Method and device for fixing lead of physico-chemical combined modified sisal fiber reinforced filling body

Abstract

The invention discloses a method and a device for fixing lead of a physico-chemical combined modified sisal fiber reinforced filling body, and belongs to the technical field of tailing treatment. The invention relates to a lead fixation method for a physico-chemical combined modified sisal fiber reinforced filling body. The method comprises the following steps: S1, physical pretreatment of sisal fibers; s2, performing alkaline leaching pretreatment on the sisal fibers; s3, modifying and pretreating the sisal fibers; s4, the low-concentration full-tailing mortar is prepared into high-concentration full-tailing mortar; s5, mixing and stirring the modified sisal fibers obtained in the step S3 with high-concentration all-tailing mortar, Portland cement and industrial water to form homogeneous filling slurry; the sisal fibers are subjected to physical and chemical combined pretreatment and are added into the filling slurry under the condition of low cement consumption, so that the mechanical property and the lead fixing capacity of a filling body are improved, the influence of migration of heavy metal lead in a well on the environment is prevented, and the problem of tailing stockpiling is reduced to a certain extent.

Description

Technical Field

[0001] The invention relates to the technical field of tailings treatment, and in particular to a method and a device for fixing lead of a physicochemically combined modified sisal fiber reinforced filling body. Background Art

[0002] The storage of tailings is a worldwide problem. Its existence not only occupies a large amount of land, but also poses the risk of dam breach. The most important point is that the surface of tailings contains a large amount of active heavy metal ions. After a long period of large-scale storage and the erosion of rainwater, the heavy metal ions in the tailings pond will flow to the surrounding farmland or groundwater sources, thereby causing heavy metal pollution and causing great harm to humans and the environment. Therefore, the treatment of tailings should meet the requirements of economic savings and environmental safety. Against this background, the inventor proposes a method for fixation of lead in a physicochemically combined modified sisal fiber reinforced filling body.

[0003] Sisal fiber is a natural plant bast fiber, a renewable resource with low price and wide sources. Its use in underground filling systems meets the development concept of energy conservation and environmental protection. At present, sisal fiber has been widely used in composite materials to strengthen concrete; modified sisal fiber can also be used in sewage treatment, but it is still rarely used in the field of underground filling and fixing heavy metal. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the prior art and to propose a method and device for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for lead fixation of a physical-chemical combined modified sisal fiber reinforced filling body comprises the following steps:

[0007] S1. Physical pretreatment of sisal fiber: put the fiber into a mixing drum to clean and remove surface impurities, then dry it at 120°C, and then crush the fiber into small pieces of about 2 cm for standby use;

[0008] S2. Sisal fiber alkali soaking pretreatment: The crushed sisal fiber is placed in a 15% concentration NaOH solution stirring drum and soaked for 3 to 4 hours to dissolve the hemicellulose and lignin in the sisal fiber and destroy the cellulose molecular structure. The fiber needs to be stirred during soaking so that the lignin and hemicellulose in the fiber can be fully destroyed. The stirring speed is 30r / min. After the alkali soaking is completed, it is washed with clean water;

[0009] S3, sisal fiber modification pretreatment: the sisal fiber after alkali soaking is placed in 10% C 2 H 3 C1O 2The solution was immersed in a mixing drum for 24 hours to 2 H 3 C1O 2 The carboxyl groups in the solution are grafted onto the damaged cellulose molecules to enhance the fixation capacity of heavy metal lead; in order to make the carboxyl functional groups grafted onto the cellulose molecules as much as possible, the solution is stirred at a constant speed of 30r / min during the soaking process, thereby preparing the modified sisal fiber; after the soaking is completed, the fiber is directly dried for standby use without washing;

[0010] S4. The whole tailings slurry with a mass concentration of 10% to 15% from the lead-zinc ore concentrator is pumped to a thickening device such as a deep cone thickener or a vertical sand bin through a slurry pump to form a high-concentration whole tailings slurry with a concentration of about 73% to 75%;

[0011] S5, conveying the modified sisal fiber obtained in step S3 to a mixing barrel through a belt conveyor as an additive; pumping the high-concentration full tailings slurry in step S4 to a mixing barrel through a slurry pump as a filling aggregate; conveying the PO425 silicate cement in the cementitious material bin to the mixing barrel through a screw conveyor; conveying the industrial water in the water bin to the mixing barrel through a clean water pump; stirring at a uniform speed in the mixing barrel for 10 to 20 minutes to form a homogeneous filling slurry with a concentration of 61% to 65%;

[0012] S6, transporting the above homogeneous filling slurry to the underground goaf by means of pumping or gravity;

[0013] S7. After curing for 7d, 14d and 28d underground, the in-situ filling body is drilled and cored. After being processed into standard specimens, the original filling body is subjected to a uniaxial compressive strength test according to the procedure described in GB / T51450-2022; then, the in-situ filling body is subjected to a toxicity leaching test according to the procedure described in HJ557-2010.

