Lime production system adopting rotary kiln to calcine marble fine powder

Abstract

The utility model discloses a lime production system adopting a rotary kiln to calcine marble fine powder, which comprises the rotary kiln, a cooling machine and a raw material temporary storage bin, and an air outlet of a kiln tail smoke chamber of the rotary kiln is communicated with an air inlet of a secondary preheater. A gas outlet and a feeding port of the second-stage preheater are communicated with a gas inlet and a discharging port of the first-stage preheater respectively, a discharging port of the second-stage preheater is communicated with the feeding end of the rotary kiln, and a feeding port of the first-stage preheater is communicated with a discharging port of the raw material temporary storage bin. A gas outlet of the first-stage preheater is communicated with the waste gas treatment mechanism, and a feeding hole of the raw material temporary storage bin is communicated with the powder selecting mechanism; the discharging end of the rotary kiln is connected with the feeding end of the cooling machine, and a kiln head cover cooling fan is arranged at the discharging end of the rotary kiln. The utility model adopts the rotary kiln to calcine marble fine powder to produce lime, not only solves the problems that a large amount of stone powder is accumulated to occupy the space and pollute the environment, but also can turn waste into wealth.

Description

Technical Field

[0001] The utility model relates to a lime production system, in particular to a lime production system which adopts a rotary kiln to calcine marble fine powder. Background Art

[0002] A large amount of waste will be generated during the processing of marble, mainly including stone scraps and stone powder. At present, stone scraps have been fully reused, but there is no better way to deal with stone powder. For example, in the process of producing lime and magnesium, the existing equipment (vertical kiln, rotary kiln) can only calcine large particles of materials larger than 10mm, while the marble fine powder smaller than 10mm cannot be effectively utilized and can only be piled up. If the stone powder is only piled up, it will cause waste of land and resources, and pollute water sources, which is very harmful. Therefore, how to properly handle and utilize these stone powder wastes and turn waste into treasure has become a problem of great concern to stone companies.

[0003] Lime is an air-hardening inorganic cementitious material with calcium oxide as the main component. Lime is made from limestone, dolomite, chalk, shells and other products with high calcium carbonate content, calcined at 900-1100℃. Lime is the earliest cementitious material used by humans. Lime is widely used in civil engineering and can also be used in medicine in my country.

[0004] Patent CN107879715A provides a method for preparing artificial stone by low-temperature sintering of modified marble powder. In addition to marble powder, surface modifier, sodium carbonate, barium sulfate, tea residue, and cement need to be added additionally, ball-milled, and then mixed and stirred to obtain modified marble powder, and then fly ash, diatomaceous earth, cross-linked rectorite, clay, zinc oxide, and tourmaline powder are added, mixed and stirred, and the mixture is mixed with nano-alumina, titanium dioxide, and sodium carboxymethyl cellulose. The mixture is pressure-formed and dried, and then low-temperature sintered at 300-400°C for 1-2h to obtain artificial stone. This method has a complex formula and a cumbersome process flow. Utility Model Content

[0005] The technical problem to be solved by the utility model is to overcome the shortcomings of the prior art and provide a lime production system which adopts a rotary kiln to calcine marble fine powder, which has a reasonable design, simplifies the production process, makes full use of fine powder and reduces the accumulation process.

[0006] The technical solution of the utility model is:

[0007] A lime production system for calcining marble fine powder using a rotary kiln comprises a rotary kiln, a cooler and a raw material buffer bin, wherein a kiln tail smoke chamber is provided at the feed end of the rotary kiln, an air outlet of the kiln tail smoke chamber is communicated with an air inlet of a secondary preheater, an air outlet and a feed port of the secondary preheater are communicated with an air inlet and a discharge port of a primary preheater respectively, an discharge port of the secondary preheater is communicated with the feed end of the rotary kiln, an feed port of the primary preheater is communicated with an discharge port of the raw material buffer bin, an air outlet of the primary preheater is communicated with an exhaust gas treatment mechanism, and an feed port of the raw material buffer bin is communicated with a powder selection mechanism; the discharge end of the rotary kiln is connected with the feed end of the cooler, a finished product outlet is provided at the discharge end of the cooler, and a kiln head hood cooling fan is provided at the discharge end of the rotary kiln.

