Special mechanism sand production process

Abstract

This invention provides a special manufactured sand production process, with the following specific steps: Step 1, fine crushing; Step 2, finished product screening and powder selection; Step 3, special sand mixing and shipping. In this invention, the output from the vertical roller mill sand making machine undergoes primary powder selection. After selecting sand with a particle size <0.15mm, finished product screening is performed, reducing the screening load on the high-frequency vibrating screen, reducing screen hole clogging, and improving the screening efficiency of the high-frequency vibrating screen. Next, secondary powder selection is performed on the output with a particle size <0.6mm after finished product screening, again selecting sand with a particle size <0.15mm. The primary and secondary powder selections ensure that sand with a particle size <0.15mm is selected. Finally, a targeted tertiary powder selection is performed, and the output with a particle size <0.075mm is stored in a stone powder silo. This invention sets up a process flow that combines a high-frequency vibrating screen as the finished product screen with tertiary powder selection, effectively ensuring the product quality of special manufactured sand and laying the foundation for adjustable gradation of special manufactured sand.

Description

Technical Field

[0001] This invention relates to the field of manufactured sand processing and production, and specifically to a special manufactured sand production process. Background Technology

[0002] Manufactured sand is an indispensable building material. With the rapid development of my country's economy and the continuous expansion of infrastructure construction, readily available and high-quality natural river sand has become the preferred choice. However, long-term large-scale mechanized sand mining has not only drastically reduced natural river sand resources but also posed a serious threat to the river's ecological environment and safety.

[0003] Manufactured sand refers to sand obtained by processing large stones through coarse, medium, and fine crushing and screening using various specialized equipment. Compared to natural river sand, manufactured sand has abundant sand sources, meaning the sources of stone used for its production are quite diverse, such as unweathered rocks with suitable hardness, including bluestone, granite, limestone, and basalt. Manufactured sand also boasts mature processing equipment and production processes, producing products with excellent particle shape, uniform and adjustable particle size to meet various sand application needs. In today's building materials market, manufactured sand has gradually surpassed natural river sand to achieve a dominant position.

[0004] With increasing demands for building functionality and continuous technological innovation in the building materials industry, specialty mortars have gradually come into the public eye. Specialty mortars are designed for specific requirements such as thermal insulation, sound absorption, waterproofing, corrosion resistance, radiation protection, decoration, and bonding. Currently, they are widely used in interior and exterior wall insulation and interior and exterior decoration. Representative specialty mortars include tile adhesives, grouts, waterproof coatings, thermal insulation mortars, self-leveling mortars, grouting materials, decorative mortars, and gypsum plastering mortars. Specialty mortars represent an important direction in the development of new building materials, and market demand is growing rapidly. However, when mixing specialty mortars, ordinary manufactured sand has a relatively high proportion of coarse and fine particles and poor particle gradation, which cannot guarantee the excellent performance of the produced specialty mortar. Therefore, it is necessary to differentiate it from ordinary manufactured sand and produce artificial fine aggregates specifically for mixing specialty mortars—specialty manufactured sand.

[0005] Compared to ordinary manufactured sand, specialty manufactured sand has higher requirements for mesh size gradation, increasing the production difficulty. Currently, the technological process for producing specialty manufactured sand is not mature, resulting in quality issues such as numerous sharp edges and corners, and also leading to high energy consumption and production costs due to complex processing equipment and cumbersome processes. Therefore, this invention provides a specialty manufactured sand production process that simplifies existing processes while meeting the quality requirements of specialty manufactured sand, minimizing energy consumption and maximizing economic efficiency. Summary of the Invention

[0006] To overcome the current immature technology for producing specialty manufactured sand, which not only suffers from quality issues such as sharp edges and corners, but also suffers from high energy consumption and production costs due to complex processing equipment and cumbersome processes, this invention provides a specialty manufactured sand production process that simplifies the existing production process while meeting the quality requirements of specialty manufactured sand, thereby minimizing energy consumption and maximizing economic efficiency.