[0014] Preferably, in the homogenous filling slurry concentration in step S5, the number of whole tailings is 60 parts, the number of cement is 10 parts, and the number of modified sisal fibers is 1-2 parts.

[0015] Preferably, the main chemical components of the whole tailings of the lead-zinc ore in step S4 are: Al2O3, SiO2, FeS2; and its particle size distribution is D03=1.474μm, D06=2.521μm, D30=9.570μm, D70=74.53μm, D97=253.4μm.

[0016] A device for fixing lead of a physicochemically combined modified sisal fiber reinforced filling body, including a mixing drum in a physicochemically combined modified sisal fiber reinforced filling body lead fixing method, the mixing drums in steps S1, S2 and S3 have the same structure, all including a barrel, a rotating tube rotatably connected to the barrel, a plurality of stirring blades fixed at the bottom of the rotating tube, a rotating rod rotatably connected to the barrel, and a stirring motor fixed at the bottom of the barrel and used for driving the rotating rod to rotate.

[0017] Preferably, a connecting tube rotatably connected to the rotating tube is fixedly provided in the cylinder body, a lifting plate is slidably connected between the connecting tube and the rotating rod, a material conveying shell is fixedly provided on the top of the connecting tube, a lifting assembly for lifting the lifting plate is provided on the material conveying shell, a material discharging shell is connected to the top of the material conveying shell, a pushing assembly for pushing the material dropped from the material discharging shell into the material conveying shell is provided in the material conveying shell, and the lifting assembly is connected to the pushing assembly.

[0018] Preferably, the lifting assembly includes a support fixed on the feed shell, the support is rotatably connected to a first rotating rod and a second rotating rod, the first rotating rod is provided with a first gear, the second rotating rod is provided with a second gear meshing with the first gear, the second rotating rod is provided with a second drum, the second drum is wrapped with a second pull rope, the end of the second pull rope away from the second drum passes through the feed shell and the connecting pipe and is fixedly connected to the lifting plate, the feed shell is also fixedly provided with a winding motor for driving the first rotating rod to rotate through the support plate, the first rotating rod is provided with a first drum, the first drum is wrapped with a first pull rope, the end of the first pull rope away from the first drum passes through the feed shell and is connected to the pushing assembly.

[0019] Preferably, the outer ring teeth of the first gear are provided with a vacant portion, and the first gear is intermittently meshed with the second gear.

[0020] Preferably, the pushing assembly includes a sliding plate which is slidably connected in the feed shell and connected to the first pull rope, a first elastic element is arranged between the sliding plate and the inner wall of the feed shell, a second elastic element is fixedly arranged on the side of the sliding plate which is away from the first elastic element, a pushing seat is connected to the end of the second elastic element which is away from the sliding plate, the pushing seat is slidably connected in the feed shell, a recessed hole which is connected to the connecting pipe is provided on the pushing seat, and a baffle for covering the bottom opening of the discharge shell is fixedly arranged on the pushing seat.

[0021] Preferably, the connecting pipe is provided with a first pneumatic elastic telescopic tube which is movably opposed to the lifting plate, a second pneumatic elastic telescopic tube is fixedly provided at the bottom of the conveying shell, an air pipe is connected between the first pneumatic elastic telescopic tube and the second pneumatic elastic telescopic tube, and the baffle is provided with two positioning grooves which are plugged into the second pneumatic elastic telescopic tube.

