Continuous high-purity quartz sand roasting purification production line and process method

Abstract

The application relates to the technical field of quartz sand purification, and discloses a continuous high-purity quartz sand roasting and purifying production line and a process method, the production line comprises a pretreatment area and a clean purifying and packaging area which are sequentially connected, the pretreatment area comprises a coarse crushing and cleaning unit, a high-temperature roasting unit, a pure water cooling and conveying unit, a crushing and screening unit and a first magnetic separation unit, the clean purifying and packaging area comprises a wet purifying unit, a drying unit, a second magnetic separation unit and a packaging unit. The method comprises the following steps: S1, hot-state quartzite is not landed in pure water and is rapidly cooled; S2, crushing, screening and pre-magnetic separation are carried out; S3, impurities are removed through flotation and double-cone dynamic pickling; S4, dehydration, drying and terminal magnetic separation are carried out; and S5, closed packaging is carried out. Through hot-state non-landing rapid cooling, clean area closed conveying and double-cone dynamic pickling and gas pressure liquid discharge, the application can reduce transfer pollution and improve the stability of the purifying process.

Description

Technical Field

[0001] This invention relates to the field of quartz sand purification technology, and in particular to a continuous high-purity quartz sand roasting and purification production line and process. Background Technology

[0002] High-purity quartz sand is a commonly used basic material in photovoltaic, semiconductor, and quartz product fields. Its impurity content and product stability will affect the subsequent application effect.

[0003] Existing quartz sand purification processes typically include steps such as washing, crushing, roasting, cooling, pulverizing, screening, magnetic separation, flotation, acid washing, dewatering, drying, and packaging. These steps are mostly completed by different equipment, and the processes are usually connected by ordinary conveying, temporary storage, or transfer methods. If the roasted quartz is naturally cooled, piled up on the ground, or externally transferred before entering the subsequent processes, it is easy for it to come into contact with dust, metal impurities, or other external pollutants in the ordinary production environment during the transfer process, thereby affecting the stability of the subsequent purification process.

[0004] In the wet purification process, existing processes mostly use pickling tanks or ordinary reaction kettles to pickle quartz sand. In this type of treatment, there is still room for improvement in the uniformity of contact between quartz sand and acid, the solid-liquid separation method after pickling, and the connection method between pickling equipment and subsequent dewatering equipment. If the pickled material needs to be transferred multiple times, it may also increase the complexity of operation and the risk of secondary pollution.

[0005] In addition, after deep purification processes such as flotation and acid washing, quartz sand is more sensitive to dust, metal particles and equipment wear impurities in the production environment. If subsequent processes such as dehydration, drying, magnetic separation and packaging are still carried out in an open environment, the purified quartz sand may be contaminated again, affecting the stability of the finished product quality. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of easy contamination during process transfer and low efficiency of acid washing and separation in the prior art, and to propose a continuous high-purity quartz sand roasting and purification production line and process method.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a continuous high-purity quartz sand roasting and purification production line, comprising a pretreatment zone and a clean purification and packaging zone separated from the pretreatment zone, which are connected sequentially along the material conveying direction; The pretreatment area includes a coarse crushing and washing unit, a high-temperature roasting unit, a pure water cooling and conveying unit, a crushing and screening unit, and a first magnetic separation unit arranged in sequence. The discharge end of the high-temperature roasting unit is directly connected to the inlet end of the pure water cooling and conveying unit, so that the roasted hot quartz stone enters the pure water for rapid cooling without falling to the ground and is then conveyed to the rear. The clean purification and packaging area is equipped with a wet purification unit, a drying unit, a second magnetic separation unit and a packaging unit connected in sequence, and the above units are connected by a closed conveying mechanism. The wet purification unit includes a flotation device, a double-cone dynamic acid washing reactor group and a dehydration device arranged in sequence. The double-cone dynamic acid washing reactor group has a rotary acid washing and compressed air drainage structure.

[0008] A continuous high-purity quartz sand roasting and purification process is also provided, implemented using the aforementioned continuous high-purity quartz sand roasting and purification production line, including the following steps: S1: The raw quartz stone is cleaned and crushed and then roasted at high temperature. The roasted hot quartz stone is directly cooled in pure water without touching the ground. S2: The quartz stone after rapid cooling is crushed and sieved to obtain quartz sand within a predetermined particle size range, and the quartz sand is pre-magnetically separated to remove impurities. S3: The pre-magnetically separated quartz sand is sent to the clean purification and packaging area, where it is sequentially subjected to flotation to remove impurities and double-cone dynamic acid washing for deep purification. S4: The quartz sand after deep purification by double-cone dynamic acid washing is dehydrated, dried and then subjected to terminal magnetic separation to remove impurities; S5: The quartz sand after terminal magnetic separation and impurity removal is sent to the packaging unit for packaging through a closed conveyor mechanism in the clean purification and packaging area.

[0009] Preferably, in step S1: the cleaned and crushed raw quartz stone is fed into a high-temperature roasting unit and roasted at 900-1100°C, and held at the set roasting temperature for 30-120 minutes; the roasted hot quartz stone is directly fed into a pure water cooling tank for rapid cooling without natural cooling, ground stacking, or external temporary storage, wherein the pure water temperature is 10-30°C, the rapid cooling time is 5-20 minutes, and the solid-liquid ratio of quartz stone to pure water is 1:3-1:8 kg / L; the rapidly cooled quartz stone is then fed into the crushing and screening process by a lifting and conveying mechanism.

