natural gas combustion-supporting air duct (18) and a natural gas main pipe (19) are provided on one side of the natural gas burner (22); One end of the natural gas combustion-supporting air pipe (18) is in communication with the natural gas burner (22), and the other end is in communication with the second heat exchanger (17); A furnace barrel (23) is provided through the roasting furnace (13), and the furnace barrel (23) is rotatably connected to the roasting furnace (13).

6. The energy-saving and environment-friendly externally heated rotary kiln according to claim 5, characterized in that: The furnace drum (23) is provided with an oxygen interface, a discharge port (20) is provided at one end of the furnace drum (23), a feed pipe is provided at the other end, a feed screw conveyor (12) is provided at one end of the feed pipe, a feed port (9) is provided on the feed pipe, and an automatic gravity discharge valve (21) is fixedly provided on the discharge port (20); A connecting piece is provided between the feed pipe and the furnace drum (23), the connecting piece is fixedly connected to the feed pipe, and the connecting piece is rotatably connected to the furnace drum (23).

7. The energy-saving and environment-friendly externally heated rotary kiln according to claim 6, characterized in that: Both sides of the roasting furnace (13) are provided with furnace drum supporting wheels (16), and the furnace drum supporting wheels (16) are located below the furnace drum (23) and are used to support the furnace drum (23); A driving member (15) is provided below the furnace drum (23), and the driving member (15) is used to drive the furnace drum (23) to rotate on the furnace drum supporting wheel (16).

8. The energy-saving and environment-friendly externally heated rotary kiln according to claim 6, characterized in that: An exhaust manifold is provided between the connecting piece and the first heat exchanger (3), and an electric regulating valve (10) and an oxygen sensor (11) are provided on the exhaust manifold.

9. The energy-saving and environment-friendly externally heated rotary kiln according to claim 3, characterized in that: The hot air main pipe (8) is provided with two electric regulating valves (10) for controlling the air volume of the hot air main pipe (8). The hot air main pipe (8) is provided with a centrifugal fan (1), and the air inlet of the centrifugal fan (1) is located between the two electric regulating valves (10).

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