[0008] Furthermore, the rotary kiln and the cooler are rotated by a supporting mechanism and a driving mechanism respectively, and the rotary kiln and the cooler are cooled by circulating water respectively.

[0009] Furthermore: the discharge port of the raw material buffer bin is connected to the feed port of the bucket elevator through a spiral gate valve, a flow stabilizing screw and a metering spiral scale in sequence, and the discharge port of the bucket elevator is connected to the feed port of the primary preheater through a rotary discharger and an electric gate valve in sequence.

[0010] Furthermore: the upper air outlet of the raw material buffer bin is connected to the air inlet of the stand-alone bag dust collector through a butterfly valve, the discharge port of the stand-alone bag dust collector is connected to the raw material buffer bin through a star-shaped unloading valve, and the air outlet of the stand-alone bag dust collector is connected to the atmosphere or to the exhaust gas treatment mechanism.

[0011] Further: the exhaust gas treatment mechanism includes an induced draft fan, a bag filter and a second centrifugal fan, the exhaust gas discharged from the primary preheater enters the bag filter through the induced draft fan and the exhaust pipe for dust removal and filtration, the exhaust gas discharged from the bag filter enters the chimney through the second centrifugal fan for external discharge, and the discharge port of the bag filter is connected to the feed port of the second air conveying chute;

[0012] The powder selection mechanism includes a V-type powder selector, a dynamic powder selector, a first plate chain elevator, a cyclone and a first centrifugal fan. The feed port and air inlet of the V-type powder selector are respectively communicated with the discharge port and the air inlet pipe of the first plate chain elevator, the discharge port and air outlet of the V-type powder selector are respectively communicated with the double-shaft mixer and the air outlet of the dynamic powder selector, the discharge port of the double-shaft mixer is communicated with the feed port of the first plate chain elevator, the air outlet and discharge port of the dynamic powder selector are respectively communicated with the air inlet of the cyclone and the double-shaft mixer, the air outlet and discharge port of the cyclone are respectively communicated with the air inlet of the first centrifugal fan and the feed port of the first air conveying chute, the discharge port of the first air conveying chute is communicated with the feed port of the second plate chain elevator, the discharge port of the second plate chain elevator is communicated with the feed port of the raw material buffer bin, and the discharge port of the second air conveying chute is communicated with the first air conveying chute.

[0013] Furthermore: the air outlet of the first centrifugal fan is divided into two branches, the two branches are connected to the air inlet pipe and the exhaust pipe through electric butterfly valves respectively, the air inlet pipe and the exhaust pipe are connected through a connecting pipe, and another electric butterfly valve is arranged on the connecting pipe.

[0014] Furthermore: the box feeder transfers the marble fine powder to the plough type discharger through the roller scale and the belt conveyor, and after the plough type discharger divides the marble fine powder, the marble fine powder enters the first dividing bin and the second dividing bin respectively;

[0015] The marble powder in the first material bin enters a spreading machine through a belt feeder and a belt conveyor, and the marble powder passing through the spreading machine is spread on a drying field, and then turned by a turning machine so that the marble powder can be dried in the sun, and the dried marble powder enters the first storage bin;

[0016] The marble powder in the second material bin enters another material distributor through another set of belt feeders and belt conveyors. The marble powder passing through the distributor is spread on the drying field, and then pushed and turned by the bucket of a forklift to dry the marble powder. The dried marble powder enters the second material storage bin.

[0017] The marble fine powder in the first storage bin and the second storage bin enters the belt conveyor through belt feeders respectively, and the belt conveyor conveys the marble fine powder to the feed port of the double-shaft mixer through roller scales.

