A deep-sea cobalt-rich crust milling collection device

Abstract

This invention relates to the field of deep-sea mineral resource mining equipment technology, and discloses a milling-type collection device for deep-sea cobalt-rich crusts. The device includes a deep-sea mining vehicle, inside which is installed a vortex screening and separation component. A buffer and anti-turbidity component is installed on top of the vortex screening and separation component. An adjustable milling collection component is rotatably connected inside the deep-sea mining vehicle. The vortex screening and separation component includes a cylindrical screening barrel, which is located inside the deep-sea mining vehicle. Conical screening barrels are fixedly connected to both ends of the cylindrical screening barrel. This invention utilizes the vortex screening and separation component to create negative pressure and form a spiral vortex, achieving centrifugal separation by utilizing the difference in mass density between ore and sediment. The buffer and anti-turbidity component allows for the slow discharge of sediment, reducing seabed water turbulence. The adjustable milling collection component mills the cobalt-rich crust while flexibly adjusting the elevation angle.

Description

Technical Field

[0001] This invention relates to the field of engineering equipment technology for deep-sea mineral resource mining, specifically a milling-type collection device for deep-sea cobalt-rich crusts. Background Technology

[0002] Deep-sea cobalt-rich crusts are a unique mineral resource widely found on the slopes of seamounts. They are rich in cobalt, nickel, manganese, and various rare earth and platinum group metals. The cobalt content is much higher than that of primary terrestrial cobalt deposits, and the reserves are enormous. The cobalt metal contained in these crusts is a core strategic resource and is widely used in high-tech fields such as aerospace superalloys, new energy batteries, precision catalysis, and laser superconductivity. It is an indispensable key raw material for the development of modern high-end industries and has extremely high development and strategic value.

[0003] Currently, deep-sea cobalt-rich crusts are mostly collected using milling-type collection equipment. The milling structure is used to remove the seabed crust material, and then the mixture of ore and sediment is transported to the mining vessel by negative pressure suction to complete the mining and collection of deep-sea crusts. This is the mainstream operation method for deep-sea mineral mining at present.

[0004] Existing collection equipment lacks a dedicated screening structure. The milled ore and mud mixture cannot be graded and separated on the seabed and can only be screened by onshore equipment. In traditional structures, mud is easily transported along with the ore, resulting in low ore purity and high impurity content. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a milling-type collection device for deep-sea cobalt-rich crusts, which solves the problem that existing devices lack a seabed screening structure, resulting in high impurity content in the ore after milling.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: a milling collection device for deep-sea cobalt-rich crusts, comprising a deep-sea mining vehicle, wherein an eddy current screening and separation component is provided inside the deep-sea mining vehicle, a buffer and anti-turbidity component is installed on the top of the eddy current screening and separation component, and an adjustable milling collection component is rotatably connected inside the deep-sea mining vehicle. The eddy current screening and separation assembly includes a cylindrical screening barrel, which is installed inside a deep-sea mining vehicle. Conical screening barrels are fixedly connected to both the upper and lower ends of the cylindrical screening barrel. A mud and sand guide pipe and a first pipe are fixedly connected to the ends of the two conical screening barrels furthest from the cylindrical screening barrel, respectively. A feed guide hood is fixedly connected to the outside of the cylindrical screening barrel, and the feed guide hood is fixedly connected inside the adjustable milling and collection assembly. Spiral guide plates are fixedly connected inside both the cylindrical and conical screening barrels. A central guide column is fixedly connected inside the conical screening barrel. A slurry conveying pump is fixedly connected to the end of the first pipe furthest from the conical screening barrel, and a second pipe is connected to the output end of the slurry conveying pump.

[0007] Preferably, the buffer and turbidity prevention component includes a pressure regulating and receiving box, which is fixedly connected to the middle of the sediment guide pipe. A pressure-bearing circular plate is slidably connected inside the pressure regulating and receiving box. A top column is fixedly connected to the top of the pressure-bearing circular plate. A return spring is sleeved on the outer periphery of the top column. The return spring is fixedly connected between the pressure regulating and receiving box and the pressure-bearing circular plate. Two rotating shafts are rotatably connected inside the sediment guide pipe. A filter screen is fixedly connected between the two rotating shafts. A traction rope is fixedly connected to the top of the top column. The other end of the traction rope is fixedly connected to the outside of one of the rotating shafts. A shaft end limit seat is fixedly connected to the top of one of the rotating shafts. A spring is fixedly connected to the outside of the other rotating shaft. The other end of the spring is fixedly connected to the outer wall of the sediment guide pipe.

