Method for synchronously roasting coal gangue lightweight aggregate by using heat of tunnel kiln and energy-saving equipment

Abstract

The present invention discloses a method for manufacturing coal gangue lightweight aggregate and a roasting system. Inside the cross-section of the roasting section of a coal gangue brick tunnel kiln, an internal spiral cylinder type continuous roasting device is provided. The continuous roasting device includes a cylinder body with a rotary internal spiral structure. The cylinder body includes a roasting section and a waste heat section inside the sintered brick tunnel kiln in the length direction. The waste heat drying rotary body is installed outside the roasting section of the coal gangue sintered brick tunnel kiln. The cylinder body of the waste heat section of the continuous roasting device and the internal spiral structure penetrate and are placed inside the waste heat drying rotary body. The running directions of the rotary body and the internal spiral structure inside the cylinder body are opposite. By using the heat of self-combusting sintered coal gangue bricks and waste heat, the coal gangue is dried at 300 - 500 °C, preheated at 400 - 900 °C, and roasted and homogenized at 900 - 950 °C to obtain high-quality lightweight aggregate for lightweight concrete and ready-mixed dry mortar. It solves the problems in the prior art such as the uneven temperature during the self-combustion of spontaneous combustion gangue, the unburned carbon, and the presence of unburned and unhomogenized coal gangue mixed in it. The heat and waste heat of the roasting coal gangue brick tunnel kiln are fully and effectively utilized to synchronously roast the coal gangue lightweight aggregate. The self-combusting coal gangue (red gangue) is roasted at 900 °C - 950 °C by the internal spiral cylinder of the present invention, and the cylinder pressure strength is about twice that of the self-combusting coal gangue (red gangue) without this roasting.

Description

Technical Field

[0001] The present invention belongs to the technical fields of sintered lightweight aggregate and kiln, and relates to a technical method for coal gangue lightweight aggregate and a roasting system, in particular to a method for synchronously roasting coal gangue lightweight aggregate by using the heat of a tunnel kiln and an energy-saving device; it is particularly suitable for synchronously roasting coal gangue lightweight aggregate by using the heat and waste heat of a kiln. Background Art

[0002] Buildings are developing towards prefabrication, and the internal and external wall concrete hanging panels of prefabricated buildings are developing towards lightweight. This requires that the aggregates used must be lightweight and green. Due to the poor performance of slag, the limitation of volcanic slag resources, and the limitation of ceramsite cost, slag, volcanic slag, and ceramsite are rarely selected as lightweight aggregates for concrete and premixed dry mortar in current projects; while coal gangue, especially spontaneous combustion coal gangue, has a wide range of resources, and there are also many tunnel kiln production lines for coal gangue sintered bricks. Using spontaneous combustion coal gangue as the aggregate of concrete and the lightweight aggregate of premixed dry mortar belongs to comprehensive utilization of resources and has broad development prospects.

[0003] When using spontaneous combustion coal gangue as the lightweight aggregate of concrete and premixed dry mortar, it is currently obtained from spontaneous combustion gangue. Spontaneous combustion coal gangue is also called red gangue, and unburned coal gangue is also called black gangue.

[0004] The existing spontaneous combustion coal gangue (red gangue) has a low spontaneous combustion temperature; under natural conditions, during the spontaneous combustion process of spontaneous combustion gangue (red gangue), the temperature is difficult to be uniform, and the carbon is not completely burned, so it will inevitably cause a part of semi-burned and un-sintered and homogenized materials, especially unburned coal gangue (black gangue) mixed in it.

[0005] When the lightweight aggregate of concrete and the lightweight aggregate of premixed dry mortar are mixed with unburned coal gangue (black gangue), it will cause quality risk problems such as low cylinder compressive strength and easy weathering of concrete and premixed dry mortar.

[0006] The existing standard GB / T17431.1: 800 < bulk density ≤ 900 kg / m 3 , cylinder compressive strength ≥ 3.0 MPa, water absorption rate ≤ 10%. Users demand higher cylinder compressive strength. How to improve the coal gangue sintering method and device to make the spontaneous combustion gangue (red gangue) pass through the sintering temperature uniformly in a specially designed device and eliminate semi-burned and unburned coal gangue (black gangue) is a topic studied by engineering and technical personnel in this field. Summary of the Invention

[0007] The present invention discloses a method for manufacturing coal gangue lightweight aggregate and a roasting system to solve the problems in the prior art that during the spontaneous combustion process of spontaneous combustion gangue (red gangue), the temperature is difficult to be uniform, the carbon is not completely burned, and unburned coal gangue (black gangue) that has not been sintered and homogenized is mixed in it.