[0007] The technical solution adopted in this invention is as follows:

[0008] A special manufactured sand production process, the specific steps of which are as follows:

[0009] Step 1, fine crushing: materials with a particle size of 4.75-20mm are transported from the special sand intermediate silo to the vertical roller mill for crushing. The crushed materials then enter the primary powder classifier.

[0010] Step 2: Finished product screening and powder selection. After the material passes through the primary powder classifier, the output with a particle size >10mm is returned to the vertical roller mill for recycling and crushing, the output with a particle size <0.15mm enters the tertiary powder classifier, and the remaining output with a particle size of 0.15mm-10mm enters the high-frequency vibrating screen.

[0011] After passing through a high-frequency vibrating screen, the material is divided into three types of output: >2.36mm, 0.6mm-2.36mm, and <0.6mm. The output with a particle size >2.36mm is returned to the vertical roller mill for recycling and crushing. The sand with a particle size of 0.6mm-2.36mm is stored in the special sand finished product warehouse, and the aggregate with a particle size <0.6mm is sent to the secondary powder classifier.

[0012] After passing through the secondary classifier, the material with a particle size >0.15mm enters the special sand finished product warehouse II for storage; the material with a particle size <0.15mm enters the tertiary classifier.

[0013] After passing through the three-stage powder classifier, the material with a particle size >0.075mm is discharged into the special sand finished product silo for storage; the material with a particle size <0.075mm is discharged into the stone powder silo for storage.

[0014] Step 3: Special sand mixing and shipping. The output of the three special sand finished product warehouses is weighed by the weighing system corresponding to the bottom of the three warehouses to prepare special manufactured sand that meets various gradation requirements. The special sand is then mixed and shipped from the special sand mixing warehouse.

[0015] The primary air classifier includes at least a composite air classifier and a dust collector. The material crushed by the vertical roller mill enters the composite air classifier via a corresponding conveyor belt and elevator. The material with a particle size >10mm is transferred back to the vertical roller mill for recycling and sand making via the corresponding conveyor belt and elevator. The gas carrying the material enters the dust collector, which separates the material and gas. The material with a particle size <0.15mm enters the tertiary air classifier. The remaining material with a particle size of 0.15mm-10mm enters the high-frequency vibrating screen for screening.

[0016] The dust collector mentioned is a double-row cyclone dust collector.

[0017] The secondary air classifier includes at least a composite air classifier and a dust collector. After passing through a high-frequency vibrating screen, the material with a particle size <0.6mm enters the composite air classifier. The material with a particle size of 0.15mm-0.6mm is stored in the special sand finished product warehouse. After passing through the dust collector, the material with a particle size <0.15mm enters the tertiary air classifier through the corresponding conveyor belt and elevator.

[0018] The aforementioned three-stage air classifier is an internal circulation air classifier.

[0019] The high-frequency vibrating screens are multiple in number.

[0020] In step three, the two outlets at the lower end of the special sand mixing silo are respectively equipped with an electric sector valve and a humidifying mixer.

[0021] In step three, the materials in the special sand mixing silo are shipped out by an automatic loading machine.

[0022] The vertical roller mill sand making machine, primary air classifier, high-frequency vibrating screen, secondary air classifier, tertiary air classifier, three special sand finished product warehouses, special sand mixing warehouse and stone powder warehouse are all equipped with dust collectors.

[0023] The dust collectors are all connected to the stone powder silo, and a stone powder bulk loading machine is installed at the bottom of the stone powder silo.

[0024] The beneficial effects of this invention are:

[0025] In this invention, a vertical roller mill is selected for fine crushing, and a high-frequency vibrating screen is used as the finished product screen. Compared with a ball mill, the vertical roller mill avoids over-grinding when processing aggregates, has high grinding efficiency, produces uniformly graded output particles, and has less equipment wear; the high-frequency vibrating screen is suitable for classifying small particles, can screen materials with a particle size of 0.5mm-40mm, and has high screening efficiency.

