Rotary kiln cylinder waste heat recovery heat exchanger

Abstract

The utility model discloses a rotary kiln cylinder waste heat recovery heat exchanger which is composed of a heat exchanger body and comprises a heat reflecting plate, a radiation heat exchange mechanism and a heat preservation layer. The rotary kiln cylinder is wrapped with the heat reflecting plate. A first support, a second support and a third support are arranged on the heat reflecting plate; the radiation heat exchange mechanism is connected with the inner surface of the heat reflecting plate through a pipe clamp; the outer surface of the heat reflecting plate is connected with the heat preservation layer through reinforcing ribs arranged on the heat reflecting plate. By means of radiation heat exchange, convection heat exchange and conduction heat exchange, waste heat recycling of the rotary kiln cylinder is enhanced, and energy conservation and consumption reduction are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of waste heat utilization, and more specifically, to a waste heat recovery heat exchanger for heat dissipation of a rotary kiln. Background Art

[0002] The rotary kiln is a calcining equipment used in the industrial field, mainly used in cement rotary kiln, lime rotary kiln, alumina clinker calcining kiln, kaolin calcining kiln, carbon calcining kiln, ore roasting and other industrial fields. For the rotary kiln of cement plant with daily output of 5000t / d clinker, the outer diameter of the kiln cylinder is 4.2~5.0m, and the surface temperature of the kiln cylinder near the kiln head can reach 320~350℃; for the 200,000 tons / year kaolin calcining kiln, the diameter of the rotary kiln is 4.2m, and the surface temperature of the kiln cylinder can reach up to 280℃, with a large amount of waste heat. At present, the heat on the surface of the rotary kiln is mainly dissipated into the air, resulting in a large waste of energy.

[0003] At present, the concept of energy saving is deeply rooted in people's minds, and various industrial fields are studying relevant technologies and equipment for energy saving. Therefore, for the waste heat recovery of the rotary kiln cylinder, a heat exchanger with high recovery efficiency is needed. Utility Model Content

[0004] In view of the above situation, the utility model provides a rotary kiln shell waste heat recovery heat exchanger, which enhances the radiation heat exchange capacity and recovers waste heat to the maximum extent through many measures such as heat exchange tube bundle module selection, reasonable layout, and the use of heat reflector plates; the heat exchanger mainly absorbs radiation heat, while absorbing a small amount of convective heat transfer and heat preservation heat of the heat reflector plates.

[0005] Specifically, the utility model is implemented through the following technical solutions:

[0006] The present invention provides a rotary kiln cylinder waste heat recovery heat exchanger, which is composed of a heat exchanger body. The cylinder waste heat recovery heat exchanger includes a heat reflection plate, a radiation heat exchange mechanism and a heat preservation layer; the heat reflection plate is wrapped on the rotary kiln cylinder; the heat reflection plate is provided with a first support, a second support and a third support for support; the radiation heat exchange mechanism is connected to the inner surface of the heat reflection plate through a pipe clamp; the outer surface of the heat reflection plate is connected to the heat preservation layer through a reinforcing rib arranged thereon.

[0007] Furthermore, the heat reflection plate is connected to the rotary kiln cylinder at an angle; the heat reflection plate is a circular steel plate with an angle of 270° and a thickness of 6 to 10 mm.

[0008] Furthermore, a first heat absorption layer is provided inside the heat reflection plate.

[0009] Furthermore, the radiation heat exchange mechanism is composed of several groups of heat exchange tube bundle modules; each group of heat exchange tube bundle modules is provided with a water supply port and a water supply and sewage outlet at one end, and a water outlet and a water outlet and sewage outlet at the other end; each group of heat exchange tube bundle modules is also provided with an exhaust port.

[0010] Furthermore, the distance between the radiation heat exchange mechanism and the outer surface of the rotary kiln cylinder is set to 150-180 mm.

[0011] Furthermore, a second heat absorption layer is provided on the outer surface of the radiation heat exchange mechanism.

[0012] Furthermore, each group of the heat exchange tube bundle modules adopts serpentine tubes, the length direction of the serpentine tubes is arranged parallel to the center line of the rotary kiln cylinder, the serpentine tubes are Φ48×3, and the spacing is 80-120 mm.