[0018] The beneficial effects of the utility model are:

[0019] 1. The raw material of the utility model is marble fine powder, which is a waste material in the marble processing process. It is calcined in a rotary kiln to produce lime, providing services for the recycling of resources.

[0020] 2. The utility model adopts two-stage cyclone preheating, which can effectively reduce the powder carried away by the kiln tail fan and preheat the material, saving energy while reducing the difficulty of tail gas treatment.

[0021] 3. The utility model adopts natural gas as fuel and adopts a multi-channel natural gas burner, which can quickly adjust the sintering temperature and make timely adjustments according to different products, and the sintering effect is good.

[0022] 4. The utility model not only solves the problem of stone powder accumulation occupying a large amount of space and polluting the environment, but also realizes the transformation of waste into treasure, is easy to promote, and has good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is one of the partial structural diagrams of a lime production system using a rotary kiln to calcine marble fine powder;

[0024] Figure 2 This is the second partial structural diagram of a lime production system that uses a rotary kiln to calcine marble fine powder. DETAILED DESCRIPTION

[0025] Example: See Figure 1 -- Figure 2 In the figure, 1-metering spiral scale, 2-stable flow spiral, 3-bucket elevator, 4-secondary preheater, 5-raw material buffer, 6-single bag dust collector, 7-primary preheater, 8-single-layer heavy hammer lock air valve, 9-expansion joint, 10-kiln tail smoke chamber, 11-rotary kiln, 12-kiln head hood cooling fan, 13-burner, 14-cooler, 15-vertical cooler, 16-box feeder, 17-first sub-bin, 18-plough type unloader, 19-second sub-bin Silo, 20- material placing machine, 21- material turning machine, 22- first storage silo, 23- belt feeder, 24- second storage silo, 25- double-shaft mixer, 26- V-type powder selecting machine, 27- dynamic powder selecting machine, 28- first plate chain elevator, 29- cyclone, 30- first centrifugal fan, 31- bag dust collector, 32- second centrifugal fan, 33- induced draft fan, 34- second plate chain elevator, 35- first air conveying chute, 36- second air conveying chute.

[0026] A lime production system for calcining marble fine powder using a rotary kiln comprises a rotary kiln 11, a cooler 14 and a raw material buffer bin 5, wherein: a kiln tail smoke chamber 10 is provided at the feed end of the rotary kiln 11, the air outlet of the kiln tail smoke chamber 10 is communicated with the air inlet of a secondary preheater 4, the air outlet and feed port of the secondary preheater 4 are respectively communicated with the air inlet and the discharge port of a primary preheater 7, the discharge port of the secondary preheater 4 is communicated with the feed end of the rotary kiln 11, the feed port of the primary preheater 7 is communicated with the discharge port of the raw material buffer bin 5, the air outlet of the primary preheater 7 is communicated with an exhaust gas treatment mechanism, and the feed port of the raw material buffer bin 5 is communicated with a powder selection mechanism; the discharge end of the rotary kiln 11 is connected to the feed end of the cooler 14, the discharge end of the cooler 14 is provided with a finished product outlet, and the discharge end of the rotary kiln 11 is provided with a kiln head hood cooling fan 12.

[0027] According to the needs, a single-layer weight lock air valve 8 and an expansion joint 9 are respectively arranged between the secondary preheater 4 and the rotary kiln 11, between the primary preheater 7 and the secondary preheater 4, and an expansion joint is arranged between the kiln tail smoke chamber 10 and the secondary preheater 4. The primary preheater 7 and the secondary preheater 4 are both cyclone preheaters.

[0028] As required, a vertical cooler 15 may be provided at the discharge end of the cooler 14 to increase the cooling effect, and a finished product outlet is provided at the lower end of the vertical cooler 15 .

