A continuously operating ammonium nitrate explosive delivery system

Abstract

This invention relates to equipment for on-site mixing of ammonium nitrate (AM) explosives, specifically a continuously operating AM explosive conveying system. It includes two conveyors, each capable of holding porous granular ammonium nitrate. Each conveyor is connected to a flexible hose mounted on the telescopic boom of an AM explosive vehicle. The end of the flexible hose is equipped with a vortex cone, which is connected to a static mixing device. After one conveyor pneumatically delivers the porous granular ammonium nitrate to the flexible hose, the system switches to the other conveyor for further pneumatic conveying. The fuel for the AM explosive and the pneumatically delivered porous granular ammonium nitrate are respectively conveyed into the vortex cone for initial vortex mixing before flowing into the static mixing device for repeated cross-mixing. This improves the uniformity of the explosive mixture and enhances the blasting effect. Furthermore, by using two conveyors, this invention enables continuous pneumatic conveying of AM explosives without requiring downtime for refueling, thus improving operational efficiency.

Description

Technical Field

[0001] This invention relates to equipment for on-site mixing of ammonium nitrate explosives, specifically an ammonium nitrate explosives conveying system capable of continuous operation. Background Technology

[0002] Ammonium nitrate (AM) explosives are powdery or granular explosive mixtures composed of ammonium nitrate and fuel. They are primarily suitable for open-pit blasting operations and blasting projects without the risk of methane or mine dust explosions. AM explosives include powdered AM explosives and porous granular AM explosives. In the blasting industry, to improve safety, mixing trucks are increasingly being used for on-site mixing of explosives. Currently, on-site mixing of AM explosives involves separately conveying porous granular ammonium nitrate and fuel to a mixer at the end of a hose for mixing before conveying to the borehole. The porous granular ammonium nitrate is typically conveyed via a screw conveyor, which is not only slow and prone to clogging, but also requires stopping the machine and refilling the hopper once the granular ammonium nitrate in the hopper is depleted, preventing continuous explosive delivery and impacting project progress. Furthermore, existing hose-end mixers do not provide uniform mixing of the explosives; unevenly delivered explosives to the borehole affect the blasting effect. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a continuously operating ammonium nitrate explosive delivery system with high conveying efficiency and uniform mixing.

[0004] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: a continuously operating ammonium nitrate explosive conveying system, which includes two conveyors that can respectively hold porous granular ammonium nitrate. Each conveyor is connected to a flexible hose installed on the telescopic arm of the ammonium nitrate explosive vehicle. The end of the flexible hose is provided with a vortex cone tube, which is connected to a static mixing device. After one conveyor pneumatically conveys the porous granular ammonium nitrate to the flexible hose, it switches to the other conveyor for pneumatic conveying. The fuel of the ammonium nitrate explosive and the porous granular ammonium nitrate pneumatically conveyed by the conveyor are respectively conveyed to the vortex cone tube for initial vortex mixing and then flow into the static mixing device for repeated cross-mixing, and then converge and flow into the borehole.

[0005] Preferably, each conveyor includes a cylindrical outer shell mounted on the frame of an ammonium nitrate explosive (AMFE) vehicle. The outer shell contains a conical cavity with a larger upper diameter and a smaller lower diameter. A feed hopper is located on the upper side of the outer shell. A partition is formed between the outer shell and the cavity, and a blower unit is installed within this partition. A discharge channel connected to the flexible hose is also provided within the partition. After the porous granular ammonium nitrate in the feed hopper enters the cavity, the heat generated by the blower unit preheats the cavity. Furthermore, the air supplied by the blower unit to the cavity blows the porous granular ammonium nitrate to the discharge channel, and then into the flexible hose.