[0022] Preferably, the first pneumatic elastic telescopic tube and the second pneumatic elastic telescopic tube have the same structure, both comprising a sleeve, a piston slidably connected in the sleeve, a third elastic element arranged between the piston and the inner wall of the sleeve, and a movable rod fixed on the piston. The movable rod of the first pneumatic elastic telescopic tube is provided with an arc surface at the end portion, and the arc surface is movably abutted against the lifting plate. The movable rod of the second pneumatic elastic telescopic tube comprises an elastic telescopic rod fixedly connected to the piston and a positioning rod body fixedly connected to the elastic telescopic rod. The positioning rod body is movably inserted in the positioning groove and movably abuts against the sliding plate. A first inclined surface and a second inclined surface are respectively provided on two sides of the positioning rod body, and the cross-sectional length of the first inclined surface is greater than the cross-sectional length of the second inclined surface.

[0023] Compared with the prior art, the present invention provides a method and device for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body, which has the following beneficial effects:

[0024] 1. The method and device for fixing lead in a filler body reinforced with modified sisal fiber by physical and chemical treatment increases the porosity of the sisal fiber surface, destroys the cellulose molecules, grafts functional groups such as carboxyl groups, and increases the fixation sites for heavy metal lead by physically and chemically treating natural sisal fiber. After the modified sisal fiber is added to the filler slurry and transported to underground filling, the mechanical strength of the filler body can be improved, and the heavy metal lead in the slurry can be fixed to prevent the migration of heavy metal lead underground and affect the environment, thereby reducing the storage problem of tailings to a certain extent.

[0025] 2. The method and device for fixing lead of the physical and chemical combined modified sisal fiber reinforced filling body realizes automatic feeding of the modified sisal fiber material while taking out the sisal fiber material in the mixing drum, thereby improving the automation of material feeding and discharging, shortening the operation time, and thus improving the sisal fiber modification processing efficiency.

[0026] 3. The method and device for fixing lead of the physical and chemical combined modified sisal fiber reinforced filling body, when the lifting plate pushes up the sisal fiber material in the cylinder, the intermittent meshing of the first gear and the second gear causes the lifting plate to intermittently swing downward during the upward movement, thereby accelerating the dehydration effect of the sisal fiber material removed from the cylinder, facilitating the subsequent rapid drying treatment, and further improving the sisal fiber modification processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a flow chart of the steps of the present invention;

[0028] Figure 2 It is a schematic diagram of the external structure of the mixing drum of the present invention;

[0029] Figure 3 For the present invention Figure 2 A partial enlarged structural diagram of the middle part;

[0030] Figure 4 It is a schematic diagram of the cross-sectional structure of the mixing drum of the present invention;

[0031] Figure 5 For the present invention Figure 4 A schematic diagram of the partially enlarged structure of the middle B part;

[0032] Figure 6 It is a structural schematic diagram of the pusher seat and the baffle of the present invention;

[0033] Figure 7 It is a schematic structural diagram of the second pneumatic elastic telescopic rod of the present invention when no force is applied to the material conveying shell.

[0034] In the figure: 1, mixing drum; 101, drum body; 102, rotating tube; 103, stirring blade; 104, rotating rod; 105, stirring motor; 2, connecting pipe; 3, lifting plate; 4, feeding shell; 5, discharging shell; 6, support; 601, first rotating rod; 6011, first gear; 6012, first reel; 6013, first pull rope; 602, second rotating rod; 6021, second gear; 6022, second reel; 6023, second pull rope; 603, reeling motor ; 7. Vacant part; 8. Sliding plate; 801. First elastic element; 802. Second elastic element; 803. Pushing seat; 8031. Concave hole; 8032. Baffle; 9. First pneumatic elastic telescopic tube; 901. Sleeve; 902. Piston; 903. Third elastic element; 904. Movable rod; 9041. Elastic telescopic rod; 9042. Positioning rod body; 9043. First inclined plane; 9044. Second inclined plane; 10. Second pneumatic elastic telescopic tube; 11. Positioning groove. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0036] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0037] Example 1: Reference Figure 1-7 A method for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body comprises the following steps:

[0038] S1, physical pretreatment of sisal fiber: put the fiber into a mixing drum 1 to clean and remove surface impurities, then dry it at 120°, and then crush the fiber into small pieces of about 2 cm for standby use;

[0039] S2, sisal fiber alkali soaking pretreatment: the crushed sisal fiber is placed in a 15% concentration NaOH solution mixing drum 1 and soaked for 3 to 4 hours to dissolve the hemicellulose and lignin in the sisal fiber and destroy the cellulose molecular structure. The fiber needs to be stirred during soaking so that the lignin and hemicellulose in the fiber can be fully destroyed. The stirring speed is 30r / min. After the alkali soaking is completed, it is washed with clean water;

