A short-process, low-energy consumption system and method for preparing high-quality sandstone aggregate from hard rock

Abstract

The invention discloses a short-process low-energy consumption system process for preparing high-quality sand and gravel aggregate from hard rock, and a method for using the system and the method. The system mainly comprises three units: ore pre-crushing, soil removal and wet sand making, and fine aggregate preparation. The pre-crushing unit comprises hard rock coarse crushing, pre-screening, and medium crushing. The coarse crushing of hard rock can select a gyratory crusher or a jaw crusher according to the production scale. The soil removal and wet sand making unit comprises a high-frequency vibration soil removal screen, a grinding sand making machine, a vibrating screen, a machine-made sand washing system, a sewage treatment system, etc. The fine aggregate preparation unit comprises a grinding sand and gravel machine, a coarse aggregate screen, a machine-made sand screen, conveying equipment, and a machine-made sand powder amount adjustment system, etc., which solves the shortcomings of the current complex production process, low output of a single device, inflexible production control, poor product quality, and high equipment maintenance costs.

Description

Technical Field

[0001] The present invention relates to the technical field of low-energy consumption systems for preparing hard rock, and in particular to a short-process low-energy consumption system and method for preparing high-quality sandstone aggregates from hard rock. Background Art

[0002] Newly built aggregate production lines are developing in the direction of scale, environmental protection and intelligence. However, due to the limitation of insufficient processing capacity of a single device, large-scale aggregate production lines all adopt multi-stage crushing, multiple screening machines and multiple sand making machines in series. Belt conveyors are used to transport materials in each link. There are many belt conveyors, belt conveyor corridors and turning platforms, which leads to an increase in dust and leakage points. Corresponding dust collection equipment and job cleaners are needed. Although the environmental protection problem is solved, the process is too complicated and the production efficiency and economic benefits are reduced.

[0003] In the traditional hard rock (≥120MPa) sand and gravel aggregate production line, the principle of multi-stage high-speed extrusion crushing is used, and coarse, medium and fine multi-stage crushing, screening, conveying and dust removal equipment are integrated. Although the feasibility and quality issues of hard rock aggregate preparation are met, and the whole production process is green and environmentally friendly, the process is complicated, the land occupation and investment are large, the equipment failure rate is high, and there are also problems such as poor quality of machine-made sand and difficult production management: some production lines directly produce multiple aggregate products such as 5-10, 10-20 and 20-31.5mm and directly put them into storage for sale. The market demand for 5-10 and 20-31.5mm products is small, and it is easy to be full of storage to restrict production. The feed particle size of conventional sand making machines for producing machine-made sand is generally controlled below 10mm. The efficiency of directly producing machine-made sand with 20-31.5mm aggregate is low, and it is difficult to return it to the crushing workshop, and the cost is high.

[0004] Conventional equipment configuration or process flow design has poor applicability to ores. For example, when thin-layer rock is used to produce aggregates, the product quality is low, which is manifested in the coarse aggregate and machine-made sand that are not round enough, with a high content of needles and flakes. The prepared concrete has poor workability, which increases production costs. Secondly, the crusher has low efficiency in crushing fine particles (<10mm) and only plays a shaping role. The grading of the machine-made sand produced is unreasonable, with a large fineness modulus and a large amount of stone powder. It not only cannot meet the sand requirements of commercial concrete, but also cannot meet the higher standard requirements for premixed mortar sand, resulting in poor economic benefits.

[0005] Although dry sand making can solve the problem of high stone powder content in aggregates, the large amount of dust generated during the production process causes serious environmental pollution. For wet sand making, the output of finished sand is low, and a large volume silo needs to be set up for dehydration. The dehydration cycle is long, the stone powder loss is large, and it is difficult to recover and reuse the mud cake. The stone powder content of the finished sand is low, the grading is unreasonable, and the production wastewater pollutes the environment greatly. The water treatment cost is high, and it is difficult to achieve resource recycling. Some production lines have rough and backward production processes, low automation levels, and no intelligence, resulting in uncontrollable product output, uneven production, high energy consumption, and low efficiency. Summary of the invention

[0006] In response to the above technical problems, the present invention provides a short-process, low-energy consumption system and method for preparing high-quality sand and gravel aggregates from hard rock, which solves the current shortcomings of complex production process, low output of a single device, inflexible production control, poor product quality, and high equipment maintenance costs.

[0007] The technical solution provided by the present invention is as follows:

[0008] A short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock, characterized in that it comprises an ore pre-crushing unit, a soil removal and wet sand making unit and a fine aggregate preparation unit, wherein the ore pre-crushing unit is connected to the soil removal and wet sand making unit and the fine aggregate preparation unit respectively.

[0009] The ore pre-crushing unit comprises a hard rock coarse crushing device, a plate feeder, a pre-screening device, and a medium crushing device. The discharge port of the hard rock coarse crushing device is connected to the plate feeder, and the plate feeder is connected to the feed port of the pre-screening device through a conveying component. The pre-screening device is provided with a first outlet, a second outlet, and a third outlet. The first outlet of the pre-screening device is connected to the feed port of the medium crushing device, and the second outlet of the pre-screening device is connected to the fine aggregate preparation unit through a conveyor belt. The third outlet of the pre-screening device is connected to the wet sand making unit through a conveyor belt and soil removal, and the discharge port of the medium crushing device is connected to the conveyor belt connected to the second outlet of the screening device.

