Concrete mixing system based on aggregate precooling and control method thereof

Abstract

The invention relates to the technical field of intelligent manufacturing, in particular to a concrete mixing system based on aggregate precooling and a control method thereof. According to the scheme provided by the invention, the pre-cooling storage is arranged into the plurality of isolated aggregate bins, and cooperative control is carried out through various different refrigeration equipment, so that the pre-cooling storage can carry out targeted and independent pre-cooling and cooling on various aggregates such as sand, large stones and small stones according to the characteristics of the aggregates, the cooling effect is good, the pre-cooling time is saved, and the working efficiency is improved. Meanwhile, the aggregate conveying system, the pre-cooling system and the stirring system are integrally arranged, system function modularization is highly integrated, transfer equipment is omitted, and the occupied area is reduced. According to the scheme, the aggregate pre-cooling and batching integrated function is achieved through the pre-cooling storage, the pre-cooling storage can directly replace batching equipment of a mixing plant, secondary heat absorption in the conveying, lifting and temporary storage process after aggregate cooling in a traditional technology is also avoided, the loss of cooling capacity is greatly reduced, and energy consumption is effectively reduced.

Description

Technical Field

[0001] This application relates to the field of intelligent manufacturing technology, specifically to a concrete mixing system based on aggregate pre-cooling and its control method. Background Technology

[0002] With the continuous advancement of major projects such as new infrastructure, large-scale water conservancy hubs, super high-rise buildings, and cross-sea bridges, concrete technology is developing towards high strength, high performance, large volume, and long service life. These projects have placed unprecedentedly stringent requirements on the quality of concrete, especially its crack resistance and durability.

[0003] For large-volume concrete (such as dam bodies, pile caps, and large foundations), the cement hydration reaction generates a large amount of heat, causing a rapid increase in the internal temperature of the structure and creating a huge temperature difference with the surface. This generates thermal stress, and when the stress exceeds the tensile strength of the concrete, cracking occurs, seriously affecting structural safety and service life. One fundamental way to solve this problem is to effectively reduce the discharge temperature and placement temperature of the concrete. Aggregates account for approximately 65%-80% of the concrete raw materials, and their temperature is the main factor determining the final temperature of the concrete mixture.

[0004] In existing aggregate cooling technologies, the cooling of aggregates such as sand and stone is mostly achieved by using cold air or spraying in the silo. However, simply cooling the aggregates on the surface of the silo with cold air is uneven and cannot effectively cool the sand. The spraying system affects the moisture content of the aggregates, which has a significant impact on the performance of concrete.

[0005] Furthermore, in existing aggregate cooling systems, the precooling system, weighing system, batching system, and conveying system are scattered, occupying a large area, with low integration, resulting in a complex control system, more potential failure points, and low automation. Moreover, the aggregate absorbs heat twice during the conveying, lifting, and temporary storage processes after cooling, resulting in significant heat loss and huge energy consumption. Summary of the Invention

[0006] Based on this, this application proposes a concrete mixing system and its control method based on aggregate pre-cooling to address the above problems. The system aims to intelligently, efficiently, and accurately pre-cool the aggregate, effectively control the concrete discharge temperature and placement temperature, improve the quality of the concrete, and ensure the quality of subsequent construction and the safety of the overall project.

[0007] This application provides a concrete mixing system based on aggregate pre-cooling, the concrete mixing system comprising: The aggregate pre-cooling silo is internally divided into multiple aggregate bins, including a sand bin, a small stone bin, and a large stone bin. The small stone bin and the large stone bin are equipped with ventilation windows on one side, which are connected to the first refrigeration unit through air ducts. The sand bin is equipped with a cooling coil, which is connected to the second refrigeration unit through cooling pipes. The first conveying subsystem is located above the aggregate precooling silo and is used to convey the corresponding aggregate to the corresponding aggregate bin for replenishment. The second conveying subsystem is located below the aggregate precooling silo and is used to convey the cooled aggregate to the mixing subsystem. The mixing subsystem, including the mixer unit, is used to mix aggregates to obtain concrete at a preset temperature.

[0008] Furthermore, the top of each aggregate bin is provided with a receiving air valve; the first conveying subsystem includes a horizontal conveying device and a movable material distribution hopper; The movable material distribution hopper can move horizontally and connect with each receiving air valve to transport the received aggregate to the corresponding receiving air valve.