[0008] Preferably, the adjustable milling acquisition component includes a connecting rod rotatably connected to the interior of the deep-sea mining vehicle. An active support roller is fixedly connected to the end of the connecting rod away from the rotating end. A support frame is fixedly connected to the front end of the deep-sea mining vehicle. A driven milling roller is provided on the outer side of the deep-sea mining vehicle. An annular milling belt is sleeved around the outer periphery of the active support roller and the driven milling roller. Multiple sets of cutting heads are fixedly connected to the outer sides of both the annular milling belt and the driven milling roller. A hydraulic rod is installed between the support frame and the annular milling belt.

[0009] Preferably, the fixed housing is fixedly connected to the outer wall of the sediment guide pipe, and the end of the spring away from the rotating shaft is fixedly connected to the inner wall of the fixed housing.

[0010] Preferably, a limiting ring is fixedly connected to the outer side of one of the rotating shafts, and the other end of the traction rope is fixedly connected to the outer side of the rotating shaft and wrapped around the limiting ring. The shaft end limiting seat is located at the top of one of the rotating shafts to form a blocking structure to prevent the traction rope from slipping off from the end of the rotating shaft.

[0011] Preferably, the cutting head is hook-shaped to mill the ore and transport it into the deep-sea mining vehicle.

[0012] Preferably, the fixed end of the hydraulic rod is hinged to the support frame, and the telescopic end of the hydraulic rod is hinged to the inner bracket of the annular milling belt.

[0013] Preferably, the slurry conveying pump is connected to the cone-shaped screening tank located below via the first pipe, and the slurry conveying pump is connected to the conveying pipeline of the marine ore vessel via the second pipe.

[0014] Preferably, the spiral guide plate is spirally arranged along the inner wall of the cylindrical screening barrel and the conical screening barrel, forming a vortex with the central guide column.

[0015] Preferably, the feed guide hood has a square structure and is located below the annular milling belt, for collecting the ore and mud after milling.

[0016] This invention provides a milling-type collection device for deep-sea cobalt-rich crusts. It has the following beneficial effects: 1. This invention features a vortex screening and separation component. A slurry pump provides negative pressure suction, allowing the milled ore and silt mixture to enter a cavity composed of a column and a cone screening barrel. A stable spiral vortex is formed by the cooperation of a spiral guide plate and a central guide column. Centrifugal classification is achieved by utilizing the differences in mass and density between the ore and silt. The heavier ore settles against the inner wall of the cavity and is transported to the ore ship by the pump. The lighter silt flows upward along the central guide column and is discharged, thus achieving automatic separation of ore and sand.

[0017] 2. This invention features an adjustable milling and collection component. Through the cooperation of an active support roller, an annular milling belt, and a driven milling roller, the onboard cutting head rotates as a whole, enabling continuous milling and peeling of cobalt-rich crusts on the seabed, resulting in high collection efficiency. At the same time, the overall milling elevation angle is flexibly adjusted using hydraulic rods and connecting rods to adapt to complex seabed terrain with uneven surfaces. The milling posture is adjusted in real time to avoid excessive milling that would cause a large amount of mud and sand to mix into the ore, thereby improving the purity of ore collection and adaptability to seabed operations.