[0040] S3, sisal fiber modification pretreatment: the sisal fiber after alkali soaking is placed in 10% C 2 H 3 C1O 2 The solution is immersed in the mixing cylinder 1 for 24 hours, the purpose of which is to 2 H 3 C1O 2 The carboxyl groups in the solution are grafted onto the damaged cellulose molecules to enhance the fixation capacity of heavy metal lead; in order to make the carboxyl functional groups grafted onto the cellulose molecules as much as possible, the solution is stirred at a constant speed of 30r / min during the soaking process, thereby preparing the modified sisal fiber; after the soaking is completed, the fiber is directly dried for standby use without washing;

[0041] S4. The whole tailings slurry with a mass concentration of 10% to 15% from the lead-zinc ore concentrator is pumped to a thickening device such as a deep cone thickener or a vertical sand bin through a slurry pump to form a high-concentration whole tailings slurry with a concentration of about 73% to 75%;

[0042] S5, conveying the modified sisal fiber obtained in step S3 to a mixing barrel through a belt conveyor as an additive; pumping the high-concentration full tailings slurry in step S4 to a mixing barrel through a slurry pump as a filling aggregate; conveying the PO425 silicate cement in the cementitious material bin to the mixing barrel through a screw conveyor; conveying the industrial water in the water bin to the mixing barrel through a clean water pump; stirring at a uniform speed in the mixing barrel for 10 to 20 minutes to form a homogeneous filling slurry with a concentration of 61% to 65%;

[0043] S6, transporting the above homogeneous filling slurry to the underground goaf by means of pumping or gravity;

[0044] S7. After solidification for 7d, 14d and 28d underground, the in-situ filling body is drilled and cored, and processed into standard specimens. Drill three times at each age, and make three groups of filling body test blocks in each borehole, totaling nine groups of filling body test blocks. The average value is taken as the compressive strength of the filling body at that age. The in-situ filling body is subjected to a uniaxial compressive strength test according to the procedure described in GB / T51450-2022; then, the in-situ filling body is subjected to a toxic leaching test according to the procedure described in HJ557-2010.

[0045] The present application increases the porosity of the sisal fiber surface, destroys the cellulose molecules, grafts functional groups such as carboxyl groups, and increases the fixing sites for heavy metal lead by subjecting natural sisal fibers to physical and chemical treatments; after the modified sisal fibers are added to the filling slurry and transported to underground filling, the mechanical strength of the filling body can be improved, and the heavy metal lead in the slurry can be fixed, preventing the migration of the heavy metal lead underground from affecting the environment, thereby reducing the problem of tailings storage to a certain extent.

[0046] As a preferred technical solution of the present invention, further, in step S5, the concentration of the homogenized filling slurry includes 60 parts of whole tailings, 10 parts of ordinary Portland cement, 1 to 2 parts of modified sisal fiber, and a mass concentration of the filling slurry of 72%.

[0047] As a preferred technical solution of the present invention, further, the main chemical components of the whole lead-zinc ore tailings in step S4 are: Al2O3, SiO2, FeS2, etc.; its particle size distribution is D03=1.474μm, D06=2.521μm, D30=9.570μm, D70=74.53μm, D97=253.4μm.

[0048] Example 2: Reference Figure 1-7 A device for fixing lead of a physical and chemical combined modified sisal fiber reinforced filler, including a mixing drum 1 in a method for fixing lead of a physical and chemical combined modified sisal fiber reinforced filler, the mixing drum 1 in steps S1, S2 and S3 has the same structure, including a barrel 101, a rotating tube 102 rotatably connected to the barrel 101, a plurality of stirring blades 103 fixed at the bottom of the rotating tube 102, a rotating rod 104 rotatably connected to the barrel 101, and a stirring motor 105 fixed at the bottom of the barrel 101 and used to drive the rotating rod 104 to rotate; specifically, when the mixing drum 1 performs a stirring operation, the stirring motor 105 is controlled to run, so that the output shaft of the stirring motor 105 drives the rotating rod 104 to rotate, and the rotating rod 104 drives the stirring blade 103 to rotate through the rotating tube 102, so that the stirring blade 103 drives the materials in the barrel 101 to rotate and mix.

