Preparation device of iron-carbon material for repairing petroleum-contaminated soil

Abstract

The utility model belongs to the technical field of preparation of environment-friendly catalytic materials, and particularly relates to a preparation device of an iron-carbon material for repairing petroleum-contaminated soil. The utility model discloses a preparation device of an iron-carbon material for repairing petroleum-contaminated soil. The preparation device comprises a stirring and dipping unit and an airflow heat treatment unit which are connected in sequence, wherein the stirring and dipping unit is provided with a feeding hole and a stirring device; the airflow heat treatment unit comprises a heat treater, an air inlet and an air outlet are formed in the heat treater, and a sedimentation device is arranged in the heat treater; the inlet end of the heat processor is connected to the discharging end of the stirring and dipping unit, and the outlet end of the heat processor is connected with a liquid discharging device. The device can be used for preparing the iron-carbon material for reinforcing the persulfate to repair the petroleum-polluted soil in batches.

Description

Technical Field

[0001] The utility model belongs to the technical field of environmental protection catalytic material preparation, and in particular relates to a preparation device of an iron-carbon material for repairing petroleum-contaminated soil. Background Art

[0002] Generally speaking, the hazards of petroleum-contaminated soil are mainly: 1) changing the soil structure and properties, resulting in reduced crop yields and vegetation destruction, and harmful substances will indirectly enter the human body, endangering life and health; 2) petroleum components and heavy metal ions in the contaminated soil will enter the water body and the atmosphere in the form of runoff, leakage and evaporation, thereby affecting drinking water safety and air quality.

[0003] At present, there are many introductions to the methods, materials and equipment for the treatment of petroleum-contaminated water bodies in the literature and practical applications, such as adsorption / regeneration, Fenton homogeneous / heterogeneous oxidation, filtration separation, microbial degradation, etc., but there are few reports on the treatment of petroleum-contaminated soil, which are only limited to mixed landfill, high-temperature treatment, plant / microorganism purification, etc., which have the disadvantages of long treatment time, great damage to soil properties, limited treatment volume and high cost. Therefore, it is urgent to develop efficient petroleum-contaminated soil treatment technology.

[0004] The persulfate advanced oxidation system can generate active free radicals (SO4 - ∙, HO∙, etc.), which have a good degradation effect on macromolecules / heavy organic hydrocarbons / toxic and harmful substances in petroleum hydrocarbons, thereby achieving pollutant reduction, low harm or harmlessness. Fe-containing substances with reducing effects are the key to promoting persulfate to produce active free radicals, and C that does not chemically react with Fe is a better matrix for dispersing, fixing and carrying Fe substances. Therefore, iron-carbon composite materials can better enhance the oxidation and degradation of petroleum organic pollutants by persulfate. If the C-based carrier has the characteristics of large specific surface area, porosity, surface affinity modification groups, etc., it will also have a better purification effect on heavy metal ions in petroleum-contaminated soil. At the same time, with the help of the existing ferromagnetism or load magnetization modification of iron-carbon materials, it can achieve its rapid and effective separation and recycling in complex application environments.

[0005] Based on the above understanding, the preparation of multifunctional iron-carbon composite materials is crucial, but there are few reports on the preparation of iron-carbon materials for oil-contaminated soil remediation. The common preparation methods of iron-carbon materials are high-temperature fusion and physical bonding, which have problems such as poor component uniformity, small active surface and low load strength. Therefore, there is an urgent need for a preparation device that can adapt to the requirements of oil-contaminated soil remediation and the characteristics of iron-carbon materials. Summary of the invention

[0006] The utility model aims to solve the above problems and proposes a preparation device for iron-carbon materials for repairing petroleum-contaminated soil. The device combines liquid-phase impregnation loading, step-by-step solid-liquid sedimentation separation and gas-phase drying / calcination / reduction to successively realize adsorption and uniform dispersion of Fe-containing substances on C-based carriers, effective separation of solid-phase iron-carbon impregnation loading and environmental liquid phase, and fixation / fusion / exposure of catalytically active substances, so as to batch prepare multifunctional iron-carbon composite materials for strengthening persulfate repair of petroleum-contaminated soil.