[0010] Preferably, S2: The quartz stone after rapid cooling is crushed and screened using a square gyratory screen to obtain quartz sand with a particle size of 40-120 mesh (corresponding to 125-380μm); the coarse particles screened out are returned to the crushing equipment for re-crushing through the return material mechanism, and the quartz sand that meets the particle size requirements enters the first magnetic separation unit for pre-magnetic separation and impurity removal.

[0011] Preferably, S3: The pre-magnetically separated quartz sand is sent to the clean purification and packaging area, where it is first subjected to flotation to remove impurities, and then sent to a double-cone dynamic acid washing reactor for deep acid washing purification; the acid solution includes hydrofluoric acid, hydrochloric acid and sulfuric acid, which are prepared in a volume ratio of 1:3:1, wherein the concentration of hydrofluoric acid is 5% to 10%, the concentration of hydrochloric acid is 10% to 20%, and the concentration of sulfuric acid is 5% to 15%; the solid-liquid ratio of quartz sand to acid solution is 1:2 to 1:5 (kg / L), the acid washing temperature is 60 to 90°C, the acid washing time is 2 to 8 hours, and the double-cone reactor rotates at a speed of 3 to 12 r / min.

[0012] After pickling, compressed air or nitrogen is introduced into the double-cone reactor through the air inlet, so that the acid solution enters the drain channel through the filter structure and is discharged from the acid outlet; then the double-cone reactor is tilted to discharge the pickled quartz sand.

[0013] The beneficial effects of the technical solution provided by this invention include at least the following:

[0014] (1) By directly connecting the discharge end of the high-temperature calcination unit to the feed end of the pure water cooling and conveying unit, the calcined hot quartz stone is rapidly cooled in pure water and then conveyed to the rear without natural cooling, ground stacking and external temporary storage. This can reduce the chance of hot quartz stone coming into contact with external pollutants during the transportation process.

[0015] Meanwhile, the calcined quartz generates thermal stress under temperature difference, which is conducive to the formation of microcracks on and inside the quartz. This exposes some impurities located near inclusions, grain boundaries, or existing microcracks, and provides mass transfer channels for subsequent flotation and acid washing processes. This is beneficial for subsequent crushing, screening, and impurity removal, thus increasing the leaching rate of inclusion impurities and improving the purity of the final quartz sand.

[0016] (2) By setting up a wet purification unit, a drying unit, a second magnetic separation unit and a packaging unit in the clean purification and packaging area, and connecting the above units through a closed conveying mechanism, the present invention can reduce the risk of secondary pollution of the deeply purified quartz sand during the dehydration, drying, terminal magnetic separation and packaging process, which is conducive to improving the quality stability of the finished quartz sand.

[0017] (3) The present invention uses a double-cone dynamic acid washing reactor group for deep purification by acid washing, and the double-cone reactor body rotates during the acid washing process, which enables the quartz sand particles to continuously turn and disperse in the reactor body, so that the solid-liquid contact interface on the surface of the quartz sand particles is constantly renewed, reducing local deposition, agglomeration or uneven contact, and facilitating the acid solution to enter the microcracks formed by rapid cooling and contact the impurities exposed therein, thereby promoting the mass transfer and leaching reaction between the acid solution and the impurities.

[0018] (4) After pickling, the present invention introduces gas into the double conical vessel, so that the acid liquid enters the discharge channel through the filter structure and is discharged from the acid outlet, which can complete the initial solid-liquid separation of acid liquid and quartz sand in the reactor. By further tilting the double conical vessel to discharge quartz sand, the repeated transfer of the pickled sand between the reaction equipment and the solid-liquid separation equipment can be reduced, and it is beneficial to connect the wet purification process with the subsequent dehydration process. Attached Figure Description

[0019] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the production line process provided in an embodiment of the present invention;

[0021] Figure 2 The above is an overall flowchart of the method provided in the embodiments of the present invention. Detailed Implementation

[0022] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a continuous high-purity quartz sand roasting and purification production line and process method proposed according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0024] The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0025] The following description, in conjunction with the accompanying drawings, details a specific scheme for a continuous high-purity quartz sand roasting and purification production line and process provided by the present invention. The present invention aims to provide a production line and process suitable for the continuous purification of high-purity quartz sand, so as to reduce the transfer contamination of quartz sand after roasting, after wet purification and before packaging, and to improve the connection stability between each purification process.

[0026] Please see Figures 1 to 2This invention illustrates a continuous high-purity quartz sand roasting and purification production line provided by an embodiment of the present invention, comprising a pretreatment zone 100 and a clean purification and packaging zone 200 separated from the pretreatment zone 100, which are connected sequentially along the material conveying direction. The pretreatment zone 100 includes a coarse crushing and washing unit 1, a high-temperature roasting unit 2, a pure water cooling and conveying unit 3, a crushing and screening unit 4, and a first magnetic separation unit 5 arranged sequentially. The discharge end of the high-temperature roasting unit 2 is directly connected to the inlet end of the pure water cooling and conveying unit 3, so that the roasted hot quartz stone enters the pure water for rapid cooling without falling to the ground and is then conveyed to the rear. The clean purification and packaging area 200 is equipped with a wet purification unit 6, a drying unit 7, a second magnetic separation unit 8 and a packaging unit 9 connected in sequence, and the above units are connected by a closed conveying mechanism. The wet purification unit 6 includes a flotation device, a double-cone dynamic acid washing reactor group and a dehydration device arranged in sequence. The double-cone dynamic acid washing reactor group has a rotary acid washing and compressed air drainage structure.