[0006] Preferably, the top of the cavity has a feed inlet communicating with the feed bin, and the lower side wall of the cavity has a strong air inlet. Below the strong air inlet, on the lower side wall of the cavity, there are a main discharge outlet and an auxiliary discharge outlet, both communicating with the discharge channel. The inner wall of the cavity has a spiral-shaped air duct, the upper end of which connects to the strong air inlet, the middle part to the main discharge outlet, and the lower end to the auxiliary discharge outlet. The bottom of the cavity has a weak air inlet. Air inlet; After the porous granular ammonium nitrate enters the cavity through the feed inlet, the strong air supplied by the blower unit through the strong air inlet flows along the air duct to form a vortex, which blows the porous granular ammonium nitrate flowing to the lower part of the cavity downward to the main discharge port, and then flows into the discharge channel. The weak air supplied by the blower unit through the weak air inlet through the weak air inlet blows the remaining porous granular ammonium nitrate flowing to the bottom of the cavity upward to the auxiliary discharge port, and then flows into the discharge channel.

[0007] Preferably, a guide plate is inclinedly arranged inside the cavity. The lower end of the guide plate is connected to the auxiliary discharge port, and the higher end is located on the lower side of a corresponding section of the air duct. Several air holes are opened on the guide plate. A weak wind blows into the air holes to blow the remaining porous granular ammonium nitrate to the auxiliary discharge port.

[0008] Preferably, the inner wall of the cavity is provided with a mounting groove along the circumference, and the periphery of the guide plate is arranged in the mounting groove. Half of the mounting groove coincides with a section of the air duct from the auxiliary discharge port to its opposite position, and the other half of the mounting groove is symmetrical to the first half. A circular opening is provided on the guide plate near the auxiliary discharge port, and two retaining strips extend from both sides of the opening. The two retaining strips are engaged with the auxiliary discharge port. The axis of the weak air inlet passes through the opening, and the weak air delivered by the weak air inlet blows towards the opening to blow the residual porous granular ammonium nitrate to the auxiliary discharge port.

[0009] Preferably, the guide plate located in the half-section of the mounting groove has several grooves, each groove extending from the edge of the guide plate to the opening, and several air holes are formed at the bottom of each groove; several air guide slots are formed on the inner wall of the cavity from the weak air inlet to the mounting groove, and a notch is provided on the edge of the guide plate corresponding to each air guide slot, and each groove is connected to a notch.

[0010] Preferably, the top of the outer shell is provided with a cover plate that covers and encloses the top of the cavity, the feed bin is disposed on the cover plate, and the feed inlet is opened on the cover plate; the bottom of the outer shell is provided with a bottom plate that covers and encloses the bottom of the cavity, the weak air inlet is opened on the bottom plate, and the blower unit includes a strong blower and a weak air inlet installed on the bottom plate, the strong blower delivers strong air to the strong air inlet, and the weak blower delivers weak air to the weak air inlet.

[0011] Preferably, the vortex cone has a large upper diameter and a small lower diameter. One side of the upper end of the vortex cone is connected to the end of the hose, and the other side of the upper end of the vortex cone is connected to a fuel pipe for conveying fuel for ammonium nitrate explosive. The porous granular ammonium nitrate conveyed by pneumatics generates a vortex in the inner cavity of the vortex cone and is initially mixed with the fuel before flowing from the lower end of the vortex cone into the intermediate connector, and then from the intermediate connector into the static mixing device.

[0012] Preferably, the static mixing device includes an outer pipe connected to the intermediate joint and a mixing unit disposed within the outer pipe. The mixing unit includes three sections connected in sequence: front, middle and rear. Each section is formed by splicing several vertically intersecting frames into a grid shape. The mixture is first dispersed into multiple streams of fluid in the grid shape, and then repeatedly cross-mixed within the grid shape.

