A continuous reaction device for mineralizing and sequestering CO2 gas in a coal-based solid waste slurry

Abstract

The present invention discloses a continuous reaction device for mineralizing and sequestering CO₂ gas with coal-based solid waste slurry, which comprises a shell. Inside the shell, there are a turbine stirring section, a fluidized mixing section, and a spiral reaction section from top to bottom in sequence. A baffle plate is arranged below the slurry inlet, and several pairs of turbine stirrers arranged horizontally are successively arranged below the baffle plate from top to bottom. An outer gas pipe and a gas inlet are arranged outside the fluidized mixing section. An inner gas pipe, a first hollow semi-circular corrugated plate, and a second hollow semi-circular corrugated plate are arranged inside the fluidized mixing section. The gas inlet is communicated with the outer gas pipe, the inner gas pipe is communicated with the bottom of the outer gas pipe, the outer gas pipe is communicated with the second hollow semi-circular corrugated plate, and the inner gas pipe is communicated with the first hollow semi-circular corrugated plate. In the present invention, the slurry flows through the first hollow semi-circular corrugated plate and the second hollow semi-circular corrugated plate which are longitudinally staggered. The slurry is continuously divided and converged by the corrugated plates, and while changing the flow direction, it is successively deflected downward, accelerating the mixing and reaction of the gas and the slurry.

Description

Technical Field

[0001] The present invention relates to the technical field of mineralization and sequestration of coal-based solid waste slurries, and particularly to a continuous reaction device for mineralization and sequestration of CO2 gas in coal-based solid waste slurries. Background Art

[0002] Global warming caused by the greenhouse effect has affected the survival and development of mankind, and CO2 emission reduction is urgent. Carbon dioxide capture, utilization, and storage (CCUS) technology is a necessary means to achieve a large-scale reduction of CO2 emissions at the present stage. CCUS technology mainly includes CO2 capture, CO2 transportation, CO2 storage, and utilization. Among them, CO2 storage is mainly to achieve the permanent isolation of CO2 from the atmosphere. Coal-based solid waste slurries such as fly ash and coal gangue are often used as plugging materials in coal mines. The calcium and magnesium ions contained therein can be used as ideal raw materials for sequestering carbon dioxide, and the strength of the slurry can be enhanced to a certain extent after mineralization and sequestration of CO2. Therefore, sequestering CO2 in the plugging slurry and injecting it into the coal pillars or roadway fissures in the coal mine will become a new green and environmental protection direction for sequestering and utilizing CO2.

[0003] Since gas in coal mines is flammable and explosive when encountering electric sparks, and the cost of general explosion-proof devices is high and it is difficult to maintain. A static reactor is a tubular mixing device that can achieve continuous mixing or reaction of two or more fluids. The static reactor has no moving components, but uses the movement of the fluid itself to achieve fluid mixing under the action of mixing elements. Therefore, there is no electric spark, and it is very safe and reliable to apply it to coal mines. At present, most of the mineralization and sequestration devices use reaction kettle devices with motor mechanical stirring, and do not consider explosion-proof performance. There is no special static mixing device for solid waste slurries and gases at the coal mine site. Therefore, there is a broad application prospect for mixing and sequestering CO2 with slurries using a static reactor.

[0004] Patents CN201848207U and CN205328631U respectively use stainless steel corrugated packing and Pall ring packing to achieve full mixing and reaction of gas-liquid, but they both have the disadvantages of single mixing method and insufficient reaction. Especially when applied to the reaction of gas and slurry, the solid-phase particles in the slurry are likely to remain on the packing, and the quality of the slurry and the mixing effect are greatly reduced; secondly, the contact method between the gas-phase raw material and other raw materials in the reaction is single, and it is only introduced through the inlet pipeline, with a small contact area, and the bubbles may be difficult to penetrate deep inside. Summary of the Invention

[0005] Aiming at the problems existing in the above-mentioned prior art, the present invention provides a continuous reaction device for mineralization and sequestration of CO2 gas in coal-based solid waste slurries, which is energy-saving, environmentally friendly, highly safe, the gas penetrates deep into the slurry, the reaction is sufficient, there is no hanging material and no blockage of air holes.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0007] A continuous reaction device for mineralizing and sealing CO2 gas using coal-based solid waste slurry, comprising a shell, wherein the interior of the shell is provided with a turbine stirring section, a fluidized mixing section, and a spiral reaction section from top to bottom;

[0008] The upper end of the turbine stirring section is provided with a slurry inlet, and the right end of the spiral reaction section is provided with a discharge port.