[0027] Specifically, the pretreatment zone 100 refers to the area used for rough processing and preliminary impurity removal of quartz raw materials, which may include processing steps such as washing, crushing, roasting, rapid cooling, pulverizing, screening and pre-magnetic separation.

[0028] The clean purification and packaging area 200 is a region used for further purification, drying, final impurity removal and packaging of pretreated quartz sand. It is separated from the pretreatment area 100 to reduce the entry of dust, debris or other impurities generated during the initial rough processing into the subsequent purification and packaging area.

[0029] "No grounding" means that after the hot quartz stone is discharged from the high-temperature roasting unit 2, it does not go through ground stacking, open temporary storage or manual transfer, but directly enters the pure water cooling and conveying unit 3.

[0030] Enclosed conveying mechanisms can be enclosed pipelines, enclosed screw conveyors, enclosed belt conveyors, enclosed bucket elevators, or other conveying structures that can reduce the degree of material exposure.

[0031] It is worth noting that the pretreatment area 100 and the clean purification and packaging area 200 can be separated by walls, partitions, clean doors, air showers, local sealed passages or other isolation structures. The clean purification and packaging area 200 does not need to be limited to a specific cleanliness level, as long as it can reduce the entry of dust, metal particles or other impurities compared to ordinary processing environments. The first magnetic separation unit 5 is located before wet purification and is used to pre-remove impurities from the crushed and screened quartz sand. The second magnetic separation unit 8 is located before packaging and is used to perform terminal impurity removal from the dried quartz sand. The two magnetic separations are located in different positions and have different impurity removal purposes.

[0032] In one specific implementation, natural quartz stone is first washed and coarsely crushed in the pretreatment zone 100 to form block material suitable for entering the high-temperature roasting unit 2. After the block quartz stone is roasted in the high-temperature roasting unit 2, it directly enters the pure water cooling and conveying unit 3 from the discharge end. The hot quartz stone is rapidly cooled in pure water and then sent to the crushing and screening unit 4. The crushed and screened quartz sand enters the clean purification and packaging zone 200 after pre-magnetic separation by the first magnetic separation unit 5. In the clean purification and packaging zone 200, flotation, double cone dynamic acid washing, dehydration, drying, second magnetic separation and packaging are completed in sequence. Through the above settings, the front-end coarse processing and the rear-end deep purification and packaging can form a relatively partitioned continuous processing process.

[0033] The high-temperature roasting unit 2 includes a continuous roasting furnace, which has a high-temperature roasting chamber, an in-furnace conveying mechanism, and a hot discharge port. The hot discharge port is connected to the pure water cooling conveying unit 3 through the material guiding channel; The pure water cooling and conveying unit 3 includes a pure water cooling tank and a lifting and conveying mechanism. The feeding section of the lifting and conveying mechanism is located inside the pure water cooling tank, and the discharge end of the lifting and conveying mechanism is connected to the crushing and screening unit 4.

[0034] Specifically, a continuous roasting furnace can be used to process block quartz stone through a high-temperature roasting chamber during transportation.

[0035] The conveying mechanism inside the furnace can be a high-temperature resistant conveyor belt, roller conveyor, pushing mechanism, chain plate mechanism, or other conveying structures suitable for high-temperature environments.

[0036] The hot discharge port is used to discharge the calcined quartz stone.

[0037] The material guide channel is used to guide hot quartz stone from the hot discharge port into the pure water cooling tank. It can be an inclined guide channel, a closed guide tube, a heat-resistant chute, or other material guide structures.

[0038] The pure water cooling tank is used to hold pure water and receive hot quartz stone, and the lifting and conveying mechanism is used to lift the quenched quartz stone from the pure water cooling tank and send it to the crushing and screening unit 4.

[0039] It is worth noting that the material guide channel can be made of a heat-resistant, wear-resistant material that does not easily introduce metal contamination into the quartz stone, or a wear-resistant lining can be installed on the surface in contact with the material. The pure water cooling tank can be equipped with a water inlet, a sewage outlet, an overflow outlet, or a sediment cleaning outlet to replenish pure water, discharge sediment, or maintain the water quality in the tank. The lifting and conveying mechanism can adopt chain plate lifting, bucket lifting, scraper lifting, or a conveying structure with baffles to ensure that the quartz stone after rapid cooling can stably leave the pure water cooling tank.

[0040] In one specific embodiment, the block quartz stone moves along the conveying mechanism inside the continuous roasting furnace and is heated when passing through the high-temperature roasting chamber. After being roasted, the hot quartz stone is discharged from the hot discharge port and falls directly into or is introduced into the pure water cooling tank through the material guide channel. After the hot quartz stone comes into contact with the pure water, it is rapidly cooled. Then, it is carried out of the pure water cooling tank by the lifting conveying mechanism and sent to the crushing and screening unit 4. This process reduces the need for the hot quartz stone to undergo natural cooling and external transfer after roasting.

[0041] The double-cone dynamic pickling reactor group includes at least one double-cone dynamic pickling reactor. The double-cone dynamic pickling reactor includes a support frame, a double-cone reactor body that can be rotatably and tiltably mounted on the support frame, a rotating shaft passing through the double-cone reactor body, and an inlet, a compressed air port, a discharge port, and an acid outlet mounted on the double-cone reactor body.