[0018] 3. This invention incorporates a buffer and anti-turbidity component to slow down the upward flow of silt, allowing it to be slowly discharged through a filter screen. This reduces the impact of direct silt discharge on the seabed, prevents large-scale seabed turbidity currents, and protects the deep-sea ecosystem. Simultaneously, it features an adaptive anti-blockage and unblocking function. When silt accumulates and clogs the pipeline, the accumulated pressure pushes the pressure-bearing circular plate and compresses the reset spring. The traction rope then drives the rotating shaft to rotate and open the filter screen, quickly clearing the blockage. After unblocking, the filter is reset by a combination of the reset spring and the spring-loaded mechanism. Attached Figure Description

[0019] Figure 1 This is a perspective view of the present invention; Figure 2 This is a schematic diagram of the slurry conveying pump of the present invention; Figure 3 This is a schematic diagram of the adjustable milling acquisition component of the present invention; Figure 4 This is a schematic diagram of the structure of the feed guide cover of the present invention; Figure 5 This is a schematic diagram of the structure of the first pipe of the present invention; Figure 6 This is a schematic diagram of the eddy current screening and separation component of the present invention; Figure 7 This is a schematic diagram of the structure of the buffer and anti-turbidity component of the present invention; Figure 8 This is a cross-sectional schematic diagram of the filter screen of the present invention; Figure 9 This is an exploded view of the spring of the present invention.

[0020] The components include: 1. Deep-sea mining vehicle; 2. Buffer and anti-turbidity assembly; 21. Limiting ring; 22. Pressure regulating and receiving box; 23. Pressure-bearing circular plate; 24. Top column; 25. Return spring; 26. Filter screen; 27. Rotating shaft; 28. Traction rope; 29. ​​Clock spring; 210. Shaft end limiting seat; 3. Adjustable milling and collection assembly; 31. Active support roller; 32. Annular milling belt; 33. Cutting head; 34. Driven milling roller; 35. Support frame; 36. Connecting rod; 37. Hydraulic rod; 4. Vortex screening and separation assembly; 41. Columnar screening barrel; 42. Feed guide cover; 43. Slurry conveying pump; 44. Spiral guide plate; 45. Central guide column; 46. First pipe; 47. Second pipe; 48. Conical screening barrel; 49. Sediment guide pipe. Detailed Implementation

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

[0022] Please see the appendix Figure 1 - Appendix Figure 9This invention provides a milling-type collection device for deep-sea cobalt-rich crusts, including a deep-sea mining vehicle 1. The deep-sea mining vehicle 1 is equipped with an eddy current screening and separation component 4. A buffer and anti-turbidity component 2 is installed on the top of the eddy current screening and separation component 4. An adjustable milling collection component 3 is rotatably connected inside the deep-sea mining vehicle 1. The device integrates three core structures: milling collection, eddy current screening, and buffer and anti-turbidity, which work together to realize the milling, screening, conveying, and environmentally friendly sand discharge of deep-sea cobalt-rich crusts, adapting to complex deep-sea mining environments.

[0023] The eddy current screening and separation component 4 includes a cylindrical screening barrel 41, which is installed inside the deep-sea mining vehicle 1. Conical screening barrels 48 are fixedly connected to both the upper and lower ends of the cylindrical screening barrel 41. The ends of the two conical screening barrels 48 furthest from the cylindrical screening barrel 41 are respectively fixedly connected to a mud and sand guide pipe 49 and a first pipe 46. The upper and lower conical screening barrels 48 correspond to the mud and sand discharge and ore conveying channels, respectively, achieving separate treatment of mud and sand and ore without interference. A feed guide hood 42 is fixedly connected to the outside of the cylindrical screening barrel 41. The feed guide hood 42 is fixedly connected inside the adjustable milling and collection component 3, which can accurately collect the mixed material falling off during milling and avoid... To prevent material spillage and waste and ensure centralized screening, both the cylindrical screening barrel 41 and the conical screening barrel 48 are fixedly connected to a spiral guide plate 44. The conical screening barrel 48 is fixedly connected to a central guide column 45. The two work together to form a stable spiral vortex flow field inside the cavity. Centrifugal classification is achieved by utilizing the density and mass difference between ore and silt. The end of the first pipe 46 away from the conical screening barrel 48 is fixedly connected to a slurry conveying pump 43. The output end of the slurry conveying pump 43 is connected to a second pipe 47. The slurry conveying pump 43 provides negative pressure suction power, which completes the suction and screening of the mixed material while stably conveying the separated ore outward.