[0007] The technical solution of the utility model is:

[0008] A preparation device for iron-carbon material for repairing petroleum-contaminated soil comprises a stirring and impregnation unit and an airflow heat treatment unit connected in sequence; wherein the stirring and impregnation unit is provided with a feed port and a stirring device; the airflow heat treatment unit comprises a heat treatment device, the heat treatment device is provided with an air inlet and an exhaust port, and a sedimentation device is provided in the heat treatment device; the inlet end of the heat treatment device is connected to the unloading end of the stirring and impregnation unit, and the outlet end of the heat treatment device is connected to a drainage device.

[0009] Among them, the stirring and impregnation unit includes a cylindrical impregnation kettle, the top cover of which is an upper sealing flange; the feed port includes a solid phase feeding port and a liquid phase feeding port; the impregnation kettle is also provided with a stirring device; the liquid holding height in the impregnation kettle is 1 / 2-3 / 4 of the cylindrical height; a feed pipe is provided at the bottom end of the impregnation kettle, and the inner diameter of the feed pipe is 1 / 10-1 / 9 of the inner diameter of the impregnation kettle.

[0010] The heat treatment device comprises an inclined section body and a horizontal section body connected in sequence, the length of the horizontal section body is 1-1.2 times the inner diameter of the heat treatment device; a discharge pipe is connected to the end of the horizontal section body, the inner diameter of the discharge pipe is 1 / 10-1 / 5 of the inner diameter of the heat treatment device, and its length is 1-2 times the inner diameter of the heat treatment device; the inclined section body is 30°-45° with the horizontal plane; the inclined section body is provided with a stepped sedimentation separation inclined plate in the direction from the air inlet to the exhaust port, the number of the stepped sedimentation separation inclined plates is 10-15, and the width is 1 / 2 of the inner diameter of the heat treatment device or the same as the inner diameter of the heat treatment device; a horseshoe-shaped step is axially arranged on the upper edge of each layer of the sedimentation separation inclined plate, and the number of the horseshoe-shaped step is consistent with the number of the stepped sedimentation separation inclined plates; the slope of the horseshoe-shaped step is 20°-30° with the stepped sedimentation separation inclined plate, and the back is 45°-60° with the stepped sedimentation separation inclined plate; the feed pipe extends into the horseshoe-shaped step located in the first position.

[0011] Among them, the solid phase feeding port and the liquid phase feeding port are symmetrically arranged along the center of the upper sealing flange, and both penetrate the upper sealing flange and extend to the impregnation kettle; the solid phase feeding port / liquid phase feeding port includes a hollow inverted tetrahedron and a column connected in sequence from top to bottom; wherein, the side length of the lower mouth of the inverted tetrahedron is 2-3 times the diameter of the swirl injection port, and the side length of the upper mouth is 3 times the side length of the lower mouth; the height of the inverted tetrahedron is 3 / 10-2 / 5 of the diameter of the upper sealing flange.

[0012] Among them, the feed port also includes a swirl injection port, which is provided with 4 swirl injection ports and is evenly distributed on the same circumference; the swirl injection port is cylindrical, and a swirl channel is provided under each swirl injection port, and the swirl channel is 30°-45° with the upper sealing flange; the projection of the 4 swirl channels on the upper sealing flange is counterclockwise; and the straight line where the projection is located is perpendicular to the straight line from the swirl injection port to the center of the circle where the circumference is located; the cross-sectional diameter of the swirl injection port is 1 / 20 of the diameter of the upper sealing flange; the cylindrical height is 2 / 5-1 / 2 of the diameter of the upper sealing flange; the distance between the center of the swirl injection port and the center of the upper sealing flange is 2 / 5-3 / 5 of the radius of the upper sealing flange; the length of the swirl channel is 1-2 times the thickness of the upper sealing flange.

[0013] The stirring device comprises a motor located outside the impregnation kettle, a stirring rod penetrating the upper sealing flange and a stirring paddle located inside the impregnation kettle, which are connected in sequence; the length of the stirring rod extending to the impregnation kettle is 3 / 4-4 / 5 of the height of the impregnation kettle; the number of paddles of the stirring paddle is 2-4, and the length of the paddle is 1 / 4-3 / 10 of the inner diameter of the impregnation kettle.

[0014] Wherein, a shaped filtering filler layer is provided at the connection between the horizontal section body and the discharge pipe; the thickness of the shaped filtering filler layer is 1 / 10-1 / 5 of the inner diameter of the heat treatment unit.