[0008] The manufacturing method of coal gangue lightweight aggregate disclosed by the present invention includes: having an inner spiral cylinder type continuous roasting device, including a roasting section in the sintering brick tunnel kiln and a waste heat section in the drying device; the roasting section of the continuous roasting device is arranged in the roasting cross-section of the sintering brick tunnel kiln; the waste heat section of the continuous roasting device is arranged in the drying device outside the sintering brick tunnel kiln; the heat contained in the internally fired brick blank stack is 450 - 500 cal / g; the temperature in the roasting section of the coal gangue tunnel kiln can reach about 1000 °C; the continuous roasting device continuously rotates and conveys materials.

[0009] First step, utilizing the waste heat at the cold end of the roasted coal gangue lightweight aggregate, the waste heat section of the continuous roasting device dries the wet materials in the 300 - 500 °C section at the waste heat drying device.

[0010] Second step, the preheated dry materials are input into the inlet of the roasting section of the continuous roasting device in the sintering brick tunnel kiln.

[0011] Third step, in the roasting section of the sintering brick tunnel kiln of the continuous roasting device, the dry materials are roasted in the continuous roasting device in the form of high-temperature muffle roasting by the internally fired brick stack on the kiln car in the cross-section of the tunnel kiln for about 1 - 2 h; the dry materials are preheated at 400 - 900 °C and roasted and homogenized at 900 - 950 °C; high-quality lightweight aggregates for lightweight concrete and premixed dry mortar are obtained.

[0012] The manufacturing method of the coal gangue lightweight aggregate of the present invention: in the firing cross-section, an inner spiral cylinder type continuous roasting device is arranged, and the heat and waste heat of the self-burning sintered coal gangue bricks are utilized to preheat and dry the coal gangue at 400 - 900 °C and roast and homogenize the coal gangue at 900 - 950 °C to obtain high-quality lightweight aggregates for lightweight concrete and premixed dry mortar. The discharging standard particle size range of the fired coal gangue lightweight aggregate is: 5 - 16 mm coarse aggregate particles and 0 - 5 mm fine aggregate particles; other particle sizes can be fired according to needs.

[0013] The small solid arrow is the flowing direction of the dried materials, from the cold end to the hot end; the large solid arrow is the flowing direction of the roasted materials, from the hot end to the cold end; the large hollow arrow is the flowing direction of the roasted materials.

[0014] The technological process is as follows: the arrow is the flowing direction of the materials, wet materials are input into the hopper → dried at 300 - 500 °C in the waste heat drying device → lifted and output by the elevator → dry materials are input into the inner spiral conveyor → dry materials enter the roasting hopper → the heat of the tunnel kiln conducts through the cylinder of the inner spiral cylinder type continuous roasting device by muffle heat transfer, so that the dry materials in the cylinder of the continuous roasting device are preheated at 400 °C - 900 °C; roasted and homogenized at 900 °C - 950 °C → cooled → discharged →