[0010] The soil removal and wet sand making unit comprises a high-frequency soil removal screen, a grinding sand making machine, a vibrating screen, a machine-made sand washing mechanism, and a water treatment mechanism. The first outlet on the high-frequency soil removal screen is connected to the grinding sand making machine, and the second outlet arranged on the bottom of the high-frequency soil removal screen is connected to the abandoned soil pile shed through a transmission belt. The discharge port of the grinding sand making machine is connected to the vibrating screen through a transmission belt, and the vibrating screen is connected to the machine-made sand washing mechanism, and the machine-made sand washing mechanism is connected to the water treatment mechanism.

[0011] The fine aggregate preparation unit comprises an intermediate stockpile, a metering scale, a sand and stone grinding machine, a coarse aggregate screening device, a machine-made sand screening device, and a machine-made sand powder content regulating mechanism. The intermediate stockpile is sequentially connected to the metering scale, the sand and stone grinding machine, the coarse aggregate screening device, the machine-made sand screening device, and the machine-made sand powder content regulating mechanism through a conveying device. The raw material conveying assembly and the circulating material conveying assembly below the intermediate stockpile are connected to the sand and stone grinding machine. The discharge port of the sand and stone grinding machine is connected to the coarse aggregate screening device. The under-screen outlet of the coarse aggregate screening device is connected to the upper-screen inlet of the machine-made sand screening device. The bottom discharge port of the machine-made sand screening device is connected to the inlet of the machine-made sand powder content regulating mechanism through a conveying device.

[0012] The machine-made sand powder content regulating mechanism is composed of a combined powder classifier, a cyclone dust collector, a circulating fan, a tail bag dust collector and a tail exhaust fan. The upper air outlet of the combined powder classifier is connected to the cyclone dust collector and the tail bag dust collector respectively. A circulating fan is arranged between the combined powder classifier and the cyclone dust collector and the tail bag dust collector. The tail bag dust collector is connected to the tail exhaust fan.

[0013] Specifically, the discharge port of the combined powder classifier is connected to the finished sand warehouse through the finished sand conveying equipment, and the discharge ports of the cyclone dust collector and the tail bag dust collector are connected to the stone powder warehouse through the stone powder conveying equipment.

[0014] Specifically, the combined powder classifier consists of a static powder classifier and a dynamic powder classifier.

[0015] Specifically, the coarse aggregate screening equipment is provided with a first outlet, a second outlet, a third outlet and a fourth outlet under the screen, the first outlet of the coarse aggregate screening equipment is connected to the grinding sand and stone machine through a circulating material conveying belt conveyor, the second outlet of the coarse bone screening equipment is connected to the grinding sand and stone machine through a circulating material conveying belt conveyor, the second outlet of the coarse bone screening equipment is connected to the finished product warehouse or finished product warehouse through an aggregate finished product conveying belt conveyor, the third outlet of the coarse aggregate screening equipment is connected to the finished product warehouse through an aggregate finished product conveying belt conveyor, and the fourth outlet of the coarse bone screening equipment is connected to the inlet above the screen of the machine-made sand screening equipment through a slide pipe. The machine-made sand screening equipment is provided with a fifth outlet, a sixth outlet and a seventh outlet under the screen. The fifth outlet of the machine-made sand screening equipment is connected to the grinding sand and gravel machine through a circulating material conveying belt conveyor, the fifth outlet of the machine-made sand screening equipment is connected to the finished product warehouse through an aggregate finished product conveying belt conveyor, the sixth outlet of the machine-made sand screening equipment is connected to the grinding sand and gravel machine through a circulating material conveying belt conveyor, the sixth outlet of the machine-made sand screening equipment is connected to the inlet of the machine-made sand powder amount regulating mechanism through the machine-made sand semi-finished product conveying belt conveyor, and two products, finished machine-made sand and fine powder, are obtained through the machine-made sand powder content regulating mechanism. The seventh outlet of the machine-made sand screening equipment is connected to the finished product warehouse through a finished product conveying belt conveyor.

[0016] Specifically, the hard rock coarse crushing equipment is one of the following: a gyratory crusher, a jaw crusher, and the corresponding machine is selected according to the scale.

[0017] Specifically, the secondary crushing equipment adopts an inertial cone crusher.

[0018] Specifically, the conveying equipment is one of the following: a belt conveyor, a bucket elevator.

[0019] Specifically, the number of discharge ports provided on the sand and gravel grinding machine is ≥1, each coarse material port of the sand and gravel grinding machine is connected to a coarse aggregate screening device, the number of coarse aggregate screening devices is consistent with the number of discharge ports of the sand and gravel grinding machine, and each discharge port is connected to a group of coarse aggregate screening devices.

[0020] Specifically, the grinding sand and stone machine is only a device that meets the needs of crushing and shaping coarse aggregate and machine-made sand. A feed port is designed on the upper part, and 1 or 2 discharge ports are designed on the lower part. The material quantity and grading of each discharge port are very small. The crushing and shaping are highly adaptable to the feed particle size and hardness. Hard rock of 0-80mm can be directly fed. There are pre-grading devices and discharge devices inside the equipment to control the discharge particle size to 90% <40mm.

[0021] Specifically, the number of screen layers and aperture of the coarse aggregate screening equipment can be adjusted according to product requirements, and the output of aggregate can be flexibly adjusted by adjusting the valve opening of the discharge port.

[0022] Specifically, the vibrating screen is provided with a first outlet, a second outlet and a third outlet. The first outlet of the vibrating screen is connected to the feed port of the grinding sand making machine through a circulating material conveying belt conveyor. The second outlet of the vibrating screen is connected to the grinding sand making machine through a circulating material conveying belt conveyor after connecting a three-way valve. The second outlet of the vibrating screen is connected to the machine-made sand water washing mechanism through a machine-made sand semi-finished product conveying belt conveyor. The third outlet of the vibrating screen is connected to the machine-made sand water machine mechanism through a machine-made sand semi-finished product conveying belt conveyor.