[0042] The rotating shaft is equipped with a drainage channel, and a filter structure is provided at one end of the rotating shaft located in the double-cone reactor body. The drainage channel is connected to the acid outlet.

[0043] Specifically, a double-cone reactor body refers to a structure in which the entire reactor body or the main containing part is constricted at both ends and relatively expanded in the middle. This structure can promote the mixing of quartz sand slurry and acid during rotation.

[0044] The support frame is used to support the double-cone vessel. The rotating shaft is used to support and drive the double-cone vessel to rotate.

[0045] The feed port is used to add quartz sand slurry and acid, the air pressure port is used to introduce gas into the reactor body, the discharge port is used to discharge the pickled quartz sand, and the acid discharge port is used to discharge the pickling waste liquid.

[0046] The filter structure is used to block quartz sand particles from entering the drainage channel during acid discharge, allowing the acid to pass through the filter structure into the drainage channel and then be discharged from the acid outlet.

[0047] It is worth noting that the filter structure can be a filter screen, sieve plate, filter cylinder, filter cover or other structure with liquid-solid separation function. The pore size or gap size of the filter structure can be selected according to the particle size of the quartz sand to reduce the discharge of quartz sand with acid. The inner wall of the double conical reactor can be lined with an acid-resistant, wear-resistant and non-contaminating quartz sand lining material. The air pressure port can be connected to an air source pipeline and a control valve so that gas can be introduced into the reactor after pickling to assist in the discharge of acid.

[0048] In one specific embodiment, the flotation-processed quartz sand slurry enters a double-cone reactor through the feed inlet, and acid is added inside the reactor. The double-cone reactor rotates around the rotating shaft under the action of the drive mechanism, causing the quartz sand particles and acid to repeatedly tumble and come into contact. After acid washing, gas is introduced into the reactor through the air pressure port, and the acid enters the drain channel inside the rotating shaft through the filter structure and is discharged from the acid outlet. After the acid is discharged, the double-cone reactor tilts, and the acid-washed quartz sand is discharged from the discharge port and enters the subsequent dewatering equipment.

[0049] The double-cone dynamic acid washing reactor group includes a first double-cone dynamic acid washing reactor 61 and a second double-cone dynamic acid washing reactor 62 arranged in parallel. The first double-cone dynamic acid washing reactor 61 and the second double-cone dynamic acid washing reactor 62 are respectively connected to the flotation equipment and the dewatering equipment to alternately perform feeding, acid washing reaction, acid discharge and material discharge.

[0050] Specifically, the parallel setup means that both the first double-cone dynamic pickling reactor 61 and the second double-cone dynamic pickling reactor 62 can receive quartz sand slurry from the flotation equipment and can send the pickled quartz sand to the dewatering equipment.

[0051] Alternating feeding, pickling reaction, acid discharge, and material discharge means that when one of the double-cone dynamic pickling reactors is in the pickling reaction state, the other double-cone dynamic pickling reactor can be in the feeding, acid discharge, material discharge, or preparation state, thereby better connecting the wet purification process with the preceding and following processes.

[0052] It is worth noting that a feed distribution valve, a discharge switching valve, an acid supply pipeline, an acid discharge pipeline, and a control system can be installed between the first double-cone dynamic pickling reactor 61 and the second double-cone dynamic pickling reactor 62. The control system can control the opening and closing of valves and the operation of drive mechanisms according to the working status of each reactor. The number of reactors connected in parallel is not limited to two. In cases where the capacity requirement is high or the pickling residence time is long, three or more double-cone dynamic pickling reactors can also be installed.

[0053] In one specific implementation, when the first double-cone dynamic pickling reactor 61 receives the flotation-processed quartz sand slurry and enters the pickling reaction state, the second double-cone dynamic pickling reactor 62 can complete the compressed air discharge and tilting discharge of the previous batch of material. After the first double-cone dynamic pickling reactor 61 completes the pickling, the second double-cone dynamic pickling reactor 62 can be re-fed, and the first double-cone dynamic pickling reactor 61 enters the discharge state. By alternating operation, the impact of intermittent operation of a single reactor on the continuity of the entire line can be reduced.

[0054] The first magnetic separation unit 5 and the second magnetic separation unit 8 both include two electromagnetic separators connected in series along the material conveying direction.

[0055] Specifically, the two electromagnetic separators in the first magnetic separation unit 5 are used for continuous pre-magnetic separation of the crushed and screened quartz sand, and the two electromagnetic separators in the second magnetic separation unit 8 are used for terminal magnetic separation of the dried quartz sand.

[0056] The series configuration refers to the process where materials pass through two electromagnetic separators in sequence, enabling them to complete two stages of magnetic impurity removal.

[0057] The first magnetic separation unit 5 is mainly used to reduce the content of magnetic impurities before entering the flotation and pickling processes, while the second magnetic separation unit 8 is mainly used to further remove magnetic impurities that may be mixed in during the subsequent processing before packaging.

[0058] It is worth noting that the two electromagnetic separators can use the same or different magnetic separation intensities, feeding methods and impurity removal methods. The parts of the electromagnetic separator that come into contact with the material can be made of wear-resistant, easy-to-clean and non-metallic contaminants. The first magnetic separation unit 5 and the second magnetic separation unit 8 can be configured with independent dust removal, collection or impurity removal structures so that the separated impurities can be discharged in a timely manner.

