CN113418302B - Heat exchanger structure based on biomass hot blast stove is used - Google Patents

Abstract

The invention relates to the technical field of hot blast stoves, in particular to a heat exchanger structure for a biomass-based hot blast stove. The heat exchanger structure based on biomass hot-blast stove comprises a shell, an inner frame plate and a transfer hollow disc, wherein the inner frame plate is fixedly welded in the shell and is close to the inner top wall of the shell, a partition assembly is installed on the inner frame plate, the transfer hollow disc is fixedly welded on the inner bottom wall of the shell, and a first return stroke piece, a second return stroke piece and a third return stroke piece are installed between the transfer hollow disc and the inner frame plate. The three return members are arranged in the heat exchanger structure for the biomass hot blast stove, so that heat flow can flow in three strokes in the shell, the contact area with cold air flow blown by the fan is increased, the flow stroke of the heat flow is prolonged, and the heat exchange effect of the heat exchanger is enhanced.

Description

Heat exchanger structure based on biomass hot blast stove is used

Technical Field

The invention relates to the technical field of hot blast stoves, in particular to a heat exchanger structure for a biomass-based hot blast stove.

Background

The hot blast stove is a thermal power machine, is widely applied in China at the end of the 70 th century, and is an updated product of an electric heat source and a traditional steam power heat source in a plurality of industries. The hot blast stove has various kinds and full series, and is divided into hand burning and machine burning in a coal feeding mode, and is divided into coal, oil, gas stove and the like in a fuel type.

The biomass hot blast stove is a novel hot blast stove taking biomass fuel as fuel, and common biomass fuel such as straw, sawdust, bagasse, rice chaff and the like is formed into various organic matters through photosynthesis. In general, a biomass hot blast stove does not directly use, for example, straw or the like as fuel, but biomass fuel is essentially a processed product of straw or the like, and is in a granular physical form.

In order to enhance the heat utilization rate, the existing biomass hot-blast stove is additionally provided with a plurality of heat exchangers in a combustion chamber, and the heat exchangers for the existing biomass hot-blast stove are short in overall heat flow stroke, so that the exchange efficiency of hot air heat in the heat exchangers and cold air flow of a fan is reduced, and meanwhile, fine biomass floating in part of heat flow can flow out of a flow channel and be adsorbed in the heat exchangers, so that the heat exchange effect of the heat exchangers is further reduced.

Therefore, it is necessary to provide a new heat exchanger structure for biomass-based hot blast stoves to solve the above technical problems.

Disclosure of Invention

In order to solve the technical problems, the invention provides a heat exchanger structure for a biomass-based hot blast stove.

The heat exchanger structure for the biomass-based hot blast stove provided by the invention comprises the following components:

A housing;

The inner frame plate is fixedly welded in the shell and is close to the inner top wall of the shell, and the dividing assembly is arranged on the inner frame plate;

The transfer hollow disc is fixedly welded on the inner bottom wall of the shell, and a first return piece, a second return piece and a third return piece are arranged between the transfer hollow disc and the inner frame plate.

Preferably, the partition assembly comprises an arc plate and metal smoke filtering grids, the arc plate is fixedly embedded on the inner frame plate, the metal smoke filtering grids are fixedly embedded on the plate surfaces on two sides of the arc plate, and the arc plate divides a shell cavity on the upper portion of the inner frame plate into an air inlet arc cavity and a transfer arc cavity which are distributed front and back.

Preferably, the partition assembly further comprises two groups of cleaning pieces, the two groups of cleaning pieces are arranged on the inner frame plate and correspond to the two metal smoke filtering grids one by one, each cleaning piece comprises a rotating plate and cleaning steel wires, the rotating plates with the same specifications are fixedly arranged on the rotating shaft, the rotating shaft is rotatably arranged on the inner frame plate and coaxially arranged with the corresponding metal smoke filtering grids, and each cleaning steel wire is fixedly embedded on the outer wall of the rotating plate and is propped against the inner wall of the metal smoke filtering grid.

Preferably, a smoke dust material returning opening is formed in the inner frame plate corresponding to the metal smoke dust filtering grid in the air inlet arc-shaped cavity, the smoke dust material returning opening is communicated with a feeding opening of the dust containing box, the dust containing box is fixedly embedded at the bottom of the inner frame plate, and a dust discharging valve is arranged on the dust containing box.