[0023] A short-process and low-energy method for preparing high-quality sandstone aggregate from hard rock, the specific steps of which are as follows:

[0024] 1. The raw ore is directly fed into the hard rock coarse crushing equipment after transportation. After the hard rock coarse crushing equipment, it is divided into three particle sizes of -20mm, 20-80mm and 80+mm by the pre-screening equipment. The -20mm soil-containing material is transported to the soil removal and wet sand making unit, and the 80+mm is sent to the medium crushing equipment. After the medium crushing equipment, the -80mm material and the 20-80mm material are sent to the middle pile shed of the fine aggregate preparation unit together;

[0025] 2. After the pre-screening equipment, the -20mm soil-containing raw materials are conveyed to the feed port of the high-frequency soil removal screen. The -5mm slag under the screen is directly conveyed to the slag pile shed, and the 5+mm ore on the screen is conveyed to the feed port of the grinding sand making machine. After the grinding sand making machine crushes and shapes the ore, the material is discharged from the discharge port below it and conveyed to the feed port of the vibrating screen through a belt conveyor. The vibrating screen washes and screens the material. The machine-made sand semi-finished products output from the second and third outlets on the vibrating screen are conveyed to the machine-made sand washing mechanism. The sewage generated by sand washing and the required clean water are met by the water treatment mechanism. The fineness modulus of the machine-made sand can be flexibly adjusted by adjusting the valve opening of the second outlet of the vibrating screen;

[0026] 3. The raw materials in the middle pile are fed into the grinding sand and stone machine after metering and taking. The grinding sand and stone machine crushes and shapes the materials and then discharges them from its lower discharge port. The grinding sand and stone machine can effectively control the particle size of the discharge material, and then it is sent to the coarse aggregate screening equipment for classification through the conveying equipment. The large particles screened out by the top screen on the coarse aggregate screening equipment are directly discharged to the circulating material conveyor belt conveyor and returned to the grinding sand and stone machine to continue to produce aggregates. The particles screened out by the second layer of mesh screen on the coarse aggregate screening equipment are 20-31.5mm aggregates, which can be discharged to the aggregate finished product conveyor belt conveyor and then transported to the finished product warehouse. , or it can be discharged to the circulating material conveyor belt conveyor and returned to the grinding sand and gravel machine to continue to prepare smaller specifications of sand and gravel aggregates. The particles screened out by the third screen on the coarse aggregate screening equipment are 10-20mm aggregates. This product is the most popular in the market and is directly discharged to the finished product conveyor belt conveyor and directly sent to the warehouse. The -10mm fine material screened out from the bottom layer of the coarse aggregate screening equipment is delivered to the upper screen entrance of the machine-made sand screening equipment through the chute. The number of screen layers and aperture of the coarse aggregate screening equipment can be adjusted according to product requirements, and the output of aggregates can be flexibly adjusted by adjusting the valve opening of the discharge port.

[0027] The machine-made sand grading screen has two layers of screens, which divide the material into three particle sizes: 5-10mm, 2.5-5mm and <2.5mm. The 5-10mm aggregate on the upper screen can be discharged to the finished product conveyor belt conveyor for direct storage, or discharged to the circulating material conveyor belt and returned to the grinding sand and stone machine to continue to produce machine-made sand. The -2.5mm fine particles under the lower screen are directly stored as finished machine-made sand. The 2.5-4.75mm coarse particles between the two layers of screens can be mixed with the -2.5mm finished product at the bottom of the lower screen according to the proportion to adjust the machine-made sand fineness modulus, and then sent to the machine-made sand powder content adjustment mechanism through the machine-made sand semi-finished product conveyor belt conveyor to adjust the powder content. They can also be discharged to the circulating material conveyor belt and returned to the grinding sand and stone machine to continue to prepare machine-made sand.

[0028] The semi-finished machine-made sand is fed into the combined powder classifier with the machine-made sand powder content adjustment mechanism. By adjusting the speed of the circulating fan and the rotation frequency of the dynamic powder classifier in the combined powder classifier and other parameters, the powder content of the machine-made sand can be flexibly controlled, and the fineness of the associated fine powder can be controlled. The machine-made sand product is discharged from the discharge port at the bottom of the combined powder classifier and transported to the machine-made sand finished product warehouse through the finished product conveying equipment. The stone powder enters the cyclone dust collector together with the air from the upper air outlet of the combined powder classifier. Most of the stone powder is collected by the cyclone dust collector and discharged from its lower unloading port. The small amount of fine powder not captured by the cyclone dust collector is captured by the downstream tail bag dust collector. The two streams of stone powder captured by the cyclone dust collector and the tail bag dust collector are sent to the stone powder bin through the stone powder conveying equipment.

[0029] Specifically, in step 3, 20-31.5 mm, 10-20 mm and 5-10 mm aggregates, as well as 0-5 mm ordinary sand or 0-2.5 mm fine sand for premixed mortar are screened out through coarse aggregate screening equipment and machine-made sand screening equipment. Single-grained aggregates such as 16-31.5 mm, 16-25 mm, 10-16 mm or other continuously graded aggregates are produced by adjusting the aperture of the screen. According to the sales situation of various aggregates and machine-made sand, the valve of the screen discharge port is adjusted in time to discharge the excess product onto the circulating material conveying equipment, and return to the grinding sand and stone machine to continue to produce products.