[0049] As a preferred technical solution of the present invention, further, a connecting tube 2 rotatably connected to the rotating tube 102 is fixedly provided in the cylinder 101, a lifting plate 3 is slidably connected between the connecting tube 2 and the rotating rod 104, a feed shell 4 is fixedly provided on the top of the connecting tube 2, a lifting assembly for lifting the lifting plate 3 is provided on the feed shell 4, a discharge shell 5 is connected to the top of the feed shell 4, a pushing assembly for pushing the material dropped from the discharge shell 5 into the feed shell 4 is provided in the feed shell 4, and the lifting assembly is connected to the pushing assembly.

[0050] Furthermore, the lifting assembly includes a support 6 fixedly mounted on the feed shell 4, and a first rotating rod 601 and a second rotating rod 602 are rotatably connected to the support 6, a first gear 6011 is provided on the first rotating rod 601, a second gear 6021 meshing with the first gear 6011 is provided on the second rotating rod 602, a second reel 6022 is provided on the second rotating rod 602, a second pull rope 6023 is wound around the second reel 6022, an end of the second pull rope 6023 away from the second reel 6022 passes through the feed shell 4 and the connecting pipe 2 and is fixedly connected to the lifting plate 3, the feed shell 4 is also fixedly provided with a winding motor 603 for driving the first rotating rod 601 to rotate through the support plate, a first reel 601 is provided on the first rotating rod 601, a first pull rope 6013 is wound around the first reel 6012, and an end of the first pull rope 6013 away from the first reel 6012 passes through the feed shell 4 and is connected to the pushing assembly.

[0051] Furthermore, the outer ring teeth of the first gear 6011 are provided with a vacant portion 7 , and the first gear 6011 is intermittently meshed with the second gear 6021 .

[0052] Furthermore, the pushing assembly includes a sliding plate 8 which is slidably connected in the feed shell 4 and connected to the first pull rope 6013, a first elastic element 801 is arranged between the sliding plate 8 and the inner wall of the feed shell 4, a second elastic element 802 is fixedly arranged on the side of the sliding plate 8 which is away from the first elastic element 801, and a pushing seat 803 is connected to the end of the second elastic element 802 which is away from the sliding plate 8, the pushing seat 803 is slidably connected in the feed shell 4, a recessed hole 8031 ​​which is connected to the connecting pipe 2 is provided on the pushing seat 803, and a baffle 8032 for covering the bottom opening of the discharge shell 5 is fixedly arranged on the pushing seat 803.

[0053] Furthermore, a first pneumatic elastic telescopic tube 9 is provided on the connecting tube 2 and is movably opposed to the lifting plate 3. A second pneumatic elastic telescopic tube 10 is fixedly provided at the bottom of the conveying shell 4. An air pipe is connected between the first pneumatic elastic telescopic tube 9 and the second pneumatic elastic telescopic tube 10. Two positioning grooves 11 for plugging with the second pneumatic elastic telescopic tube 10 are provided on the baffle 8032.

[0054] Furthermore, the first pneumatic elastic telescopic tube 9 and the second pneumatic elastic telescopic tube 10 have the same structure, both including a sleeve 901, a piston 902 slidably connected in the sleeve 901, a third elastic element 903 arranged between the piston 902 and the inner wall of the sleeve 901, and a movable rod 904 fixed on the piston 902. The end of the movable rod 904 of the first pneumatic elastic telescopic tube 9 is provided with an arc surface, and the arc surface is movably abutted against the lifting plate 3. The movable rod 904 of the second pneumatic elastic telescopic tube 10 includes an elastic telescopic rod 9041 fixedly connected to the piston 902 and a positioning rod body 9042 fixedly connected to the elastic telescopic rod 9041. The positioning rod body 9042 is movably inserted in the positioning groove 11 and movably abuts against the sliding plate 8. The two sides of the positioning rod body 9042 are respectively provided with a first inclined surface 9043 and a second inclined surface 9044, and the cross-sectional length of the first inclined surface 9043 is greater than the cross-sectional length of the second inclined surface 9044.

