CN210505609U - Roasting system - Google Patents

Abstract

A roasting system belongs to the technical field of alumina roasting systems. Including consecutive preheating device, calcination device and cooling device, its characterized in that: the roasting device comprises a fluidized bed roasting furnace (14), a preheating device is communicated with a feeding pipe (35) of the fluidized bed roasting furnace (14), a cooling device is communicated with a discharging pipe (43) of the fluidized bed roasting furnace (14), a retention groove (44) is arranged in the fluidized bed roasting furnace (14), the retention groove (44) is arranged between the feeding pipe (35) and the discharging pipe (43) of the fluidized bed roasting furnace (14), a plurality of partition plates (45) are arranged in the retention groove (44) at intervals along the material flowing direction, the retention groove (44) is divided into a plurality of retention bins with upper side openings, and a fluidizing air distribution device at the bottom of the fluidized bed roasting furnace (14) is communicated with the retention bins. The material of the roasting system advances from bin to bin in a bin-by-bin overflow mode in the staying tank, so that the expected staying time target is realized.

Description

Roasting system

Technical Field

A roasting system belongs to the technical field of alumina roasting systems.

Background

The roasting process of the aluminum hydroxide is the last procedure in the production process of the aluminum oxide and is an important link for determining the yield and the quality of the aluminum oxide, the energy consumption in the production process and the pollutant discharge. At present, the gas suspension roasting technology of Danish Smith company is widely adopted in the roasting technology of aluminum hydroxide in China. In a gaseous suspension roasting furnace, natural gas or coal gas and air preheated to 700-1000 ℃ are combusted to generate high-temperature flue gas, the high-temperature flue gas heats an aluminum hydroxide material to complete the processes of dehydration and partial crystal phase transformation, aluminum oxide is generated, and the aluminum oxide is cooled in multiple stages to finally form a qualified aluminum oxide product. The gas suspension roasting technology has the advantages of high productivity, convenient start and stop, good product quality and the like. The roasting process of the aluminum hydroxide goes through three development stages of the traditional rotary kiln process, the improved rotary kiln process and the fluidized roasting process. Compared with a rotary kiln, the fluidized roasting process has obvious advantages that: the heat efficiency is high, and the heat consumption is low; the product quality is good; the investment is low; the equipment is simple, the service life is long, and the maintenance cost is low; has low environmental pollution. The fluidization device is rapidly and widely applied to the production of alumina.

With the expansion of the market capacity of alumina products for non-metallurgical use, the demand of alumina products with specific requirements is increased year by year, and for specific products with the conversion rate of α -alumina being 40-70%, the production goal cannot be realized by adopting two fluidized roasting furnaces, namely the current circulating fluidized bed roasting furnace or the gas suspension roasting furnace, and a new device invention is urgently needed to meet the product demand.

Disclosure of Invention

The to-be-solved technical problem of the utility model is: overcomes the defects of the prior art, and provides a roasting system which can accurately control the retention time so as to ensure the conversion rate of specific products.

The utility model provides a technical scheme that its technical problem adopted is: this roasting system, including consecutive preheating device, roasting equipment and cooling device, its characterized in that: the roasting device comprises a fluidized bed roasting furnace, a preheating device is communicated with a feeding pipe of the fluidized bed roasting furnace, a cooling device is communicated with a discharging pipe of the fluidized bed roasting furnace, a staying groove is arranged in the fluidized bed roasting furnace and is arranged between the feeding pipe and the discharging pipe of the fluidized bed roasting furnace, a plurality of partition plates are arranged in the staying groove at intervals along the material flowing direction and divide the staying groove into a plurality of staying bins with upper sides open, and a fluidized air distribution device at the bottom of the fluidized bed roasting furnace is communicated with the staying bins.

Preferably, the bottom of each stopping bin is provided with a plurality of air caps at intervals, and each air cap is communicated with the fluidized air distribution device.

Preferably, the roasting device further comprises a heating furnace, an input port of the heating furnace is communicated with the preheating device, and an output port of the heating furnace is communicated with the feeding pipe.

Preferably, the preheating device comprises a first-stage preheater and a second-stage preheater, a discharge port of the first-stage preheater is communicated with a feed port of the second-stage preheater, a discharge port of the second-stage preheater is communicated with a feed pipe of the fluidized bed roasting furnace, an air inlet of the second-stage preheater is communicated with an air outlet cylinder of the fluidized bed roasting furnace, and an air outlet of the second-stage preheater is communicated with an air inlet of the first-stage preheater.