[0009] Preferably, the movable dispensing hopper includes a movable trolley and a dispensing hopper; One side of the movable trolley is fixedly connected to the distribution hopper, and the other side opposite the distribution hopper is set to be inclined to form an inclined lifting section; The aggregate is conveyed by a horizontal conveying device to the inclined lifting section of the moving trolley, and then conveyed to the end of the trolley before entering the distribution hopper.

[0010] Furthermore, the air window includes an air inlet window and an air outlet window. The air inlet window is located at the bottom of the aggregate bin and is connected to the first refrigeration unit through an air inlet pipe to introduce cold air into the aggregate inside the bin. The air outlet is located at the top of the aggregate bin. The air outlet is equipped with a return air device and is connected to the return air pipe of the first refrigeration unit. Under the suction of the return air device, the cold air is circulated back to the first refrigeration unit from bottom to top.

[0011] Furthermore, the small and large stone chambers are equipped with air chambers connected to the corresponding air inlets. The air chambers are arranged across two opposite walls of the stone chamber and have multiple layers of air outlets evenly arranged in the vertical direction.

[0012] Preferably, a regulating valve and a fan are installed at the connection between the air chamber and the air window to adjust the air volume and / or wind speed according to the aggregate temperature.

[0013] Preferably, a conical weighing hopper is provided at the bottom of the aggregate bin, and a weighing sensor is provided inside the weighing hopper; An upper valve is installed at the junction of the bottom of the aggregate bin and the top of the weighing hopper, and a lower valve is installed at the outlet of the weighing hopper.

[0014] Preferably, the cooling coil is a mesh S-shaped coil, and the mesh S-shaped coil is evenly distributed inside the sand chamber at a preset interval; The second refrigeration device is also a liquid-cooled refrigeration device, and can change the direction of liquid flow into the coil.

[0015] Furthermore, the outer layer of the aggregate precooling silo is provided with a cold insulation layer.

[0016] A second aspect of this application provides a concrete production control method based on aggregate precooling, the method being applied to the aforementioned concrete mixing system, the method comprising: The first conveying subsystem is controlled to transport the corresponding aggregate to the corresponding aggregate bin for loading. The temperature of each aggregate is collected, and the first refrigeration device is controlled to generate a preset amount of cold air to be introduced into the large and small stone bins, and the second refrigeration device is controlled to generate a preset amount of liquid cooling to be transported to the sand bin. Determine the proportion of each aggregate according to the current concrete mix ratio, control the opening and closing of the corresponding aggregate bin valves, and release the cooled aggregate for weighing. The weighed aggregates are fed into the second conveying subsystem and then transported to the mixing host for concrete production. The weighed aggregates are fed into the second conveying subsystem and transported to the mixing host for concrete production.

[0017] The concrete mixing scheme based on aggregate pre-cooling provided in this application utilizes a pre-cooling silo structure comprised of multiple isolated aggregate bins, equipped with various refrigeration devices for coordinated control. This allows the pre-cooling silo to selectively pre-cool various aggregates (sand, large stones, and small stones) according to their characteristics, resulting in effective cooling, reduced pre-cooling time, and improved work efficiency. Furthermore, this scheme integrates the aggregate conveying system, pre-cooling system, and mixing system into a single, highly integrated modular design. This eliminates the need for intermediate transfer equipment, reduces floor space requirements, and is suitable for diverse construction needs and scenarios. Moreover, this scheme integrates aggregate pre-cooling and batching functions through the pre-cooling silo, which can directly replace the batching equipment in the mixing plant. This also avoids secondary heat absorption during the conveying, lifting, and temporary storage of cooled aggregates, significantly reducing cold loss and effectively saving energy.

