A variable diameter hollow flue capable of removing ash accumulation and recycling flue gas heat

Abstract

The present invention discloses a variable diameter hollow flue which can remove dust accumulation and recycle the heat of flue gas. The variable diameter hollow flue is composed of a plurality of flue pipes with different pipe diameters, and two adjacent flue pipes are connected in a fixed connection manner. A pulse pipe is welded at an interval of 2-4 meters in the bottom area of ​​the variable diameter hollow flue, and the outer shell of the pulse pipe is welded to the outer wall of the variable diameter hollow flue to form a whole. The present invention aims to solve the technical problems of ensuring that the flue can withstand the emission of high-concentration SO2 flue gas for a long time, ensuring that the flue does not leak flue gas, automatically cleaning the dust accumulation, and recycle the heat at the same time.

Description

Technical Field

[0001] The invention relates to a variable diameter hollow flue which can remove dust accumulation and recycle the heat of flue gas. Background Art

[0002] At present, the flue gas discharge flue is made of solid flue built with large diameter refractory bricks. In the process of use, in addition to frequent flue gas leakage and a large amount of ash accumulation in the flue, most of the heat of the flue gas is wasted. The ash accumulation in the flue needs to be cleaned manually when the furnace is shut down or repaired. The cleaning time is long and the labor intensity is high. The heat of the flue gas is lost with the discharge. These traditional flues cause many inconveniences and energy losses to production. Summary of the invention

[0003] The technical problem to be solved by the present invention is to ensure that the flue can withstand the emission of high-concentration SO2 flue gas for a long time, to ensure that there is no flue gas leakage in the flue, and to automatically clean the accumulated ash, while also being able to recycle the heat. A variable-diameter hollow flue is provided that can remove accumulated ash and recycle the heat of the flue gas.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] A variable diameter hollow flue capable of removing dust accumulation and recycling heat from flue gas, the variable diameter hollow flue consisting of a plurality of flue pipes with different diameters, and two adjacent flue pipes being connected in a fixed manner; a pulse pipe fitting is welded at intervals of 2-4 meters in the bottom area of ​​the variable diameter hollow flue, and the outer shell of the pulse pipe fitting is welded to the outer wall of the variable diameter hollow flue to form a whole.

[0006] Preferably, the smoke pipe includes a first outer circular tube and a first inner circular tube, wherein the inner circular tube is arranged in the inner cavity of the first outer circular tube, and the height of the first inner circular tube is the same as the height of the first outer circular tube, and a plurality of recovery pipes arranged in a circular array are arranged between the outer wall of the first inner circular tube and the inner wall of the first outer circular tube, and each of the recovery pipes is connected to the connecting pipe by seamless welding or threaded connection; a socket-type connecting pipe is fixedly installed on one end of the first inner circular tube.

[0007] Preferably, the first outer circular tube is composed of an iron layer or an aluminum layer and an aluminum silicate wool layer.

[0008] Preferably, the first inner circular tube is cast from acid-resistant, alkali-resistant, and refractory materials, and the wall thickness thereof is in the range of 25-100 mm. The acid-resistant, alkali-resistant, and refractory materials are semi-mullite, aluminum silicate, or high-alumina refractory materials.

[0009] Preferably, the recovery pipe is a heat-resistant cast iron pipe or a stainless steel pipe, and the inner cavity of the recovery pipe is filled with liquid for taking away the heat inside the variable-diameter hollow flue, and the liquid is water or oil.

[0010] Preferably, a channel for compressed air to clean dust is provided in the middle of the pulse pipe fitting, the diameter of the channel ranges from 20-50mm, and the shape of the channel is round or square. A nozzle is provided at one end of the pulse pipe fitting, and the nozzle is located in the inner cavity of the variable diameter hollow flue. A pulse valve interface is provided at the other end of the pulse pipe fitting, and the pulse pipe fitting is wrapped with a shell made of heat-resistant stainless steel; the pulse pipe fitting is cast by acid-resistant, alkali-resistant and refractory materials, and its wall thickness ranges from 25-80mm.

[0011] Preferably, the diameter of the smoke pipe ranges from 350-600 mm to 1200-1600 mm.

[0012] Preferably, the fixed connection method includes a socket-and-spigot type plus a pipe seamless welding type or a threaded connection type.

[0013] Preferably, the variable diameter hollow flue is connected to the flue gas discharge port of the graphitization furnace.