Preferably, the cooling device comprises an air cooling device and a water cooling device which are arranged in series, the discharge pipe of the fluidized bed roasting furnace is communicated with the air cooling device, and the water cooling device is connected with a material output pipe.

Preferably, the air cooling device comprises air coolers, the air coolers are connected in series to form multiple stages, and the air coolers are connected with cooler fans.

Preferably, the water cooling device is a fluidized bed cooler, a heat exchange coil is arranged in the fluidized bed cooler, and a water inlet of the heat exchange coil is connected with a circulating water pump.

Preferably, two discharging pipes of the fluidized bed roasting furnace are arranged at intervals in the height direction.

Compared with the prior art, the utility model discloses the beneficial effect who has is:

1. the preheating device of the roasting system can preheat materials, the roasting device can enable the materials to reach the roasting temperature quickly, and the cooling device can cool the roasted materials, so that qualified products are produced, a plurality of stopping bins are separated into the stopping slots through partition plates, the materials advance one by one in the stopping slots in a bin-by-bin overflow mode, and therefore the expected stopping time target is achieved, the preheating device can be used for the roasting system with controllable α -alumina conversion rate, the α -alumina conversion rate is adjustable and controllable within the range of 5% -95%, and the preheating device can be suitable for the powder roasting industry with few impurities and no molten state appearance through targeted system design.

2. The bottom of each staying bin is provided with a plurality of air caps, so that the materials in each staying bin are in a dynamic flowing state, the materials flow into the next staying bin in an overflowing mode, and the uniform roasting of the materials is ensured.

3. The heating furnace can quickly heat the materials to a specified temperature, the fluidized bed roasting furnace can carry out long-time heat preservation roasting on the heated materials, the conversion rate of the product is high, and the conversion is stable.

4. The material is gradually heated in the preheater and the crystal water is partially removed by means of a two-stage preheater.

5. The materials are cooled step by step through the air cooling device and the water cooling device, and the crystal phase transformation in the material cooling process is avoided.

6. Through setting up many discharging pipes that the height is different, realize the target of material residence time segmentation control, enlarge the application scope of equipment.

Drawings

FIG. 1 is a schematic diagram of a firing system.

Fig. 2 is a schematic front view of a fluidized bed roaster.

Fig. 3 is a schematic sectional view in the direction of a-a in fig. 2.

FIG. 4 is a schematic sectional front view of the retention tank.

In the figure: 1. the system comprises a belt weigher 2, a feeding machine 3, a dryer 4, a dryer separator 5, a cyclone dust collector 6, a bag-type dust collector 7, an exhaust fan 8, a chimney 9, a primary preheater 10, a secondary preheater 11, a heating furnace separator 12, a heating furnace 13, a roasting furnace separator 14, a fluidized bed roasting furnace 15, a four-stage air cooler 16, a three-stage air cooler 17, a two-stage air cooler 18, a primary air cooler 19, an air cooler dust collector 20, a fluidized bed cooler dust collector 21, a fluidized bed cooler 22, a circulating water pump 23, a fluidized bed cooler fan 24, an air cooler fan 25, a roasting furnace fluidizing fan 26, a pressurizing fan 27, a separator discharge valve 28, a roasting furnace discharge valve 29, a wind box 30, a material output pipe 31, a water inlet pipe 32, a water return pipe 33, a material outlet pipe 31, a material, The device comprises an air outlet cylinder 34, a roasting furnace main body 35, a feeding pipe 36, a spring hanger 37, an air cap 38, an air distribution pipe 39, a manhole 40, a gas spray gun 41, a temperature probe 42, a pressure probe 43, a discharging pipe 44, a staying groove 45 and a partition plate.

Detailed Description

Fig. 1 to 4 are preferred embodiments of the present invention, and the present invention will be further explained with reference to fig. 1 to 4.