Preferably, the first return member is a brass tube, one end of the brass tube is fixedly mounted on a mounting through hole formed in the transferring arc-shaped cavity, the other end of the brass tube extends into the transferring hollow disc, a plurality of groups of brass tubes are arranged, and the plurality of groups of brass tubes are distributed in a fan-shaped equidistant manner.

Preferably, the second return member comprises a communication center control column and a through pipe, wherein the communication center control column is fixedly arranged on the transportation hollow disc and is communicated with the transportation hollow disc, and a plurality of radial distribution through pipes are fixedly arranged in the communication center control column.

Preferably, the heating element is installed at the top of leading to well accuse post, carries out secondary heating to the hot air current that flows in the accuse post in leading to through heating element, heating element is including mounting box, annular metal pipe, prevent wind nozzle, electromagnetism fire maker and shunt tubes, mounting box fixed mounting is at the top of leading to well accuse post, just fixed mounting has annular metal pipe in the mounting box, fixed mounting has a plurality of annular distribution, downdip prevent wind nozzle on the interior pipe wall of annular metal pipe, just the centre of a circle department of annular metal pipe has the electromagnetism fire maker through frame fixed mounting, the equal fixed mounting of both sides diapire of mounting box has the shunt tubes.

Preferably, the third return member comprises a guide pipe, a fixing rod, a spiral plate and a connecting pipe, wherein the spiral plate is fixedly installed on the outer wall of the fixing rod, the spiral plate is arranged in the guide pipe and fixedly connected with the inner pipe wall of the guide pipe, and the connecting pipe is fixedly installed at the top of the guide pipe.

Preferably, the third return members are provided with two sides, and the two groups of the third return members are distributed on the two groups of the second return members, and the connecting pipes in the third return members are communicated with the shunt pipes at corresponding positions.

Preferably, two heat flow air inlet pipes are fixedly installed on the shell corresponding to the air inlet arc-shaped cavity, the two heat flow air inlet pipes are respectively opposite to the two metal smoke dust filtering grids, two heat flow air outlet pipes are installed on the shell, the two air outlet pipes are respectively communicated with the air outlets of the guide pipes in the two groups of third return members, an exhaust pipe and an air inlet pipe are fixedly installed on the front end surface and the rear end surface of the middle of the shell respectively, and the exhaust pipe and the air inlet pipe are positioned on the shell between the inner frame plate and the transferring hollow disc.

Compared with the related art, the heat exchanger structure for the biomass-based hot blast stove has the following beneficial effects:

1. the three return members are arranged in the shell, so that heat flow can flow in three strokes in the shell, the contact area of the heat flow with cold air blown by the fan is increased, the flow stroke of the heat flow is prolonged, and the heat exchange effect of the heat exchanger is enhanced;

2. According to the invention, the heating assembly is used for heating the air flow entering the third stroke part, so that on one hand, the subsequent heating of the cold air flow is enhanced, and on the other hand, the fire ring can be used for heating and burning the micro biomass floating in the heat flow, and the utilization of the biomass is improved.

Drawings

FIG. 1 is a schematic view of a heat exchanger structure for a biomass-based hot blast stove according to a preferred embodiment of the present invention;

FIG. 2 is a schematic view of the interior of the housing of FIG. 1;

FIG. 3 is a schematic view of the partition assembly of FIG. 2;

FIG. 4 is a schematic view of the configuration of the cleaning elements of the partition assembly of FIG. 2;

FIG. 5 is a schematic view of the mounting structure of the first return member shown in FIG. 2;

FIG. 6 is a schematic view of the second return member of FIG. 2;

FIG. 7 is a schematic view of the connection of the second return member and the heating assembly shown in FIG. 6;

Fig. 8 is a schematic structural view of the third return member shown in fig. 2.

Reference numerals in the drawings: 1. a housing; 2. an inner frame plate; 2a, an air inlet arc cavity; 2b, transferring the arc-shaped cavity; 2c, a smoke dust material returning port; 2d, mounting through holes; 3. transferring the hollow disc; 4. a segmentation component; 41. an arc-shaped plate; 42. a metal soot filtration grid; 43. a cleaning member; 431. a rotating plate; 432. cleaning the steel wire; 5. a dust accommodating box; 6. a first return member; 7. a second return member; 71. a central control column is communicated; 72. a through pipe; 8. a heating assembly; 81. a mounting box; 82. an annular metal tube; 83. a wind-proof nozzle; 84. an electromagnetic igniter; 85. a shunt; 9. a third return member; 91. a conduit; 92. a fixed rod; 93. a spiral plate; 94. a connecting pipe; 9a, a heat flow air inlet pipe; 9b, a heat flow exhaust pipe; 9c, an air inlet pipe; 9d, an exhaust pipe.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

Specific implementations of the invention are described in detail below in connection with specific embodiments.