[0026] In this invention, a process flow combining finished product screening and three-stage powder classification is set up, which effectively ensures the product quality of special manufactured sand and lays the foundation for adjustable gradation of special manufactured sand. After the material from the vertical roller mill sand making machine is discharged, it first undergoes primary powder classification. After selecting sand with a particle size <0.15mm, it is screened as finished product, which reduces the screening load of the high-frequency vibrating screen, reduces screen hole clogging, and improves the screening efficiency of the high-frequency vibrating screen. Next, secondary powder classification is performed on the discharged material with a particle size <0.6mm after finished product screening, and sand with a particle size <0.15mm is selected again. The primary and secondary powder classifications fully ensure that sand with a particle size <0.15mm is selected. Finally, a targeted tertiary powder classification is performed, and the discharged material with a particle size <0.075mm is stored in the stone powder silo.

[0027] In this invention, special manufactured sand that meets various gradation requirements can be prepared through the bottom weighing system of three special sand finished product warehouses, and then mixed and shipped from the special sand mixing warehouse. Attached Figure Description

[0028] The present invention will now be described in further detail with reference to the accompanying drawings.

[0029] Figure 1 This is a flow chart of the special manufactured sand production process provided by the present invention.

[0030] In the figure, the attached reference numerals are:

[0031] 1. Vertical roller mill sand making machine; 2. Compound air classifier I; 3. Dust collector I; 4. High frequency vibrating screen; 5. Compound air classifier II; 6. Dust collector II; 7. Internal circulation air classifier; 8. Stone powder silo; 9. Special sand finished product silo I; 10. Special sand finished product silo II; 11. Special sand finished product silo III; 12. Special sand mixing silo; 13. Stone powder bulk loading machine; 14. Quantitative feeder; 15. Electric sector valve; 16. Humidifying mixer; 17. Automatic loading machine. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0034] Example 1:

[0035] To overcome the current immature process of producing special manufactured sand, which not only suffers from quality problems such as numerous sharp edges and corners, but also from high energy consumption and production costs due to complex processing equipment and cumbersome processes, this invention provides... Figure 1 The process for producing special manufactured sand shown simplifies the existing production process while meeting the quality requirements of special manufactured sand, thereby minimizing energy consumption and improving economic efficiency.

[0036] A special manufactured sand production process, the specific steps of which are as follows:

[0037] Step 1, fine crushing: Material with a particle size of 4.75-20mm is transported from the special sand intermediate silo to the vertical roller mill sand making machine 1 for crushing. The crushed material enters the primary powder classifier.

[0038] Step 2: Finished product screening and powder selection. After the material passes through the primary powder selection equipment, the output with a particle size >10mm is returned to the vertical roller mill sand making machine 1 for recycling and crushing, the output with a particle size <0.15mm enters the tertiary powder selection equipment, and the remaining output with a particle size of 0.15mm-10mm enters the high-frequency vibrating screen 4.

[0039] After passing through the high-frequency vibrating screen 4, the material is divided into three types of discharge: >2.36mm, 0.6mm-2.36mm, and <0.6mm. Among them, the discharge with a particle size >2.36mm is returned to the vertical roller mill sand making machine 1 for recycling and crushing; the sand with a particle size of 0.6mm-2.36mm enters the special sand finished product warehouse 9 for storage; and the aggregate with a particle size <0.6mm enters the secondary powder classifier.

[0040] After passing through the secondary classifier, the material with a particle size >0.15mm is discharged into the special sand finished product warehouse II 10 for storage; the material with a particle size <0.15mm is discharged into the tertiary classifier.

[0041] After passing through the three-stage powder classifier, the material with a particle size >0.075mm is stored in the special sand finished product silo 311; the material with a particle size <0.075mm is stored in the stone powder silo 8.

[0042] Step 3: Special sand mixing and shipping. The output of the three special sand finished product warehouses is weighed by the weighing system corresponding to the bottom of the three warehouses to prepare special manufactured sand that meets various gradation requirements. The special sand is then mixed and shipped from the special sand mixing warehouse.

[0043] In this invention, a vertical roller mill is selected for fine crushing, and a high-frequency vibrating screen is used as the finished product screen. Compared with a ball mill, the vertical roller mill avoids over-grinding when processing aggregates, has high grinding efficiency, produces uniformly graded output particles, and has less equipment wear; the high-frequency vibrating screen is suitable for classifying small particles, can screen materials with a particle size of 0.5mm-40mm, and has high screening efficiency.