A roasting system comprises a preheating device, a roasting device and a cooling device which are connected in sequence, wherein the roasting device comprises a fluidized bed roasting furnace 14, the preheating device is communicated with a feeding pipe 35 of the fluidized bed roasting furnace 14, the cooling device is communicated with a discharging pipe 43 of the fluidized bed roasting furnace 14, a staying groove 44 is arranged in the fluidized bed roasting furnace 14, the staying groove 44 is arranged between the feeding pipe 35 and the discharging pipe 43 of the fluidized bed roasting furnace 14, a plurality of partition plates 45 are arranged in the staying groove 44 at intervals along the material flowing direction and divides the staying groove 44 into a plurality of staying bins with open upper sides, and a fluidizing air distribution device at the bottom of the fluidized bed roasting furnace 14 is communicated with the staying bins at the same time.

The present invention is further described with reference to specific embodiments, however, it will be understood by those skilled in the art that the detailed description given herein with respect to the drawings is for better explanation and that the present invention is necessarily to be construed as limited to those embodiments, and equivalents or common means thereof will not be described in detail but will fall within the scope of the present application.

Specifically, the method comprises the following steps: as shown in fig. 1: the input of preheating device is provided with metering device, and metering device is belt weigher 1, and 1 level setting of belt weigher is provided with feeding machine 2 between belt weigher 1 and preheating device's the input, and in this embodiment, feeding machine 2 is the screw feeding machine, and feeding machine 2's input is linked together with belt weigher 1's output, and feeding machine 2's output is linked together with preheating device's input to accurate interpolation material.

A dryer 3 is arranged between the feeding machine 2 and the preheating device, a feed inlet of the dryer 3 is communicated with an output end of the feeding machine 2, and a discharge outlet of the dryer 3 is communicated with an input end of the preheating device, so that the drying of the materials is realized. In the present embodiment, the dryer 3 is a venturi dryer.

The air outlet of the dryer 3 is sequentially connected with a dryer separator 4, a cyclone dust collector 5, a bag-type dust collector 6 and a chimney 8, the air outlet of the dryer 3 is communicated with the input port of the dryer separator 4, the air outlet of the dryer separator 4 is communicated with the input port of the cyclone dust collector 5, the air outlet of the cyclone dust collector 5 is communicated with the input port of the bag-type dust collector 6, the air outlet of the bag-type dust collector 6 is communicated with the chimney 8, and an exhaust fan 7 is arranged between the air outlet of the bag-type dust collector 6 and the chimney 8.

The preheating device comprises a first-stage preheater 9 and a second-stage preheater 10, a discharge port of the dryer 3 is communicated with an input port of the first-stage preheater 9, a discharge port of the first-stage preheater 9 is communicated with a feed port of the second-stage preheater 10, an air outlet of the second-stage preheater 10 is communicated with an air inlet of the first-stage preheater 9, and an air outlet of the first-stage preheater 9 is communicated with an air inlet of the dryer 3. The discharge port of the dryer separator 4 is also communicated with the feed port of the primary preheater 9.

The roasting device comprises a heating furnace 12 and a fluidized bed roasting furnace 14, a discharge port of the heating furnace 12 is connected with a heating furnace separator 11, a discharge port of the fluidized bed roasting furnace 14 is connected with a roasting furnace separator 13, a feed port of the heating furnace 12 is communicated with a discharge port of a secondary preheater 10, a discharge port of the heating furnace 12 is communicated with an input port of the heating furnace separator 11, a discharge port of the heating furnace separator 11 is communicated with a feed pipe 35 of the fluidized bed roasting furnace 14, a discharge port of the fluidized bed roasting furnace 14 is communicated with an input port of the roasting furnace separator 13, and a discharge pipe 43 of the. A separator discharge valve 27 is arranged between the discharge hole of the heating furnace separator 11 and the feed hole of the fluidized bed roasting furnace 14, and a roasting furnace discharge valve 28 is arranged between the discharge hole of the fluidized bed roasting furnace 14 and the cooling device. The discharge hole of the cyclone dust collector 5 is also communicated with the feed inlet of the heating furnace 12, and the discharge hole of the bag-type dust collector 6 is also communicated with the feed pipe 35 of the fluidized bed roasting furnace 14.

An air outlet cylinder 33 of the fluidized bed roasting furnace 14 is also communicated with an input port of the roasting furnace separator 13, an air outlet of the roasting furnace separator 13 is communicated with an air inlet of the heating furnace 12, an air outlet of the heating furnace 12 is also communicated with an input port of the heating furnace separator 11, and an air outlet of the heating furnace separator 11 is communicated with an air inlet of the secondary preheater 10.