[0018] Furthermore, this application's solution integrates a PLC system. When aggregates enter the silo, the system automatically calculates the required cooling time and refrigeration capacity based on the initial temperature, type, and weight of the aggregates, achieving fully automated operation. The entire process of cooling, heat preservation, batching, and weighing is automated, ensuring that the aggregate and concrete outlet temperatures remain stable at the set values. Attached Figure Description

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

[0020] in: Figure 1 This is a schematic diagram of a concrete mixing system architecture based on aggregate precooling in one embodiment; Figure 2 This is a full-scale structural schematic diagram of a concrete mixing system based on aggregate precooling in one embodiment; Figure 3 This is a schematic diagram of a single-line aggregate precooling silo in one embodiment; Figure 4 This is a full-scale structural diagram of a single-line aggregate precooling silo in one embodiment; Figure 5 This is a schematic diagram of the ventilation shafts inside the large and small stone warehouses in one embodiment; Figure 6 This is a flowchart of a concrete control method based on aggregate precooling in one embodiment. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] The terms "comprising," "including," and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus. Terms such as "first" and "second," and other relational terms, in the claims, specification, and accompanying drawings of this application, are used merely to distinguish one entity / operation / object from another, and do not necessarily require or imply any such actual relationship or order between these entities / operations / objects.

[0023] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase at various points in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0024] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0025] In one implementation, such as Figure 1 The diagram shown is a schematic representation of a concrete mixing system architecture based on aggregate precooling according to this application. The system includes an aggregate precooling silo, a first conveying subsystem, a second conveying subsystem, and a mixing subsystem. Specifically, the concrete mixing system based on aggregate precooling includes: An aggregate pre-cooling silo is internally divided into multiple aggregate bins. Preferably, in one embodiment of this application, a single aggregate pre-cooling silo is divided into three aggregate bins of different volumes. These three bins can be configured according to the type of aggregate: a sand bin, a medium-to-large stone bin (e.g., with a particle size greater than 10mm), and a small stone bin (e.g., with a particle size of 5-10mm). The volumes of the three bins can be set according to actual needs, such as a 2:1:2 ratio (suitable for conventional concrete aggregate mix proportions). In specific implementation, the corresponding volumes of aggregate bins can be set as sand bins, small stone bins, and large stone bins based on the specific current concrete mix proportions and requirements. For example, if the current concrete mix requires more large stone aggregate than small stone aggregate, the volume ratio of the large stone bin to the small stone bin can be set to 2:1, and vice versa. This allows for adaptation to different construction scenarios and concrete mix proportion requirements. Specifically, the solution of this application can be implemented based on one or more single-line aggregate pre-cooling silos according to actual production needs.

[0026] The first conveying subsystem is located above the aggregate pre-cooling silo and is used to convey the corresponding aggregate to the corresponding aggregate bin for replenishment. Specifically, when the first conveying subsystem of this application is implemented based on multiple single-line aggregate pre-cooling silos, a single first conveying subsystem can be shared, and the first conveying subsystem is located above all aggregate pre-cooling silos to convey the aggregate from above to the corresponding aggregate bin for pre-cooling.

[0027] The second conveying subsystem, located below the aggregate precooling silo, is used to transport the cooled aggregate to the mixing unit. Preferably, to reduce cold loss, the second conveying subsystem can be a short-distance, enclosed, and insulated second conveyor belt unit. The second conveying subsystem can be set below each precooling silo according to the number of silos, so that after the precooled aggregate is conveyed to the corresponding second conveyor belt, it is directly conveyed into the corresponding mixing unit, thus reducing the individual conveying paths and cold loss.

[0028] The mixing subsystem, including a mixer unit, is used to mix aggregates to obtain concrete at a preset temperature. Specifically, the mixing subsystem is located near the second conveying subsystem, either below or in a nearby location. The second conveying subsystem transports the pre-cooled aggregates to the corresponding inlet of the mixing subsystem. Furthermore, the mixing subsystem can be equipped with other raw material feeding stations as needed, including stations for cement, fly ash, water, admixtures, etc. Preferably, in one embodiment of this application, after the cold aggregates are added to the mixer unit, they can be briefly dry-mixed to make their temperature distribution more uniform before adding cold water and camphor to maximize the utilization of the coldness of the aggregates and reduce the amount of mixing water used. In addition, the above-mentioned mixing subsystem also integrates a control system to control and coordinate the feeding sequence of the aggregate pre-cooling weighing system and other raw material systems, and to control the specific mixing process. When the pre-cooled aggregates begin to be unloaded and collected, the metering and addition of cementitious materials such as cement and fly ash can also be controlled simultaneously to achieve material coordination in time and space.

[0029] Specifically, in one embodiment, such as Figure 2 The figure shown is a full-scale structural schematic diagram of a concrete mixing system based on aggregate precooling in one embodiment of this application. Each aggregate bin is provided with a receiving air valve on its top. The number of receiving air valves on the top of each aggregate bin can be set to one or more according to the volume of each aggregate bin.