[0029] In addition, the rotary kiln 11 is equipped with a multi-channel natural gas burner 13, which can quickly adjust the sintering temperature and make timely adjustments according to different products.

[0030] Preferred solution: The rotary kiln 11 and the cooler 14 are rotated by a supporting mechanism and a driving mechanism respectively, and the rotary kiln 11 and the cooler 14 are cooled by circulating water respectively.

[0031] Optimal solution: The discharge port of the raw material buffer bin 5 is connected to the feed port of the bucket elevator 3 through the spiral gate valve, the flow stabilizing screw 2 and the metering spiral scale 1 in sequence, and the discharge port of the bucket elevator 3 is connected to the feed port of the primary preheater 7 through the rotary discharger and the electric gate valve in sequence.

[0032] Optimal solution: the upper air outlet of the raw material buffer bin 5 is connected to the air inlet of the single-machine bag dust collector 6 through a butterfly valve, the discharge port of the single-machine bag dust collector 6 is connected to the raw material buffer bin 5 through a star-shaped unloading valve, and the air outlet of the single-machine bag dust collector 6 is connected to the atmosphere or to the exhaust gas treatment mechanism.

[0033] Preferred solution: the waste gas treatment mechanism includes an induced draft fan 33, a bag dust collector 31 and a second centrifugal fan 32. The waste gas discharged from the primary preheater 7 enters the bag dust collector 31 through the induced draft fan 33 and the exhaust pipe for dust removal and filtration. The waste gas discharged from the bag dust collector 31 enters the chimney through the second centrifugal fan 32 for external discharge. The discharge port of the bag dust collector 31 is connected to the feed port of the second air conveying chute 36.

[0034] The powder selection mechanism includes a V-type powder selection machine 26, a dynamic powder selection machine 27, a first plate chain elevator 28, a cyclone 29 and a first centrifugal fan 30. The feed port and air inlet of the V-type powder selection machine 26 are respectively connected to the discharge port and air inlet pipe of the first plate chain elevator 28, the discharge port and air outlet of the V-type powder selection machine 26 are respectively connected to the air outlets of the double-shaft mixer 25 and the dynamic powder selection machine 27, the discharge port of the double-shaft mixer 25 is connected to the feed port of the first plate chain elevator 28, the dynamic powder selection machine 27 is connected to the feed port of the first plate chain elevator 28, and the discharge port of the first plate chain elevator 28 is connected to the feed port of the first plate chain elevator 28. The air outlet and the material discharge port are respectively connected to the air inlet of the cyclone 29 and the biaxial mixer 25, the air outlet and the material discharge port of the cyclone 29 are respectively connected to the air inlet of the first centrifugal fan 30 and the material discharge port of the first air conveying chute 35, the material discharge port of the first air conveying chute 35 is connected to the material discharge port of the second plate chain elevator 34, the material discharge port of the second plate chain elevator 34 is connected to the material discharge port of the raw material buffer bin 5, and the material discharge port of the second air conveying chute 36 is connected to the first air conveying chute 35.

[0035] Preferred solution: The air outlet of the first centrifugal fan 30 is divided into two branches, which are connected to the air inlet pipe and the exhaust pipe through electric butterfly valves respectively. The air inlet pipe and the exhaust pipe are connected through a connecting pipe, and another electric butterfly valve is provided on the connecting pipe. According to needs, other electric butterfly valves are respectively installed on the air inlet pipe and the exhaust pipe.

[0036] Optimal solution: the box feeder 16 transfers the marble powder to the plough discharger 18 through the roller scale and the belt conveyor. After the plough discharger 18 divides the marble powder, the marble powder enters the first dividing bin 17 and the second dividing bin 19 respectively.

[0037] The marble powder in the first sub-bin 17 enters the distribution machine 20 through the belt feeder and the belt conveyor. The marble powder passing through the distribution machine 20 is spread on the drying field, and then turned by the turning machine 21 so that the marble powder can be fully dried. After drying, the marble powder enters the first storage bin 22.