[0044] In this invention, a process flow combining finished product screening and three-stage powder classification is set up, which effectively ensures the product quality of special manufactured sand and lays the foundation for adjustable gradation of special manufactured sand. After the material is discharged from the vertical roller mill sand making machine, it first undergoes primary powder classification. After selecting sand with a particle size <0.15mm, it is screened as finished product, which reduces the screening load of the high-frequency vibrating screen, reduces screen hole clogging, and improves the screening efficiency of the high-frequency vibrating screen.

[0045] In this invention, secondary powder selection is performed on the output material with a particle size <0.6mm after screening of the finished product to select sand material with a particle size <0.15mm. The primary and secondary powder selections fully ensure that sand material with a particle size <0.15mm is selected. Finally, a targeted tertiary powder selection is performed to store the output material with a particle size <0.075mm in the stone powder silo 8.

[0046] In this invention, the high-frequency vibrating screen, used as a finished product screen, is an existing device and can be purchased directly from the market. Similarly, the vertical roller mill sand making machine 1, the primary air classifier, the secondary air classifier, and the tertiary air classifier are all existing technologies, and each piece of equipment can be purchased directly from the market. During on-site setup, the arrangement can be based on requirements, ensuring that the production process of the special manufactured sand is not disturbed. Furthermore, each piece of equipment in this invention is equipped with a corresponding conveyor belt, ensuring that materials from different equipment can pass through the conveyor belt and the corresponding elevator into the corresponding equipment, thereby better completing the production process of the special manufactured sand.

[0047] In this invention, the vertical roller mill sand making machine 1 is preferably a TRMA series vertical roller mill sand making machine, with a single-unit sand making capacity of up to 1500 tons / hour. It can be used for materials with different hardnesses. The vertical roller mill sand making machine 1 has a small footprint and a simple process flow.

[0048] In this invention, special manufactured sand that meets various gradation requirements can be prepared through the bottom weighing system of three special sand finished product warehouses, and then mixed and shipped from the special sand mixing warehouse.

[0049] Example 2:

[0050] Based on Embodiment 1, in this embodiment, preferably, the primary powder classifier includes at least a composite powder classifier 2 and a dust collector 3. The material crushed from the vertical roller mill sand making machine 1 enters the composite powder classifier 2 via a corresponding conveyor belt and elevator. The output material with a particle size >10mm is transferred back to the vertical roller mill sand making machine 1 via the corresponding conveyor belt and elevator for circulating sand making. The gas carrying the material enters the dust collector 3, which separates the material and gas. The output material with a particle size <0.15mm enters the tertiary powder classifier. The remaining output material with a particle size of 0.15mm-10mm enters the high-frequency vibrating screen 4 for screening.

[0051] Preferably, the dust collector 3 is a double-row cyclone dust collector.

[0052] Preferably, the secondary air classifier includes at least a composite air classifier 25 and a dust collector 26. After passing through the high-frequency vibrating screen 4, the output material with a particle size <0.6mm enters the composite air classifier 25, and the output material with a particle size of 0.15mm-0.6mm is stored in the special sand finished product warehouse 210. After passing through the dust collector 26, the output material with a particle size <0.15mm enters the tertiary air classifier through the corresponding conveyor belt and elevator.

[0053] In this invention, the composite air classifier is a device that combines a V-type air classifier and a dynamic air classifier into one unit, featuring a compact structure, multi-functionality, high efficiency, and energy saving. The V-type air classifier is a static grading and dispersing device, while the dynamic air classifier is a dynamic fine grading and sorting device. The working principle of the composite air classifier is as follows: Material is fed into the V-type air classifier through the inlet. Under the action of several guide plates, impact plates, and the incoming airflow, it is fully dispersed and graded. Relatively coarse particles are discharged from the bottom of the V-type air classifier, while medium-coarse and relatively fine particles enter the dynamic air classifier with the air. They are then further graded by a grid with fixed guide vanes and a rotor. Medium-coarse particles are discharged from the outlet of the dynamic air classifier, and fine particles are discharged from the air outlet of the dynamic air classifier.