[0055] Specifically, after the sisal fibers in the mixing drum 1 are mixed and modified, the winding motor 603 is controlled to run, and the output shaft of the winding motor 603 drives the first rotating rod 601 to rotate, and the first gear 6011 on the first rotating rod 601 is meshed with the second gear 6021 on the second rotating rod 602 for transmission, so that the first rotating rod 601 drives the second rotating rod 602 to rotate, and when the first rotating rod 601 rotates, the first pull rope 6013 is wound by the first reel 6012, and the first pull rope 6013 pulls the sliding plate 8, and the sliding plate 8 moves transversely in the feeding shell 4, and the first elastic element 801 is stretched. At this time, the movable rod 904 of the second pneumatic elastic telescopic tube 10 is plugged into the baffle 8032 to fix the pushing seat 803 in place, and as the sliding plate 8 moves, the second elastic element 802 is stretched, and the second rotating rod 6 When 02 rotates, the second pull rope 6023 is wound up by the second reel 6022, and the second pull rope 6023 pulls up the lifting plate 3, so that the lifting plate 3 drives all the sisal fiber materials in the cylinder 101 to move upward, so as to avoid incomplete discharge of the sisal fiber materials when the cylinder 101 is discharged. Since the first gear 6011 is provided with a vacant portion 7, the first gear 6011 is intermittently meshed with the second gear 6021. When the first gear 6011 is not meshed with the second gear 6021, the lifting plate 3 moves downward under the action of gravity, and then continues to move upward under the meshing between the gears, so that the lifting plate 3 drives the sisal fiber materials to shake during the rising period, thereby accelerating the dehydration effect of the sisal fiber materials removed from the cylinder 101, facilitating the subsequent rapid drying thereof, and improving the efficiency of the sisal fiber modification processing;

[0056] As the winding motor 603 continues to run, the sliding plate 8 moves to the movable rod 904 of the second pneumatic elastic telescopic tube 10, the sliding plate 8 abuts against the second inclined surface 9044, the positioning rod body 9042 is forced to squeeze the elastic telescopic rod 9041, and the second inclined surface 9044 of the positioning rod body 9042 enters the positioning groove 11. At this time, the top surface of the lifting plate 3 and the inner wall surface of the feed shell 4 are on the same side, the winding motor 603 is controlled to stop running, and the sisal fiber material is placed between the top inner wall of the feed shell 4 and the lifting plate 3. The lifting plate 3 can also cooperate with the inner wall of the feed shell 4 to squeeze the excess moisture in the sisal material fiber. After the curved surface on one side of the second inclined surface 9044 of the positioning rod body 9042 leaves the positioning groove 11, the inner wall of the positioning groove 11 can be pushed by the second elastic element 802. The second inclined surface 9044 of the positioning rod body 9042 continues to exert force, and the positioning rod body 9042 avoids the baffle 8032. The baffle 8032 is no longer restricted and moves horizontally with the pushing seat 803. The pushing seat 803 can push the material between the lifting plate 3 and the inner wall of the feeding shell 4, and at the same time, it can transport the material that falls into the concave hole 8031 ​​of the pushing seat 803 in the discharge shell 5 to the upper side of the lifting plate 3. At this time, the second positioning groove 11 of the baffle 8032 is placed on the upper side of the positioning rod body 9042. The positioning rod body 9042 is inserted into the second positioning groove 11 of the baffle 8032 under the push of the elastic telescopic rod 9041. The curved surface on one side of the first inclined surface 9043 of the positioning rod body 9042 abuts against the inner wall of the positioning groove 11, and the position of the baffle 8032 is limited at this time.

[0057] Then, the output shaft of the winding motor 603 is controlled to rotate in the opposite direction, and the first pull rope 6013 no longer applies force to the sliding plate 8. The sliding plate 8 is reset under the pull of the stretched first elastic element 801, and the second elastic element 802 is stretched. The second pull rope 6023 no longer applies force to the lifting plate 3. The lifting plate 3 moves downward under the action of its own gravity, and the sisal fiber material to be modified moves downward synchronously and falls into the cylinder 101. After the lifting plate 3 drops to a certain height, the lifting plate 3 abuts against the movable rod 904 of the first pneumatic elastic telescopic tube 9, and the movable rod 904 is forced to move toward the first When the pneumatic elastic telescopic tube 9 contracts, the air in the first pneumatic elastic telescopic tube 9 is guided to the second pneumatic elastic telescopic tube 10 through the air pipe, and the piston 902 of the second pneumatic elastic telescopic tube 10 is forced to move downward, and the piston 902 drives the positioning rod body 9042 to move downward through the elastic telescopic rod 9041, so that the curved surface of the positioning rod body 9042 leaves the positioning groove 11, and then the baffle 8032 drives the push seat 803 to reset under the action of the stretched second elastic element 802, so that the concave hole 8031 ​​of the push seat 803 re-receives the sisal fiber material to be modified that falls in the discharge shell 5.