[0015] The coal gangue lightweight aggregate roasting system of the present invention includes: the cross-section of the roasting section of the coal gangue sintered brick tunnel kiln, the waste heat drying rotary body, the continuous roasting equipment, the vertical elevator, the heat-resistant internal spiral conveyor, the first hopper, the second hopper, the dry material feeding hopper, and the chain drive device; the continuous roasting equipment includes a cylinder body with a rotating internal spiral structure; the cylinder body and its internal spiral structure include a roasting section and a waste heat section in the length direction inside the sintered brick tunnel kiln; the roasting section of the cylinder body and its internal spiral structure of the continuous roasting equipment are placed through the cross-section of the firing section of the coal gangue sintered brick tunnel kiln; the waste heat drying rotary body is installed outside the firing section of the coal gangue sintered brick tunnel kiln; the waste heat drying rotary body is cylindrical; there is a hollow internal spiral structure on the inner wall of the inner cylinder of the waste heat rotary body, and the waste heat section of the cylinder body and its internal spiral structure of the continuous roasting equipment are placed through the waste heat drying rotary body; the hollow inner hole of the internal spiral structure is in clearance fit with the outer wall of the cylinder body; the cylinder body and the internal spiral structure in the roasting section inside the sintered brick tunnel kiln belong to the hot end side; the cylinder body and the internal spiral structure in the waste heat section inside the drying device belong to the cold end side; the wet material feeding port is located at the cold end of the waste heat drying rotary body, and the vertical elevator is placed between the waste heat drying rotary body and the sintered brick tunnel kiln, at the hot end discharge port of the rotary body; the upper part of the first hopper is the outlet of the vertical elevator, and the lower end of the first hopper is connected to the inlet of the heat-resistant internal spiral conveyor; there is a second hopper at the hot end of the cylinder body of the continuous roasting equipment; there is a dry material feeding hopper above the second hopper; the outlet of the heat-resistant internal spiral cylinder conveyor is located above the dry material feeding hopper; the dried material is lifted by the vertical elevator into the first hopper; and is transported to the inside of the cylinder body of the continuous roasting equipment through the heat-resistant internal spiral cylinder conveyor and the second hopper; a chain drive device is installed at the hot end of the cylinder body of the continuous roasting equipment, and a chain drive device is installed at the wet material feeding end; the speed regulating motor is drivingly connected to the chain drive device; the speed regulating motor drives to provide power for the cylinder body and the waste heat drying rotary body; the running directions of the internal spiral structure in the rotary body and the internal spiral structure in the cylinder body are opposite; when the cylinder body rotates, the material inside the cylinder body flows from the hot end to the cooling end; when the waste heat drying rotary body rotates, the wet material inside the waste heat drying rotary body flows from the cold end to the hot end along the direction of the solid small arrow, and the wet material is dried by the waste heat of the cylinder body.

[0016] The heat-resistant temperature of the heat-resistant internal spiral conveyor of the present invention is greater than or equal to 500 °C, and it can complete the transportation of materials below 500 °C.

[0017] An optimized structure of the present invention further includes a limit support wheel device and a flat support wheel; the limit support wheel device is installed at the cylinder body at the hot end on one side of the second hopper; the flat support wheel device is installed at the cylinder body at the cold end discharge port side; the limit support wheel device limits the expansion of the cylinder body towards the cold end; the limit support wheel device and the flat support wheel device support the cylinder body and bear the load. The limit support wheel device is installed at the wet material feeding end, and the flat support wheel is installed at the hot end; the limit support wheel device limits the waste heat rotary body, and the limit support wheel device and the flat support wheel device support the waste heat rotary body.

[0018] At the wet material feeding end, the lower part of the wet material feeding hopper is a static cylindrical feeding device, which includes a vertical feeding pipe, an outer end face, and an inner end opening; the cold end of the rotary calcination inner spiral cylinder body is in the hole of the outer end face, and is hermetically connected by a small-gap sliding fit; the inner end opening is in the hole of the cold end face of the drying rotary body, and is hermetically connected by a small-gap sliding fit; the vertical feeding pipe is connected to the wet material feeding hopper; the wet material enters the inner spiral of the waste heat drying rotary body through the static cylindrical feeding device from the wet material feeding hopper, so that the wet material can flow smoothly and is well sealed.

[0019] During operation:

[0020] The wet material enters the inner spiral structure of the waste heat drying rotary body from the wet material feeding hopper, and the material flows from the cold end to the hot end; it is dried by the waste heat at the cold end of the continuous calcination equipment cylinder body.

[0021] The dried material is lifted to the first hopper by a vertical elevator, and then conveyed to the dry material feeding hopper by a heat-resistant inner spiral conveyor. Under the action of the inner spiral, it flows into the second hopper at the hot end of the continuous calcination equipment cylinder body and enters the continuous calcination equipment cylinder body; the through cylinder of the continuous calcination equipment rotates, and the inner spiral structure makes the material in the cylinder flow from the hot end to the cooling end; it runs to the discharge port at the cooling end to discharge, and the finished coal gangue lightweight aggregate is obtained.