[0015] The outer wall of the impregnation kettle is also wrapped with an impregnation kettle heating jacket, and the upper limit of the insulation of the impregnation kettle heating jacket is 90°C; the outer wall of the inclined section body is wrapped with a heat treatment device heating jacket, and the upper limit of the insulation of the heat treatment device heating jacket is 1000°C.

[0016] The end of the horizontal section body is sealed by a lower sealing flange, and the exhaust port penetrates the lower sealing flange and extends into the heat treatment unit.

[0017] Wherein, the feed pipe is provided with a feed ball valve, and the drain pipe is provided with a drain pipe ball valve.

[0018] The technical effects of the utility model are:

[0019] The utility model provides a preparation device for an iron-carbon material for repairing petroleum-contaminated soil, which solves the problems of poor uniformity of product components, small active surface and low loading strength existing in conventional iron-carbon material preparation devices. The utility model combines a liquid phase impregnation loading process, a solid-liquid two-phase separation process and a solid phase heat treatment process to achieve uniform dispersion, firm bonding and effective reduction of Fe-containing substances on a C-based carrier, thereby exposing catalytically active substances to the greatest extent, and can prepare iron-carbon materials in batches for strengthening persulfate repair of petroleum-contaminated soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The utility model is a schematic structural diagram of a device for preparing an iron-carbon material for repairing petroleum-contaminated soil.

[0021] Figure 2 It is a cross-sectional view of the solid-liquid feeding unit.

[0022] Figure 3 This is a schematic diagram of the structure of the stepped sedimentation separation inclined plate.

[0023] Figure numerals: 1, motor; 2, stirring rod; 3, swirl injection port; 3*, swirl channel; 4a, solid phase feeding port; 4b, liquid phase feeding port; 5, upper sealing flange; 6, stirring paddle; 7, impregnation kettle heating jacket; 8, impregnation kettle; 9, discharge ball valve; 10, discharge pipe; 11, air inlet; 12, heat treatment device; 13, stepped sedimentation separation inclined plate; 13*, horseshoe-shaped step; 14, heat treatment device heating jacket; 15, shaped filter packing layer; 16, drain pipe ball valve; 17, drain pipe; 18, lower sealing flange; 19, exhaust port. DETAILED DESCRIPTION

[0024] Example 1

[0025] A preparation device for iron-carbon material for repairing petroleum-contaminated soil, comprising a stirring and impregnation unit and an airflow heat treatment unit connected in sequence; wherein the stirring and impregnation unit is provided with a feed port and a stirring device; the airflow heat treatment unit comprises a heat treatment unit 12, the heat treatment unit 12 is provided with an air inlet 11 and an exhaust port 19, and a sedimentation device is provided in the heat treatment unit 12; the inlet end of the heat treatment unit 12 is connected to the discharge end of the stirring and impregnation unit, and the outlet end of the heat treatment unit 12 is connected to a liquid discharge device.

[0026] The specific implementation process of this embodiment is as follows:

[0027] (1) adding a liquid phase (impregnation liquid or pure water) and a solid phase (C-based carrier particles, or sequentially adding a soluble Fe-containing salt, a modifier, and C-based carrier particles) through a feed port, and the liquid phase and the solid phase are mixed in a stirring and impregnation unit to form a mixed liquid for impregnation;

[0028] (2) After the impregnation is completed, the mixed liquid flows from the stirring and impregnation unit to the thermal treatment device 12;

[0029] (3) The mixed liquid is separated into solid and gas in the heat treatment unit 12.

[0030] Example 2

[0031] On the basis of Example 1, it also includes: the stirring and impregnation unit includes a cylindrical impregnation kettle 8, the top cover of the impregnation kettle 8 is an upper sealing flange 5; the feed port includes a solid phase feeding port 4a and a liquid phase feeding port 4b; the impregnation kettle 8 is also provided with a stirring device; the liquid holding height in the impregnation kettle 8 is 1 / 2-3 / 4 of the cylindrical height; the bottom end of the impregnation kettle 8 is provided with a discharge pipe 10, and the inner diameter of the discharge pipe 10 is 1 / 10-1 / 9 of the inner diameter of the impregnation kettle 8.