[0014] Working principle of the present invention:

[0015] The variable diameter hollow flue is connected to the flue gas discharge port of the graphitization furnace. The SO2 flue gas of the graphitization high temperature furnace enters the flue through the discharge port. The flue diameter of the first graphitization furnace is 350-600mm, the flue diameter of the tenth graphitization furnace is 850-1100mm, and the diameter of the main flue is 1100-1600mm. The first inner round tube of all flues is connected by a socket-type method, and the middle recovery pipe is connected by a seamless welding process or a screw connection method. Water or oil can be passed through the recovery pipe, and the heat inside the flue is taken away by the circulation of water / oil, and finally collected to the thermal generator or directly into the centralized heating area for circulation. Compressed air enters the bottom of the pipe through the pulse pipes installed every 2-4 meters, blowing the accumulated dust in the direction of the movement of the flue gas. When the dust reaches the last flue pipe, it can be cleaned mechanically or manually by a dust removal device.

[0016] The beneficial effects achieved by the present invention are:

[0017] The present invention abandons the traditional masonry method of flue and creates a hollow flue that can recycle the heat energy of flue gas: each section of the flue pipe is connected by a socket-and-spigot + seamless welding process or a screw connection method. The minimum diameter of the first flue is 350-600mm, and then gradually changes to the last flue. When it reaches the final total (main) flue, its diameter is still only about 1200-1500mm.

[0018] The variable diameter design of the flue of the present invention can minimize the possibility of smoke leakage in the smoke pipe and reduce manufacturing costs. On the other hand, the heat of the flue gas can be recovered for power generation or central heating by utilizing the water / oil circulation of the recovery pipe. After the heat of the flue gas is taken away, the temperature in the flue can be reduced to the minimum, which means that the heat energy is recovered and the service life of the flue is greatly extended. The method of sending compressed air to the bottom of the flue through the pulse pipe in a pulse manner and blowing the accumulated ash in the flue to the end of the flue can ensure that there is no ash inside the flue. Blockage caused by long-term accumulation of ash in the flue is eliminated, the possibility of shutdown is reduced or eliminated, and production efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0020] Figure 1 is a cross-sectional view of the present invention;

[0021] Figure 2 is a cross-sectional view of a smoke tube of the present invention;

[0022] Figure 3 is a cross-sectional view of a smoke tube of the present invention;

[0023] Figure 4 It is a cross-sectional view of the smoke tube of the present invention.

[0024] The figure shows a first outer circular tube 1, a recovery pipe 2, a first inner circular tube 3, a receiving connecting pipe 4, a connecting pipe 5, a pulse valve interface 6, a nozzle 7, an outer shell 8, a pulse pipe fitting 9, and a supporting bracket 10. DETAILED DESCRIPTION

[0025] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0026] like Figures 1 to 4As shown, a variable diameter hollow flue that can remove dust accumulation and recycle the heat of flue gas, the variable diameter hollow flue is connected to the flue gas discharge port of the graphitization furnace, the variable diameter hollow flue is composed of a number of flue pipes with different diameters, and two adjacent flue pipes are connected in a fixed connection method, the fixed connection method is a socket-type plus pipe seamless welding connection method, in other embodiments, the fixed connection method can be a screw connection method. A pulse pipe fitting 9 is welded every 2 meters in the bottom area of ​​the variable diameter hollow flue, and in other embodiments, a pulse pipe fitting 9 is welded every 3 or 4 meters in the bottom area of ​​the variable diameter hollow flue. The outer shell 8 of the pulse pipe fitting 9 is welded to the outer wall of the variable diameter hollow flue to form a whole. The diameter of the flue pipe ranges from 350 to 1200 mm. In other embodiments, the diameter of the smoke pipe may range from 600 to 1600 mm, or from 350 to 1600 mm, or from 600 to 1200 mm. A support bracket 10 is also fixedly mounted on each smoke duct.

[0027] In other embodiments, the smoke pipe includes a first outer circular tube 1 and a first inner circular tube 3, wherein the inner circular tube 3 is arranged in the inner cavity of the first outer circular tube 1, and the height of the first inner circular tube 3 is the same as that of the first outer circular tube 1, and a plurality of recovery pipes 2 arranged in a circular array are arranged between the outer wall of the first inner circular tube 3 and the inner wall of the first outer circular tube 1, and each of the recovery pipes 2 is connected to the connecting pipe 5 by seamless welding or screw thread; a receiving connecting pipe 4 is fixedly installed on one end of the first inner circular tube 3. The first outer circular tube 1 is composed of an iron layer or an aluminum layer and an aluminum silicate wool layer. The first inner circular tube 3 is cast by acid-resistant and alkali-resistant refractory materials, and its wall thickness ranges from 25, 30mm, 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, and 100mm. The acid-resistant and alkali-resistant refractory materials are semi-mullite. In other embodiments, the acid-resistant and alkali-resistant refractory materials can be aluminum silicate or high-aluminum refractory materials. The recovery pipe 2 is a heat-resistant cast iron pipe or a stainless steel pipe. The inner cavity of the recovery pipe 2 is passed with a liquid for taking away the heat inside the variable-diameter hollow flue. The liquid is water. In other embodiments, the liquid is oil. In this embodiment, the heat-resistant cast iron pipe refers to a cast iron pipe that can be used at high temperatures and whose anti-oxidation or anti-growth performance meets the use requirements.