[0022] The dried material in the continuous calcination equipment cylinder body is preheated at 400 - 900 °C and calcined at 900 - 950 °C, and is calcined in the form of high-temperature indirect firing of the inner combustion brick stack on the kiln car in the cross section of the tunnel kiln for about 1 - 2 hours; the carbonaceous matter in the material particles is burned off, and at the same time, a thermal silicate reaction occurs, sucking out the liquid phase to make the particles dense and increasing the particle strength; under the action of the continuous conveying of the inner spiral and the temperature in the calcination section of the external tunnel kiln, the process of calcining coal gangue lightweight aggregate is completed. The movement direction of the calcined material is as shown by the large hollow arrow.

[0023] The rotary body makes the wet material move towards the hot end, as shown by the solid arrow; when the high-temperature material in the continuous calcination equipment cylinder body runs to the hot end of the waste heat utilization rotary body, the waste heat temperature of the material in the cylinder body is about 600 °C; the waste heat radiated from the cooling end of the continuous calcination equipment cylinder body is used to dry the wet material in the rotary body, and the material is dried to 300 °C - 500 °C, achieving the purpose of further energy saving.

[0024] The continuous calcination equipment includes a cylinder body with a fully enclosed structure design, and basically achieves dust-free material transportation.

[0025] The positive effects of the present invention are as follows: The heat and waste heat of the tunnel kiln for calcining coal gangue bricks are fully and effectively utilized, and coal gangue lightweight aggregate is calcined synchronously; the self-combustible coal gangue (red gangue) is calcined at 900 - 950 °C in the inner spiral cylinder of the present invention, and the cylinder pressure strength is about twice that of the self-combustible coal gangue (red gangue) without this calcination. Description of the Drawings

[0026] Figure 1 Structural schematic diagram of the present invention;

[0027] In the figure: 1 Cooling end discharge port, 2 Flat supporting wheel, 3 Wet material feeding end, 3.1 Outer end face, 3.2 Static cylindrical feeding device, 3.3 Feeding pipe, 3.4 Wet material feeding hopper, 3.5 Inner end opening, 4 Waste heat drying rotary body, 4.1 Inner spiral structure, 5 Chain drive device, 6 Flat supporting wheel, 7 Hot end of waste heat drying rotary body, 8 Vertical elevator, 9 Heat-resistant inner spiral conveyor, 10 Cylinder body, 11 Cross-section of tunnel kiln, 12 Inner combustion brick blank stack, 13 Kiln car, 14 Chain drive device, 15 Second hopper, 15.1 Dry material feeding hopper, 16 Cold end, 17 Inner spiral structure, 18 Hot end, 19 Limit supporting wheel device, 20 Material to be dried, 21 First hopper, 22 Limit supporting wheel device, 23 Light aggregate finished product hopper; In the figure, small solid arrows indicate the flow direction of dried materials, from the cold end to the hot end; large solid arrows indicate the flow direction of roasted materials, from the hot end to the cold end; large hollow arrows indicate the flow direction of materials after roasting. Embodiment

[0028] The following describes several embodiments of the present invention in detail with reference to the accompanying drawings. The present invention is further described by the following examples.

[0029] There are a large number of national coal gangue sintered brick tunnel kiln production lines, which can be transformed to synchronously roast coal gangue light aggregate.

[0030] In the cross-section of the roasting section of the existing large-section coal gangue brick tunnel kiln of the present invention, an inner spiral cylinder type continuous roasting device is arranged. The heat of the coal gangue tunnel kiln mainly comes from the inner combustion brick blank stack 12, and the inner combustion brick blank stack 12 is stacked on the kiln car 13 in the cross-section of the tunnel kiln. The heat contained in the inner combustion brick blank stack 12 is 450 - 500 cal / g; in the roasting zone of the coal gangue tunnel kiln, that is, the roasting section temperature can reach about 1000 °C, which can meet the temperature required for continuously roasting coal gangue light aggregate by the continuous roasting device. Utilizing the heat and waste heat of self-burning coal gangue bricks, coal gangue is dried at 300 °C - 500 °C, preheated at 400 °C - 900 °C, and roasted and homogenized at 900 °C - 950 °C to obtain high-quality light aggregate for lightweight concrete and premixed dry mortar.