An air box 29 is arranged at the lower side of the fluidized bed roasting furnace 14, and the upper side of the air box 29 is communicated with the fluidized bed roasting furnace 14 through a fluidized air distribution device. The gas spray gun 40 of the fluidized bed roasting furnace 14 is connected with a booster fan 26, and is connected with a gas pipe through the booster fan 26. A roaster fluidization fan 25 is connected to the bottom of the wind box 29, and the output port of the roaster fluidization fan 25 is in communication with both the bottom of the wind box 29 and the roaster discharge valve 28, and is in communication with the bottom of the fluidized bed roaster 14 through the roaster discharge valve 28, so as to provide sufficient oxygen for combustion of the fuel gas.

The cooling device comprises an air cooling device and a water cooling device which are arranged in series, the air cooling device comprises a multi-stage air cooler which is arranged in series, and the air cooler is further connected with an air cooler dust remover 19 and an air cooler fan 24. In the embodiment, the air coolers are provided with four stages, namely a primary air cooler 18, a secondary air cooler 17, a tertiary air cooler 16 and a quaternary air cooler 15, a discharge pipe 43 of the fluidized bed roasting furnace 14 is communicated with a feed inlet of the primary air cooler 18 through a roasting furnace discharge valve 28, a discharge outlet of the primary air cooler 18 is communicated with a feed inlet of the secondary air cooler 17, a discharge outlet of the secondary air cooler 17 is communicated with a feed inlet of the tertiary air cooler 16, a discharge outlet of the tertiary air cooler 16 is communicated with a feed inlet of the quaternary air cooler 15, and a discharge outlet of the quaternary air cooler 15 is communicated with a water cooling device. An air outlet of the fan 24 of the air cooler is communicated with an air inlet of the fourth-stage air cooler 15, an air outlet of the fourth-stage air cooler 15 is communicated with an air inlet of the third-stage air cooler 16, an air outlet of the third-stage air cooler 16 is communicated with an air inlet of the second-stage air cooler 17, an air outlet of the second-stage air cooler 17 is communicated with an air inlet of the first-stage air cooler 18, an air outlet of the first-stage air cooler 18 is communicated with an input port of the dust remover 19 of the air cooler, and an air outlet of the dust remover 19 of the air cooler is communicated with an air inlet of the heating furnace 12.

The water cooling device is a fluidized bed cooler 21, the fluidized bed cooler 21 is also connected with a fluidized bed cooler dust remover 20, a feed inlet of the fluidized bed cooler dust remover 20 is communicated with a discharge outlet of the four-stage air cooler 15, a discharge outlet of the fluidized bed cooler dust remover 20 is connected with a material output pipe 30, an air outlet of the fluidized bed cooler 21 is communicated with an input port of the fluidized bed cooler dust remover 20, an air inlet of the fluidized bed cooler 21 is connected with a fluidized bed cooler fan 23, and a discharge outlet of the fluidized bed cooler dust remover 20 is also communicated with the material output pipe 30.

A heat exchange coil is arranged in the fluidized bed cooler 21, a water inlet pipe 31 is connected to a water inlet of the heat exchange coil, a water return pipe 32 is connected to a water outlet of the heat exchange coil, and a circulating water pump 22 is arranged on the water inlet pipe 31.

As shown in fig. 2 to 3, the fluidized bed roasting furnace 14 includes a roasting furnace main body 34, a fluidized air distribution device disposed at the lower side of the roasting furnace main body 34, and a heating device disposed at the bottom of the roasting furnace main body 34, the heating device is disposed at the upper side of the fluidized air distribution device, a retention tank 44 is disposed in the roasting furnace main body 34, the retention tank 44 is disposed between the feeding pipe 35 and the discharging cylinder 43 of the roasting furnace main body 34, a plurality of partition plates 45 are disposed in the retention tank 44 at intervals along the material flowing direction, and the retention tank 44 is divided into a plurality of retention bins with open upper sides, and the lower portion of each retention bin is communicated with the fluidized air distribution device.