[0030] Beneficial effects of the present invention:

[0031] The present invention

[0032] The system designed by the present invention mainly includes three units: ore pre-crushing unit, soil removal and wet sand making unit, and fine aggregate preparation unit, which solves the shortcomings of the current complex production process, low output of a single device, inflexible production control, poor product quality, and high equipment maintenance costs. A single grinding sand and gravel machine can produce sand and gravel aggregates to meet the output of 300-2500t / h. If only machine-made sand products are produced, the output can reach 200-1500t / h. The life of the equipment wear-resistant parts in processing siliceous hard rock ores can reach 1500-2500h. The hourly output and the life of the wear-resistant parts are more than 10 times that of conventional sand making machines.

[0033] The present invention changes the process layout of traditional crushing and screening equipment, reduces the number of crushing equipment and the number and length of belt conveyors, simplifies the production line, reduces the investment in related equipment and the cost of later maintenance. By adopting the present invention, the gradation of sand and gravel aggregate produced is continuously adjustable, and the output of sand and gravel aggregate can be fully adjusted, meeting the market demand for different products and avoiding the embarrassment of being unable to produce due to full warehouses; the shaping effect of the grinding sand and gravel machine is very good, which improves the quality of sand and gravel aggregate; the screening unit can flexibly adjust the output of each coarse aggregate product and the fineness modulus of machine-made sand; the production process control is intelligent, green and environmentally friendly, and the controllability and flexibility of the entire production process are guaranteed;

[0034] The combined powder selector used in the artificial sand powder content regulating mechanism of the present invention has high powder removal efficiency, the powder (200 mesh) content of artificial sand can be flexibly adjusted within the range of 0-10%, and the specific surface area of ​​stone powder can reach more than 400m2 / kg. The high-quality artificial sand produced by this system can be used in high-value fields such as high-performance concrete, premixed mortar, UHPC mortar and tile adhesive aggregate, and the stone powder can be used as concrete admixture or cement admixture, etc., which greatly improves product competitiveness and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the entire system of a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock according to the present invention;

[0036] Figure 2 A schematic diagram of an ore pre-crushing unit of a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock according to the present invention;

[0037] Figure 3 A schematic diagram of a soil removal and wet sand making unit of a short-process, low-energy consumption system for preparing high-quality sand and gravel aggregate from hard rock according to the present invention;

[0038] Figure 4 A schematic diagram of a fine aggregate preparation unit of a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock according to the present invention;

[0039] Figure 5 A schematic diagram of a machine-made sand powder quantity adjustment mechanism of a short-process, low-energy consumption system for preparing high-quality sand and gravel aggregate from hard rock according to the present invention;

[0040] As shown in the figure: A. Ore pre-crushing unit, B. Soil removal and wet sand making unit, C. Fine aggregate preparation unit, 1. Hard rock coarse crushing equipment, 2. Plate feeder, 3. Pre-screening equipment, 4. Medium crushing equipment, 5. High-frequency soil removal screen, 50. Abandoned soil pile shed, 6. Grinding sand making machine, 7. Vibrating screen, 8. Machine-made sand washing mechanism, 81. Water-washed sand, 9. Water treatment mechanism, 91. Sewage treatment, 92. Clear water tank, 10. Intermediate pile shed, 11. Measuring and material taking scale, 13. Grinding sand and stone machine, 14, coarse aggregate screening equipment, 15. Machine-made sand screening equipment, 16. Machine-made sand powder content adjustment mechanism, 161. Combined powder selector, 162. Cyclone dust collector, 163. Circulating fan, 164. Tail bag dust collector, 165. Tail exhaust fan, 166. Stone powder conveying equipment, 167. Finished sand conveying equipment. DETAILED DESCRIPTION

[0041] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0043] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] Example 1

[0045] like Figure 1 A short-process, low-energy consumption system for preparing high-quality sand and gravel aggregate from hard rock includes an ore pre-crushing unit A, a soil removal and wet sand making unit B, and a fine aggregate preparation unit C. Figure 2 The ore pre-crushing unit A includes hard rock coarse crushing equipment 1, plate feeder 1, pre-screening equipment 3, medium crushing equipment 4 and supporting auxiliary equipment, etc. The supporting auxiliary equipment refers to the conveyor belt conveyor or bucket elevator. The hard rock coarse crushing equipment can select a gyratory crusher or a jaw crusher according to the scale, and the medium crushing equipment adopts an inertial cone crusher.

[0046] The raw ore is directly fed into the feed port of the hard rock coarse crushing equipment 1, the discharge port of the hard rock coarse crushing equipment 1 is connected with the plate feeder 2, the plate feeder 2 is connected with the upper feed port of the pre-screening equipment 3 through the conveying equipment, the pre-screening equipment 3 is provided with a first outlet, a second outlet and a third outlet on the bottom under the screen, the first outlet is connected with the feed port of the medium crushing equipment 4, the second outlet is connected with the middle stockpile 10 in the fine aggregate preparation unit C through the conveyor belt, the third outlet is connected with the high-frequency soil removal screen 5 of the soil removal and wet sand making unit C through the conveyor belt conveyor, and the discharge port of the medium crushing equipment 4 is connected with the conveyor belt conveyor behind the second outlet of the pre-screening equipment.