[0031] The first embodiment of the present invention is as follows Figure 1As shown in the figure, the gangue lightweight aggregate roasting system includes: a flat supporting wheel 2, a waste heat drying rotary body 4, a chain drive device 5, a flat supporting wheel 6, a vertical elevator 8, a heat-resistant internal screw conveyor 9, a cross-section of the roasting section of the gangue sintered brick tunnel kiln 11, a chain drive device 14, a second hopper 15, a dry material feeding hopper 15.1, a limiting supporting wheel device 19, a first hopper 21, a limiting supporting wheel device 22, a lightweight aggregate finished product hopper 23, and a continuous roasting device; the continuous roasting device includes a cylinder body 10, and the cylinder body 10 has a rotary internal screw structure 17; the cylinder body 10 and its internal screw structure 17 include a roasting section and a waste heat section in the length direction inside the sintered brick tunnel kiln; the roasting section of the cylinder body 10 and the internal screw structure 17 of the continuous roasting device are penetrated and placed inside the cross-section 11 of the roasting section of the gangue sintered brick tunnel kiln; the waste heat drying rotary body 4 is installed outside the firing section of the gangue sintered brick tunnel kiln; the waste heat drying rotary body 4 is cylindrical; there is a hollow internal screw structure 4.1 on the inner cylinder wall of the waste heat rotary body 4, and the roasting section of the cylinder body 10 and the internal screw structure 17 of the continuous roasting device are penetrated and placed inside the waste heat drying rotary body 4; the hollow inner hole of the internal screw structure 4.1 is in clearance fit with the outer wall of the cylinder body 10.

[0032] The cylinder body 10 and the internal screw structure 17 in the roasting section inside the sintered brick tunnel kiln belong to the hot end 18 side; the cylinder body 10 and the internal screw structure 17 in the waste heat section inside the drying device belong to the cold end 16 side.

[0033] The limiting supporting wheel device 19 is arranged and installed at the cylinder body 10 on one side of the second hopper 15 and at the hot end 18; the flat supporting wheel device 2 is arranged and installed at the cylinder body 10 at the cold end 16 discharge port 1 side; the limiting supporting wheel device 19 enables the cylinder 10 to only expand towards the cold end 16; the limiting supporting wheel device 19 and the flat supporting wheel device 2 support the cylinder body 10 and bear the load.

[0034] A limiting supporting wheel device 22 is provided at the wet material feeding end 3 to limit the waste heat rotary body 4, and a flat supporting wheel 6 is provided at the hot end. The limiting supporting wheel device 22 and the flat supporting wheel device 6 support the waste heat rotary body 4.

[0035] The wet material feeding port 3 is located at the cold end of the waste heat drying rotary body 4. The lower part of the wet material feeding hopper 3.4 is a static cylindrical feeding device 3.2. The static cylindrical feeding device 3.2 includes a vertical feeding pipe 3.3, an outer end face 3.1, and an inner end opening 3.5; the cold end of the rotary roasting internal screw cylinder body 10 is in a small clearance sliding fit and sealing connection in the hole of the outer end face 3.1, and the inner end opening 3.5 is in a small clearance sliding fit and sealing connection in the hole of the cold end face of the drying rotary body 4. The vertical feeding pipe 3.3 is connected to the wet material feeding hopper 3.4; the wet material enters the internal screw structure 4.1 of the waste heat drying rotary body 4 through the static cylindrical feeding device 3.2 from the wet material feeding hopper 3.4; enabling the wet material to flow smoothly in and having good sealing.

[0036] The vertical elevator 8 is placed between the waste heat drying rotary body 4 and the sintered brick tunnel kiln, at the hot end discharge of the rotary body 4; the upper part of the first hopper 21 is the outlet of the vertical elevator 8, and the lower end of the first hopper 21 is connected to the inlet of the heat-resistant internal screw conveyor 9; at the hot end 18 of the cylinder 10 of the continuous roasting equipment, there is a second hopper 15; above the second hopper 15, there is a dry material hopper 15.1; the outlet of the heat-resistant internal screw conveyor 9 is located above the dry material hopper 15.1; the material 20 to be dried is lifted by the vertical elevator 8 into the first hopper 21; and is conveyed into the cylinder 10 of the continuous roasting equipment through the heat-resistant internal screw conveyor 9 and the second hopper 15. The heat-resistant temperature of the heat-resistant internal screw conveyor 9 is greater than or equal to 500 °C, and it can complete the conveying of materials below 500 °C.