[0009] A baffle is provided at the lower end of the slurry inlet, and a plurality of turbine agitators arranged in pairs in the horizontal direction are provided at the lower end of the baffle from top to bottom;

[0010] The outside of the fluidized mixing section is equipped with an external gas pipe and a gas inlet.

[0011] The fluidized mixing section is provided with an inner air pipe, a plurality of first hollow semicircular corrugated plates, and a plurality of second hollow semicircular corrugated plates. The gas inlet is connected to the outer air pipe, the inner air pipe is connected to the bottom of the outer air pipe, the outer air pipe is connected to the second hollow semicircular corrugated plates; the inner air pipe is connected to the first hollow semicircular corrugated plates;

[0012] The spiral reaction section is provided with a spiral stirrer. The spiral stirrer comprises a stirring shaft driven by an air motor, and spiral blades are uniformly welded on the stirring shaft.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] 1. The present invention is energy-saving, environmentally friendly, green and efficient, does not generate static sparks, and is suitable for underground coal mine operations. The structure is L-shaped and adopts segmented mixing and stirring to fully mix and react CO2 with the slurry. The upper slurry inlet can be directly connected to the slurry inlet pipeline flange, and the gas enters the internal and external air pipes through the side air inlet, and then is dispersed into each hollow semicircular corrugated plate, enters through the dense micropores at the bottom of the corrugated plate and is dispersed inside the reaction chamber. The lower end discharge port can directly discharge the material or be connected to the slurry pipeline to transport the reaction slurry, forming a continuous mixing inlet and outlet system.

[0015] 2. After the slurry enters from the upper slurry inlet of the present invention, it first enters the turbine stirring section. The slurry is converged by the baffle plate and impacts one side of the blades of the turbine stirrer, driving the straight blades to rotate. At the same time, the gas introduced from the lower corrugated plate floats up and mixes with the slurry. While the gas and the slurry are cut by the straight blades, the slurry will drive the straight blades to rotate and stir, converting the kinetic energy of the flowing slurry and the gravitational potential energy of the slurry into the mechanical energy of the rotation of the turbine stirrer, so that the gas and the slurry are fully mixed and stirred. The slurry continuously impacts the straight blades and is driven to rotate by the blades. When the fluid with inertia encounters an obstacle or a bend during the flow process, the flow velocity changes, thereby driving the surrounding fluid to form a vortex. Since the adjacent two turbines are symmetrically arranged and the arrangement directions of the straight blades are opposite, flow fields with opposite rotation directions are formed, intensifying the extrusion and collision of the gas and the slurry.

[0016] 3. After the gas-slurry of the present invention falls from the turbine stirring section to the fluidized mixing section, the kinetic energy of the slurry is greatly consumed and it falls onto the hollow semi-circular corrugated plate. The slurry is distributed in a fluidized manner. While the slurry flows downward along the hollow semi-circular corrugated plate, it also flows along the gap between the two semi-circular cross-section protrusions. At the same time, the gas also flows out from the air holes at the lower part of the corrugated plate, greatly increasing the contact area and contact time between the gas and the slurry.

[0017] 4. In the present invention, the slurry flows through the first hollow semi-circular corrugated plate and the second hollow semi-circular corrugated plate which are longitudinally staggered. The slurry is continuously split and converged by the corrugated plates, changing the flow direction and folding downward in turn. While the slurry is flowing, it is squeezed and cut by the gas ejected from the air holes on the lower surface of the corrugated plate, thereby forming continuous extrusion and collision between the slurry and the slurry, and between the slurry and the gas, promoting the dissolution of the gas in the slurry and accelerating the mixing and reaction of the gas and the slurry.

[0018] 5. In the present invention, the gas penetrates deep into the slurry, continuously interlaces and mixes and reacts with the slurry. And considering the adhesiveness of the slurry, the surface of the corrugated plate is smooth and inclined downward, so that the solid-phase particles in the slurry and the slurry will not be retained on the surface of the corrugated plate. The micro air holes are evenly arranged on the lower surface of the corrugated plate, and high-pressure gas is ejected from the air holes, and the solid-phase particles will not enter the interior of the hollow corrugated plate through the air holes.