[0059] In one specific implementation, the crushed and screened quartz sand first enters the first magnetic separation unit 5, and then passes through two electromagnetic separators in sequence. Impurities that are more easily adsorbed or separated by the magnetic field are discharged. After completing the pre-magnetic separation, the quartz sand enters the flotation equipment. After drying, the quartz sand enters the second magnetic separation unit 8, and then passes through two electromagnetic separators in sequence for final magnetic separation. After that, it enters the packaging unit 9. Through the two magnetic separations, impurity removal nodes can be formed before wet purification and before packaging, respectively.

[0060] This invention also provides a continuous high-purity quartz sand roasting and purification process, characterized by being implemented using the aforementioned continuous high-purity quartz sand roasting and purification production line, and comprising the following steps:

[0061] S1: The raw quartz stone is cleaned and crushed, then roasted at high temperature. The roasted hot quartz stone is then directly cooled in pure water without touching the ground.

[0062] In step S1, the hot quartz stone does not undergo natural cooling, ground stacking, or external temporary storage during the period from high-temperature calcination to entering pure water rapid cooling;

[0063] After the hot quartz stone enters the pure water, it is conveyed out of the pure water by the lifting and conveying mechanism and enters the crushing and screening process.

[0064] Specifically, the raw quartz stone can first be washed to remove surface mud and adhering substances, and then crushed into block quartz stone suitable for firing by manual or mechanical means.

[0065] High-temperature roasting is used for heat treatment of bulk quartz.

[0066] Hot quartz stone is directly cooled in pure water without touching the ground. This means that after the quartz stone is discharged from the calcination equipment, it is directly put into the pure water cooling tank through the material guide channel or other conveying structure, without being piled up on the ground, temporarily stored in the open, or manually transferred.

[0067] It is worth noting that the water in the pure water cooling tank can be replenished, filtered, or replaced according to production conditions to reduce new contamination of the materials during the cooling process. When hot quartz enters the pure water cooling tank, a guide channel can be used to control the direction of material flow, reducing splashing or scattering. The lifting and conveying mechanism can be equipped with a drain section to reduce the amount of free water carried on the surface of the quartz after it is lifted from the pure water.

[0068] In one specific embodiment, the cleaned and coarsely crushed block quartz is fed into a continuous roasting furnace for roasting. After roasting, the hot quartz is discharged from the hot discharge port and directly enters the pure water cooling tank through the material guide channel. After being rapidly cooled in the pure water, the quartz is carried out of the pure water cooling tank by the lifting and conveying mechanism and sent to the crushing and screening unit 4. This embodiment can reduce the exposure time of the roasted quartz in the ordinary environment.

[0069] When performing step S1, attention should be paid to the connection status between the high-temperature roasting unit 2, the material guiding channel and the pure water cooling and conveying unit 3, so that the hot quartz can stably enter the pure water cooling tank. Attention should also be paid to the water level and water quality of the pure water cooling tank, so that the quartz can be rapidly cooled and conveyed after entering the pure water. The sludge after entering the pure water cooling tank can be discharged periodically according to production needs.

[0070] S2: The quartz stone after rapid cooling is crushed and sieved to obtain quartz sand within a predetermined particle size range, and the quartz sand is pre-magnetically separated to remove impurities.

[0071] In step S2, the crushed quartz sand is screened using a square gyratory screen 41, and the coarse particles screened out are returned to the crushing equipment for re-crushing.

[0072] Pre-magnetic separation is used to remove magnetic impurities before flotation, while terminal magnetic separation is used to remove magnetic impurities introduced during drying and conveying before packaging.

[0073] Specifically, crushing refers to further breaking down quartz stone after rapid cooling into quartz sand particles.

[0074] Screening refers to using screening equipment to classify the crushed quartz sand according to its particle size. Quartz sand that meets the predetermined particle size range enters the subsequent first magnetic separation unit 5, while coarse particles that do not meet the requirements are returned to the crushing equipment for re-crushing.

[0075] Pre-magnetic separation refers to the process of removing magnetic impurities or some metallic impurities from quartz sand through the first magnetic separation unit 5 before the quartz sand enters the flotation and acid washing processes.

[0076] It is worth noting that the square gyratory screen 41 can be equipped with multiple layers of screens to screen according to different particle size requirements. The screen material can be selected according to the cleanliness requirements of the product. The return material mechanism can adopt a closed conveying structure to reduce dust and external pollution during the return of coarse particles to the crushing equipment. The feeding of the first magnetic separation unit 5 should be as uniform as possible to improve the stability of magnetic separation.

[0077] In one specific embodiment, the quenched quartz stone enters the crushing equipment and is crushed to form quartz sand. The quartz sand enters the square gyratory screen 41 for screening. The quartz sand with qualified particle size enters the first magnetic separation unit 5. The coarse particles are returned to the crushing equipment through the coarse particle return port and the return material mechanism. After being processed by the first magnetic separation unit 5, some magnetic impurities in the quartz sand are removed, and then it enters the wet purification unit 6 in the clean purification and packaging area 200.