[0037] At the hot end 18 of the cylinder 10 of the continuous roasting equipment, there is also a chain drive device 14, and the speed-regulating motor is drivingly connected to the chain drive device 14; the speed-regulating motor drives to provide driving power for the cylinder 10; when the cylinder 10 rotates, the materials in the cylinder flow from the hot end 18 to the cooling end 16. The finished lightweight aggregate enters the lightweight aggregate finished product hopper 23.

[0038] At the wet material feeding end, there is also a chain drive device 5, and the speed-regulating motor is drivingly connected to the chain drive device 5 to provide power for the waste heat drying rotary body 4; the inner spiral structure 4.1 of the rotary body 4 and the inner spiral structure 17 in the cylinder 10 operate in opposite directions; when the waste heat drying rotary body 4 rotates, the wet materials in the waste heat drying rotary body 4 flow from the cold end 16 to the hot end 18 along the direction of the solid small arrow, and the wet materials are dried by the waste heat of the cylinder 10.

[0039] The manufacturing method of coal gangue lightweight aggregate in this embodiment: in the roasting cross-section, an internal spiral cylinder type continuous roasting equipment is set; the continuous roasting equipment 10 continuously rotates and conveys materials; the first step, the continuous roasting equipment utilizes the waste heat at the cold end of the roasted coal gangue lightweight aggregate to dry the wet materials in the 300 - 500 °C section at the waste heat drying device; the second step, the preheated dry materials are input into the inlet of the roasting section in the sintered brick tunnel kiln of the continuous roasting equipment; the third step, in the roasting section of the sintered brick tunnel kiln of the continuous roasting equipment, the dry materials are roasted in the continuous roasting equipment in the form of high-temperature indirect firing by the internal combustion brick stack 12 on the kiln car 13 in the cross-section of the tunnel kiln for about 1 - 2 h; the dry materials are preheated at 400 - 900 °C and roasted and homogenized at 900 - 950 °C; high-quality lightweight aggregates for lightweight concrete and ready-mixed dry mortar are obtained; the standard particle size range of the discharged coal gangue lightweight aggregates after firing is: 5 - 16 mm coarse aggregate particles and 0 - 5 mm fine aggregate particles; other particle sizes can be fired according to needs.

[0040] The technological process is as follows: Wet materials are input into the hopper → dried at 300 - 500°C in the waste heat drying device → lifted by the elevator and output as dry materials → the dry materials are input into the inner screw conveyor → the dry materials enter the roasting hopper → the heat of the tunnel kiln is conducted through the rotary roasting inner screw cylinder 10 by radiation heat, so that the dry materials in the rotary roasting inner screw cylinder are preheated at 400°C - 900°C; roasted and homogenized at 900°C - 950°C → cooled → discharged.

[0041] During operation:

[0042] The wet materials enter the waste heat drying rotary body 4 from the wet material feeding hopper 3.4; inside the drying inner screw 4.1 of the waste heat drying rotary body 4, the materials flow from the cooling end 16 to the hot end 18; and are dried by the waste heat at the cold end of the rotary roasting inner screw cylinder 10.

[0043] The dried materials 20 are lifted to the first hopper 21 by the vertical elevator 8, and then conveyed to the dry material feeding hopper 15.1 by the heat-resistant inner screw conveyor 9 under the action of the inner screw, and flow into the second hopper 15 at the hot end 18 of the rotary roasting inner screw cylinder 10 and enter the rotary roasting inner screw cylinder 10; the rotary inner screw structure 17 of the continuous roasting equipment 10 makes the materials in the cylinder flow from the hot end 18 to the cooling end 16; and are discharged from the discharge port 1 at the cooling end as the finished coal gangue lightweight aggregate.