The roasting furnace main body 34 is vertically arranged, a vertical air outlet cylinder 33 is arranged in the middle of the upper side of the roasting furnace main body 34, the lower end of the air outlet cylinder 33 is communicated with the inner cavity of the roasting furnace main body 34, the middle of the left side of the roasting furnace main body 34 is connected with an inlet pipe 35, the middle of the right side of the roasting furnace main body 34 is connected with a discharge pipe 43, and the roasting furnace main body 34 is provided with three furnace chambers side by side along the direction from the inlet pipe 35 to the discharge pipe 43, namely.

The middle part of each furnace chamber is provided with a manhole 39 for maintenance, the bottom of each furnace chamber is provided with a fluidized air distribution device, and the two sides of each fluidized air distribution device are connected with the roasting furnace main body 34 through spring hangers 36. The lower part of each furnace chamber is connected with a heating device which is arranged on the upper side of the corresponding fluidized air distribution device. The lower part of each furnace chamber is also provided with a temperature probe 41 and a pressure probe 42 which are respectively used for detecting the temperature and the pressure of the furnace chamber, and the detection is convenient.

An air box 29 is arranged at the lower side of each furnace chamber, the fluidized air distribution device is arranged in the corresponding air box 29, and the fluidized air distribution device comprises an air distribution plate arranged at the upper side of the air box 29 and arranged on a main body 34 of the roasting furnace through a spring hanger 36.

The middle part of the left side of the roasting furnace main body 34 is provided with a feeding pipe 35, the feeding pipe 35 is inclined gradually downwards from left to right, and the lower end of the feeding pipe 35 is communicated with the inner cavity of the roasting furnace main body 34, so that materials can be conveniently added into the roasting furnace main body 34. The discharging pipe 43 is connected to the middle part of the right side of the roasting furnace main body 34, the discharging pipes 43 are sequentially arranged from top to bottom, in this embodiment, two discharging pipes 43 are arranged from top to bottom, so that the aim of segmented control of material residence time can be achieved, and the application range of the equipment is expanded.

As shown in fig. 4: the staying groove 44 is arranged in the roasting furnace main body 34, the staying groove 44 is arranged between the feeding pipe 35 and the discharging pipe 43 of the roasting furnace main body 34, the staying groove 44 is a groove body with an open upper side, and the staying groove 44 and the inner wall of the roasting furnace main body 34 enclose a box body with an open upper side. Be provided with baffle 45 in the groove 44 that stops, the vertical setting of baffle 45, baffle 45 are provided with the polylith along the direction interval by inlet pipe 35 to discharging pipe 43 to will stop the groove 44 and separate into a plurality of storehouses that stop that set up side by side. The partition 45 is detachably connected to the staying tank 44 so as to facilitate adjustment of the staying time of the materials in each staying bin.

Each lateral part that stops the storehouse all is provided with a plurality of hoods 37, and in this embodiment, each lateral part that stops the storehouse all is provided with three hoods 37, and the grid plate is linked together through grid 38 and hood 37, and grid 38 and hood 37 one-to-one to can make the material that each stops in the storehouse be in the mobile state, can stop the storehouse overflow downwards through the mode of overflow.

A production method for producing α -alumina by using the roasting system comprises the following steps:

step 1), feeding the weighed materials into a preheating device to complete removal of physical water, then heating to 650-750 ℃, and partially removing crystal water;

the method comprises the steps that aluminum hydroxide serving as a material is metered by a belt scale 1 and then enters a feeding machine 2, the aluminum hydroxide is fed into a dryer through the feeding machine to be dried, the aluminum hydroxide is heated in the dryer 3 to remove physical water, then the aluminum hydroxide enters a primary preheater 9 and a secondary preheater 10 to be heated to 650-750 ℃, the material is partially removed from crystal water in the primary preheater 9 and the secondary preheater 10, tail gas is discharged through a chimney 8 after being dedusted by a dryer separator 4, a cyclone dust collector 5 and a bag-type dust collector 6 in sequence, the temperature of the tail gas discharged through the chimney 8 is reduced to be below 200 ℃, and dust collection ash captured by the dryer separator 4, the cyclone dust collector 5 and the bag-type dust collector 6 returns to the primary preheater 9.