[0013] Preferably, each grid segment is formed by splicing together two sets of perpendicularly intersecting frames. Each set of frames contains three parallel frames. One frame in one set includes a frame formed according to the inner wall of the outer tube and three horizontal bars arranged perpendicular to the frame. Each horizontal bar is perpendicularly connected to the corresponding frame in the other set of frames to form a grid. The three horizontal bars are connected by two vertically arranged vertical bars. The two ends of each vertical bar extend to abut against the inner wall of the outer tube. Each horizontal bar is divided into three segments, one of which is connected to the frame and the other two segments are respectively connected to the two vertical bars.

[0014] As can be seen from the above technical solutions, this invention enables continuous pneumatic conveying of ammonium nitrate explosives by setting up two conveyors, eliminating the need for stopping the machine to add fuel and improving operational efficiency. Simultaneously, this invention utilizes the pneumatic pressure of conveying porous granular ammonium nitrate and incorporates a swirling cone tube, allowing the fuel and porous granular ammonium nitrate to undergo initial mixing under swirling action. Then, the mixture is dispersed into multiple streams through a three-section grid-like static mixing device for repeated cross-mixing, improving the uniformity of the explosive mixture and enhancing the blasting effect. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention.

[0016] Figure 2 This is a cross-sectional structural diagram of a preferred embodiment of the conveyor in this invention.

[0017] Figure 3 This is a schematic diagram of the installation structure of the guide plate in this invention.

[0018] Figure 4 This is a schematic diagram of the preferred configuration of the hybrid unit in this invention.

[0019] Figure 5 This is a structural schematic diagram of one of the frameworks of the present invention.

[0020] Figure 6 This is a schematic diagram of the grid-like projection of the present invention. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0022] like Figure 1 As shown, this invention provides a continuously operating ammonium nitrate (AM) explosive delivery system, comprising two conveyors 4 for holding porous granular ammonium nitrate. Each conveyor is connected to a flexible hose 101 mounted on the telescopic arm of an AM explosive vehicle. The end of the flexible hose is equipped with a vortex cone 102, which is connected to a static mixing device 41. After one conveyor pneumatically delivers the porous granular ammonium nitrate to the flexible hose, the system switches to the other conveyor for pneumatic delivery, thus achieving continuous pneumatic delivery of AM explosives. During implementation, the switching control can be automatically controlled using sensors and solenoid valves. When the sensor detects that the porous granular ammonium nitrate in one conveyor has been delivered, it controls the solenoid valve of that conveyor to close, allowing for resupply; and automatically controls the solenoid valve of the other conveyor to open, achieving continuous delivery. The fuel for the AM explosive and the porous granular ammonium nitrate pneumatically delivered by the conveyors are respectively delivered to the vortex cone for initial vortex mixing before flowing into the static mixing device for repeated cross-mixing, and then converging before flowing into the borehole. Therefore, the repeated cross-mixing of the initial mixing in the swirl cone tube and the static mixing device greatly improves the uniformity of the explosive mixture, ensuring the detonation effect. Simultaneously, this invention utilizes the air pressure of pneumatically conveyed porous granular ammonium nitrate to achieve swirl initial mixing, eliminating the need for additional power, thus saving energy and reducing costs.

[0023] like Figure 2 and Figure 3Each conveyor 4 of the present invention includes a cylindrical outer shell 5 mounted on the frame of an ammonium nitrate explosive vehicle. The outer shell contains a conical cavity 1 with a larger diameter at the top and a smaller diameter at the bottom. This structure allows porous granular ammonium nitrate to accumulate in the smaller lower part, which is beneficial for centralized conveying. A feed bin 6 is provided on the upper side of the outer shell. A partition 7 is formed between the outer shell and the cavity. A blower unit is installed in the partition 7. A discharge channel 3 connected to the hose is provided in the partition 7. After the porous granular ammonium nitrate in the feed bin enters the cavity, the heat generated by the blower unit heats the cavity to preheat the porous granular ammonium nitrate. The air delivered by the blower unit to the cavity blows the porous granular ammonium nitrate to the discharge channel, then flows into the hose, and is mixed with fuel in a vortex cone tube and a static mixing device to form explosives, which are then conveyed to the blast hole. As can be seen, compared with screw conveying, the present invention realizes pneumatic conveying, which is not only less prone to blockage, but also improves the conveying speed, makes the conveying more uniform, and is safer; moreover, it preheats the porous granular ammonium nitrate, which improves the uniformity of subsequent explosive mixing and detonation sensitivity.