[0013] Furthermore, the thermal insulation layer is composed of a thermal insulation layer and a protective layer. The thermal insulation layer is arranged between the outer surface of the heat reflector plate and the reinforcing ribs, and is laid along the outer surface of the heat reflector plate; the protective layer is arranged on the outer surface of the thermal insulation layer; the thermal insulation layer is composed of an insulating material with a thickness of 100 to 120 mm.

[0014] Beneficial Effects

[0015] 1. The utility model enhances the heat exchange effect of the rotary kiln cylinder waste heat by reasonably arranging several groups of heat exchanger tube bundle modules and setting heat reflection plates.

[0016] 2. The heat transfer method of the utility model covers three heat transfer methods, namely, the heat reflector plate, the radiation heat exchange mechanism and the heat preservation layer realize radiation heat exchange, convection heat exchange and heat preservation heat exchange for the waste heat of the rotary kiln cylinder, thereby enhancing the heat exchange effect.

[0017] 3. The utility model ensures the stability of the whole equipment and is beneficial to the heat exchange and insulation construction by reasonably arranging the heat reflection plate and the reinforcing ribs.

[0018] 4. The first heat absorption layer and the second heat absorption layer of the utility model are painted black to increase the radiation heat absorption capacity and enhance the heat exchange effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a cross-sectional layout diagram of the waste heat recovery heat exchanger of the utility model;

[0020] Figure 2 This is a schematic diagram of the heat exchange tube bundle module of the utility model;

[0021] Figure 3 This is a partial enlarged view of the waste heat recovery heat exchanger of the rotary kiln cylinder of the utility model.

[0022] Reference numerals:

[0023] 100, radiation heat exchange mechanism; 101, water supply port; 102, water supply and drainage port; 103, water outlet; 104, water outlet and drainage port; 105, heat exchange tube bundle module; 106, exhaust port; 107, pipe clamp; 108, second heat absorption layer; 201, first support; 202, second support; 203, third support; 204, heat reflection plate; 205, reinforcement rib; 206, first heat absorption layer; 300, heat preservation layer; 301, heat preservation layer; 302, protective layer; 400, rotary kiln shell DETAILED DESCRIPTION

[0024] The utility model patent is further described below in conjunction with the accompanying drawings.

[0025] like Figure 1 As shown, the utility model provides a rotary kiln cylinder waste heat recovery heat exchanger, the cylinder waste heat recovery heat exchanger includes a heat reflection plate 204, a radiation heat exchange mechanism 100 and a heat preservation layer 300; the heat reflection plate 204 is a 270° circular steel plate; the rotary kiln is wrapped by three groups of supports; the three groups of supports include: a first support 201, a second support 202 and a third support 203 are respectively welded and connected to the heat reflection plate to support the heat reflection plate, and then support the rotary kiln cylinder waste heat recovery heat exchanger. The first support 201, the second support 202 and the third support 203 need to be designed on the ground or on the rotary kiln operating platform according to the site conditions of the rotary kiln site, and the brackets are supported or fixed to the above three supports (201, 202, 203). The thickness is 6 to 10 mm, which plays a role in heat reflection and is also the skeleton of the whole equipment. The utility model takes into account that rotary kilns are generally equipped with temperature scanners to scan and monitor the surface temperature of the kiln cylinder 400. Therefore, it is necessary to reserve space in the area 150mm above and below the center line of the kiln, and no other obstructions can be set except for the support. The cylinder scanning space is reserved at the center line position on one side of the kiln. Therefore, the anti-heat plate 204 is arranged at an angle to the rotary kiln cylinder 400. The anti-heat plate 204 is connected to the separately arranged bracket through the first support 201, the second support 202 and the third support 203 respectively; the first support 201, the second support 202 and the third support 203 support the anti-heat plate 204, and the three groups of supports (201, 202, 203) all use double 12# channel steel. According to the stress characteristics of the anti-heat plate 204, the outer layer of the anti-heat plate 204 is provided with reinforcing ribs 205; the reinforcing ribs 205 are made of multiple groups of 10# channel steel welded into an arc frame as reinforcing ribs to reinforce the anti-heat plate 204. The inner layer of the heat reflection plate 204 is coated with a first heat absorption layer 206 .