Referring to fig. 1 to 8, a heat exchanger structure for a biomass-based hot blast stove according to an embodiment of the present invention includes:

A housing 1;

The inner frame plate 2 is fixedly welded in the shell 1 and is close to the inner top wall of the shell 1, and the inner frame plate 2 is provided with a dividing assembly 4;

The transfer hollow disc 3 is fixedly welded on the inner bottom wall of the shell 1, and a first return member 6, a second return member 7 and a third return member 9 are arranged between the transfer hollow disc 3 and the inner frame plate 2.

It should be noted that: the three return members arranged in the shell 1 enable heat flow to flow in three strokes in the shell 1, so that the contact area with cold air flow blown by the fan is increased, the flow stroke of the heat flow is prolonged, and the heat exchange effect of the heat exchanger is enhanced.

In the embodiment of the present invention, referring to fig. 2, 3 and 4, the partition assembly 4 includes an arc plate 41 and a metal smoke filtering grid 42, the arc plate 41 is fixedly embedded on the inner frame plate 2, the metal smoke filtering grids 42 are fixedly embedded on the plate surfaces on both sides of the arc plate 41, and the arc plate 41 divides the cavity of the housing 1 on the upper portion of the inner frame plate 2 into an air inlet arc cavity 2a and a transferring arc cavity 2b which are distributed front and back;

The partition assembly 4 further comprises two cleaning members 43, the cleaning members 43 are provided with two groups, the two groups of cleaning members 43 are installed on the inner frame plate 2 and correspond to the two metal smoke filtering grids 42 one by one, the cleaning members 43 comprise rotating plates 431 and cleaning steel wires 432, the rotating plates 431 with the same specifications are fixedly installed on rotating shafts, the rotating shafts are rotatably installed on the inner frame plate 2 and are coaxially arranged with the corresponding metal smoke filtering grids 42, cleaning steel wires 432 are fixedly embedded on the outer wall of each rotating plate 431 and abut against the inner walls of the cleaning steel wires 432 and smoke returning openings 2c are formed in the air inlet arc-shaped cavities 2a and correspond to the metal smoke filtering grids 42, the smoke returning openings 2c are communicated with feeding openings of the dust containing boxes 5, the dust containing boxes 5 are fixedly embedded at the bottoms of the inner frame plate 2, and dust discharging valves are installed on the dust containing boxes 5.

It should be noted that: the heat flow generated after the biomass of the hot blast stove is combusted enters the air inlet arc-shaped cavity 2a through the heat flow air inlet pipe 9a, and the heat flow in the air inlet arc-shaped cavity 2a enters the transferring arc-shaped cavity 2b after being purified and filtered through the metal smoke filtering grid 42, so that the dust and particle content in the heat flow flue gas is reduced;

Also to be described is: when the heat flow enters the air inlet arc-shaped cavity 2a, a rotating plate 431 on the rotating shaft can be blown to rotate, so that a cleaning steel wire 432 on the rotating plate 431 brushes the net surface on the outer side of the metal smoke filtering net 42, dust attached to the metal smoke filtering net 42 is brushed down and can fall into the dust accommodating box 5 through a dust material returning opening 2c, and the dust accommodating box is subsequently processed by staff;

Whereas in the present embodiment: in order to improve the cleanliness of the internal elements of the heat exchanger and enhance the heat exchange effect, a filtering device can be additionally arranged between the combustion air outlet of the hot blast stove and the hot flow air inlet pipe 9a, so that the filtering pressure of the metal smoke filtering grid 42 on smoke is reduced, and the service life of the internal elements of the heat exchanger is also ensured.

The two heat flow air inlet pipes 9a are fixedly installed on the shell 1 corresponding to the air inlet arc-shaped cavity 2a, the two heat flow air inlet pipes 9a are respectively opposite to the two metal smoke dust filtering grids 42, the two heat flow air outlet pipes 9b are installed on the shell 1, the two air outlet pipes 9b are respectively communicated with air outlets of the guide pipes 91 in the two groups of third return members 9, an air outlet pipe 9d and an air inlet pipe 9c are respectively fixedly installed on the front end face and the rear end face of the middle of the shell 1, and the air outlet pipe 9d and the air inlet pipe 9c are positioned on the shell 1 between the inner frame plate 2 and the transferring hollow disc 3.