[0024] Preferably, the top of the cavity is provided with a feed inlet 11 communicating with the feed bin, the lower side wall of the cavity is provided with a strong air inlet 12, and the lower side wall of the cavity, below the strong air inlet, is provided with a main discharge outlet 13 and an auxiliary discharge outlet 14, both communicating with the discharge channel 3. The inner wall of the cavity is provided with a spiral air duct 15, the upper end of which is connected to the strong air inlet, the middle part of which is connected to the main discharge outlet, and the lower end of which is connected to the auxiliary discharge outlet. The bottom of the cavity is provided with a weak air inlet 16. During implementation, after the porous granular ammonium nitrate enters the cavity through the feed inlet, the blower unit delivers strong air under positive pressure through the strong air inlet, which flows along the air duct to form a vortex, blowing the porous granular ammonium nitrate flowing towards the lower part of the cavity downwards to the main discharge port, and then into the discharge channel. Simultaneously, the blower unit delivers weak air under positive pressure through the weak air inlet, blowing the remaining porous granular ammonium nitrate flowing towards the bottom of the cavity upwards to the auxiliary discharge port, and then into the discharge channel. Thus, this invention achieves pneumatic conveying of porous granular ammonium nitrate through a dual blowing method of top-down and bottom-up, ensuring not only more uniform conveying but also less clogging and more thorough blowing.

[0025] The "strong wind" used in this invention refers to the air delivered by the blower unit with a relatively high forward pressure, while the "weak wind" refers to the air delivered by the blower unit with a relatively low forward pressure. Since the porous granular ammonium nitrate enters the cavity from the top, it falls downwards under its own gravity. When it falls to the lower part of the cavity, a swirling strong wind disperses it and evenly conveys it downwards to the main discharge port. During implementation, a small portion of the porous granular ammonium nitrate may fall to the bottom of the cavity under the influence of gravity, overcoming the strong wind. Therefore, this invention incorporates an upward weak wind at the bottom to "support" the remaining porous granular ammonium nitrate, preventing it from "settling" at the bottom of the cavity. This allows it to be blown to the auxiliary discharge port to "merge" with the porous granular ammonium nitrate in the main discharge port, ensuring more thorough delivery of the porous granular ammonium nitrate and avoiding residue.

[0026] Specifically, a guide plate 2 is inclinedly arranged inside the cavity 1. The lower end of the guide plate is connected to the auxiliary discharge port, and the higher end is located on the lower side of the corresponding section of the air duct. This allows all residual porous granular ammonium nitrate to fall onto the guide plate, and the inclined guide plate can guide the porous granular ammonium nitrate to the auxiliary discharge port, further avoiding the residue of porous granular ammonium nitrate. Several air holes 21 are opened on the guide plate 2. A weak airflow blows through the air holes to blow the residual porous granular ammonium nitrate to the auxiliary discharge port, avoiding the residue of porous granular ammonium nitrate on the guide plate. Preferably, the inner wall of the cavity is provided with a mounting groove 17 along the circumference. The periphery of the guide plate is disposed in the mounting groove. Half of the mounting groove coincides with a section of the air duct from the auxiliary discharge port to its opposite position. The other half of the mounting groove is symmetrical to the first half. That is, half of the edge of the guide plate is disposed in the air duct, and the other half of the edge of the guide plate is disposed on the lower side of the corresponding air duct through the symmetrical mounting groove. When the strong wind blows most of the porous granular ammonium nitrate to the main discharge port, a small part of the strong wind may still pass over the main discharge port and flow along the lower section of the air duct. Thus, in the swirling action, the porous granular ammonium nitrate remaining in this section is blown by the strong wind to the guide plate on the lower side. When the strong wind flows to contact the guide plate, the edge of the guide plate in the air duct collides with the strong wind, thereby disrupting the swirling effect of the strong wind, thus stopping the strong wind flow and guiding the guide plate. This blows all the porous granular ammonium nitrate on the guide plate to the auxiliary discharge port at the lower end of the guide plate, completely avoiding the residue of porous granular ammonium nitrate on the guide plate.