[0030] Preferably, in one embodiment of this application, the first conveying subsystem of the above-mentioned scheme includes a horizontal conveying device and a movable material distribution hopper. The movable material distribution hopper can move horizontally to connect with each receiving air valve port to convey the received aggregate to the corresponding receiving air valve port.

[0031] Preferably, the movable distribution hopper includes a movable trolley and a distribution hopper fixedly connected to one side of the movable trolley. The other side of the movable trolley is inclined to form an inclined lifting section. The overall support structure of the movable trolley is triangular (e.g., a right triangle), and its side opposite the distribution hopper is inclined to form an inclined lifting section. Further, the first transmission system also includes a first conveyor belt. The inclined lifting section and the horizontal conveying device are connected via the same first conveyor belt to transmit aggregates. Alternatively, different first conveyor belts can be used to collaboratively transmit aggregates. The horizontal conveying device and the inclined conveying section include corresponding conveyor units, each including an active or driven wheel set to drive the conveyor belt to transmit aggregates. The aggregates are transmitted from the horizontal conveying device to the inclined lifting section of the movable trolley, and then conveyed to the end of the inclined lifting section before entering the distribution hopper. The movable distribution hopper can move horizontally back and forth along the track and connect with the receiving air valve at the top of each aggregate bin.

[0032] Preferably, in this application, the inclined lifting section and the horizontal conveying device are connected by the same first conveyor belt for conveying aggregate. The first conveyor belt is an integral conveyor belt. In this embodiment, the horizontal conveying device is divided into a first horizontal conveying section and a second horizontal conveying section by a movable trolley. The movable trolley can move back and forth along the entire horizontal conveying device through the wheel set at its bottom, and changes the relative length of the first horizontal conveying section and the second horizontal conveying section during the movement. A reversing wheel is provided at the upper end of the inclined lifting section of the movable trolley, and the first conveyor belt changes its transmission direction at the upper end of the inclined lifting section via the reversing wheel.

[0033] In the above-described scheme of this application, the aggregate is conveyed to the inclined lifting section via the horizontal conveying device of the first conveyor belt. After being conveyed and lifted to a preset height by the inclined lifting section, it reaches the end and enters the distribution hopper by gravity and inertia. The lower part of the distribution hopper is provided with a discharge port that can precisely connect with the inlet air valve at the top of each pre-cooling hopper. This discharge port can be a controllable switch valve, which can flexibly control the opening and closing of the valve and convey the aggregate to the corresponding receiving air valve into each aggregate hopper.

[0034] Furthermore, in one embodiment, the length of the first conveying subsystem provided in this application can be flexibly adjusted as needed to adapt to different construction scenarios with varying numbers of pre-cooling silos. Compared to traditional pre-cooling mixing plant systems that require large aggregate stockpiles, multiple conveyor belts, and independent pre-cooling silos, the solution in this application integrates the stockpiles, pre-cooling silos, and batching stations into a vertical layout, significantly reducing the floor space. The movable distribution hopper enables a single main feeding line to serve different cooling aggregate bins in multiple pre-cooling silos, greatly simplifying the top structure. Simultaneously, the first conveying subsystem in this application dynamically and precisely couples the aggregate conveying and cooling silo feeding processes via the same conveyor belt, greatly improving the continuity and automation level of the entire system.

[0035] In one embodiment, such as Figure 3-4 In the schematic diagram of a single-line aggregate precooling silo and the corresponding full-scale structural schematic diagram of the single-line aggregate precooling silo, the small and large stone silos in the above-mentioned scheme of this application are provided with ventilation windows on one side. The number of ventilation windows can be set according to the volume of the corresponding small and large stone silos. The ventilation windows are connected to the first refrigeration unit through air ducts.

[0036] The air vents include an air inlet vent and an air outlet vent. The air inlet vent is located at the bottom of the aggregate bin and is connected to the first refrigeration unit via an air inlet pipe to introduce cold air into the aggregate bin. The air outlet vent is located at the top of the aggregate bin and is equipped with a return air device. The return air device can be a suction fan with adjustable and controllable wind speed and is connected to the return air pipe of the first refrigeration unit. Under the suction of the return air device, the cold air is circulated from bottom to top through the return air vent back to the first refrigeration unit. Furthermore, each aggregate bin can be equipped with an arc-shaped air guide plate as needed to form a "bottom-in, top-out" vortex airflow field to improve the precooling efficiency and effect of the aggregate in the corresponding aggregate bin.