[0019] 6. In the spiral reaction section of the present invention, the stirring shaft is driven to rotate by a pneumatic motor, thereby driving the spiral blades connected to the shaft to rotate, which is energy-saving and environmentally friendly and does not generate electric sparks. To make up for the insufficient reaction of the gas-slurry in the fluidized mixing section, where only a large amount of gas-containing slurry is produced, a spiral reaction section is provided. It increases the chaotic movement of the materials, enables the raw materials to react more fully, and at the same time the spiral blades can fully stir and fold the mixed materials with each other and spiral forward and convey them to the discharge port. And when facing materials with slow reaction, all the inlet and outlet ports can be closed, so that the materials are stirred in the spiral reaction section until they are fully reacted and then the materials are output. Description of the Drawings

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 Structural schematic diagram of the present invention;

[0022] Figure 2 Structural schematic diagram of a hollow semi-cylindrical corrugated plate;

[0023] Figure 3 Structural schematic diagram of the bottom of the hollow semi-cylindrical corrugated plate;

[0024] Figure 4 Structural schematic diagram of a turbine agitator.

[0025] In the figure: 1, slurry inlet; 2, housing; 3, baffle plate; 4, turbine agitator; 4-1, solid shaft; 4-2, rolling bearing; 4-3, straight plate blade; 5, first hollow semi-cylindrical corrugated plate; 6, second hollow semi-cylindrical corrugated plate; 7, air inlet; 8, outer air pipe; 8-1, first outer air pipe; 8-2, second outer air pipe; 8-3, branch pipe; 9, inner air pipe; 10, pneumatic motor; 11, stirring shaft; 12, spiral blade; 13, front end bearing; 14, rear end bearing; 15, support arm; 16, discharge port; 17, semi-circular cross-section protrusion; 18, micropores; 20: turbine stirring section; 21, fluidized mixing section; 22, spiral reaction section. Specific embodiments

[0026] The following further describes the specific embodiments of the present invention in conjunction with the drawings.

[0027] As Figures 1-4 shown, a continuous reaction device for mineralizing and sequestering CO2 gas in a coal-based solid waste slurry includes a housing 2. Inside the housing 2, there are a turbine stirring section 20, a fluidized mixing section 21, and a spiral reaction section 22 from top to bottom in sequence. At the upper end of the turbine stirring section 20, there is a slurry inlet 1. At the right end of the spiral reaction section 22, there is a discharge port 16. At the lower end of the slurry inlet 1, there is a baffle plate 3. Below the baffle plate 3, there are a number of turbine agitators 4 arranged in pairs in the horizontal direction from top to bottom in sequence. The turbine stirring section 20 also includes a solid shaft 4-1 and a rolling bearing 4-2. The solid shaft 4-1 is vertically fixed on the housing 2. The turbine agitator 4 is connected to the solid shaft 4-1 through the rolling bearing 4-2. A number of straight plate blades 4-3 are evenly distributed on the turbine agitator 4. The determination methods for the diameter d of the straight plate blade 4-3 and the rotation speed N of the turbine agitator 4 are as follows:

[0028] According to the rotational fluid flow rate threshold Q discharged by the straight plate blades d* and the total circulation flow rate threshold Q c* , such that the following equation holds:

[0029] Qd = Nqd·Nd 3 ≥Q d*

[0030] Qc = Nqc·Nd 3 ≥Q c*

[0031] Wherein, Qd is the rotational fluid flow rate discharged by the straight plate blades, Q1 is the fluid flow rate of the circulating flow driven by the discharged rotational fluid, Qc = Qd + Q1, Nqd is the straight plate blade discharge flow coefficient, and Nqc is the total circulation flow coefficient.

[0032] An outer air pipe 8 and a gas inlet 7 are provided outside the fluidized mixing section 21. An inner air pipe 9, a plurality of first hollow semi-circular corrugated plates 5, and a plurality of second hollow semi-circular corrugated plates 6 are provided inside the fluidized mixing section 21. The gas inlet 7 is communicated with the outer air pipe 8, the inner air pipe 9 is communicated with the bottom of the outer air pipe 8, and the outer air pipe 8 is communicated with the second hollow semi-circular corrugated plate 6; the inner air pipe 9 is communicated with the first hollow semi-circular corrugated plate 5; the outer air pipe 8 includes a first outer air pipe 8-1 and a second outer air pipe 8-2 symmetrically arranged about the inner air pipe 9 on the left and right. The inner air pipe 9, the first outer air pipe 8-1, and the second outer air pipe 8-2 are all vertically arranged and communicated at the bottom. The gas inlet 7 is communicated with the first outer air pipe 8-1. A plurality of branch pipes 8-3 are evenly distributed in the vertical direction of the outer air pipe 8. The branch pipes 8-3 penetrate through the housing 2 and are communicated with the second hollow semi-circular corrugated plate 6; a plurality of first hollow semi-circular corrugated plates 5 are evenly distributed in the vertical direction of the inner air pipe 9. The first hollow semi-circular corrugated plates 5 are symmetrically arranged about the inner air pipe 9 on the left and right, and the first hollow semi-circular corrugated plates 5 and the second hollow semi-circular corrugated plates 6 are longitudinally staggered. The first hollow semi-circular corrugated plates 5 and the second hollow semi-circular corrugated plates 6 are arranged obliquely downward at an angle of 60°-80° with the vertical direction. The lower surfaces of the first hollow semi-circular corrugated plates 5 and the second hollow semi-circular corrugated plates 6 are provided with micro air holes 18, and the upper surfaces are provided with semi-circular cross-section protrusions 17.