[0027] A circular opening 22 is provided on the guide plate 2 near the auxiliary discharge port. Two retaining strips 23 extend from both sides of this opening, engaging with the auxiliary discharge port. This facilitates not only the placement of the guide plate but also the guiding of porous granular ammonium nitrate to the auxiliary discharge port. During implementation, a weak airflow from the bottom blows towards this opening, carrying any remaining porous granular ammonium nitrate to the auxiliary discharge port. Because of the opening on the inclined guide plate, the porous granular ammonium nitrate on the guide plate flows more easily towards the opening, further preventing residue. Furthermore, under the conveying pressure of the weak airflow, the porous granular ammonium nitrate at the unobstructed opening is thoroughly blown towards the auxiliary discharge port. The axis of the weak air inlet passes through the opening, ensuring a large airflow at the opening to provide sufficient conveying pressure.

[0028] The present invention provides several grooves 24 on the guide plate 2 located in the half-section of the installation groove. Each groove extends from the edge of the guide plate to the opening. Since this half-section is difficult to be blown by strong winds, the grooves facilitate the flow of porous granular ammonium nitrate in this area, ensuring that no residue remains in this area. Preferably, several air holes 21 are provided at the bottom of each groove to prevent porous granular ammonium nitrate from remaining at the bottom of the groove. Several air guide channels 18 are provided on the inner wall of the cavity 1 from the weak air inlet to the installation groove. A notch 25 is provided at the edge of the guide plate corresponding to each air guide channel. Each groove connects to a notch, so that weak air can flow along the air guide channel to the notch, preventing porous granular ammonium nitrate from remaining in the gap between the installation groove and the guide plate.

[0029] Preferably, the top of the outer shell 5 is provided with a cover plate 51 that covers and seals the top of the cavity, the feed hopper 6 is disposed on the cover plate, and the feed inlet is opened on the cover plate; the bottom of the outer shell is provided with a bottom plate 52 that covers and seals the bottom of the cavity, thereby sealing the cavity and partition through the cover plate and the bottom plate, which can improve the sealing performance and prevent heat loss; the weak air inlet is opened on the bottom plate, and the air supply unit includes a strong air supply fan 8 and a weak air inlet fan 9 installed on the bottom plate. The strong air supply fan delivers strong air to the strong air inlet, and the weak air supply fan delivers weak air to the weak air inlet, thereby realizing the classified control of strong and weak air. In the implementation process, the feed hopper 6 is provided with a feed pipe 61. The feed hopper is funnel-shaped, and its lower outlet is connected to the feed inlet, thereby quantitatively conveying porous granular ammonium nitrate into the feed hopper. Under the action of gravity, the porous granular ammonium nitrate flows from the feed inlet into the cavity, realizing quantitative conveying.

