CN-116592653-B - Waste heat recycling rotary kiln for red mud material thermal reaction

CN116592653BCN 116592653 BCN116592653 BCN 116592653BCN-116592653-B

Abstract

The invention discloses a waste heat recycling rotary kiln for thermal reaction of red mud materials, which is characterized by comprising an inner cylinder body with a feed inlet and a discharge outlet, an outer cylinder body, a combustion engine with a fire outlet, a power device, a lifting plate, a heat conducting pipe and a smoke outlet, wherein the lifting plate is connected to the inner wall of the inner cylinder body, the power device is connected with the inner cylinder body and can drive the inner cylinder body to rotate along the axis of the inner cylinder body, the inner cylinder body is positioned in the outer cylinder body, an annular cavity is arranged between the outer cylinder body and the inner cylinder body, the fire outlet of the combustion engine is connected with the outer cylinder body and extends into the annular cavity, two ends of the heat conducting pipe are connected with the inner wall of the inner cylinder body and extend into the annular cavity, and the smoke outlet is positioned on the wall surface of the outer cylinder body and is communicated with the annular cavity. Realizes the outer flame heating without pollution to reactants, and has high heat energy utilization rate.

Inventors

Lv Guiqiong
QIN JIN
ZHU ZHAOHONG
ZHOU JUN
LAO RONGSHU

Assignees

四川省川机工程技术有限公司

Dates

Publication Date: 20260508
Application Date: 20230516

Claims (9)

1. A waste heat recycling rotary kiln for red mud material thermal reaction, characterized by comprising: an inner cylinder body with a feed inlet and a discharge outlet; An outer cylinder; a burner having a firing end; A heat pipe with an air inlet end and an air outlet end; The outer cylinder body is provided with a smoke outlet and a power device; The inner wall of the inner cylinder body is provided with a lifting plate; The power device can drive the inner cylinder to rotate along the axis of the inner cylinder; the inner cylinder body is positioned in the outer cylinder body, and an annular cavity is formed between the outer cylinder body and the inner cylinder body; The fire outlet end is connected with the outer cylinder body and extends into the annular cavity; The heat conducting pipe is arranged in the inner cylinder body, and the air inlet end and the air outlet end penetrate through the inner wall of the inner cylinder body; the smoke outlet is positioned on the wall surface of the outer barrel body and communicated with the annular cavity; the heat conducting pipe is obliquely arranged in the inner cylinder body, and the air outlet end of the heat conducting pipe is obliquely oriented to one end of the smoke outlet.
2. The waste heat recycling rotary kiln for the thermal reaction of the red mud materials according to claim 1, wherein, The side wall of the inner cylinder body at the bottom is provided with a charge layer along the area between the direction perpendicular to the length direction of the inner cylinder body and n/3 of the diameter of the inner cylinder body, wherein n is more than or equal to 1 and less than or equal to 2; the two ends of the top of the charging layer, which are contacted with the inner cylinder body, are respectively a first end part and a second end part; The fire outlet end of the burner is arranged towards the first end or the second end of the charge layer; The inner cylinder body is provided with a first rotating direction, and when the inner cylinder body rotates in the first rotating direction, the first end part or the second end part, which faces the fire outlet end, is close to the bottom of the charging layer.
3. The waste heat recycling rotary kiln for the thermal reaction of the red mud materials according to claim 1, wherein, The inner cylinder body sequentially comprises a preheating section and a high-temperature section from one end of the inner cylinder body, where the feed inlet is located, to one end of the inner cylinder body, where the discharge outlet is located, and the length of the high-temperature section is greater than that of the preheating section; the preheating section and the high-temperature section are respectively provided with a heat conduction pipe.
4. The waste heat recycling rotary kiln for the thermal reaction of the red mud materials according to claim 1, wherein, The device also comprises a space occupying column; The space occupying column is arranged in the heat conducting pipe, and a cavity is formed between the outer surface of the space occupying column and the inner wall of the heat conducting pipe.
5. The waste heat recycling rotary kiln for the thermal reaction of the red mud materials according to claim 4, wherein, And an air collecting space is arranged between the air inlet end and the tail end of the occupying column close to one side of the air inlet end.
6. The waste heat recycling rotary kiln for the thermal reaction of the red mud materials according to claim 5, wherein, The length of the wind collecting space in the length direction of the occupying column is more than 10cm.
7. The waste heat recycling rotary kiln for the thermal reaction of the red mud materials according to claim 6, wherein, And a heat conductor is arranged between the heat conducting pipe and the space occupying column, one end of the heat conductor is connected with the heat conducting pipe, and the other end of the heat conductor is connected with the space occupying column.
8. The waste heat recycling rotary kiln for the thermal reaction of the red mud materials according to claim 1, wherein, The cross section of the outer wall of the heat conduction pipe is provided with a tip, and the distance between two side edges connected with the tip on the cross section is gradually increased along the direction away from the tip; the tip is towards one end where the feed inlet is located.
9. The rotary kiln for recycling waste heat for thermal reaction of red mud materials according to claim 1, further comprising: a wind-receiving plate with an inner concave wall surface; the air-pocket plate is connected with the air inlet end of the heat conduction pipe, and the direction of the inner concave wall surface is the same as the rotation direction of the inner cylinder body.