[0028] In other embodiments, a channel for compressed air to clean dust is provided in the middle of the pulse tube 9, and the diameter range of the channel is 20mm, 30mm, 40mm, and 50mm. A nozzle 7 is provided at one end of the pulse tube 9, and the nozzle 7 is located in the inner cavity of the variable diameter hollow flue. A pulse valve interface 6 is provided at the other end of the pulse tube 9, and the pulse tube 9 is wrapped with an outer shell 8 made of heat-resistant stainless steel; the pulse tube 9 is cast by acid-resistant, alkali-resistant and refractory materials, and its wall thickness ranges from 25mm, 30mm, 40mm, 50mm, 60mm, 70mm, and 80mm.

[0029] The variable diameter hollow flue of the present invention adopts a variable diameter structure, and its pipe diameter ranges from 350mm to 1600mm. The smaller pipe diameter can reduce the cost and increase the flue gas flow rate. The first inner layer circular tube of the present invention is cast with acid-resistant, alkali-resistant and refractory materials, and the casting thickness is 25-80mm. The recovery pipe is directly in contact with the refractory material to form a heat recovery system. Water or oil can pass through the recovery pipe, and the heat energy is recovered by water or oil circulation for power generation or central heating. A pulse pipe is welded every 2-4 meters in the bottom area of ​​the variable diameter hollow flue. The pipe is made of heat-resistant stainless steel as the outer shell, and the interior is cast with acid-resistant, alkali-resistant and refractory materials. A 20-50mm circular or square channel is reserved in the middle, and compressed air blows away the ash at the bottom of the flue through the channel.

[0030] It should be noted that, in this article, terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements.

[0031] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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 replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A variable diameter hollow flue capable of removing dust accumulation and recycling flue gas heat, characterized in that: The variable diameter hollow flue is composed of a plurality of flue pipes with different diameters, and two adjacent flue pipes are connected in a fixed connection manner; a pulse pipe is welded at intervals of 2 to 4 meters in the bottom area of ​​the variable diameter hollow flue, and the outer shell of the pulse pipe is welded to the outer wall of the variable diameter hollow flue to form a whole; The smoke pipe comprises a first outer circular tube and a first inner circular tube, wherein the inner circular tube is arranged in the inner cavity of the first outer circular tube, and the height of the first inner circular tube is the same as that of the first outer circular tube, and a plurality of recovery pipes arranged in a circular array are arranged between the outer wall of the first inner circular tube and the inner wall of the first outer circular tube, and each of the recovery pipes is connected to the connecting pipe by seamless welding or screw thread, and a receiving connecting pipe is fixedly installed on one end of the first inner circular tube; The recovery pipe is a heat-resistant cast iron pipe or a stainless steel pipe, and the inner cavity of the recovery pipe is filled with liquid for taking away the heat inside the variable diameter hollow flue, and the liquid is water or oil; A channel for compressed air to clean dust is arranged in the middle of the pulse pipe fitting, and the diameter range of the channel is 20~50mm. A nozzle is arranged at one end of the pulse pipe fitting, and the nozzle is located in the inner cavity of the variable diameter hollow flue. A pulse valve interface is arranged at the other end of the pulse pipe fitting. The pulse pipe fitting is wrapped with an outer shell made of heat-resistant stainless steel. The pulse pipe fitting is cast by acid-resistant, alkali-resistant and refractory materials, and its wall thickness ranges from 25~80mm.

2. The variable diameter hollow flue capable of removing dust accumulation and recycling flue gas heat according to claim 1 is characterized in that: The first outer circular tube is composed of an iron layer or an aluminum layer and an aluminum silicate wool layer.

3. The variable diameter hollow flue capable of removing dust accumulation and recycling flue gas heat according to claim 2 is characterized in that: The first inner layer circular tube is cast by acid-resistant, alkali-resistant and refractory materials, and its wall thickness ranges from 25 to 100 mm. The acid-resistant, alkali-resistant and refractory materials are semi-mullite, aluminum silicate or high-aluminum refractory materials.

4. The variable diameter hollow flue capable of removing dust accumulation and recycling flue gas heat according to claim 1 is characterized in that: The diameter of the smoke pipe ranges from 350-600 mm to 1200-1600 mm.

5. The variable diameter hollow flue capable of removing dust accumulation and recycling flue gas heat according to claim 1 is characterized in that: The fixed connection method includes a socket-and-spigot type plus a pipe seamless welding type or a screw-connected type.

6. The variable diameter hollow flue capable of removing dust accumulation and recycling flue gas heat according to claim 1 is characterized in that: The variable diameter hollow flue is connected to the flue gas discharge port of the graphitization furnace.

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