It should be noted that: the hot-flow air inlet pipe 9a is communicated with a combustion air outlet of the hot blast stove, the hot-flow air outlet pipe 9b is communicated with a hot-flow recovery pipe of the hot blast stove, the air inlet pipe 9c is communicated with an air outlet flow passage of a fan, the air outlet pipe 9d is communicated with an air outlet of the hot blast stove, meanwhile, the feed inlet of the annular metal pipe 82 is communicated with a guide pipe, and the other end of the guide pipe is communicated with a gas pipe or a gas pipe, so that the pipeline connection of the whole heat exchanger is completed;

Whereas in the present embodiment: the heat flow exhaust pipe 9b can be communicated with the combustion hearth of the hot blast stove, so that heat flow subjected to heat exchange blows into the combustion hearth of the hot blast stove, the combustion effect of biomass in the hearth is enhanced, and the biomass combustion is promoted to be more sufficient.

In the embodiment of the present invention, referring to fig. 2, 5, 6 and 8, the first return member 6 is a brass tube, one end of the brass tube is fixedly installed on an installation through hole 2d formed in the transferring arc cavity 2b, and the other end of the brass tube extends into the transferring hollow disc 3, the brass tube is provided with a plurality of groups, and the plurality of groups of brass tubes are distributed in fan-shaped equidistant manner, the second return member 7 comprises a communicating central control column 71 and a through tube 72, the communicating central control column 71 is fixedly installed on the transferring hollow disc 3 and is communicated with the transferring hollow disc 3, a plurality of radial distribution through tubes 72 are fixedly installed in the communicating central control column 71, the third return member 9 comprises a guide tube 91, a fixing rod 92, a spiral plate 93 and a connecting tube 94, the spiral plate 93 is fixedly installed on the outer wall of the fixing rod 92, the spiral plate 93 is arranged in the guide tube 91 and is fixedly connected with the inner tube wall of the guide tube 91, the top of the guide tube 91 is fixedly installed with the connecting tube 94, the third return member 9 is provided with the second return member 9, and the second return member 7 is communicated with the second return member 7 via the second return member 8.

It should be noted that: the purified heat flow flows back into the transferring hollow disc 3 through the brass pipe, flows into the communicating central control column 71 from the transferring hollow disc 3 and finally flows into the guide pipe 91 through the heating component 8, so that the heat flow flows in three strokes in the shell 1, the contact area with cold air flow blown by the fan is increased, the flow stroke of the heat flow is prolonged, and the heat exchange effect of the heat exchanger is enhanced;

Also to be described is: because the through pipe 72 is embedded in the communication center control column 71, the flowing stroke of heat flow in the communication center control column 71 is improved, and meanwhile, the whole heat exchange area of the communication center control column 71 is increased, so that the heat exchange effect is further improved;

Also to be described is: because the spiral plate 93 is arranged in the conduit 91, the flow stroke of the heat flow in the conduit 91 is also prolonged, and meanwhile, the two groups of conduits 91 can split the heat flow in the communication central control column 71, so that on one hand, the flow speed of the heat flow is reduced, and on the other hand, when a group of third return members 9 are damaged, the whole-bus heat exchanger can still work normally.

In the embodiment of the present invention, referring to fig. 2 and 7, a heating component 8 is installed at the top of the through center control column 71, the heating component 8 is used for performing secondary heating on the hot air flowing in the through center control column 71, the heating component 8 includes a mounting box 81, an annular metal tube 82, a wind-proof nozzle 83, an electromagnetic fire lighter 84 and a shunt tube 85, the mounting box 81 is fixedly installed at the top of the through center control column 71, the annular metal tube 82 is fixedly installed in the mounting box 81, a plurality of wind-proof nozzles 83 which are annularly distributed and incline inwards are fixedly installed on the inner tube wall of the annular metal tube 82, the electromagnetic fire lighter 84 is fixedly installed at the center of the annular metal tube 82 through a frame, the shunt tubes 85 are fixedly installed at the bottom walls of the two sides of the mounting box 81, and the connecting tube 94 in the third return member 9 is communicated with the shunt tube 85 at the corresponding position.