[0047] like Figure 2The soil removal and wet sand making unit C comprises a high-frequency soil removal screen 5, a grinding sand making machine 6, a vibrating screen 7, a machine-made sand washing mechanism, a water treatment system 9, etc. The first outlet on the high-frequency soil removal screen 5 is connected to the grinding sand making machine 6, and the second outlet arranged on the bottom of the high-frequency soil removal screen 5 is connected to the abandoned soil pile 50 through a transmission belt conveyor. The discharge port of the grinding sand making machine 6 is connected to the vibrating screen 7 through a transmission belt conveyor. The vibrating screen 7 washes and screens the material. The vibrating screen has two layers of screens, which are correspondingly provided with a first outlet, a second outlet and a third outlet at the bottom. The first outlet is connected to the circulating material conveying belt and then sent to the grinding sand making machine 6. The second outlet is connected to the circulating material conveying belt conveyor through a three-way valve and sent to the grinding sand making machine 6 and connected to the machine-made sand semi-finished product conveying belt conveyor to send to the machine-made sand washing mechanism 8. The third outlet is connected to the machine-made sand semi-finished product conveying belt conveyor and sent to the machine-made sand washing mechanism 8. The machine-made sand washing mechanism 8 is connected to the water treatment mechanism 9. The machine-made sand under the screen is transported to the sand washing machine, and the mud powder can be washed away to obtain the machine-made sand product.

[0048] like Figure 3The fine aggregate preparation unit C includes an original intermediate stockpile 10, a weighing scale 11, a conveying device 12, a grinding sand and stone machine 13, a coarse aggregate screening device 14, a machine-made sand screening device 15, a machine-made sand powder content regulating mechanism 16, a sand and gravel finished product warehouse, and a stone powder warehouse. The intermediate stockpile 10, the weighing scale 11, the grinding sand and stone machine 13, the coarse aggregate screening device 14, the machine-made sand screening device 15, the machine-made sand powder content regulating mechanism 16, and the sand and gravel finished product warehouse and the stone powder warehouse are connected in sequence through the conveying equipment, wherein the conveying equipment includes a belt conveyor or a bucket elevator The upper inlet of the sand and gravel grinding machine 13 is connected to the raw material conveying system and the circulating material conveying system below the middle pile shed 10. One to two discharge ports are designed below the sand and gravel grinding machine 13. The number of the coarse aggregate screening equipment 14 is consistent with the number of the discharge ports below the sand and gravel grinding machine 13. Each discharge port is connected to a group of coarse aggregate screening equipment 14. The discharge port of the sand and gravel grinding machine is connected to the upper screen inlet of the coarse aggregate screening equipment 14 through the conveying equipment. The lower screen outlet of the coarse aggregate screening equipment 14 is connected to the upper screen inlet of the machine-made sand screening equipment 15. The lower screen outlet of the machine-made sand screening equipment 15 is connected to the semi-automatic sand screening equipment 15. Finished machine-made sand conveying system, the coarse aggregate screening device 14 is provided with a first outlet, a second outlet, a third outlet and a fourth outlet at the bottom under the screen, the first outlet is connected to the circulating material conveying belt conveyor to send back to the grinding sand and gravel machine 13, the second outlet is connected to the circulating material conveying belt conveyor to send into the grinding sand and gravel machine 13 and connected to the finished aggregate conveying belt conveyor to send to the finished sand and gravel warehouse, the third outlet is connected to the finished aggregate conveying belt conveyor to send to the finished sand and gravel warehouse, the fourth outlet at the bottom is connected to the screen inlet of the machine-made sand screening device 15 through a chute, the machine-made sand screening device 15 has two layers of screens,, machine-made sand The screening equipment 15 is provided with a fifth outlet, a sixth outlet and a seventh outlet at the bottom under the screen. The fifth outlet is connected to the circulating material conveying belt conveyor to send it to the grinding sand and gravel machine 13 and is connected to the aggregate finished product conveying belt conveyor to send it to the sand and gravel finished product warehouse. The sixth outlet is connected to the circulating material conveying belt through a three-way valve to send it back to the grinding sand and gravel machine 13 and is connected to the machine-made sand semi-finished product conveying belt conveyor to send it to the machine-made sand powder amount regulating mechanism 16. The seventh outlet is connected to the machine-made sand semi-finished product conveying belt conveyor to send it to the machine-made sand powder amount regulating mechanism 16, and the two products of finished machine-made sand and fine powder are obtained by the machine-made sand powder content regulating mechanism 16. Among them, the grinding sand and stone machine 13 is only a crushing and shaping equipment that can meet the needs of coarse aggregate and machine-made sand. A feed port is designed on the upper part, and 1 or 2 discharge ports are designed on the lower part. The material quantity and grading of each discharge port are very small. The crushing and shaping are highly adaptable to the feed particle size and hardness. Hard rock of 0-80mm can be directly fed. There are pre-grading devices and discharge devices inside the equipment to control the discharge particle size to 90% <40mm. The fineness modulus of the machine-made sand can be flexibly adjusted by adjusting the valve opening of the sixth outlet of the machine-made sand screening equipment 15.

[0049] like Figure 4The inlet of the machine-made sand powder content regulating mechanism is connected to the bottom discharge port of the machine-made sand screening equipment 15 through the conveying equipment, and the machine-made sand semi-finished product is fed into the machine-made sand powder content regulating mechanism 16. The machine-made sand powder content regulating mechanism 16 is composed of a combined powder classifier 161 composed of a static powder classifier and a dynamic powder classifier, a cyclone dust collector 142, a circulating fan 163, a tail bag dust collector 164 and a tail exhaust fan 165 and other main equipment. The system works in a fully enclosed negative pressure to meet the ultra-low dust emission. The combined powder classifier completes the powder content adjustment, the cyclone dust collector and the bag dust collector complete the powder capture, and the finished machine-made sand is discharged from the bottom discharge port of the powder classifier. The machine-made sand and stone powder are sent to the finished product warehouse or finished product warehouse through the conveying equipment.