[0037] Furthermore, in one embodiment, such as Figure 5 The diagram shows a schematic of the internal ventilation section of a large and small aggregate storage silo. The ventilation section, connected to corresponding air inlets, spans two opposite walls of the silo, forming an "air wall" to ensure airflow covers the entire cross-section of the silo and eliminates cooling dead zones. Furthermore, the ventilation section has multiple layers of air outlets evenly distributed vertically. For example, on one side wall of the ventilation section (facing the aggregate pile), multiple layers and rows of air outlets (such as strip-shaped air outlets or arrayed circular holes) are evenly distributed vertically. This ensures that cold air is evenly delivered from the bottom of the aggregate pile upwards, achieving more comprehensive and penetrating cooling of the deep aggregate pile. This results in a large contact area and long contact time (long penetration path) between the cold air and the aggregate, effectively solving the problems of "airflow short-circuiting" and insufficient central cooling caused by traditional lateral air supply.

[0038] Preferably, in one embodiment, a regulating valve and a fan are installed at the connection between the air chamber and the air vent in the above-described solution of this application, so as to adjust the opening degree of the air inlet valve and / or the speed of the fan according to the aggregate temperature. The fan is installed at the air inlet end of the air chamber and its speed is adjustable. The regulating valve is installed at the air chamber inlet and / or the corresponding air outlet, used to precisely distribute and adjust the air volume delivered to the air outlets at different height levels. The working logic of the above-described solution of this application is as follows: After the first refrigeration unit generates cold air, which enters through the air inlet, the cold air is further pressurized or its speed adjusted by the fans in the corresponding air chamber. Combined with distribution via regulating valves, the air enters the transverse air chamber and is finally evenly sprayed into the aggregate pile from the multi-layered air outlets. This allows the cold air to penetrate more evenly and effectively to the opposite side of the aggregate pile away from the air chamber. It also facilitates more efficient and rapid return of the cold air to the corresponding return air channel, thereby achieving sufficient, uniform, and efficient heat exchange between the aggregate and the cold air in the aggregate bin. This improves the pre-cooling effect of the aggregate, significantly shortens the cooling time, increases project efficiency, and reduces energy consumption.

[0039] Furthermore, in the above-mentioned scheme of this application, each subsystem is connected to the central control system (PLC) via wired or wireless communication. The central control system can send control commands to each subsystem and obtain the temperature of the air outlet, air return outlet and key points of the material pile in real time. Based on the initial temperature, target temperature and real-time temperature difference, it dynamically generates adjustment commands to adjust the corresponding valve opening and / or fan speed, thereby realizing the adjustment of precise cooling on demand.

[0040] Preferably, in one embodiment, the sand silo of this application is provided with cooling coils, which are connected to a second refrigeration device via external cooling pipes (such as cooling water pipes). Preferably, the cooling coils are multiple sets of mesh S-shaped coils, which are installed vertically and in multiple rows in parallel (the spacing between coil groups is greater than 250mm), and are evenly distributed inside the sand silo at preset intervals. The mesh S-shaped coils are arranged three-dimensionally at preset uniform intervals across the entire cross-section and depth inside the sand silo, forming a "cold skeleton" embedded inside the material pile. The mesh S-shaped coils are connected end to end or eventually converge, and are connected to the second refrigeration device via external cooling pipes to form a closed cold liquid circulation loop. In one embodiment, corresponding heat-conducting fins can also be provided on the surface of the mesh S-shaped coils to increase the heat exchange rate. The second refrigeration device is a liquid-cooled refrigeration unit (such as a chilled water or ethylene glycol aqueous solution refrigeration unit), and can change the direction of liquid cooling flowing into the coil, so as to change the direction of cold source flowing into / out of the sand chamber according to the temperature in the sand chamber, so as to achieve uniform and rapid pre-cooling and cooling.

[0041] The sand silo described in this application is filled with low-temperature cooling liquid, and the coils are uniformly distributed in three dimensions, which allows the cooling capacity to be released simultaneously from multiple points and directions inside the material pile. This completely eliminates the cooling dead zones and temperature gradients caused by traditional air cooling or wall-mounted coils, achieving uniform and deep cooling of the sand. At the same time, the coil system also has the function of breaking arches to prevent sand from caking.