[0054] In this invention, dust collector 3 and dust collector 6 have the same structure and function, both adopting a double-row cyclone dust collector to effectively separate the material and air from the material-laden air coming out of the compound air classifier.

[0055] Preferably, the three-stage air classifier is an internal circulation air classifier 7.

[0056] In this invention, the internal circulation air classifier 7 is a mature existing technology that can be purchased directly from the market and then used after being debugged and qualified.

[0057] Preferably, there are multiple high-frequency vibrating screens 4.

[0058] In this invention, the number of high-frequency vibrating screens 4 can be increased or decreased according to requirements. Preferably, four are used. The high-frequency vibrating screens 4 are used in this invention because they are suitable for classifying small particulate materials, capable of screening materials with a particle size of 0.5mm-40mm, and have the advantages of simple structure, screen that is not easily clogged, and high screening efficiency.

[0059] In this invention, the preferred high-frequency vibrating screen 4 is a V-series hydraulic high-frequency screen, suitable for dry screening of manufactured sand or other fine materials. During operation, relatively large coarse materials are bounced higher, while relatively small fine materials are brought closer to the screen, resulting in more screening opportunities. The screen of the high-frequency vibrating screen 4 is driven by a continuously variable speed (0-4200 RPM) hydraulic vibrator, with 5 adjustable amplitude levels, achieving optimal screening efficiency. The screen rotation tensioning system of the high-frequency vibrating screen 4 eliminates the need for additional tools when changing the screen, making operation convenient and quick.

[0060] Preferably, in step three, the two outlets at the lower end of the special sand mixing silo are respectively equipped with an electric sector valve 15 and a humidifying mixer 16.

[0061] Preferably, in step three, the materials in the special sand mixing silo are shipped out by the automatic loading machine 17.

[0062] In this invention, the automatic loading machine 17 is a mature existing device, and its structure and working principle will not be further described here. In this invention, when humidification is not required, the electric sector valve 15 is opened, and the mixed material in the special sand mixing silo is transported to the required location via the automatic loading machine 17. If wet material is required, the mixed material in the special sand mixing silo is humidified by the humidifying mixer 16 before being transported to the required location by the automatic loading machine 17.

[0063] Preferably, the vertical roller mill sand making machine 1, the primary powder classifier, the high-frequency vibrating screen 4, the secondary powder classifier, the tertiary powder classifier, the three special sand finished product warehouses, the special sand mixing warehouse and the stone powder warehouse 8 are all equipped with dust collectors, and the dust collectors are all connected to the stone powder warehouse 8. The lower end of the stone powder warehouse 8 is equipped with a stone powder bulk loading machine 13.

[0064] The present invention provides a simple and efficient production process for special manufactured sand, which not only effectively ensures the quality of the special manufactured sand products, but also allows for independent adjustment of the gradation according to the needs of sand use, effectively reducing the energy consumption and economic cost of special manufactured sand production.

[0065] Preferably, the special sand finished product warehouse 19, special sand finished product warehouse 20 and special sand finished product warehouse 31 respectively store sand with particle sizes of 0.6mm-2.36mm, 0.15mm-0.6mm and 0.075mm-0.15mm.

[0066] In this invention, such as Figure 1 As shown, the process flow combining finished product screening and three-stage air separation effectively ensures the product quality of special manufactured sand and lays the foundation for adjustable gradation of special manufactured sand. After the material from the vertical roller mill sand making machine is discharged, it undergoes primary air separation. After selecting sand with a particle size <0.15mm, it is screened as finished product, reducing the screening load on the high-frequency vibrating screen 4, minimizing screen hole clogging, and improving the screening efficiency of the high-frequency vibrating screen 4. Next, secondary air separation is performed on the discharged material with a particle size <0.6mm after finished product screening, again selecting sand with a particle size <0.15mm. The primary and secondary air separations ensure that sand with a particle size <0.15mm is selected. Finally, a targeted tertiary air separation is performed, storing the discharged material with a particle size <0.075mm in the stone powder silo 10.

[0067] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0068] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0069] The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. All designs that are the same as or similar to the present invention fall within the scope of protection of the present invention. Device structures and method steps not described in detail in this invention are prior art and will not be further described in this invention.