[0038] The marble powder in the second material bin 19 enters another material distributor 20 through another set of belt feeders and belt conveyors. The marble powder passing through the material distributor 20 is spread on the drying field, and then pushed and turned by the bucket of the forklift so that the marble powder can be fully dried. After drying, the marble powder enters the second material storage bin 24.

[0039] The marble powder in the first storage bin 22 and the second storage bin 24 enter the belt conveyor through the belt feeder 23 respectively, and the belt conveyor conveys the marble powder to the feed port of the double-shaft mixer 25 through the roller scale.

[0040] During material preparation, the raw materials are transported from the material yard to the box feeder 16 by the bucket of a forklift. After classification, two drying schemes are implemented. The raw materials after the two dryings are all entered into the double-shaft mixer 25 for stirring. The stirred materials are transported to the V-type powder selector 26 by the first plate chain elevator 28 for primary sorting. The marble powder with large particle size enters the double-shaft mixer 25 from the discharge port of the V-type powder selector 26 for a new round of stirring. During the stirring process, they collide with each other, and the particle size becomes smaller, and they are sorted again. The marble powder with small particle size enters the dynamic powder selector 27 from the air outlet of the V-type powder selector 26 for further sorting. The marble powder with large particle size sorted again enters the double-shaft mixer 25 again, and the marble powder with small particle size sorted again enters the cyclone 29. The qualified fine powder sorted by the cyclone 29 enters the first air conveying chute 35, and is then transported to the raw material buffer bin 5 by the second plate chain elevator 34 for standby use.

[0041] The gas discharged from the cyclone 29 enters the exhaust pipe through the first centrifugal fan 30 and then enters the bag filter 31. The marble fine powder separated by the bag filter 31 enters the first air conveying chute 35 through the second air conveying chute 36 and finally enters the raw material buffer bin 5.

[0042] During calcination, the burner 13 is turned on to provide heat to the rotary kiln 11, and the calcination hot gas enters the secondary preheater 4 and the primary preheater 7 in sequence from the kiln tail smoke chamber 10, and the marble fine powder in the raw material buffer bin 5 enters the rotary kiln 11 through the primary preheater 7 and the secondary preheater 4 in sequence for calcination.

[0043] When the marble fine powder passes through the primary preheater 7 and the secondary preheater 4, due to the effect of high-temperature flue gas, part of the marble fine powder is calcined into lime, and finally enters the rotary kiln 11 is a mixture of marble fine powder and lime. The final marble fine powder is calcined in the rotary kiln 11 to form lime. After calcination, it is discharged from the discharge port after passing through the cooler 14 and sent to the finished product warehouse.

[0044] The above is only a preferred embodiment of the utility model, and does not limit the utility model in any form. Any simple modification made according to the technical essence of the utility model still falls within the scope of the technical solution of the utility model.

Claims

1. A lime production system using a rotary kiln to calcine marble fine powder, comprising a rotary kiln, a cooler and a raw material buffer bin, characterized in that: The feed end of the rotary kiln is provided with a kiln tail smoke chamber, the air outlet of the kiln tail smoke chamber is communicated with the air inlet of the secondary preheater, the air outlet and feed port of the secondary preheater are respectively communicated with the air inlet and discharge port of the primary preheater, the discharge port of the secondary preheater is communicated with the feed end of the rotary kiln, the feed port of the primary preheater is communicated with the discharge port of the raw material buffer bin, the air outlet of the primary preheater is communicated with an exhaust gas treatment mechanism, and the feed port of the raw material buffer bin is communicated with a powder selection mechanism; the discharge end of the rotary kiln is connected to the feed end of the cooler, the discharge end of the cooler is provided with a finished product outlet, and the discharge end of the rotary kiln is provided with a kiln head hood cooling fan.