[0042] Preferably, in one embodiment of this application, such as Figure 3-4As shown, a conical weighing hopper is installed at the bottom of each aggregate bin. The conical weighing hopper is an independent, small-capacity, conical steel structure container. A weighing sensor is installed inside the weighing hopper. Specifically, one or more high-precision weighing sensors can be installed on the corresponding support structure inside the weighing hopper, making it a completely independent "weighing platform".

[0043] Furthermore, an upper valve is installed at the junction of the bottom of the aggregate bin and the top of the weighing hopper, and a lower valve is installed at the outlet of the weighing hopper. Preferably, the upper valve can be a large-diameter sealing gate valve or a double-disc butterfly valve, whose core function is isolation and sealing. When the valve is closed, it can effectively and completely cut off the material flow and completely separate the aggregate load in the aggregate bin from the weighing system below. The lower valve (i.e., the discharge valve) is located at the conical outlet of the weighing hopper and can be a precision arc gate or a fast pneumatic gate valve. It can open and close quickly, has good sealing performance, and allows for smooth discharge to control the discharge and conveying to the collecting belt.

[0044] The upper valve, lower valve, and weighing sensor system of the above-mentioned scheme in this application are all connected to the PLC control system, forming an automated closed-loop process of "upper valve opens to unload - sensor weighs in real time - upper valve closes after reaching the set value - lower valve opens to feed after weighing is completed". It can effectively replace the traditional unloading valve, has a high degree of integration, improves the overall unloading adjustment accuracy of the system, and shortens the system response delay time.

[0045] Furthermore, in the above-described scheme of this application, a cold insulation layer is provided on the outer layer of the aggregate precooling silo. For example, a polyurethane rigid foam insulation layer with a first-class thermal insulation performance is used on the outer layer of each bin of the aggregate precooling silo, and a guide plate is added to the inner side of the bin wall to reduce airflow dead zones.

[0046] In one embodiment, such as Figure 6 The diagram shown is a flowchart of a concrete production control method based on aggregate pre-cooling provided in the second aspect of this application. The method is applied to the aforementioned concrete mixing system and includes: The first conveying subsystem is controlled to transport the corresponding aggregate to the corresponding aggregate bin for loading. The temperature of each aggregate is collected, and the first refrigeration device is controlled to generate a preset amount of cold air to be introduced into the large and small stone bins, and the second refrigeration device is controlled to generate a preset amount of liquid cooling to be transported to the sand bin. Based on the preset pre-cooling time of each cold source for the corresponding aggregate, until the aggregate reaches the target temperature; Determine the proportion of each aggregate according to the current concrete mix ratio, control the opening and closing of the corresponding aggregate bin valves, and release the cooled aggregate for weighing. The weighed aggregate is fed into the second conveying subsystem and then transported to the mixing host for concrete production.

[0047] Specifically, controlling the first refrigeration device to generate a preset amount of cold air to be supplied to the large and small stone silos includes: determining the required amount of cold air W based on the current temperature and target temperature of each stone silo, wherein the amount of cold air satisfies: Where mi is the total weight of the air-cooled aggregate required for the i-th quarry, Ci is the specific heat of the i-th aggregate, and T is the total weight of the air-cooled aggregate required for the i-th quarry. 1i Let T be the temperature of the i-th pre-cooling silo. 2i The expected temperature of the i-th aggregate bin after a pre-cooling preset time; γ is the bulk density of the cooling medium (air), which is taken as the bulk density of the incoming air in the calculation. 1i I 2i These are the enthalpy of the air entering and exiting the i-th precooling regulating silo, respectively.

[0048] In one embodiment, this application also provides a computer control system, including a computer control device. The computer device includes a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor causes the processor to perform the following steps: The first conveying subsystem is controlled to transport the corresponding aggregate to the corresponding aggregate bin for loading. The temperature of each aggregate is collected, and the first refrigeration device is controlled to generate a preset amount of cold air to be introduced into the large and small stone bins, and the second refrigeration device is controlled to generate a preset amount of liquid cooling to be transported to the sand bin. Based on the preset pre-cooling time of each cold source for the corresponding aggregate, until the aggregate reaches the target temperature; Determine the proportion of each aggregate according to the current concrete mix ratio, control the opening and closing of the corresponding aggregate bin valves, and release the cooled aggregate for weighing. The weighed aggregate is fed into the second conveying subsystem and then transported to the mixing host for concrete production.