Claims

1. A special manufactured sand production process, characterized in that: The specific steps are as follows: Step 1, fine crushing: from the special sand intermediate material silo, the material with a particle size of 4.75-20mm is transported to the vertical roller mill sand making machine (1) for crushing. The crushed material enters the primary powder classifier. Step 2: Finished product screening and powder selection. After the material passes through the primary powder selection equipment, the output with a particle size >10mm is returned to the vertical roller mill sand making machine (1) for circulating crushing, the output with a particle size <0.15mm enters the tertiary powder selection equipment, and the remaining output with a particle size of 0.15mm-10mm enters the high-frequency vibrating screen (4). The primary powder selection equipment includes at least a composite powder selector (2) and a dust collector (3). The material after being crushed from the vertical roller mill sand making machine (1) enters the composite powder selector (2) through the corresponding conveyor belt and elevator. The output with a particle size >10mm is transferred through the corresponding conveyor belt and elevator and returned to the vertical roller mill sand making machine (1) for circulating sand making. The gas carrying the material enters the dust collector (3), and the dust collector (3) separates the material and gas. The output with a particle size <0.15mm enters the tertiary powder selection equipment, and the remaining output with a particle size of 0.15mm-10mm enters the high-frequency vibrating screen (4) for screening. After passing through the high-frequency vibrating screen (4), the material is divided into three types of discharge: >2.36mm, 0.6mm-2.36mm and <0.6mm. Among them, the discharge with a particle size of >2.36mm is returned to the vertical roller mill sand making machine (1) for recycling and crushing; the sand with a particle size of 0.6mm-2.36mm is stored in the special sand finished product warehouse (9); and the aggregate with a particle size of <0.6mm is sent to the secondary powder classifier. After passing through the secondary classifier, the material with a particle size >0.15mm enters the special sand finished product warehouse 2 (10) for storage; the material with a particle size <0.15mm enters the tertiary classifier; the secondary classifier includes at least a composite classifier 2 (5) and a dust collector 2 (6). After passing through the high-frequency vibrating screen (4), the material with a particle size <0.6mm enters the composite classifier 2 (5), and the material with a particle size of 0.15mm-0.6mm is stored in the special sand finished product warehouse 2 (10). After passing through the dust collector 2, the material with a particle size <0.15mm enters the tertiary classifier through the corresponding conveyor belt and elevator. After passing through the three-stage powder classifier, the material with a particle size >0.075mm is discharged into the special sand finished product warehouse 3 (11) for storage; the material with a particle size <0.075mm is discharged into the stone powder warehouse (8) for storage. Step 3: Special sand mixing and shipping. The output of the three special sand finished product warehouses is weighed by the weighing system corresponding to the bottom of the three warehouses to prepare special manufactured sand that meets various gradation requirements. The special sand is then mixed and shipped from the special sand mixing warehouse.

2. The special manufactured sand production process according to claim 1, characterized in that: Dust collector 1 (3) is a double-row cyclone dust collector.

3. The special manufactured sand production process according to claim 1, characterized in that: The three-stage air classifier is an internal circulation air classifier.

4. The special manufactured sand production process according to claim 1, characterized in that: The high-frequency vibrating screen (4) is multiple.

5. The special manufactured sand production process according to claim 1, characterized in that: In step three, the two outlets at the lower end of the special sand mixing silo are respectively equipped with an electric sector valve (15) and a humidifying mixer (16).

6. The special manufactured sand production process according to claim 1, characterized in that: In step three, the materials in the special sand mixing silo are shipped out by an automatic loading machine (17).

7. The special manufactured sand production process according to claim 1, characterized in that: The vertical roller mill sand making machine (1), primary powder classifier, high frequency vibrating screen (4), secondary powder classifier, tertiary powder classifier, three special sand finished product warehouses, special sand mixing warehouse and stone powder warehouse (8) are all equipped with dust collectors. The dust collectors are all connected to the stone powder warehouse (8). The lower end of the stone powder warehouse (8) is equipped with a stone powder bulk loading machine (13).

Images