[0078] When performing step S2, attention should be paid to the condition of the screen of the screening equipment to avoid screen damage or blockage affecting particle size control; at the same time, attention should be paid to the sealing and conveying stability of the return material mechanism to reduce dust escape. When performing pre-magnetic separation, the feed should be adjusted according to the material flow rate and particle size to ensure that the quartz sand can pass through the electromagnetic separator more evenly.

[0079] S3: The pre-magnetically separated quartz sand is sent to the clean purification and packaging area 200 for flotation to remove impurities and double cone dynamic acid washing for deep purification.

[0080] In step S3, the dual-cone dynamic acid washing depth purification includes the following processes:

[0081] Quartz sand slurry and acid solution are fed into the double-cone dynamic pickling reactor body;

[0082] The double-cone reactor body is driven to rotate, so that the quartz sand slurry comes into dynamic contact with the acid solution and undergoes an acid washing reaction;

[0083] After the pickling reaction is completed, gas is introduced into the double-cone reactor through the gas pressure port, so that the acid solution enters the drainage channel through the filtration structure and is discharged from the acid outlet.

[0084] After the acid is discharged, the double-cone vessel is tilted to discharge the acid-washed quartz sand.

[0085] Specifically, flotation for impurity removal refers to mixing pre-magnetically separated quartz sand with water and flotation agent, and removing some non-magnetic impurities or associated impurities through flotation.

[0086] The double-cone dynamic acid washing deep purification refers to sending the flotation quartz sand slurry and acid solution into the double-cone dynamic acid washing reactor, where the material and acid solution are dynamically contacted by the rotation of the reactor body, and the acid solution is discharged after acid washing using a compressed air discharge structure.

[0087] Gas-assisted drainage refers to introducing gas into the reactor body, allowing the acid to pass through the filtration structure into the drainage channel and be discharged from the acid outlet.

[0088] It is worth noting that the type, concentration, reaction time, and reaction temperature of the acid solution can be selected according to the characteristics of the quartz sand raw material and the requirements of the target product, and are not limited to a certain fixed parameter. The filter structure plays a role in blocking quartz sand particles during the acid discharge process. Therefore, the appropriate filter pore size or filter form should be selected in combination with the quartz sand particle size. The rotation speed of the double cone reactor can be adjusted according to the slurry flow state to reduce material deposition or insufficient local contact.

[0089] In one specific implementation, the pre-magnetically separated quartz sand is first mixed with water and flotation agent in a flotation device. After flotation, it enters a double-cone dynamic acid washing reactor. After the quartz sand slurry and acid enter the double-cone reactor, the reactor begins to rotate. The quartz sand particles tumble in the reactor and come into contact with the acid. After the reaction is completed, gas is introduced through the gas pressure port. The acid enters the drainage channel in the rotating shaft through the filter structure and is discharged from the acid outlet. Then the reactor tilts, and the acid-washed quartz sand is discharged and enters the dewatering device.

[0090] When performing step S3, attention should be paid to ensuring that the concentration of the quartz sand slurry after flotation matches the feeding capacity of the double-cone dynamic acid washing reactor. During the acid washing operation, attention should be paid to the order of acid addition, reactor rotation, compressed air discharge, and tilting discharge. During the acid discharge process, the filter structure should be kept unobstructed to reduce the possibility of quartz sand entering the discharge channel with the acid.

[0091] S4: The quartz sand after deep purification by double-cone dynamic acid washing is dehydrated, dried, and subjected to terminal magnetic separation to remove impurities.

[0092] Specifically, dehydration refers to reducing the moisture content in acid-washed quartz sand through centrifugation, filtration, pressure filtration, or other solid-liquid separation methods.

[0093] Drying refers to heating and drying dehydrated quartz sand to bring it to a state suitable for subsequent magnetic separation and packaging.

[0094] Terminal magnetic separation for impurity removal refers to the use of the second magnetic separation unit 8 to remove magnetic impurities from the dried quartz sand before packaging.

[0095] It is worth noting that the dehydration equipment and drying unit 7 can be set up in the clean purification and packaging area 200 and connected by a closed conveying mechanism. The heat source form and temperature control method during the drying process can be selected according to production needs. Before the dried quartz sand enters the second magnetic separation unit 8, a buffer silo or uniform feeding mechanism can be set up to improve the processing stability of the terminal magnetic separation.

[0096] In one specific implementation, the pickled quartz sand is discharged from the double-cone dynamic pickling reactor and enters the dehydration equipment. After removing some of the moisture, it enters the drying unit 7 through a closed conveying mechanism. After drying, the quartz sand is cooled or buffered and then enters the second magnetic separation unit 8. It passes through two electromagnetic separators in sequence for terminal magnetic separation to remove impurities. The quartz sand after terminal magnetic separation is then sent to the packaging unit 9 through a closed conveying mechanism.

[0097] When performing step S4, attention should be paid to the acid discharge situation before the material enters the dewatering equipment after pickling, so as to reduce the impact of residual liquid on the subsequent drying process. After drying, the material should be exposed to the ordinary environment as little as possible, and the terminal magnetic separation equipment should be kept clean to reduce the contamination of the material by the magnetic separation process itself.

[0098] S5: The quartz sand after terminal magnetic separation and impurity removal is sent to the packaging unit 9 for packaging in the clean purification and packaging area 200 through a closed conveyor mechanism.

[0099] Specifically, the packaging unit 9 may include a metering device, a feeding device, a packaging bag positioning device, a sealing device, or other packaging auxiliary devices.