[0030] Specifically, the strong air intake fan and the strong air inlet are both located on one side of the cavity. The strong air intake pipe 81 connecting the strong air intake fan and the strong air inlet is tangentially set on the outer wall of the cavity on this side to ensure that the strong air enters the air duct tangentially to achieve the purpose of forming a vortex. The weak air intake fan, the main discharge port, and the auxiliary discharge port are all located on the other side of the cavity. This arrangement provides heat sources on both sides of the cavity, improving the uniformity of preheating. On the other hand, it makes full use of the space of the partition cavity, resulting in a more reasonable layout. The discharge channel 3, tangentially set on the outer wall of the cavity on the other side, is a three-way channel, which helps to balance the layout of the cavity, making air intake and discharge more convenient, thereby increasing the discharge speed and preventing blockage. Two of the three-way channels are connected to the main discharge port and the auxiliary discharge port, respectively, and the third channel is connected to the discharge pipe 31 installed on the outer wall of the outer shell. During implementation, due to the high conveying pressure of the strong wind, a certain negative pressure is formed on the auxiliary discharge port after it enters the discharge channel, which makes the discharge speed of the auxiliary discharge port faster and the discharge smoother, further avoiding material blockage.

[0031] The bottom plate of the present invention has a bottom chamber 10 on its lower side. The weak air inlet pipe 91 connected to the weak air inlet fan passes through the bottom plate and enters the bottom chamber, and then connects to the weak air inlet. This allows the weak air inlet to be tilted relative to the guide plate, ensuring that the axis of the weak air inlet passes through the opening. The bottom of the bottom chamber is open, and a filter screen 53 is installed on it. An air duct 54 is provided inside the bottom chamber. Two ports at one end of the air duct are connected to the air inlets of the strong air inlet fan and the weak air inlet fan, respectively. The other end of the air duct is located above the filter screen. Thus, under the action of the blower unit, external air is filtered and introduced into the cavity through the air duct, improving the purity of the air and ensuring the quality of the porous granular ammonium nitrate. This invention houses the entire pneumatic system within the hopper and outer shell, making full use of waste heat. Furthermore, apart from control valves and pressure gauges, no other components are installed on the outside of the conveyor. This reduces the overall size of the conveyor and the space it occupies, while also minimizing interference with other equipment on the mixing vehicle, further improving safety.

[0032] like Figure 4 , Figure 5 and Figure 6The vortex cone 102 of this invention has a large upper diameter and a small lower diameter. One side of the upper end of the vortex cone is connected to the end of the hose, and the other side of the upper end of the vortex cone is connected to a fuel pipe 103 for conveying fuel for ammonium nitrate explosive. The porous granular ammonium nitrate conveyed by pneumatics generates a vortex in the inner cavity of the vortex cone and initially mixes with the fuel before flowing from the lower end of the vortex cone into the intermediate connector 104, and then from the intermediate connector into the static mixing device 41. During implementation, the upper end of the vortex cone is sealed, and the hose is arranged tangentially to the vortex cone to ensure that the conveyed porous granular ammonium nitrate generates a vortex in the vortex cone, thereby mixing with the fuel conveyed from the upper end. Then, under the action of gravity and wind pressure, the mixture flows from the lower end of the vortex cone into the intermediate connector.

[0033] The static mixing device 41 of the present invention includes an outer pipe 411 connected to the intermediate connector and a mixing unit 412 disposed within the outer pipe. The mixing unit disperses the initially mixed mixture into multiple fluid streams and performs repeated cross-mixing. The mixture flowing into the intermediate connector enters the outer pipe and then flows into the mixing unit. The mixing unit comprises three sections connected in sequence: a front section, a middle section, and a rear section. Each section is formed by several perpendicularly intersecting frames 413 spliced ​​into a grid. The mixture is first dispersed into 12 fluid streams within the grid, and then repeatedly cross-mixed within the grid, thus achieving three-stage mixing and significantly improving the uniformity of the mixture. Preferably, the front, middle, and rear sections are arranged perpendicularly in pairs to change the flow direction of each mixing, disrupting the flow field pattern of the mixture and further improving the uniformity of the mixture.