[0033] The spiral reaction section 22 is provided with a spiral agitator. The spiral agitator includes a stirring shaft 11 driven by a pneumatic motor 10. Spiral blades 12 are uniformly welded on the stirring shaft 11. The front end of the stirring shaft 11 is connected to the front bearing 13, and the rear end is connected to the rear bearing 14. The front bearing 13 is fixed on the housing 2, and the rear bearing 14 is connected to the housing 2 through a support arm 15. The lift angle calculation formula of the spiral blade 12 is:

[0034]

[0035] Where: λ m represents the lift angle of the spiral blade;

[0036] s 导程 represents the distance between the spiral blades 12;

[0037] d 螺径 represents the size of the diameter of the spiral blades of the spiral agitator;

[0038] Substitute the lead s of the agitator 导程 = 35 cm, d 螺径 = 76 cm into the above formula, and the spiral angle λ of the agitator blades can be obtained m = 8.4°.

[0039] The spiral equation of the spiral blade 12 is:

[0040] x = a·cosθ

[0041] x = a·sinθ

[0042] z = ±b·θ = ±h·θ / (2π) = ±a·θcotβ

[0043] In the formula, x, y, and z are the coordinate values of the spiral in the three coordinate axis directions, θ = ωt, ω is the angular velocity, h is called the pitch, a and b are the trajectory parameters of the spiral, β is called the spiral angle, the positive sign is taken for the right-handed spiral, and the negative sign is taken for the left-handed spiral in the formula.

[0044] The operating power P of the stirring shaft 11 is calculated as follows:

[0045]

[0046] Among them: P represents the operating power of the agitator, unit: kw;

[0047] T represents the rotational torque of the stirring shaft, unit: Nm;

[0048] G represents the self-weight of the medium, unit: N;

[0049] D represents the mean diameter of the spiral agitator, unit: m;

[0050] [[ID=5D]]N 轴 represents the rotational speed of the agitator, unit: r / min;

[0051] η represents the transmission efficiency of the agitator;

[0052] λ m represents the spiral angle of the spiral blade, unit: degree;

[0053] ρ represents the friction angle between the medium sphere and the spiral blade, ρ = arctanu;

[0054] μ represents the friction coefficient between the medium and the blade.

[0055] The above are some preferred embodiments of the present invention. It should be noted that in the technical field, without departing from the actual principle and method of the present invention, appropriate modifications or adjustments can be made, and these modifications and adjustments should also be regarded as within the protection scope of the present invention.

Claims

1. A continuous reaction device for mineralizing and sequestering CO2 gas in a coal-based solid waste slurry, comprising a housing (2), characterized in that, Inside the housing (2), from top to bottom, there are a turbine stirring section (20), a fluidized mixing section (21), and a spiral reaction section (22) in sequence. At the upper end of the turbine stirring section (20), there is a slurry inlet (1), and at the right end of the spiral reaction section (22), there is a discharge port (16). At the lower end of the slurry inlet (1), there is a baffle plate (3), and below the baffle plate (3), there are several pairs of horizontally arranged turbine stirrers (4) from top to bottom in sequence. Outside the fluidized mixing section (21), there is an outer air pipe (8) and a gas inlet (7). Inside the fluidized mixing section (21), there is an inner air pipe (9), several first hollow semi-circular corrugated plates (5), and several second hollow semi-circular corrugated plates (6). The gas inlet (7) is connected to the outer air pipe (8), the inner air pipe (9) is connected to the bottom of the outer air pipe (8), and the outer air pipe (8) is connected to the second hollow semi-circular corrugated plate (6); the inner air pipe (9) is connected to the first hollow semi-circular corrugated plate (5). The spiral reaction section (22) is provided with a spiral stirrer, and the spiral stirrer includes a stirring shaft (11) driven by a pneumatic motor (10), and spiral blades (12) are uniformly welded on the stirring shaft (11).