[0026] The radiation heat exchange mechanism 100 is connected to the inner layer 204 of the heat reflector plate through the pipe clamp 107; in the radiation heat exchange mechanism of the utility model, each group of heat exchange tube bundle modules 205 maintains a certain distance from the outer surface of the rotary kiln cylinder 400. Due to the principle of temperature pressure and thermal expansion, the internal air flows from the surface of the rotary kiln cylinder to the heat exchange tube bundle module, bringing about convective heat exchange.

[0027] Wherein: the radiation heat exchange mechanism 100 is composed of several groups of heat exchange tube bundle modules 105; one end of each group of heat exchange tube bundle modules 105 is provided with a water supply port and a water supply and sewage outlet, and the other end is provided with a water outlet and a water outlet and sewage outlet; each group of heat exchange tube bundle modules 105 is connected to the heat reflector 204 through a pipe clamp 107; each group of heat exchange tube bundle modules 105 is also provided with an exhaust port 106. The heat exchange tube bundle modules 105 in the utility model are kept at a certain distance from the outer surface of the rotary kiln. If the distance is too small, the rotary kiln will expand, deform and occasionally jump during the operation of the rotary kiln, which will scrape against the heat exchange tube bundle modules; if the distance is too large, the heat absorption effect of the radiation heat exchanger will be reduced. The distance between each group of heat exchange tube bundle modules 105 and the outer surface of the rotary kiln cylinder 400 is set to 150-180 mm. A second heat absorption layer 108 is also coated on each group of heat exchange tube bundle modules 105. Each group of heat exchange tube bundle modules 105 of the utility model adopts a serpentine tube, and the length direction of the serpentine tube 105 is arranged parallel to the center line of the rotary kiln cylinder 400. The serpentine tube 205 uses a Φ48×3 seamless steel pipe with a spacing of 80 to 120 mm. The cold water in each group of heat exchange tube bundle modules 105 enters the heat exchanger from the water inlet, becomes hot water after heat exchange, and is supplied to subsequent heat users from the water outlet 103. The interface sizes of the water inlet 101 and the water outlet 103 are both DN40. An exhaust port 106 is provided at the top of each group of heat exchange tube bundle modules 105, and the interface size of the exhaust port 106 is DN25.

[0028] The thermal insulation layer 300 is composed of a thermal insulation layer 301 and a protective layer 302. The thermal insulation layer 301 is arranged on the outer surface of the heat reflector plate and between the reinforcing ribs, and is laid along the outer surface of the heat reflector plate 204; the protective layer 302 is arranged on the outer surface of the thermal insulation layer 301; the thermal insulation layer 301 is composed of an insulating material with a thickness of 100 to 120 mm. In the utility model, the thermal insulation layer 301 adopts a thermal insulation blanket, such as a composite silicate blanket; rock wool thermal insulation felt. In the utility model, the thermal insulation layer 301 is covered with a 100 to 120 mm thick thermal insulation blanket for insulation, and an outer protective layer 302 is arranged outside the thermal insulation layer, such as a galvanized iron sheet, to reinforce the thermal insulation blanket.

[0029] The utility model is used in the actual application process:

[0030] The utility model discloses a radiation heat exchange mechanism in a rotary kiln cylinder waste heat recovery heat exchanger, comprising a heat exchange tube bundle module 105, on which a water inlet 101 and a water outlet 103 are arranged, and the pipe diameters are all DN40. Cold water enters the heat exchanger tube bundle 105 from the water inlet 101 for heat exchange, and the flow rate of the water inlet 101 can be adjusted according to the water temperature of the water outlet 103. The heat exchange tube bundle module 105 adopts Φ48×3 seamless steel pipes with a spacing of 80 to 120 mm, and the working medium water flows slowly in the tube bundle. The heat exchange tube bundle module 105 is fixed to the heat reflector 204 with a pipe clamp. An exhaust port 106 is arranged at the top of the heat exchange tube bundle module 105, and the pipe diameter is DN25, which can discharge the stagnant gas in the tube bundle as needed. The water inlet 101 and the water outlet 103 are provided with sewage outlets (102, 104), and the sewage outlet pipe diameter is DN25, which can regularly discharge impurities in the water. The outer surface of the heat exchange tube bundle module 105 is provided with a heat absorption layer. In the utility model, the outer surface of the heat exchange tube bundle module 105 is painted black as a heat absorption layer to increase the heat absorption effect of radiant heat.