It should be noted that: after the gas pipe or the gas pipe is opened, the electromagnetic igniter 84 is opened, so that the windproof nozzle 83 on the annular metal pipe 82 forms an annular fire ring, the flowing heat flow is subjected to secondary heating, and as the heat flow entering the installation box 81 is subjected to effective heat exchange in the two former strokes, the heat quantity of the heat flow is reduced more than that of the heat flow in the two former strokes, on one hand, the subsequent heating of cold air flow is enhanced by heating the heat flow through the heating component 8, and on the other hand, the fire ring can heat and burn micro biomass floating in the heat flow, so that the utilization of biomass is improved.

The working principle of the heat exchanger structure for the biomass-based hot blast stove provided by the invention is as follows:

The shell 1 is arranged in a heat exchange chamber of the hot blast stove, the heat flow air inlet pipe 9a on the shell 1 is communicated with the combustion air outlet of the hot blast stove, the heat flow air outlet pipe 9b is communicated with the combustion hearth of the hot blast stove, so that heat flow after heat exchange is blown into the combustion hearth of the hot blast stove, the combustion effect of biomass in the hearth is enhanced, the biomass combustion is promoted to be more sufficient, the air inlet pipe 9c is communicated with the air outlet flow passage of a fan in the hot blast stove, the air outlet pipe 9d is communicated with the air outlet of the hot blast stove, the air inlet of the annular metal pipe 82 is communicated with a conduit, the other end of the conduit is communicated with a gas pipe or the gas pipe, the pipeline connection of the whole heat exchanger is completed, the heat flow generated after the biomass combustion of the hot blast stove enters the air inlet arc cavity 2a through the heat flow air inlet pipe 9a, and the heat flow in the air inlet arc cavity 2a enters the transferring arc cavity 2b after being purified and filtered through the metal smoke filtering grid 42, therefore, the dust and particle content in the hot flow flue gas is reduced, and in order to improve the cleanliness of the internal elements of the heat exchanger and enhance the heat exchange effect, a filtering device can be additionally arranged between the combustion air outlet of the hot blast stove and the hot flow air inlet pipe 9a, so that the filtering pressure of the metal smoke filtering grid 42 on smoke is reduced, the service life of the internal elements of the heat exchanger is also ensured, the purified hot flow flows back into the transferring hollow disc 3 through a brass tube, flows into the communicating central control column 71 through the transferring hollow disc 3 and finally flows into the guide pipe 91 through the heating component 8, therefore, the hot flow flows in three strokes in the shell 1, not only the contact area with cold air blown by a fan is increased, but also the flow stroke of the hot flow is prolonged, the heat exchange effect of the heat exchanger is enhanced, and the communicating central control column 71 is embedded with the through pipe 72, therefore, the flow stroke of the heat flow in the communicating central control column 71 is improved, meanwhile, the whole heat exchange area of the communicating central control column 71 is increased, the heat exchange effect is further improved, the spiral plate 93 is arranged in the guide pipe 91, so that the flow stroke of the heat flow in the guide pipe 91 is also prolonged, meanwhile, two groups of guide pipes 91 can split the heat flow in the communicating central control column 71, on one hand, the flow speed of the heat flow is reduced, on the other hand, when a group of third return members 9 are damaged, the whole-brother heat exchanger can work normally, the electromagnetic fire generator 84 is opened after the gas pipe or the gas pipe is opened, so that the wind-proof nozzle 83 on the annular metal pipe 82 forms an annular fire ring, the flowing heat flow is secondarily heated, and the heat flow entering the installation box 81 has effectively exchanged heat in the two previous strokes, so that the heat per se is reduced compared with the two previous strokes, on the one hand, the subsequent heating of the cold air flow is enhanced through the heating component 8, on the other hand, the micro biomass floating in the heat flow can be heated and combusted, and the utilization of biomass is improved.

The foregoing description is only illustrative of the present invention and is not intended to limit the scope of the invention, and all equivalent structures or equivalent processes or direct or indirect application in other related technical fields are included in the scope of the present invention.