[0034] During implementation, each grid segment is formed by splicing together two sets of perpendicularly intersecting frames. Each set of frames contains three parallel frames to ensure that the mixture can be dispersed into 12 fluid streams. Preferably, one frame 413 in one set of frames includes a frame 414 formed according to the inner wall of the outer tube and three horizontal bars 415 arranged perpendicular to the frame. Each horizontal bar 415 is perpendicularly connected to the corresponding frame in the other set of frames to form a grid, achieving repeated cross-mixing. The three horizontal bars are connected by two vertically arranged vertical bars 416. The two ends of each vertical bar extend to abut against the inner wall of the outer tube, which not only ensures the stability of the entire mixing unit, but also forms four rows of grid space with the outer tube. Each row is divided into three columns by two vertical bars, thus forming 12 grids, which in turn disperse the mixture into 12 fluid streams, ensuring that the mixture is fully dispersed and further improving the uniformity of mixing. Each horizontal bar is divided into three segments, one of which is connected to the frame, and the other two segments are respectively connected to two vertical bars. Therefore, the vertical bar and a section of the horizontal bar can be set as separate components, and then welded together to form a whole hybrid unit. This hybrid unit is then inserted into the outer tube to complete the installation. The component splicing method is not only convenient for installation and disassembly, but also facilitates cleaning.

[0035] As can be seen from the above, the present invention first preheats the porous granular ammonium nitrate through a conveyor, and then pre-disperses the porous granular ammonium nitrate by pneumatic blowing. Then it is conveyed to the vortex cone tube for initial mixing with fuel, and then repeatedly cross-mixed by a static mixing device. It can be seen that the conveying system of the present invention adopts a three-stage mixing method of pre-dispersion, initial mixing and repeated cross-mixing, which greatly improves the uniformity of explosive mixing and improves the blasting effect. At the same time, the wind pressure also has a preheating effect, which improves the detonation sensitivity.

Claims

1. A continuously operating ammonium nitrate explosive conveying system, comprising two conveyors capable of separately holding porous granular ammonium nitrate, characterized in that: Each conveyor is connected to a flexible hose mounted on the telescopic boom of the MG (Ammonium Nitrate) explosive vehicle. The end of the hose is equipped with a vortex cone, which is connected to a static mixing device. After one conveyor pneumatically delivers porous granular ammonium nitrate into the hose, it switches to another conveyor for pneumatic delivery. The fuel for the MG explosive and the porous granular ammonium nitrate pneumatically delivered by the conveyors are respectively conveyed into the vortex cone for initial vortex mixing before flowing into the static mixing device for repeated cross-mixing. The mixture then converges and flows into the borehole. Each conveyor includes a cylindrical outer casing mounted on the frame of the MG explosive vehicle. The shell contains a conical cavity with a larger diameter at the top and a smaller diameter at the bottom. A feed hopper is located on the upper side of the shell. A partition is formed between the shell and the cavity, and a blower unit is installed within this partition. A discharge channel connected to a flexible hose is also located within the partition. After the porous granular ammonium nitrate from the feed hopper enters the cavity, the heat generated by the blower unit preheats the cavity. Air supplied by the blower unit to the cavity then blows the porous granular ammonium nitrate to the discharge channel, and finally into the flexible hose. The top of the cavity has an opening connecting to the feed hopper. The hopper has a feed inlet, and a strong air inlet is provided on the lower side wall of the cavity. Below the strong air inlet, on the lower side wall of the cavity, there are a main discharge outlet and an auxiliary discharge outlet, both connected to the discharge channel. The inner wall of the cavity has a spiral-shaped air duct, with its upper end connected to the strong air inlet, its middle section connected to the main discharge outlet, and its lower end connected to the auxiliary discharge outlet. A weak air inlet is provided at the bottom of the cavity. After the porous granular ammonium nitrate enters the cavity through the feed inlet, the strong air supplied by the blower unit through the strong air inlet flows along the air duct to form... A swirling flow is used to blow the porous granular ammonium nitrate flowing to the lower part of the cavity downwards to the main discharge port, and then into the discharge channel. The blower unit uses a weak air supply via the weak air inlet to blow the remaining porous granular ammonium nitrate flowing to the bottom of the cavity upwards to the auxiliary discharge port, and then into the discharge channel. An inclined guide plate is provided inside the cavity. The lower end of the guide plate is connected to the auxiliary discharge port, and the higher end is located on the lower side of a corresponding section of the induced draft trough. Several air holes are opened on the guide plate. The weak air blown into the air holes blows the remaining porous granular ammonium nitrate to the auxiliary discharge port.