[0032] Example 3

[0033] On the basis of Example 2, it also includes: the heat treatment device 12 includes an inclined section body and a horizontal section body connected in sequence, the length of the horizontal section body is 1-1.2 times the inner diameter of the heat treatment device 12; the end of the horizontal section body is connected to a discharge pipe, the inner diameter of the discharge pipe 17 is 1 / 10-1 / 5 of the inner diameter of the heat treatment device 12, and its length is 1-2 times the inner diameter of the heat treatment device 12; the inclined section body is 30°-45° with the horizontal plane; the inclined section body is provided with a stepped sedimentation separation inclined plate along the direction from the air inlet 11 to the exhaust port 19 Plate 13, the number of step sedimentation separation inclined plates 13 is 10-15, and the width is 1 / 2 of the inner diameter of the heat treatment device 12 or is consistent with the inner diameter of the heat treatment device 12; a horseshoe-shaped step 13* is axially arranged on the upper edge of each layer of sedimentation separation inclined plate, and the number of the horseshoe-shaped step 13* is consistent with the number of the step sedimentation separation inclined plates 13; the slope of the horseshoe-shaped step 13* is 20°-30° with the step sedimentation separation inclined plate 13, and the back is 45°-60° with the step sedimentation separation inclined plate 13; the feed pipe 10 extends into the horseshoe-shaped step 13* located in the first position.

[0034] Example 4

[0035] On the basis of Example 3, it also includes: the solid phase feeding port 4a and the liquid phase feeding port 4b are symmetrically arranged along the center of the upper sealing flange 5, both penetrate the upper sealing flange 5 and extend to the impregnation kettle 8; the solid phase feeding port 4a / liquid phase feeding port 4b includes a hollow inverted tetrahedron and a column connected in sequence from top to bottom; wherein, the side length of the lower opening of the inverted tetrahedron is 2-3 times the diameter of the swirl injection port 3, and the side length of the upper opening is 3 times the side length of the lower opening; the height of the inverted tetrahedron is 3 / 10-2 / 5 of the diameter of the upper sealing flange 5.

[0036] Example 5

[0037] On the basis of Example 4, it also includes: the feed port also includes a swirl injection port 3, and the swirl injection port 3 is provided with 4 and is evenly distributed on the same circumference; the swirl injection port 3 is cylindrical, and each swirl injection port 3 is provided with a swirl channel 3*, and the swirl channel 3* is 30°-45° with the upper sealing flange 5; the projections of the four swirl channels 3* on the upper sealing flange 5 are counterclockwise; and the straight line where the projection is located is perpendicular to the straight line from the swirl injection port 3 to the center of the circle where the circumference is located; the cross-sectional diameter of the swirl injection port 3 is 1 / 20 of the diameter of the upper sealing flange 5; the cylindrical height is 2 / 5-1 / 2 of the diameter of the upper sealing flange 5; the distance between the center of the swirl injection port 3 and the center of the upper sealing flange 5 is 2 / 5-3 / 5 of the radius of the upper sealing flange 5; the length of the swirl channel 3* is 1-2 times the thickness of the upper sealing flange 5.

[0038] Example 6

[0039] On the basis of Example 5, it also includes: the stirring device includes a motor 1 located outside the impregnation kettle 8, a stirring rod 2 penetrating the upper sealing flange 5 and a stirring paddle 6 located in the impregnation kettle 8, which are connected in sequence; the length of the stirring rod 2 extending to the impregnation kettle 8 is 3 / 4-4 / 5 of the height of the impregnation kettle 8; the number of paddles of the stirring paddle 6 is 2-4, and the length of the paddle is 1 / 4-3 / 10 of the inner diameter of the impregnation kettle 8.

[0040] Example 7

[0041] On the basis of Example 6, it also includes: a shaped filtering filler layer 15 is provided at the connection between the horizontal section body and the discharge pipe; the thickness of the shaped filtering filler layer 15 is 1 / 10-1 / 5 of the inner diameter of the heat treatment device 12.

[0042] Example 8

[0043] On the basis of Example 7, it also includes: the outer wall of the impregnation kettle 8 is also wrapped with an impregnation kettle heating jacket 7, and the upper insulation limit of the impregnation kettle heating jacket 7 is 90°C; the outer wall of the inclined section body is wrapped with a heat treatment device heating jacket 14, and the upper insulation limit of the heat treatment device heating jacket 14 is 1000°C; the end of the horizontal section body is sealed by a lower sealing flange 18, and the exhaust port 19 penetrates the lower sealing flange 18 and extends into the heat treatment; the discharge pipe 10 is provided with a discharge ball valve 9, and the drain pipe 17 is provided with a drain pipe ball valve 16.