[0100] The enclosed conveying mechanism is used to transport the quartz sand after terminal magnetic separation from the second magnetic separation unit 8 to the packaging unit 9, reducing the material's contact with the external environment during the conveying process.

[0101] It is worth noting that the packaging material can be selected according to the cleanliness requirements of high-purity quartz sand. The packaging container can be cleaned before packaging. During the packaging process, local dust removal, negative pressure collection or clean air supply can be used to reduce the impact of dust. A buffer silo can be set between the packaging unit 9 and the second magnetic separation unit 8 to stabilize the packaging cycle.

[0102] In one specific embodiment, the quartz sand processed by the second magnetic separation unit 8 enters the closed conveying mechanism and is sent to the packaging unit 9. The packaging unit 9 measures, bags, and seals the quartz sand. The packaged finished product is output from the clean purification and packaging area 200. Since the terminal magnetic separation and packaging are both located in the clean purification and packaging area 200 and are connected by the closed conveying mechanism, it is beneficial to reduce secondary contamination of the materials before packaging.

[0103] When performing step S5, attention should be paid to the sealing of the connection between the packaging unit 9 and the enclosed conveyor mechanism, and the cleanliness of the packaging container, the discharge port and the sealing area should be noted. Dust generated during the packaging process can be treated by dust removal or collection structures to reduce the impact on the environment within the clean purification packaging area 200.

[0104] In steps S3 to S5, flotation for impurity removal, double-cone dynamic acid washing for deep purification, dehydration, drying, terminal magnetic separation for impurity removal, and packaging are all carried out in the clean purification and packaging area 200. The quartz sand after double-cone dynamic acid washing for deep purification is transported by a closed conveying mechanism during the dehydration, drying, terminal magnetic separation for impurity removal, and packaging processes.

[0105] Specifically, the clean purification and packaging area 200 is used to carry the subsequent processing steps after wet purification. It can reduce the possibility of external impurities entering through spatial isolation, local enclosure, clean air supply, dust collection or positive pressure control.

[0106] The enclosed conveyor system is used to transport quartz sand between downstream processing units, keeping the quartz sand with a low degree of exposure during dewatering, drying, terminal magnetic separation and packaging.

[0107] It is worth noting that the clean purification and packaging area 200 is not limited to a large open-plan cleanroom; it can also be a clean processing area formed by local clean hoods, clean passages, enclosed equipment shell structures, or combinations of multiple local clean units. The closed conveying mechanism can be selected in different forms depending on the material's state. For example, wet materials can use closed pipes or sealed conveying troughs, while dry materials can use closed screw conveyors, sealed bucket elevators, or closed pneumatic conveying structures.

[0108] In one specific implementation, after entering the clean purification and packaging area 200, the quartz sand sequentially passes through a flotation device, a double-cone dynamic acid washing reactor group, a dewatering device, a drying unit 7, a second magnetic separation unit 8, and a packaging unit 9. The devices are connected by a closed conveyor mechanism, and local clean hoods or isolation structures are set outside the devices to reduce the contact between the deeply purified quartz sand and the ordinary workshop environment before entering the packaging. This implementation method is beneficial to maintaining the cleanliness of the subsequent processing and improving the stability of the finished product quality.

[0109] Table 1. Two-factor, two-level orthogonal combination experiment.

[0110] Example 1 Hot pure water rapid cooling Dual-cone dynamic pickling Complete solution of the present invention Comparative Example 1 Natural cooling Dual-cone dynamic pickling Verify the effect of rapid cooling Comparative Example 2 Hot pure water rapid cooling Static soaking and pickling Verification of dynamic pickling effect Comparative Example 3 Natural cooling Static soaking and pickling Benchmark conventional scheme

[0111] Table 2 Data Table of Testing Items

[0112] raw ore 99.42 185 312 46 543 Comparative Example 1 99.960 21 45 8 74 Comparative Example 2 99.971 14 31 6 51 Comparative Example 3 99.952 28 52 11 91 Example 1 99.995 5 12 2 19

[0113] Table 2 shows the impurity removal rate. Calculations should be performed using the following formula: ; in, The content of a certain impurity before processing, This represents the content of the impurity after processing.

[0114] As shown in Table 2, compared with the comparative examples, the contents of major impurities such as Fe, Al and Ti in the quartz sand obtained by the embodiments of the present invention are further reduced, and the total impurity content is reduced to 19 mg / kg.

[0115] Hot pure water quenching can promote the formation of microcrack networks in quartz particles and increase the exposure of inclusion impurities; dual-cone dynamic acid washing can enhance the mass transfer process between acid and quartz particles and improve the leaching efficiency of impurities; the synergistic effect of the two technologies further improves the purification effect of quartz sand, verifying that the continuous roasting quenching and dynamic acid washing process of this invention has a significant purification effect.

[0116] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A continuous high-purity quartz sand roasting and purification production line, characterized in that, It includes a pre-processing zone (100) connected sequentially along the material conveying direction and a clean purification and packaging zone (200) separated from the pre-processing zone (100). The pretreatment zone (100) includes a coarse crushing and washing unit (1), a high-temperature roasting unit (2), a pure water cooling and conveying unit (3), a crushing and screening unit (4), and a first magnetic separation unit (5) arranged in sequence. The discharge end of the high-temperature roasting unit (2) is directly connected to the feed end of the pure water cooling and conveying unit (3), so that the roasted hot quartz stone enters the pure water for rapid cooling without falling to the ground and is then conveyed to the rear. The clean purification and packaging area (200) is provided with a wet purification unit (6), a drying unit (7), a second magnetic separation unit (8) and a packaging unit (9) connected in sequence, and the above units are connected by a closed conveying mechanism; The wet purification unit (6) includes a flotation device, a double-cone dynamic acid washing reactor group and a dehydration device arranged in sequence. The double-cone dynamic acid washing reactor group has a rotary acid washing and compressed air drainage structure.