[0044] The dried materials 20 in the continuous roasting equipment cylinder 10 are preheated at 400 - 900°C and roasted at 900 - 950°C, and are roasted in the form of high-temperature radiation separation by the internal combustion brick stack 12 on the kiln car 13 in the cross-section of the tunnel kiln for about 1 - 2 hours; the carbonaceous matter in the material particles is burned off, and at the same time, a thermal silicate reaction occurs, sucking out the liquid phase to make the particles dense and increasing the particle strength; the process of roasting coal gangue lightweight aggregate is completed under the continuous transportation of the inner screw 17 and the temperature action of the firing section of the external tunnel kiln.

[0045] The rotary body 4 makes the wet materials move towards the hot end 7, as shown by the solid arrow; when the high-temperature materials in the continuous roasting equipment cylinder 10 run to the hot end 7 of the waste heat utilization rotary body 4, the waste heat temperature of the materials in the cylinder 10 is about 600°C; the waste heat radiated from the cooling end of the continuous roasting equipment cylinder 10 is used to dry the wet materials in the rotary body 4, and the materials are dried to 300°C - 500°C; achieving the purpose of further energy saving.

[0046] As Figure 1 shown: The small solid arrow is the flow direction of the dried materials, from the cooling end 16 to the hot end 18; the large solid arrow is the flow direction of the roasted materials, from the hot end 18 to the cooling end 16; the large hollow arrow is the flow direction of the roasted materials.

[0047] The continuous roasting equipment includes a cylinder with a fully enclosed structure design, basically achieving dust-free material transportation.

[0048] The measured main technical performance indicators of the self - combusted gangue (red gangue) lightweight aggregate without simulated sintering in Embodiment 1 of the present invention are: bulk density 1060 kg / m3, cylinder compressive strength 3.1 MPa, water absorption rate 9.8%.

[0049] For the gangue lightweight aggregate after simulated sintering in Embodiment 1 of the present invention, the measured main technical performance indicators are: bulk density 860 kg / m3, cylinder compressive strength 6.4 MPa, water absorption rate 8.6%.

[0050] Judging from the cylinder compressive strength index, the gangue lightweight aggregate after simulated sintering according to the present invention is far superior to the index of the self - combusted gangue (red gangue) without sintering according to the present invention.

[0051] In the second embodiment of the present invention, it is different from the full - length inner spiral structure of the waste heat drying rotary body 4, heat - resistant inner spiral conveyor 9, and continuous roasting equipment cylinder body 10 in the first embodiment; for the waste heat drying rotary body 4, heat - resistant inner spiral conveyor 9, and continuous roasting equipment cylinder body 10 in the second embodiment, only several rings of inner spiral structures are fixedly arranged at the feeding end respectively, and the purpose of conveying materials can be achieved.

[0052] The above embodiments do not limit the present invention in any way. Without departing from the technical solution of the present invention, any modification or change that is easily achieved by those of ordinary skill in the art to the present invention will fall within the scope of the claims of the present invention.