[0024] Please see the appendix Figure 7 - Appendix Figure 9In a preferred embodiment of the present invention, the buffer and anti-turbidity component 2 includes a pressure regulating and receiving box 22, which is fixedly connected to the middle of the sediment diversion pipe 49. A pressure-bearing circular plate 23 is slidably connected inside the pressure regulating and receiving box 22. A top column 24 is fixedly connected to the top of the pressure-bearing circular plate 23. A return spring 25 is sleeved on the outer periphery of the top column 24. The return spring 25 is fixedly connected between the pressure regulating and receiving box 22 and the pressure-bearing circular plate 23. The return spring 25 can be compressed when sediment accumulates in the pipeline and is under pressure, providing stable elastic support for subsequent structural reset. Two rotating shafts 27 are rotatably connected inside the sediment diversion pipe 49. A filter screen 26 is fixedly connected between the rotating shafts 27. The filter screen 26 can slow down the flow of discharged sediment, reduce the impact of sediment discharge, and prevent the seabed water from becoming turbid. A traction rope 28 is fixedly connected to the top of the top column 24. A shaft end limit seat 210 is fixedly connected to the top of the rotating shaft 27 above the filter screen 26. A spring-loaded spring 29 is fixedly connected to the outside of the rotating shaft 27 below the filter screen 26. The other end of the spring-loaded spring 29 is fixedly connected to the outer wall of the sediment guide pipe 49. The filter screen 26 is automatically rotated to clear blockages by using the pressure of sediment accumulation. The spring-loaded spring 29 is used to achieve automatic reset.

[0025] Please see the appendix Figure 1 - Appendix Figure 3 In a preferred embodiment of the present invention, the adjustable milling acquisition component 3 includes a connecting rod 36, which is rotatably connected to the inside of the deep-sea mining vehicle 1. An active support roller 31 is fixedly connected to the end of the connecting rod 36 away from the rotating end. A support frame 35 is fixedly connected to the front end of the deep-sea mining vehicle 1. A driven milling roller 34 is provided on the outer side of the deep-sea mining vehicle 1. An annular milling belt 32 is sleeved on the outer periphery of the active support roller 31 and the driven milling roller 34. Multiple sets of cutting heads 33 are fixedly connected to the outer sides of both the annular milling belt 32 and the driven milling roller 34. A hydraulic rod 37 is installed between the support frame 35 and the annular milling belt 32. The working elevation angle can be adjusted by extending and retracting the hydraulic rod 37 to adapt to the uneven seabed terrain and reduce the mixing of excess mud and sand during milling.

[0026] Please see the appendix Figure 8 In a preferred embodiment of the present invention, the fixed outer shell is fixedly connected to the outer wall of the sediment guide pipe 49, and the end of the spring spring 29 away from the rotating shaft 27 is fixedly connected to the inner wall of the fixed outer shell. When the rotating shaft 27 rotates to clear the blockage, the spring spring 29 fixedly connected to the lower rotating shaft 27 stores energy. After the blockage is cleared, the spring force is released, which drives the rotating shaft 27 and the filter screen 26 to automatically rotate back to reset and restore the normal sand discharge state.

[0027] Please see the appendix Figure 9In a preferred embodiment of the present invention, a limiting ring 21 is fixedly connected to the outer side of a rotating shaft 27 located at the top of the filter screen 26. The other end of a traction rope 28 is fixedly connected to the outer side of the rotating shaft 27 and wraps around and passes through the limiting ring 21. A shaft end limiting seat 210 is fixed to the top of a rotating shaft 27, which is located above the filter screen 26, forming a blocking structure to prevent the traction rope 28 from slipping off from the end of the rotating shaft 27.

[0028] Please see the appendix Figure 1 - Appendix Figure 3 In a preferred embodiment of the present invention, the cutting head 33 is hook-shaped, which mills the ore and transports it into the deep-sea mining vehicle 1. The hook-shaped cutting head has a better milling effect and can efficiently peel off the seabed crust ore. At the same time, it can also drive the material to gather inward, which is convenient for subsequent screening.

[0029] Please see the appendix Figure 3 In a preferred embodiment of the present invention, the fixed end of the hydraulic rod 37 is hinged to the support frame 35, and the telescopic end of the hydraulic rod 37 is hinged to the inner bracket of the annular milling belt 32.