[0050] A short-process and low-energy method for preparing high-quality sandstone aggregate from hard rock, the specific steps are as follows:

[0051] 1. The raw ore is directly fed into the hard rock coarse crushing equipment 1 after transportation. After coarse crushing, it is divided into three particle sizes of -20mm, 20-80mm and 80+mm by the pre-screening equipment 3. The -20mm soil-containing material is transported to the soil removal and wet sand making unit B, and the 80+mm enters the medium crushing equipment 4. After the medium crushing, the -80mm material and the 20-80mm material are sent to the middle pile shed 10 in front of the fine aggregate preparation workshop;

[0052] 2. The -20mm soil-containing raw materials from the ore pre-crushing unit A are fed into the feed port of the high-frequency soil removal screen 5, the -5mm slag under the screen is directly transported to the slag pile 50, and the 5+ ore on the screen is transported to the feed port of the grinding and sand making machine 6. After the grinding and sand making machine 6 crushes and shapes the ore, the material is discharged from the discharge port below it and then transported to the feed port of the vibrating screen 7 through a belt conveyor. The vibrating screen 7 washes and screens the material. The vibrating screen 7 has two layers of screens, correspondingly provided with a first outlet, a second outlet and a third outlet at the bottom. The first outlet is connected to the circulating material conveying belt conveyor, the second outlet is connected to the circulating material conveying belt and the machine-made sand semi-finished product conveying belt conveyor through a three-way valve, and the third outlet is connected to the machine-made sand semi-finished product conveying belt conveyor. The fineness modulus of the machine-made sand can be flexibly adjusted by adjusting the valve opening of the second outlet. The machine-made sand semi-finished product is transported to the machine-made sand washing mechanism 8, and the sewage generated by sand washing and the required clean water are met by the water treatment record 9;

[0053] 3. The raw materials in the middle pile 10 are fed into the grinding sand and stone machine 13 through metering and feeding 11 and conveying. The grinding sand and stone machine 13 crushes and shapes the materials and then discharges them from the lower discharge port. The grinding sand and stone machine 13 can effectively control the particle size of the discharged materials, and then send them to the coarse aggregate screening equipment 14 for classification through the conveying equipment. The coarse aggregate screening equipment 14 consists of 2 or 3 layers of screens. The large particles on the top screen are directly discharged to the circulating material conveyor belt conveyor and return to the grinding sand and stone machine 13 to continue to produce aggregates. The particles on the second screen are 20-31.5mm aggregates, which can be discharged. It can be put into the finished product conveying equipment and directly stored in the warehouse, and can also be discharged to the circulating material conveying belt to return to the grinding sand and gravel machine 13 to continue to prepare smaller sand and gravel aggregates. The particles on the third screen are 10-20mm aggregates. This product is the most popular in the market and is directly discharged to the finished product conveying equipment and directly stored in the warehouse. The -10mm fine material under the bottom screen reaches the screen entrance of the machine-made sand screening equipment 15 through the chute. The number of screen layers and aperture of the coarse aggregate screening equipment 14 can be adjusted according to product requirements, and the output of aggregate can be flexibly adjusted by adjusting the valve opening of the discharge port.

[0054] The machine-made sand screening equipment 15 has two layers of screens, which divide the materials into three particle sizes of 5-10mm, 2.5-5mm and <2.5mm. The 5-10mm aggregate on the upper screen can be discharged to the finished product conveying equipment for direct storage, and can also be discharged to the circulating material conveying belt to return to the grinding sand and gravel machine 13 to continue to produce machine-made sand. The -2.5mm fine particles under the lower screen are directly stored as finished machine-made sand. The 2.5-4.75mm coarse particles between the two layers of screens can be mixed with the -2.5mm finished product on the bottom of the lower screen according to the proportion to adjust the machine-made sand fineness modulus, enter the machine-made sand powder content adjustment mechanism 16 through the conveying equipment to adjust the powder content, and can also be discharged to the circulating material conveying belt to return to the grinding sand and gravel machine 13 to continue to prepare machine-made sand.

[0055] The semi-finished machine-made sand is fed into the combined powder classifier 161 of the machine-made sand powder content regulating mechanism 16. By adjusting the parameters such as the rotating speed of the circulating fan 163 and the rotation frequency of the dynamic powder classifier in the combined powder classifier 161, the powder content of the machine-made sand can be flexibly adjusted, and the fineness of the associated fine powder can be controlled. The machine-made sand product is discharged from the discharge port at the bottom of the combined powder classifier 161 and transported to the machine-made sand finished product warehouse through the finished product conveying equipment. The stone powder enters the cyclone dust collector 162 together with the air from the upper air outlet of the combined powder classifier 161. The cyclone dust collector 162 collects most of the stone powder and discharges it from its lower discharge port. The small amount of fine powder not captured by the cyclone dust collector 162 is captured by the downstream tail bag dust collector 164. The two streams of stone powder captured by the cyclone dust collector 162 and the tail bag dust collector 164 are sent to the stone powder bin through the stone powder conveying equipment.

[0056] Among them, the coarse aggregate screening device 14 and the machine-made sand screening device 15 screen out 20-31.5mm, 10-20mm and 5-10mm aggregates, as well as 0-5mm ordinary sand or 0-2.5mm fine sand for premixed mortar. It is also possible to produce single-grained aggregates or other continuously graded aggregates such as 16-31.5mm, 16-25mm, 10-16mm by adjusting the aperture of the screen. According to the sales situation of various aggregates and machine-made sand, the valve of the screen discharge port is adjusted in time to discharge the excess product to the circulating material conveying equipment, and return to the grinding sand and stone machine (13) to continue to produce best-selling products.