Claims

1. A coal gangue lightweight aggregate roasting system, comprising: Cross-section of the roasting section of the coal gangue sintered brick tunnel kiln, waste heat drying rotary body, continuous roasting equipment, vertical elevator, heat-resistant internal screw conveyor, first hopper, second hopper, dry material feed hopper, chain drive device; The continuous roasting equipment includes a cylinder body with a rotating internal screw structure; The cylinder body and its internal screw structure include a roasting section and a waste heat section inside the coal gangue sintered brick tunnel kiln in the length direction; The cylinder body of the continuous roasting equipment and the roasting section of the internal screw structure are placed through the cross-section of the roasting section of the coal gangue sintered brick tunnel kiln; The waste heat drying rotary body is installed outside the roasting section of the coal gangue sintered brick tunnel kiln; The waste heat drying rotary body is cylindrical; There is a hollow internal screw structure on the inner wall of the inner cylinder of the waste heat rotary body, and the cylinder body and the internal screw structure of the waste heat section of the continuous roasting equipment are placed through the waste heat drying rotary body; The hollow inner hole of the internal screw structure is in clearance fit with the outer wall of the cylinder body; The cylinder body in the roasting section inside the coal gangue sintered brick tunnel kiln is located on the hot end side; The cylinder body in the waste heat section inside the drying device is located on the cold end side; The wet material feed port is located at the cold end of the waste heat drying rotary body, and the vertical elevator is placed between the waste heat drying rotary body and the coal gangue sintered brick tunnel kiln, at the hot end discharge of the rotary body; The upper part of the first hopper is the outlet of the vertical elevator, and the lower end of the first hopper is connected to the inlet of the heat-resistant internal screw conveyor; A second hopper is placed at the hot end of the cylinder body of the continuous roasting equipment; A dry material feed hopper is placed above the second hopper; The outlet of the heat-resistant internal screw conveyor is located above the dry material feed hopper; The material to be dried is lifted to the first hopper by the vertical elevator; It is transported to the inside of the cylinder body of the continuous roasting equipment through the heat-resistant internal screw conveyor and the second hopper; A chain drive device is installed at the hot end of the cylinder body of the continuous roasting equipment, and a chain drive device is installed at the wet material feed end; The speed regulating motor is drivingly connected to the chain drive device; The speed regulating motor drives to provide power for the cylinder body and the waste heat drying rotary body; The running directions of the internal screw structure in the rotary body and the internal screw structure in the cylinder body are opposite; When the cylinder body rotates, the material inside the cylinder body flows from the hot end to the cooling end; When the waste heat drying rotary body rotates, the wet material inside the waste heat drying rotary body flows from the cold end to the hot end; It also includes a limit supporting wheel device and a flat supporting wheel; A limit supporting wheel device is installed at the cylinder body on one side of the second hopper and at the hot end; A flat supporting wheel device is installed at the cylinder body on the cold end discharge port side; The limit supporting wheel device limits the expansion of the cylinder body towards the cold end; The limit supporting wheel device and the flat supporting wheel device support the cylinder body; A limit supporting wheel device is installed at the wet material feed end, and a flat supporting wheel is installed at the hot end; The limit supporting wheel device limits the waste heat rotary body, and the limit supporting wheel device and the flat supporting wheel device support the waste heat rotary body; At the wet material feed end, the lower part of the wet material feed hopper is a static cylindrical feeding device, and the static cylindrical feeding device includes a vertical feeding pipe, an outer end face, and an inner end opening; The cold end of the rotary roasting internal screw cylinder body is located in the hole of the outer end face, and is connected in a closed manner with a small clearance sliding fit; The inner end opening is located in the hole of the cold end face of the drying rotary body, and is connected in a closed manner with a small clearance sliding fit; The vertical feeding pipe is connected to the wet material feed hopper.

2. The coal gangue lightweight aggregate roasting system according to claim 1, wherein: The heat-resistant temperature of the heat-resistant internal screw conveyor is greater than or equal to 500 °C.

3. A manufacturing method for manufacturing coal gangue lightweight aggregate using the coal gangue lightweight aggregate roasting system as described in claim 1, characterized in that: There is an internal spiral cylinder type continuous roasting device, including a roasting section in the sintered brick tunnel kiln and a waste heat section in the drying device; the roasting section of the continuous roasting device is arranged in the roasting cross-section of the sintered brick tunnel kiln; the waste heat section of the continuous roasting device is arranged in the drying device outside the sintered brick tunnel kiln; the heat contained in the internally fired brick blank stack is 450 - 500 cal / g; the temperature in the roasting section of the coal gangue tunnel kiln can reach about 1000 °C; the continuous roasting device continuously rotates to convey materials. First step, utilize the waste heat at the cold end of the roasted coal gangue lightweight aggregate. The waste heat section of the continuous roasting device dries the wet materials in the 300 - 500 °C section at the waste heat drying device. Second step, input the preheated dry materials into the inlet of the roasting section of the continuous roasting device in the sintered brick tunnel kiln. Third step, in the roasting section of the sintered brick tunnel kiln of the continuous roasting device, the dry materials are roasted in the continuous roasting device in the form of high-temperature muffle roasting by the internally fired brick stack on the kiln car in the cross-section of the tunnel kiln for 1 - 2 h; the dry materials are preheated at 400 °C - 900 °C and roasted and homogenized at 900 °C - 950 °C.

4. A method for manufacturing coal gangue lightweight aggregate according to claim 3, characterized in that: The standard particle size range of the discharged coal gangue lightweight aggregate after firing is: 5 - 16 mm granular coarse aggregate and 0 - 5 mm granular fine aggregate.

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