2. The lime production system using a rotary kiln to calcine marble fine powder according to claim 1 is characterized in that: The rotary kiln and the cooler are rotated by a supporting mechanism and a driving mechanism respectively, and are cooled by circulating water respectively.

3. The lime production system using a rotary kiln to calcine marble fine powder according to claim 1 is characterized in that: The discharge port of the raw material buffer bin is connected to the feed port of the bucket elevator through a spiral gate valve, a flow stabilizing screw and a metering spiral scale in sequence, and the discharge port of the bucket elevator is connected to the feed port of the primary preheater through a rotary discharger and an electric gate valve in sequence.

4. The lime production system using a rotary kiln to calcine marble fine powder according to claim 1 is characterized by: The upper air outlet of the raw material buffer bin is connected to the air inlet of the stand-alone bag dust collector through a butterfly valve, the discharge port of the stand-alone bag dust collector is connected to the raw material buffer bin through a star-shaped unloading valve, and the air outlet of the stand-alone bag dust collector is connected to the atmosphere or to the exhaust gas treatment mechanism.

5. The lime production system using a rotary kiln to calcine marble fine powder according to claim 1 is characterized by: The exhaust gas treatment mechanism includes an induced draft fan, a bag filter and a second centrifugal fan. The exhaust gas discharged from the primary preheater enters the bag filter through the induced draft fan and the exhaust pipe for dust removal and filtration. The exhaust gas discharged from the bag filter enters the chimney through the second centrifugal fan for external discharge. The discharge port of the bag filter is connected to the feed port of the second air conveying chute. The powder selection mechanism includes a V-type powder selector, a dynamic powder selector, a first plate chain elevator, a cyclone and a first centrifugal fan. The feed port and air inlet of the V-type powder selector are respectively communicated with the discharge port and the air inlet pipe of the first plate chain elevator, the discharge port and air outlet of the V-type powder selector are respectively communicated with the double-shaft mixer and the air outlet of the dynamic powder selector, the discharge port of the double-shaft mixer is communicated with the feed port of the first plate chain elevator, the air outlet and discharge port of the dynamic powder selector are respectively communicated with the air inlet of the cyclone and the double-shaft mixer, the air outlet and discharge port of the cyclone are respectively communicated with the air inlet of the first centrifugal fan and the feed port of the first air conveying chute, the discharge port of the first air conveying chute is communicated with the feed port of the second plate chain elevator, the discharge port of the second plate chain elevator is communicated with the feed port of the raw material buffer bin, and the discharge port of the second air conveying chute is communicated with the first air conveying chute.

6. The lime production system using a rotary kiln to calcine marble fine powder according to claim 5 is characterized by: The air outlet of the first centrifugal fan is divided into two branches, which are respectively connected to the air inlet pipe and the exhaust pipe through electric butterfly valves. The air inlet pipe and the exhaust pipe are connected through a connecting pipe, and another electric butterfly valve is arranged on the connecting pipe.

7. The lime production system using a rotary kiln to calcine marble fine powder according to claim 5 is characterized by: The box feeder transfers the marble fine powder to the plough type discharger through the roller scale and the belt conveyor. After the plough type discharger divides the marble fine powder, the marble fine powder enters the first dividing bin and the second dividing bin respectively. The marble powder in the first material bin enters a spreading machine through a belt feeder and a belt conveyor, and the marble powder passing through the spreading machine is spread on a drying field, and then turned by a turning machine so that the marble powder can be dried in the sun, and the dried marble powder enters the first storage bin; The marble powder in the second material bin enters another material distributor through another set of belt feeders and belt conveyors. The marble powder passing through the distributor is spread on the drying field, and then pushed and turned by the bucket of a forklift to dry the marble powder. The dried marble powder enters the second material storage bin. The marble fine powder in the first storage bin and the second storage bin enters the belt conveyor through belt feeders respectively, and the belt conveyor conveys the marble fine powder to the feed port of the double-shaft mixer through roller scales.

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