[0057] The combined powder selecting machine equipped with the artificial sand powder content adjustment mechanism 16 has high powder removal efficiency, and the powder 200 mesh content of the artificial sand can be flexibly adjusted within the range of 0-10%, and the specific surface area of ​​the stone powder can reach more than 400m2 / kg. The high-quality artificial sand produced by this system can be used in high-value fields such as high-performance concrete, premixed mortar, UHPC mortar and tile adhesive aggregate, and the stone powder can be used as concrete admixture or cement admixture, etc., which greatly improves the product competitiveness and economic benefits.

[0058] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. The various components mentioned in the present invention are common technologies in the existing field. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only to illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A short-process and low-energy method for preparing high-quality sandstone aggregate from hard rock, the specific steps of which are as follows: Step 1. The raw ore is directly fed into the hard rock coarse crushing equipment after transportation. After the hard rock coarse crushing equipment, it is divided into three particle sizes of 0-20mm, 20-80mm and 80+mm by the pre-screening equipment. The 0-20mm soil-containing material is transported to the soil removal and wet sand making unit, and the 80+mm is sent to the medium crushing equipment. After the medium crushing equipment, the 0-80mm material and the 20-80mm material are sent to the middle pile shed of the fine aggregate preparation unit together; Step 2. The 0-20mm soil-containing raw materials after the pre-screening equipment are conveyed to the feed port of the high-frequency soil removal screen, the 0-5mm slag that is screened out is directly conveyed to the slag pile shed, and the 5+mm ore that is screened out is conveyed to the feed port of the grinding sand making machine. After the grinding sand making machine crushes and shapes the ore, the material is discharged from the discharge port below it and conveyed to the feed port of the vibrating screen through a belt conveyor. The vibrating screen washes and screens the material, and the machine-made sand semi-finished products output from the second outlet and the third outlet on the vibrating screen are conveyed to the machine-made sand washing mechanism. The sewage generated by sand washing and the required clean water are met by the water treatment mechanism, wherein the fineness modulus of the machine-made sand can be flexibly adjusted by adjusting the valve opening of the second outlet of the vibrating screen; Step 3. The raw materials in the middle pile are fed into the grinding sand and stone machine after metering and taking. The grinding sand and stone machine crushes and shapes the materials and then discharges them from its lower discharge port. The grinding sand and stone machine can effectively control the particle size of the discharge material, and then it is sent to the coarse aggregate screening equipment for classification through the conveying equipment. The large particles screened out by the top screen on the coarse aggregate screening equipment are directly discharged to the circulating material conveyor belt conveyor and returned to the grinding sand and stone machine to continue to produce aggregates. The particles screened out by the second layer of mesh screen on the coarse aggregate screening equipment are 20-31.5mm aggregates, which can be discharged to the aggregate finished product conveyor belt conveyor The particles screened out by the third screen on the coarse aggregate screening equipment are 10-20mm aggregates, which are directly discharged to the finished product conveyor belt and sent directly to the storage. The 0-10mm fine materials screened out by the bottom layer of the coarse aggregate screening equipment are sent to the upper screen inlet of the machine-made sand screening equipment through the chute. The number of screen layers and aperture of the coarse aggregate screening equipment are adjusted according to product requirements, and the output of aggregates is flexibly adjusted by adjusting the valve opening of the discharge port. The machine-made sand grading screen has two layers of screens, which divide the material into three particle sizes: 5-10mm, 2.5-5mm and <2.5mm. The 5-10mm aggregate on the upper screen can be discharged to the finished product conveyor belt conveyor for direct storage, and can also be discharged to the circulating material conveyor belt to return to the grinding sand and stone machine to continue to produce machine-made sand. The 0-2.5mm fine particles under the lower screen are directly stored as finished machine-made sand. The 2.5-4.75mm coarse particles between the two layers of screens can be mixed with the 0-2.5mm finished product at the bottom of the lower screen according to the proportion to adjust the machine-made sand fineness modulus, and sent to the machine-made sand powder content adjustment mechanism through the machine-made sand semi-finished product conveyor belt conveyor to adjust the powder content, and can also be discharged to the circulating material conveyor belt to return to the grinding sand and stone machine for further preparation. Machine-made sand and semi-finished machine-made sand are fed into the combined powder classifier with the machine-made sand powder content adjustment mechanism. By adjusting the speed of the circulating fan and the dynamic powder classifier rotation frequency parameters in the combined powder classifier, it can not only flexibly adjust the powder content of the machine-made sand, but also control the fineness of the associated fine powder. The machine-made sand product is discharged from the discharge port at the bottom of the combined powder classifier and transported to the machine-made sand finished product warehouse through the finished product conveying equipment. The stone powder enters the cyclone dust collector together with the air from the upper air outlet of the combined powder classifier. Most of the stone powder is collected by the cyclone dust collector and discharged from its lower unloading port. The small amount of fine powder not captured by the cyclone dust collector is captured by the downstream tail bag dust collector. The two streams of stone powder captured by the cyclone dust collector and the tail bag dust collector are sent to the stone powder bin through the stone powder conveying equipment.

2. According to claim 1, a short-process, low-energy consumption method for preparing high-quality sandstone aggregate from hard rock is prepared using a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock, characterized in that The system comprises an ore pre-crushing unit, a soil removal and wet sand making unit and a fine aggregate preparation unit, wherein the ore pre-crushing unit is respectively connected to the soil removal and wet sand making unit and the fine aggregate preparation unit.