[0030] Please see the appendix Figure 5 and attached Figure 6 In a preferred embodiment of the present invention, the slurry conveying pump 43 is connected to the cone screening barrel 48 located below through the first pipe 46, and the slurry conveying pump 43 is connected to the conveying pipeline of the ore ship on the sea surface through the second pipe 47, so as to realize the conveying of the screened ore material and complete the ore collection operation.

[0031] Please see the appendix Figure 6 In a preferred embodiment of the present invention, the spiral guide plate 44 is spirally arranged along the inner wall of the cylindrical screening barrel 41 and the conical screening barrel 48, forming a vortex with the central guide column 45.

[0032] Please see the appendix Figure 4 In a preferred embodiment of the present invention, the feed guide cover 42 has a square structure and is located below the annular milling belt 32, for collecting the ore mud and sand after milling.

[0033] Working principle: First, the adjustable milling and collection component 3 enables rapid milling of seabed ore and adapts to different seabed environments. Adjustments can be made to avoid excessive milling of mud and sand on uneven seabeds. Specifically, the motor inside the active support roller 31 drives the annular milling belt 32 to rotate, and the driven milling roller 34 rotates simultaneously. During rotation, the cutting head 33 mills the seabed ore and carries the mixed ore into the support frame 35. When an elevation angle adjustment is needed, the hydraulic rod 37 is activated to raise the milling angle.

[0034] Secondly, the purpose of setting up the vortex screening and separation component 4 is to separate the ore and sand using vortex centrifugal force. The denser and heavier ore will adhere to the edges of the column screening barrel 41 and the cone screening barrel 48, while the lighter ore and sand will flow upwards around the central guide column 45, thus achieving the screening effect. Specifically, the slurry conveying pump 43 starts, drawing in the mixed ore inside the 38 through the first pipe 46, the cone screening barrel 48, the column screening barrel 41, and the feed guide hood 42. When the mixed ore enters the column screening barrel 41, due to the central guide column 45 inside the column screening barrel 41 and the cone screening barrel 48, a spiral vortex is formed along with the seawater. The ore sinks to the bottom and is drawn in by the slurry conveying pump 43, then transported out through the second pipe 47, while the ore and sand will always flow upwards around the central guide column 45. This completes the separation of ore and ore and sand.

[0035] Finally, the buffer and turbidity-prevention component 2 is installed to slowly discharge the sediment, reducing the impact on the seabed and avoiding damage to the seabed ecosystem. Specifically, after the sediment enters the sediment guide pipe 49 from the conical screening barrel 48, it enters a deceleration phase through the filter screen 26 and is slowly discharged from inside the filter screen 26. In the event of sediment blockage, it accumulates inside the sediment guide pipe 49, pushing the pressure plate 23 upward. The return spring 25 contracts, the top column 24 is lifted, and the traction rope 28 is pulled upward. Since the other end of the traction rope 28 is wrapped around the outside of the rotating shaft 27, the rotating shaft 27 will rotate during the pulling action. At this time, the filter screen 26 rotates, and the spring 29 at the bottom accumulates restoring force, allowing the sediment to flow out from the open gap, thus solving the blockage problem. After successful discharge, the return spring 25 pushes the pressure plate 23 downward, and the spring 29, together with the return spring, restores the filter screen 26 to its original position.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A deep-sea cobalt-rich crust milling collection device comprising a deep-sea mining vehicle (1), characterized in that, The deep-sea mining vehicle (1) is equipped with an eddy current screening and separation component (4), and a buffer anti-turbidity component (2) is installed on the top of the eddy current screening and separation component (4). An adjustable milling and collection component (3) is rotatably connected inside the deep-sea mining vehicle (1). The vortex screening and separation assembly (4) includes a cylindrical screening barrel (41), which is located inside the deep-sea mining vehicle (1). Conical screening barrels (48) are fixedly connected to both the upper and lower ends of the cylindrical screening barrel (41). Sediment guide pipes (49) and a first pipe (46) are fixedly connected to the ends of the two conical screening barrels (48) furthest from the cylindrical screening barrel (41), respectively. A feed guide hood (42) is fixedly connected to the outside of the cylindrical screening barrel (41). The material guide cover (42) is fixedly connected inside the adjustable milling collection component (3). The cylindrical screening barrel (41) and the conical screening barrel (48) are both fixedly connected with spiral guide plates (44). The conical screening barrel (48) is fixedly connected with a central guide column (45). The end of the first pipe (46) away from the conical screening barrel (48) is fixedly connected with a slurry conveying pump (43). The output end of the slurry conveying pump (43) is connected with a second pipe (47).