2. The continuous high-purity quartz sand roasting and purification production line according to claim 1, characterized in that: The high-temperature roasting unit (2) includes a continuous roasting furnace, which has a high-temperature roasting chamber, an in-furnace conveying mechanism and a hot discharge port; The hot discharge port is connected to the pure water cooling conveying unit (3) through a material guiding channel; The pure water cooling conveying unit (3) includes a pure water cooling tank and a lifting conveying mechanism. The feeding section of the lifting conveying mechanism is located in the pure water cooling tank, and the discharge end of the lifting conveying mechanism is connected to the crushing and screening unit (4).

3. The continuous high-purity quartz sand roasting and purification production line according to claim 1, characterized in that: The double-cone dynamic pickling reactor group includes at least one double-cone dynamic pickling reactor. The double-cone dynamic pickling reactor includes a support frame, a double-cone reactor body that can be rotatably and tiltably arranged on the support frame, a rotating shaft passing through the double-cone reactor body, and a feed port, a compressed air port, a discharge port and an acid outlet arranged on the double-cone reactor body. The rotating shaft is provided with a drainage channel, and a filter structure is provided at one end of the rotating shaft located in the double-cone reactor body. The drainage channel is connected to the acid outlet.

4. The continuous high-purity quartz sand roasting and purification production line according to claim 3, characterized in that: The double-cone dynamic acid washing reactor group includes a first double-cone dynamic acid washing reactor (61) and a second double-cone dynamic acid washing reactor (62) arranged in parallel. The first double-cone dynamic acid washing reactor (61) and the second double-cone dynamic acid washing reactor (62) are respectively connected to the flotation equipment and the dewatering equipment to alternately perform feeding, acid washing reaction, acid discharge and material discharge.

5. The continuous high-purity quartz sand roasting and purification production line according to claim 1, characterized in that: Both the first magnetic separation unit (5) and the second magnetic separation unit (8) include two electromagnetic separators connected in series along the material conveying direction.

6. A continuous high-purity quartz sand roasting and purification process, characterized in that, The continuous high-purity quartz sand roasting and purification production line according to any one of claims 1 to 5 is implemented, comprising the following steps: S1: The raw quartz stone is cleaned and crushed and then roasted at high temperature. The roasted hot quartz stone is directly cooled in pure water without touching the ground. S2: The quartz stone after rapid cooling is crushed and sieved to obtain quartz sand within a predetermined particle size range, and the quartz sand is pre-magnetically separated to remove impurities. S3: The pre-magnetically separated quartz sand is sent to the clean purification and packaging area (200) for flotation to remove impurities and double cone dynamic acid washing for deep purification. S4: The quartz sand after deep purification by double-cone dynamic acid washing is dehydrated, dried and then subjected to terminal magnetic separation to remove impurities; S5: The quartz sand after terminal magnetic separation is sent to the packaging unit (9) for packaging in the clean purification and packaging area (200) through a closed conveyor mechanism.

7. The continuous high-purity quartz sand roasting and purification process according to claim 6, characterized in that: In step S1, the hot quartz stone does not undergo natural cooling, ground stacking, or external temporary storage during the period from high-temperature calcination to entering pure water rapid cooling; After the hot quartz stone enters the pure water, it is conveyed out of the pure water by the lifting and conveying mechanism and enters the crushing and screening process.

8. The continuous high-purity quartz sand roasting and purification process according to claim 6, characterized in that: In step S3, the dual-cone dynamic acid washing depth purification includes the following processes: Quartz sand slurry and acid solution are fed into the double-cone dynamic pickling reactor body; The double-cone reactor body is driven to rotate, so that the quartz sand slurry comes into dynamic contact with the acid solution and undergoes an acid washing reaction; After the pickling reaction is completed, gas is introduced into the double-cone reactor through the gas pressure port, so that the acid solution enters the drainage channel through the filtration structure and is discharged from the acid outlet. After the acid is discharged, the double-cone vessel is tilted to discharge the acid-washed quartz sand.

9. The continuous high-purity quartz sand roasting and purification process according to claim 6, characterized in that: In steps S3 to S5, flotation for impurity removal, double-cone dynamic acid washing for deep purification, dehydration, drying, terminal magnetic separation for impurity removal and packaging are all carried out in the clean purification and packaging area (200), and the quartz sand after double-cone dynamic acid washing for deep purification is transported by a closed conveying mechanism during the dehydration, drying, terminal magnetic separation for impurity removal and packaging processes.

10. The continuous high-purity quartz sand roasting and purification process according to claim 6, characterized in that: In step S2, the crushed quartz sand is screened using a square gyratory screen (41), and the coarse particles screened out are returned to the crushing equipment for re-crushing. The pre-magnetic separation is used to remove magnetic impurities before flotation, and the terminal magnetic separation is used to remove magnetic impurities introduced during drying and conveying before packaging.

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