2. The continuously operating ammonium nitrate explosive delivery system according to claim 1, characterized in that: The inner wall of the cavity is provided with a mounting groove along the circumference. The periphery of the guide plate is arranged in the mounting groove. Half of the mounting groove coincides with a section of the air duct from the auxiliary discharge port to its opposite position. The other half of the mounting groove is symmetrical to the first half. A circular opening is provided on the guide plate near the auxiliary discharge port. Two retaining strips extend from both sides of the opening and are engaged with the auxiliary discharge port. The axis of the weak air inlet passes through the opening. The weak air delivered by the weak air inlet blows towards the opening to blow the residual porous granular ammonium nitrate to the auxiliary discharge port.

3. The continuously operating ammonium nitrate explosive delivery system according to claim 2, characterized in that: The guide plate located in the half section of the mounting groove has several grooves, each groove extending from the edge of the guide plate to the opening, and several air holes are formed at the bottom of each groove; several air guide grooves are formed on the inner wall of the cavity from the weak air inlet to the mounting groove, and a notch is provided on the edge of the guide plate corresponding to each air guide groove, and each groove is connected to a notch.

4. The continuously operating ammonium nitrate explosive delivery system according to claim 1, characterized in that: The top of the outer shell is provided with a cover plate that covers and encloses the top of the cavity, the feed hopper is disposed on the cover plate, and the feed inlet is opened on the cover plate; the bottom of the outer shell is provided with a bottom plate that covers and encloses the bottom of the cavity, the weak air inlet is opened on the bottom plate, and the blower unit includes a strong blower and a weak blower installed on the bottom plate, the strong blower delivers strong air to the strong air inlet, and the weak blower delivers weak air to the weak air inlet.

5. The continuously operating ammonium nitrate explosive delivery system according to any one of claims 1 to 4, characterized in that: The vortex cone has a large diameter at the upper end and a small diameter at the lower end. One side of the upper end of the vortex cone is connected to the end of the hose, and the other side of the upper end of the vortex cone is connected to a fuel pipe for conveying fuel for ammonium nitrate explosive. The porous granular ammonium nitrate conveyed by pneumatics generates a vortex in the inner cavity of the vortex cone and is initially mixed with the fuel before flowing from the lower end of the vortex cone into the intermediate connector, and then from the intermediate connector into the static mixing device.

6. The continuously operating ammonium nitrate explosive delivery system according to claim 5, characterized in that: The static mixing device includes an outer pipe connected to the intermediate joint and a mixing unit disposed within the outer pipe. The mixing unit includes three sections connected in sequence: front, middle and rear. Each section is composed of several frames arranged perpendicularly to form a grid structure. The mixture is first dispersed into multiple streams of fluid by the grid structure, and then repeatedly cross-mixed within the grid structure.

7. The continuously operating ammonium nitrate explosive delivery system according to claim 6, characterized in that: Each segment of the grid structure is composed of two sets of perpendicularly intersecting frames. Each set of frames contains three parallel frames. One frame in one set includes a frame formed along the inner wall of the outer tube and three horizontal bars perpendicular to the frame. Each horizontal bar is perpendicularly connected to the corresponding frame in the other set to form a grid. The three horizontal bars are connected by two vertically arranged vertical bars. The two ends of each vertical bar extend to abut against the inner wall of the outer tube. Each horizontal bar is divided into three segments, one of which is connected to the frame, and the other two segments are respectively connected to the two vertical bars.

Images