The preheated material in the step 2) enters a fluidized bed roasting furnace 14 for roasting, wherein the roasting temperature is 1150-1250 ℃, and the roasting time is 1.5-2 h;

the preheated material firstly enters a heating furnace 12, is heated to 1200-1300 ℃ in the heating furnace 12 in a suspension state for 10-20 s, and then is sent into a fluidized bed roasting furnace 14, the material is roasted in the fluidized bed roasting furnace 14 at 1150-1250 ℃ for 1.5-2 h, so that the conversion of the crystal form of alumina is completed, most of natural gas is combusted in the heating furnace 12, and a small part of natural gas is combusted in the fluidized bed roasting furnace 14 to be used as heat supplement. The material retention time can be controlled by adjusting the height of the partition plate 45 of the fluidized bed roasting furnace 14, and the furnace temperature of the fluidized bed roasting furnace 14 can be controlled by adjusting the natural gas amount of the gas spray gun 40. The fluidized bed roasting furnace 14 takes air as fluidized air, and the air is preheated to 600 ℃ and enters the furnace. The tail gas of the fluidized bed roasting furnace 14 enters the heating furnace 12 after being dedusted by the roasting furnace separator 13.

Cooling the roasted material in the step 3) in a cooling device to obtain α -alumina;

the roasted material is sequentially cooled by a primary air cooler 18, a secondary air cooler 17, a tertiary air cooler 16, a quaternary air cooler 15 and a fluidized bed cooler 21 to obtain α -alumina, and cooling air in the fluidized bed cooler 21, the primary air cooler 18, the secondary air cooler 17, the tertiary air cooler 16 and the quaternary air cooler 15 enters the heating furnace 12 again for combustion, so that heat is fully utilized.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical substance of the present invention still belong to the protection scope of the technical solution of the present invention.

Claims (8)

1. The utility model provides a roasting system, includes consecutive preheating device, roasting equipment and cooling device, its characterized in that: the roasting device comprises a fluidized bed roasting furnace (14), a preheating device is communicated with a feeding pipe (35) of the fluidized bed roasting furnace (14), a cooling device is communicated with a discharging pipe (43) of the fluidized bed roasting furnace (14), a retention groove (44) is arranged in the fluidized bed roasting furnace (14), the retention groove (44) is arranged between the feeding pipe (35) and the discharging pipe (43) of the fluidized bed roasting furnace (14), a plurality of partition plates (45) are arranged in the retention groove (44) at intervals along the material flowing direction, the retention groove (44) is divided into a plurality of retention bins with upper side openings, and a fluidizing air distribution device at the bottom of the fluidized bed roasting furnace (14) is communicated with the retention bins.

2. The firing system of claim 1, wherein: the bottom of each staying bin is provided with a plurality of air caps (37) at intervals, and each air cap (37) is communicated with the fluidized air distribution device.

3. The firing system of claim 1, wherein: the roasting device also comprises a heating furnace (12), an input port of the heating furnace (12) is communicated with the preheating device, and an output port of the heating furnace (12) is communicated with the feeding pipe (35).

4. The firing system of claim 1, wherein: the preheating device comprises a first-stage preheater (9) and a second-stage preheater (10), a discharge hole of the first-stage preheater (9) is communicated with a feed inlet of the second-stage preheater (10), a discharge hole of the second-stage preheater (10) is communicated with a feed pipe (35) of the fluidized bed roasting furnace (14), an air inlet of the second-stage preheater (10) is communicated with an air outlet cylinder (33) of the fluidized bed roasting furnace (14), and an air outlet of the second-stage preheater (10) is communicated with an air inlet of the first-stage preheater (9).

5. The firing system of claim 1, wherein: the cooling device comprises an air cooling device and a water cooling device which are arranged in series, a discharge pipe (43) of the fluidized bed roasting furnace (14) is communicated with the air cooling device, and the water cooling device is connected with a material output pipe (30).

6. The firing system of claim 5, wherein: the air cooling device comprises air coolers, wherein the air coolers are connected in series to form a plurality of stages, and the air coolers are connected with a cooler fan.

7. The firing system of claim 5, wherein: the water cooling device is a fluidized bed cooler (21), a heat exchange coil is arranged in the fluidized bed cooler (21), and a water inlet of the heat exchange coil is connected with a circulating water pump (22).

8. The firing system as claimed in claim 1 or 5, wherein: two discharge pipes (43) of the fluidized bed roasting furnace (14) are arranged at intervals in the height direction.

Images