Description

Waste heat recycling rotary kiln for red mud material thermal reaction Technical Field The invention relates to the technical field of thermal reaction, in particular to a waste heat recycling rotary kiln for thermal reaction of red mud materials. Background The red mud is tailings produced in the aluminum industry production process, has a complex mineral composition, mainly contains minerals such as Al 2O3、Fe2O3、SiO2 and the like, and generally has stronger alkalinity and corrosiveness. Typically on average 1 ton of alumina is produced, with 1.0-2.0 tons of red mud being produced. The red mud is rich in iron, aluminum, calcium, silicon, titanium, sodium, nickel, manganese, chromium, vanadium and scandium, yttrium and lanthanide rare earth elements, and can change waste into valuable and become benefit through comprehensive development and utilization, and especially under the condition of increasingly lacking mineral resources, the recovery of valuable metals in the red mud is increasingly important. How to develop and utilize the red mud with a lot of alarming and falling asleep for years truly realizes the modern production without tail, waste and secondary pollution, achieves the comprehensive treatment of the mine environment, is an important subject of common concern in China and countries around the world, and has very important practical significance in developing and utilizing the red mud. In the prior art, ferric oxide in red mud is reduced into magnetic ferroferric oxide through a high-temperature reduction reaction, and then the ferroferric oxide is separated through a magnetic separator to obtain magnetic fine iron powder. However, in the existing treatment process, red mud and a reactant are placed in a rotary kiln, flame generated by a burner is used for internal heating, and although the heating mode has high heat energy utilization rate, the fuel of the existing burner is usually coal dust, the burner generates flame and generates flue gas containing sulfur dioxide and nitrogen dioxide, and after the flue gas contacts with mineral materials in the red mud, sulfur-containing and nitrogen-containing compounds are generated, so that the separation difficulty of various subsequent mineral materials is increased, and the recovery rate of metal mineral materials is reduced. Therefore, a thermal reaction device which can be used for the thermal reaction of red mud, avoids the pollution of flue gas to red mud mineral aggregate and has high heat energy utilization rate is needed. Disclosure of Invention In order to solve the problems in the prior art, the invention provides a waste heat recycling rotary kiln for the thermal reaction of red mud materials. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a waste heat recycling rotary kiln for red mud material thermal reaction, characterized by comprising: an inner cylinder body with a feed inlet and a discharge outlet; An outer cylinder; a burner having a firing end; A heat pipe with an air inlet end and an air outlet end; The outer cylinder body is provided with a smoke outlet and a power device The inner wall of the inner cylinder body is provided with a lifting plate; The power device can drive the inner cylinder to rotate along the axis of the inner cylinder; the inner cylinder body is positioned in the outer cylinder body, and an annular cavity is formed between the outer cylinder body and the inner cylinder body; the fire outlet end of the burner is connected with the outer cylinder body and extends into the annular cavity; The heat conducting pipe is arranged in the inner cylinder body, and the air inlet end and the air outlet end penetrate through the inner wall of the inner cylinder body; the smoke outlet is positioned on the wall surface of the outer cylinder body and communicated with the annular cavity. Preferably, the smoke outlet is arranged at one end of the outer cylinder body close to the feeding hole; the heat conduction pipe is obliquely arranged in the inner cylinder body, and the air outlet end of the heat conduction pipe is obliquely oriented to one end of the smoke outlet. Preferably, the side wall of the inner cylinder body at the bottom is provided with a charge layer along the area between the direction perpendicular to the length direction of the inner cylinder body and n/3 of the diameter of the inner cylinder body, wherein n is more than or equal to 1 and less than or equal to 2; the two ends of the top of the charging layer, which are contacted with the inner cylinder body, are respectively a first end part and a second end part; The fire outlet end of the burner is arranged towards the first end or the second end of the charge layer; The inner cylinder body is provided with a first rotating direction, and when the inner cylinder body rotates in the first rotating direction, the first end part or the second end part, which faces the fire outlet end, is close to the botto