[0058] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for lead fixation of a physical and chemically combined modified sisal fiber reinforced filling body, characterized in that: The following steps are involved: S1, physical pretreatment of sisal fiber: the fiber is placed in a mixing drum (1) to clean and remove surface impurities, and then high-temperature drying is performed at 120°, and then the fiber is crushed into small pieces of about 2 cm for standby use; S2. Alkali soaking pretreatment of sisal fiber: the crushed sisal fiber is placed in a 15% concentration NaOH solution stirring drum (1) and soaked for 3-4 hours to dissolve hemicellulose and lignin in the sisal fiber and destroy the cellulose molecular structure. Stirring is required during soaking to fully destroy the lignin and hemicellulose in the fiber. The stirring speed is 30r / min. After the alkali soaking is completed, the fiber is washed with clean water; S3, sisal fiber modification pretreatment: the sisal fiber after alkali soaking is placed in a 10% C2H3ClO2 solution stirring drum (1) and soaked for 24 hours, the purpose of which is to graft the carboxyl groups in the C2H3ClO2 solution onto the damaged cellulose molecules to enhance the fixation capacity of heavy metal lead; in order to make the carboxyl functional groups grafted onto the cellulose molecules as much as possible, stirring at a constant speed of 30r / min during the soaking process, thereby preparing modified sisal fiber; after soaking, it is not washed but directly dried for standby use; S4. The whole tailings slurry with a mass concentration of 10% to 15% from the lead-zinc ore concentrator is pumped to a thickening device such as a deep cone thickener or a vertical sand bin through a slurry pump to form a high-concentration whole tailings slurry with a concentration of about 73% to 75%; S5, conveying the modified sisal fiber obtained in step S3 to a mixing barrel through a belt conveyor as an additive; pumping the high-concentration full tailings slurry in step S4 to a mixing barrel through a slurry pump as a filling aggregate; conveying the PO425 silicate cement in the cementitious material bin to the mixing barrel through a screw conveyor; conveying the industrial water in the water bin to the mixing barrel through a clean water pump; stirring at a uniform speed in the mixing barrel for 10 to 20 minutes to form a homogeneous filling slurry with a concentration of 61% to 65%; S6, transporting the above homogeneous filling slurry to the underground goaf by means of pumping or gravity; S7. After curing for 7d, 14d and 28d underground, the in-situ filling body is drilled and cored. After being processed into standard specimens, the original filling body is subjected to a uniaxial compressive strength test according to the procedure described in GB / T51450-2022; then, the in-situ filling body is subjected to a toxicity leaching test according to the procedure described in HJ557-2010.

2. The method for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body according to claim 1, characterized in that: In the homogenous filling slurry in step S5, the proportion of whole tailings is 60 parts, the proportion of cement is 10 parts, and the proportion of modified sisal fiber is 1-2 parts.

3. The method for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body according to claim 1, characterized in that: The main chemical components of the whole lead-zinc ore tailings in step S4 are: Al2O3, SiO2, FeS2; Its particle size distribution is D03=1.474μm, D06=2.521μm, D30=9.570μm, D70=74.53μm, D97=253.4μm.

4. A device for fixing lead of a physicochemically combined modified sisal fiber reinforced filling body, comprising the mixing drum (1) in the method for fixing lead of a physicochemically combined modified sisal fiber reinforced filling body according to claim 1, characterized in that: The stirring drum (1) in steps S1, S2 and S3 has the same structure, and comprises a drum body (101), a rotating tube (102) rotatably connected to the drum body (101), a plurality of stirring blades (103) fixedly arranged at the bottom of the rotating tube (102), a rotating rod (104) rotatably connected to the drum body (101), and a stirring motor (105) fixedly arranged at the bottom of the drum body (101) and used for driving the rotating rod (104) to rotate.