2. The continuous reaction device for mineralizing and sealing CO2 gas with coal-based solid waste slurry according to claim 1, wherein The outer air pipe (8) includes a first outer air pipe (8-1) and a second outer air pipe (8-2) symmetrically arranged about the inner air pipe (9). The inner air pipe (9), the first outer air pipe (8-1), and the second outer air pipe (8-2) are all vertically arranged and connected at the bottom. The gas inlet (7) is connected to the first outer air pipe (8-1). The outer air pipe (8) is evenly provided with several branch pipes (8-3) in the vertical direction. The branch pipes (8-3) penetrate through the housing (2) and are connected to the second hollow semi-circular corrugated plate (6); the inner air pipe (9) is evenly provided with several first hollow semi-circular corrugated plates (5) in the vertical direction. The first hollow semi-circular corrugated plates (5) are symmetrically arranged about the inner air pipe (9), and the first hollow semi-circular corrugated plates (5) and the second hollow semi-circular corrugated plates (6) are longitudinally staggered. The first hollow semi-circular corrugated plates (5) and the second hollow semi-circular corrugated plates (6) are arranged obliquely downward at an angle of 60°-80° with the vertical direction. The lower surfaces of the first hollow semi-circular corrugated plates (5) and the second hollow semi-circular corrugated plates (6) are provided with micro-holes (18), and the upper surfaces are provided with semi-circular cross-section protrusions (17).

3. The continuous reaction device for mineralizing and sequestering CO2 gas in coal-based solid waste slurry according to claim 1, wherein The turbine stirring section (20) further includes a solid shaft (4-1) and a rolling bearing (4-2). The solid shaft (4-1) is vertically fixed on the housing (2), and the turbine stirrer (4) is connected to the solid shaft (4-1) through the rolling bearing (4-2). The turbine stirrer (4) is evenly provided with several straight plate blades (4-3), and the straight plate blades (4-3) of the paired turbine stirrers (4) are arranged in opposite directions.

4. The continuous reaction device for mineralizing and storing CO2 gas in coal-based solid waste slurry according to claim 1, characterized in that, The front end of the stirring shaft (11) is connected to the front end bearing (13), and the rear end is connected to the rear end bearing (14). The front end bearing (13) is fixed on the housing (2), and the rear end bearing (14) is connected to the housing (2) through a support arm (15).

5. The continuous reaction device for mineralizing and sequestering CO2 gas in coal-based solid waste slurry according to claim 3, characterized in that, The method for determining the diameter d of the straight plate blade (4-3) and the rotation speed N of the turbine stirrer (4) is as follows: According to the rotational fluid flow rate threshold Q discharged by the straight plate blade d* and the total circulation flow rate threshold Q c* , the following equation holds: Among them, Qc = Qd + Q1, where Qd is the flow rate of the rotating fluid discharged by the straight blade, Q1 is the flow rate of the fluid driven by the discharged rotating fluid to form a circulation, Qc is the sum of the flow rate of the rotating fluid discharged by the straight blade and the flow rate of the fluid driven by the discharged rotating fluid to form a circulation, Nqd is the discharge flow coefficient of the straight blade, and Nqc is the total circulation flow coefficient.

6. The continuous reaction device for mineralizing and storing CO2 gas in a coal-based solid waste slurry according to claim 1, wherein, The formula for calculating the lift angle of the helical blade (12) is: Where: λ m represents the helix blade lift angle; s 导程 represents the distance between the helical blades (12); d 螺径 represents the size of the diameter of the spiral blade of the spiral agitator.

7. The continuous reaction device for mineralization and sequestration of CO2 gas in coal-based solid waste slurry according to claim 1, characterized in that, The spiral equation of the helical blade (12) is: x = a × cosθ y = a × sinθ z = ±b × θ = ±h × θ / (2π) = ±a × θcotβ In the formula, x, y, and z are the coordinate values of the spiral in the three coordinate axis directions, θ = ωt, ω is the angular velocity, h is called the pitch, a and b are the trajectory parameters of the spiral, β is called the helix angle, the positive sign is taken for the right-handed helix, and the negative sign is taken for the left-handed helix.

8. The continuous reaction device for mineralizing and sequestering CO2 gas in coal-based solid waste slurry according to claim 1, wherein, The operating power P of the stirring shaft (11) is calculated as follows: Among them: P represents the operating power of the stirrer, unit: kw; T represents the torque of the stirring shaft rotation, unit: Nm; G represents the self-weight of the medium, unit: N; D represents the median diameter of the helical stirrer, unit: m; N 轴 represents the rotational speed of the agitator, unit: r / min; η represents the transmission efficiency of the stirrer; λ m represents the helix blade lift angle, unit: degree; ρ represents the friction angle between the medium and the helical blade, ρ = arctanμ; μ represents the friction coefficient between the medium and the blade.

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