[0031] The rotary kiln shell waste heat recovery heat exchanger is also provided with a heat reflector 204 and a heat reflector reinforcing rib 205. In addition to serving as the equipment skeleton, the heat reflector 204 can also absorb radiant heat within a 270° angle range, and then transfer the absorbed heat to the heat exchange tube bundle module 105. The inner surface of the heat reflector 204 is painted black to increase the heat absorption capacity of radiant heat. The heat reflector is an 8mm thick steel plate. On the outside of the heat reflector 204, according to the stress condition of the heat reflector, 10# channel steel is used as a reinforcing rib 205 to reinforce the heat reflector.

[0032] The heat preservation layer 300 in a rotary kiln shell waste heat recovery heat exchanger includes a heat preservation blanket 301 and an outer protective layer 302. The heat preservation blanket 301 has a thickness of 100 to 120 mm, and is laid along the outer surface of the heat reflection plate using the reflector plate reinforcement rib 205 as a keel. Outside the heat preservation blanket, a galvanized iron sheet or a corrugated steel sheet is used as the outer protective layer 302 to reinforce the heat preservation blanket.

[0033] The above is only the preferred implementation of the utility model patent, but the utility model patent is not limited to the above specific implementation. For ordinary technicians in this field, several modifications and improvements can be made without departing from the creative concept, which all fall within the scope of protection of this patent.

Claims

1. A rotary kiln shell waste heat recovery heat exchanger, consisting of a heat exchanger body, characterized in that: The cylinder waste heat recovery heat exchanger includes a heat reflector plate, a radiation heat exchange mechanism and a heat preservation layer; the heat reflector plate is wrapped around the rotary kiln cylinder, and a first support, a second support and a third support are arranged on the heat reflector plate; the radiation heat exchange mechanism is connected to the inner surface of the heat reflector plate through a pipe clamp; the outer surface of the heat reflector plate is connected to the heat preservation layer through the reinforcing ribs arranged thereon.

2. A rotary kiln shell waste heat recovery heat exchanger according to claim 1, characterized in that: The heat reflection plate is connected to the rotary kiln cylinder at an angle; the heat reflection plate is a 270° circular steel plate with a thickness of 6 to 10 mm.

3. A rotary kiln shell waste heat recovery heat exchanger according to claim 1, characterized in that: The inner layer of the heat reflector plate is coated with a first heat absorbing layer.

4. A rotary kiln shell waste heat recovery heat exchanger according to claim 1, characterized in that: The radiation heat exchange mechanism is composed of several groups of heat exchange tube bundle modules; one end of each group of heat exchange tube bundle modules is provided with a water supply port and a water supply and sewage outlet, and the other end is provided with a water outlet and a water outlet and sewage outlet; each group of heat exchange tube bundle modules is also provided with an exhaust port.

5. The rotary kiln shell waste heat recovery heat exchanger according to claim 1, characterized in that: The distance between the radiation heat exchange mechanism and the outer surface of the rotary kiln cylinder is set to 150-180 mm.

6. The rotary kiln shell waste heat recovery heat exchanger according to claim 1, characterized in that: The outer layer of the radiation heat exchange mechanism is coated with a second heat absorbing layer.

7. A rotary kiln shell waste heat recovery heat exchanger according to claim 4, characterized in that: Each group of the heat exchange tube bundle modules adopts serpentine tubes, the length direction of the serpentine tubes is arranged parallel to the center line of the rotary kiln cylinder, the serpentine tubes are Φ48×3, and the spacing is 80mm-120mm.

8. The rotary kiln shell waste heat recovery heat exchanger according to claim 1, characterized in that: The heat preservation layer is composed of a heat preservation layer and a protective layer. The heat preservation layer is arranged between the outer surface of the heat reflection plate and the reinforcing ribs and is laid along the outer surface of the heat reflection plate; the protective layer is arranged on the outer surface of the heat preservation layer; the heat preservation layer is composed of an insulating material with a thickness of 100 to 120 mm.

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