2. A deep-sea cobalt-rich crust milling collection device according to claim 1, characterized in that, The buffer and anti-turbidity component (2) includes a pressure regulating container (22), which is fixedly connected to the middle of the sediment diversion pipe (49). A pressure-bearing circular plate (23) is slidably connected inside the pressure regulating container (22). A top column (24) is fixedly connected to the top of the pressure-bearing circular plate (23). A return spring (25) is sleeved on the outer periphery of the top column (24). The return spring (25) is fixedly connected between the pressure regulating container (22) and the pressure-bearing circular plate (23). The sediment diversion pipe (49) is rotatably connected inside. There are two rotating shafts (27), and a filter screen (26) is fixedly connected between the two rotating shafts (27). A traction rope (28) is fixedly connected to the top of the top column (24). The other end of the traction rope (28) is fixedly connected to the outside of one of the rotating shafts (27). A shaft end limit seat (210) is fixedly connected to the top of one of the rotating shafts (27). A spring spring (29) is fixedly connected to the outside of the other rotating shaft (27). The other end of the spring spring (29) is fixedly connected to the outer wall of the mud and sand guide pipe (49).

3. A deep-sea cobalt-rich crust milling-type collection device according to claim 1, characterized in that, The adjustable milling acquisition component (3) includes a connecting rod (36), which is rotatably connected to the inside of the deep-sea mining vehicle (1). An active support roller (31) is fixedly connected to one end of the connecting rod (36) away from the rotating end. A support frame (35) is fixedly connected to the front end of the deep-sea mining vehicle (1). A driven milling roller (34) is provided on the outside of the deep-sea mining vehicle (1). An annular milling belt (32) is sleeved on the outer periphery of the active support roller (31) and the driven milling roller (34). Multiple sets of cutting heads (33) are fixedly connected to the outer sides of the annular milling belt (32) and the driven milling roller (34). A hydraulic rod (37) is installed between the support frame (35) and the annular milling belt (32).

4. The milling-type collection device for deep-sea cobalt-rich crusts according to claim 2, characterized in that, The fixed housing is fixedly connected to the outer wall of the mud and sand guide pipe (49), and the end of the spring spring (29) away from the rotating shaft (27) is fixedly connected to the inner wall of the fixed housing.

5. The milling-type collection device for deep-sea cobalt-rich crusts according to claim 2, characterized in that, A limiting ring (21) is fixedly connected to the outside of one of the rotating shafts (27), and the other end of the traction rope (28) is fixedly connected to the outside of the rotating shaft (27) and wrapped around the limiting ring (21). The shaft end limiting seat (210) is located at the top of one of the rotating shafts (27) to form a stop structure to prevent the traction rope (28) from slipping off from the end of the rotating shaft (27).

6. A deep sea cobalt-rich crust milling type collecting device according to claim 3, characterized in that, The cutting head (33) is hook-shaped and mills the ore and transports it into the deep-sea mining vehicle (1).

7. A deep sea cobalt-rich crust milling collection device according to claim 6, wherein, The fixed end of the hydraulic rod (37) is hinged to the support frame (35), and the telescopic end of the hydraulic rod (37) is hinged to the inner bracket of the annular milling belt (32).

8. The apparatus of claim 1, wherein, The slurry conveying pump (43) is connected to the cone screening barrel (48) located below through the first pipe (46), and the slurry conveying pump (43) is connected to the sea surface ore transport pipeline through the second pipe (47).

9. The apparatus of claim 1, wherein, The spiral guide plate (44) is spirally arranged along the inner wall of the cylindrical screening barrel (41) and the conical screening barrel (48), forming a vortex with the central guide column (45).

10. A milling-type collection device for deep-sea cobalt-rich crusts according to claim 3, characterized in that, The feed guide hood (42) has a square structure and is located below the annular milling belt (32) for collecting the ore mud and sand after milling.

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