5. The device for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body according to claim 4 is characterized in that: A connecting tube (2) is fixedly provided in the cylinder (101) and is rotatably connected to the rotating tube (102); a lifting plate (3) is slidably connected between the connecting tube (2) and the rotating rod (104); a material conveying shell (4) is fixedly provided on the top of the connecting tube (2); a lifting component for lifting the lifting plate (3) is provided on the material conveying shell (4); a material discharge shell (5) is connected to the top of the material conveying shell (4); a material pushing component for pushing the material discharged from the material discharge shell (5) and dropped into the material conveying shell (4) is provided in the material conveying shell (4); and the lifting component is connected to the material pushing component.

6. The device for lead fixation of a physical-chemical combined modified sisal fiber reinforced filling body according to claim 5, characterized in that: The lifting assembly comprises a support (6) fixed on the material conveying shell (4), the support (6) is rotatably connected to a first rotating rod (601) and a second rotating rod (602), the first rotating rod (601) is provided with a first gear (6011), the second rotating rod (602) is provided with a second gear (6021) meshing with the first gear (6011), the second rotating rod (602) is provided with a second reel (6022), the second reel (6022) is wound with a second pull rope (6023), and the second pull rope (6023) is connected to the second reel (6022). The end of the conveying shell (4) (6023) away from the second reel (6022) passes through the conveying shell (4) and the connecting pipe (2) and is fixedly connected to the lifting plate (3); the conveying shell (4) is also fixedly provided with a winding motor (603) for driving the first rotating rod (601) to rotate through a support plate; the first rotating rod (601) is provided with a first reel (6012); the first reel (6012) is wound with a first pull rope (6013); the end of the first pull rope (6013) away from the first reel (6012) passes through the conveying shell (4) and is connected to the pushing assembly.

7. The device for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body according to claim 6, characterized in that: The outer ring teeth of the first gear (6011) are provided with a vacant portion (7), and the first gear (6011) is intermittently meshed with the second gear (6021).

8. The device for lead fixation of a physical-chemical combined modified sisal fiber reinforced filling body according to claim 7, characterized in that: The push assembly comprises a sliding plate (8) which is slidably connected in the feed shell (4) and connected to the first pull rope (6013); a first elastic element (801) is arranged between the sliding plate (8) and the inner wall of the feed shell (4); a second elastic element (802) is fixedly arranged on the side of the sliding plate (8) away from the first elastic element (801); an end of the second elastic element (802) away from the sliding plate (8) is connected to a push seat (803); the push seat (803) is slidably connected in the feed shell (4); a concave hole (8031) which is connected to the connecting pipe (2) is provided on the push seat (803); and a baffle (8032) for covering the bottom opening of the discharge shell (5) is fixedly arranged on the push seat (803).

9. The device for lead fixation of a physical-chemical combined modified sisal fiber reinforced filling body according to claim 8, characterized in that: The connecting pipe (2) is provided with a first pneumatic elastic telescopic tube (9) that is movably opposed to the lifting plate (3); a second pneumatic elastic telescopic tube (10) is fixedly provided at the bottom of the conveying shell (4); an air pipe is connected between the first pneumatic elastic telescopic tube (9) and the second pneumatic elastic telescopic tube (10); and the baffle (8032) is provided with two positioning grooves (11) that are plugged into the second pneumatic elastic telescopic tube (10).

10. The device for lead fixation of a physical and chemical combined modified sisal fiber reinforced filling body according to claim 9, characterized in that: The first pneumatic elastic telescopic tube (9) and the second pneumatic elastic telescopic tube (10) have the same structure, and both comprise a sleeve (901), a piston (902) slidably connected to the sleeve (901), a third elastic element (903) arranged between the piston (902) and the inner wall of the sleeve (901), and a movable rod (904) fixed to the piston (902). The movable rod (904) of the first pneumatic elastic telescopic tube (9) has an arc surface at its end, and the arc surface is movably abutted against the lifting plate (3). The second pneumatic elastic telescopic tube (9) is The movable rod (904) of the retractable tube (10) comprises an elastic telescopic rod (9041) fixedly connected to the piston (902) and a positioning rod body (9042) fixedly connected to the elastic telescopic rod (9041); the positioning rod body (9042) is movably inserted into the positioning groove (11) and movably abuts against the sliding plate (8); a first inclined surface (9043) and a second inclined surface (9044) are respectively provided on both sides of the positioning rod body (9042); the cross-sectional length of the first inclined surface (9043) is greater than the cross-sectional length of the second inclined surface (9044).

Images