Claims (4)

1. Heat exchanger structure based on living beings hot-blast furnace is used, its characterized in that includes:

A housing (1);

The inner frame plate (2), inner frame plate (2) fixed welding is in casing (1) and is close to the inner roof of casing (1), just install on inner frame plate (2) and cut apart subassembly (4), cut apart subassembly (4) including arc (41) and metal smoke and dust filtration net (42), arc (41) fixed gomphosis on inner frame plate (2), just all fixed gomphosis has metal smoke and dust filtration net (42) on the face of arc (41) both sides, arc (41) divide into inlet arc chamber (2 a) and the transportation arc chamber (2 b) that distribute around with casing (1) cavity of inner frame plate (2) top portion, cut apart subassembly (4) still include cleaning piece (43), cleaning piece (43) are provided with two sets of, and two sets of cleaning piece (43) install on inner frame plate (2) and with two piece metal smoke and dust filtration net (42) one-to-one, cleaning piece (43) include rotating plate (431) and cleaning piece (432), rotating plate (431) the same specification on the same rotating plate (431) and installing on a plurality of coaxial rotating plates (431) and rotating on the coaxial wire (432) and (432) of fixed connection on each rotating plate (431) and rotating plate (2), and is propped against the inner wall of the metal smoke filtering grid (42) and the cleaning steel wires (432);

The transporting hollow disc (3), the transporting hollow disc (3) is fixedly welded on the inner bottom wall of the shell (1), a first return piece (6), a second return piece (7) and a third return piece (9) are arranged between the transporting hollow disc (3) and the inner frame plate (2), the first return piece (6) is a brass tube, one end of the brass tube is fixedly arranged on an installation through hole (2 d) formed in the transporting arc-shaped cavity (2 b), the other end of the brass tube extends into the transporting hollow disc (3), the brass tube is provided with a plurality of groups, the brass tubes are distributed in a fan-shaped manner, the second return piece (7) comprises a communicating central control column (71) and a through tube (72), the communicating central control column (71) is fixedly arranged on the transporting hollow disc (3) and is communicated with the transporting hollow disc (3), a plurality of radial distribution through tubes (72) are fixedly arranged in the communicating central control column (71), the third piece (9) comprises a plurality of guide tubes (92), a spiral tube (91) and a spiral tube (93) are fixedly arranged on the inner wall (91) and the inner wall (93) of the connecting tube (93), a connecting pipe (94) is fixedly arranged at the top of the guide pipe (91);

The utility model discloses a hot air heater, including installation box (81), annular metal pipe (82), prevent wind nozzle (83), electromagnetism fire ware (84) and shunt tubes (85), install box (81) fixed mounting at the top of leading to well accuse post (71), just install annular metal pipe (82) in install box (81), fixed mounting has a plurality of annular distribution on the interior pipe wall of annular metal pipe (82), prevent wind nozzle (83) of downdip, just the centre of a circle department of annular metal pipe (82) has electromagnetism fire ware (84) through frame fixed mounting, the both sides diapire of install box (81) all fixed mounting shunt tubes (85).

2. The heat exchanger structure for biomass-based hot blast stove according to claim 1, wherein a smoke return port (2 c) is formed in an inner frame plate (2) corresponding to the metal smoke filtering grid (42) in the air inlet arc-shaped cavity (2 a), the smoke return port (2 c) is communicated with a feed port of a dust accommodating box (5), the dust accommodating box (5) is fixedly embedded at the bottom of the inner frame plate (2), and a dust exhaust valve is arranged on the dust accommodating box (5).

3. The heat exchanger structure for biomass based hot blast stoves according to claim 1, wherein the third return members (9) are provided in two groups, and the two groups of third return members (9) are distributed on both sides of the second return member (7), and the connecting pipes (94) in the third return members (9) are communicated with the shunt pipes (85) at corresponding positions.

4. The heat exchanger structure for the biomass-based hot blast stove according to claim 1, wherein two heat flow air inlet pipes (9 a) are fixedly installed on a shell (1) corresponding to the air inlet arc-shaped cavity (2 a), the two heat flow air inlet pipes (9 a) are respectively opposite to two metal smoke filtering grids (42), two heat flow air outlet pipes (9 b) are installed on the shell (1), the two air outlet pipes (9 b) are respectively communicated with air outlets of guide pipes (91) in two groups of third return members (9), an exhaust pipe (9 d) and an air inlet pipe (9 c) are fixedly installed on front and rear end surfaces of the middle of the shell (1), and the exhaust pipe (9 d) and the air inlet pipe (9 c) are located on the shell (1) between the inner frame plate (2) and the transferring hollow disc (3).