3. The short-process and low-energy consumption method for preparing high-quality sandstone aggregate from hard rock according to claim 2, which is prepared using a short-process and low-energy consumption system for preparing high-quality sandstone aggregate from hard rock, characterized in that The ore pre-crushing unit includes a hard rock coarse crushing device, a plate feeder, a pre-screening device, and a medium crushing device. The discharge port of the hard rock coarse crushing device is connected to the plate feeder, and the plate feeder is connected to the feed port of the pre-screening device through a conveying component. The pre-screening device is provided with a first outlet, a second outlet, and a third outlet. The first outlet of the pre-screening device is connected to the feed port of the medium crushing device, and the second outlet of the pre-screening device is connected to a fine aggregate preparation unit through a conveyor belt. The third outlet of the pre-screening device is connected to a wet sand making unit through a conveyor belt and soil removal, and the discharge port of the medium crushing device is connected to the conveyor belt connected to the second outlet of the screening device.

4. The short-process, low-energy consumption method for preparing high-quality sandstone aggregate from hard rock according to claim 2, which is prepared using a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock, characterized in that The soil removal and wet sand making unit includes a high-frequency soil removal screen, a grinding sand making machine, a vibrating screen, a machine-made sand washing mechanism, and a water treatment mechanism. The first outlet on the high-frequency soil removal screen is connected to the grinding sand making machine, and the second outlet arranged on the bottom of the high-frequency soil removal screen is connected to the abandoned soil pile shed through a transmission belt. The discharge port of the grinding sand making machine is connected to the vibrating screen through a transmission belt, and the vibrating screen is connected to the machine-made sand washing mechanism, and the machine-made sand washing mechanism is connected to the water treatment mechanism.

5. The short-process and low-energy consumption method for preparing high-quality sandstone aggregate from hard rock according to claim 2, which is prepared using a short-process and low-energy consumption system for preparing high-quality sandstone aggregate from hard rock, characterized in that The fine aggregate preparation unit comprises an intermediate stockpile, a metering scale, a sand and gravel grinding machine, a coarse aggregate screening device, an artificial sand screening device, and an artificial sand powder content regulating mechanism. The intermediate stockpile is connected to the metering scale, the sand and gravel grinding machine, the coarse aggregate screening device, the artificial sand screening device, and the artificial sand powder content regulating mechanism in sequence through a conveying device. The raw material conveying assembly and the circulating material conveying assembly below the intermediate stockpile are connected to the sand and gravel grinding machine. The discharge port of the sand and gravel grinding machine is connected to the coarse bone screening device. The under-screen outlet of the coarse aggregate screening device is connected to the upper-screen inlet of the artificial sand screening device. The bottom discharge port of the artificial sand screening device is connected to the inlet of the artificial sand powder content regulating mechanism through a conveying device.

6. The short-process, low-energy consumption method for preparing high-quality sandstone aggregate from hard rock according to claim 5, which uses a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock for preparation, characterized in that The machine-made sand powder content regulating mechanism is composed of a combined powder classifier, a cyclone dust collector, a circulating fan, a tail-discharge bag dust collector and a tail-discharge fan. The upper air outlet of the combined powder classifier is respectively connected to the cyclone dust collector and the tail-discharge bag dust collector. A circulating fan is arranged between the combined powder classifier and the cyclone dust collector and the tail-discharge bag dust collector. The tail-discharge bag dust collector is connected to the tail-discharge fan.

7. The short-process, low-energy consumption method for preparing high-quality sandstone aggregate from hard rock according to claim 5, which is prepared using a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock, characterized in that The coarse aggregate screening equipment is provided with a first outlet, a second outlet, a third outlet and a fourth outlet under the screen, the first outlet of the coarse aggregate screening equipment is connected to the grinding sand and stone machine through a circulating material conveying belt conveyor, the second outlet of the coarse aggregate screening equipment is connected to the grinding sand and stone machine through a circulating material conveying belt conveyor, the second outlet of the coarse aggregate screening equipment is connected to the finished product warehouse or finished product warehouse through an aggregate finished product conveying belt conveyor, the third outlet of the coarse aggregate screening equipment is connected to the finished product warehouse through an aggregate finished product conveying belt conveyor, the fourth outlet of the coarse aggregate screening equipment is connected to the upper screen inlet of the machine-made sand screening equipment through a slide pipe, and the machine The sand making and screening equipment is provided with a fifth outlet, a sixth outlet and a seventh outlet under the screen. The fifth outlet of the machine-made sand screening equipment is connected to the grinding sand and gravel machine through a circulating material conveying belt conveyor, and the fifth outlet of the machine-made sand screening equipment is connected to the finished product warehouse through an aggregate finished product conveying belt conveyor. The sixth outlet of the machine-made sand screening equipment is connected to the grinding sand and gravel machine through a circulating material conveying belt conveyor, and the sixth outlet of the machine-made sand screening equipment is connected to the inlet of the machine-made sand powder amount regulating mechanism through the machine-made sand semi-finished product conveying belt conveyor. Two products, finished machine-made sand and fine powder, are obtained through the machine-made sand powder content regulating mechanism. The seventh outlet of the machine-made sand screening equipment is connected to the finished product warehouse through the finished product conveying belt conveyor.

8. The short-process, low-energy consumption method for preparing high-quality sandstone aggregate from hard rock according to claim 4, which is prepared using a short-process, low-energy consumption system for preparing high-quality sandstone aggregate from hard rock, characterized in that The vibrating screen is provided with a first outlet, a second outlet and a third outlet. The first outlet of the vibrating screen is connected to the feed port of the grinding sand making machine through a circulating material conveying belt conveyor. The second outlet of the vibrating screen is connected to the grinding sand making machine through a circulating material conveying belt conveyor after connecting a three-way valve. The second outlet of the vibrating screen is connected to a machine-made sand water washing mechanism through a machine-made sand semi-finished product conveying belt conveyor. The third outlet of the vibrating screen is connected to a machine-made sand water machine mechanism through a machine-made sand semi-finished product conveying belt conveyor.

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