[0049] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0050] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A concrete mixing system based on aggregate pre-cooling, characterized in that, The concrete mixing system includes: The aggregate pre-cooling silo is internally divided into multiple aggregate bins, including a sand bin, a small stone bin, and a large stone bin. The small stone bin and the large stone bin are equipped with ventilation windows on one side, which are connected to the first refrigeration unit through air ducts. The sand bin is equipped with a cooling coil, which is connected to the second refrigeration unit through cooling pipes. The first conveying subsystem is located above the aggregate precooling silo and is used to convey the corresponding aggregate to the corresponding aggregate bin for replenishment. The second conveying subsystem is located below the aggregate precooling silo and is used to convey the cooled aggregate to the mixing subsystem. The mixing subsystem, including the mixer unit, is used to mix aggregates to obtain concrete at a preset temperature.

2. The concrete mixing system according to claim 1, characterized in that, Each of the aggregate bins is equipped with a material receiving air valve at its top. The first conveying subsystem includes a horizontal conveying device and a movable dispensing hopper; The movable material distribution hopper can move horizontally and connect with each receiving air valve to transport the received aggregate to the corresponding receiving air valve.

3. The concrete mixing system according to claim 2, characterized in that, The movable material distribution hopper includes a movable trolley and a material distribution hopper; One side of the movable trolley is fixedly connected to the distribution hopper, and the other side opposite the distribution hopper is set to be inclined to form an inclined lifting section; The aggregate is conveyed by a horizontal conveying device to the inclined lifting section of the moving trolley, and then conveyed to the end of the trolley before entering the distribution hopper.

4. The concrete mixing system according to claim 1, characterized in that, The air window includes an air inlet window and an air outlet window. The air inlet window is located at the bottom of the aggregate bin and is connected to the first refrigeration unit through an air inlet pipe to introduce cold air into the aggregate inside the bin. The air outlet is located at the top of the aggregate bin. The air outlet is equipped with a return air device and is connected to the return air pipe of the first refrigeration unit. Under the suction of the return air device, the cold air is circulated back to the first refrigeration unit from bottom to top.

5. The concrete mixing system according to claim 4, characterized in that, The small and large stone chambers are equipped with air chambers connected to corresponding air inlets. The air chambers are set across two opposite walls of the stone chamber and have multiple layers of air outlets evenly arranged vertically.

6. The concrete mixing system according to claim 5, characterized in that, The air chamber is equipped with a regulating valve and a fan at the connection with the air window to adjust the air volume and / or wind speed according to the aggregate temperature.

7. The concrete mixing system according to claim 1, characterized in that, The bottom of the aggregate bin is equipped with a conical weighing hopper, and a weighing sensor is installed inside the weighing hopper; An upper valve is installed at the junction of the bottom of the aggregate bin and the top of the weighing hopper, and a lower valve is installed at the outlet of the weighing hopper.

8. The concrete mixing system according to claim 1, characterized in that, The cooling coil is a mesh S-shaped coil, which is evenly distributed inside the sand chamber at preset intervals. The second refrigeration device is a liquid-cooled refrigeration device, and the direction of liquid flow into the coil can be changed.

9. The concrete mixing system according to any one of claims 1-7, characterized in that, The outer layer of the aggregate pre-cooling silo is equipped with a cold insulation layer.

10. A method for controlling concrete mixing based on aggregate pre-cooling, said method being applied to the mixing system as described in any one of claims 1-9, characterized in that, The method includes: The first conveying subsystem is controlled to transport the corresponding aggregate to the corresponding aggregate bin for loading. The temperature of each aggregate is collected, and the first refrigeration device is controlled to generate a preset amount of cold air to be introduced into the large and small stone bins, and the second refrigeration device is controlled to generate a preset amount of liquid cooling to be transported to the sand bin. Based on the preset pre-cooling time of each cold source for the corresponding aggregate, until the aggregate reaches the target temperature; Determine the proportion of each aggregate according to the current concrete mix ratio, control the opening and closing of the corresponding aggregate bin valves, and release the cooled aggregate for weighing. The weighed aggregate is fed into the second conveying subsystem and then transported to the mixing host for concrete production.

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