[0044] The specific implementation process of this embodiment is:

[0045] Add the prepared impregnation liquid or pure water through the liquid phase feeding port 4b until the liquid holding height in the impregnation kettle 8 is 1 / 2-3 / 4 of the cylindrical height; start the motor 1, gradually increase the stirring speed to 200-400 rpm, and at the same time, energize the impregnation kettle heating jacket 7 to keep the liquid phase warm to 30-80°C. Add C-based carrier particles through the solid phase feeding port 4a, or add soluble Fe-containing salt, modifier and C-based carrier particles in sequence, and control the mixed impregnation time to 12-24 hours.

[0046] After the impregnation is completed, the stirring speed is reduced to 100-200 rpm, and the discharge pipe ball valve 16 and the discharge ball valve 9 are opened in sequence, and the impregnation kettle heating jacket 7 is closed, so that the mixed liquid is discharged from the impregnation kettle 8 and flows to the discharge pipe 17 along the stepped sedimentation separation inclined plate 13.

[0047] After the mixed liquid is spread, the flow rate decreases and the solid phase sinks due to gravity, and the C-based particles loaded with Fe-containing substances are gradually deposited on the slope and back of the multi-stage horseshoe-shaped terrace 13*. A small amount of particles that cannot be deposited are intercepted by the shaped filtering filler layer 15 at the tail end and flow out from the drainage pipe 17.

[0048] When the height of the mixed liquid in the impregnation kettle 8 drops to the stirring paddle 6, the impregnation liquid or pure water is introduced from the cyclone injection port 3, and the pure water is used to wash the inner wall of the impregnation kettle 8 and increase the liquid phase disturbance by using the booster and cyclone channel 3*. Since the injection amount is less than the discharge amount of the impregnation kettle 8, all the materials in the impregnation kettle 8 are finally transferred to the heat treatment device 12. When the flow rate of the drain pipe 17 is significantly reduced, the motor 1 and the cyclone injection are stopped. When the drain pipe 17 no longer flows out liquid, the discharge ball valve 9 of the impregnation kettle 8 and the discharge pipe ball valve 16 are closed in turn.

[0049] A certain flow of N2 or air is introduced from the air inlet 11 of the heat processor 12, and the heat processor heating jacket 14 is powered on to keep the heat processor 12 warm to 105-120°C. The air flow carrying water vapor and volatile desorbed products flows out from the exhaust port 19 of the heat processor 12, and the drying time is controlled at 2-4 hours.

[0050] After drying, an inert gas such as N2 is introduced from the air inlet 11 of the heat treatment device 12, and the heat treatment device 12 is heated to 400-600°C. The air flow carrying the thermally decomposed light substances flows out from the exhaust port 19 of the heat treatment device 12, and at the same time, the Fe-containing substances are evenly distributed and fused on the C-based particles. The roasting time is controlled at 2-4 hours.

[0051] After calcination, a reducing gas such as H2 is introduced from the air inlet 11 of the heat treatment device 12, and the heat treatment device 12 is heated to 600-900°C. The gas flow carrying H-containing substances flows out from the exhaust port 19 of the heat treatment device 12, and at the same time, active zero-valent iron Fe substances are exposed on the inner and outer surfaces of the C-based carrier, and the reduction time is controlled at 2-4 h.

[0052] After the reduction is completed, an inert gas such as N2 is introduced from the air inlet 11 of the heat treatment device 12, and the heat treatment device heating jacket 14 is closed, and the heat treatment device 12 is gradually cooled. When the temperature drops to room temperature, the lower sealing flange 18 of the heat treatment device 12 is opened, the stepped sedimentation separation inclined plate 13 is taken out, and the prepared iron-carbon material is collected.

Claims

1. A preparation device for iron-carbon materials for repairing petroleum-contaminated soil, comprising a stirring and impregnation unit and an airflow heat treatment unit connected in sequence; characterized in that: in, The stirring and impregnation unit is provided with a feed port and a stirring device; the airflow heat treatment unit comprises a heat treatment unit (12), the heat treatment unit (12) is provided with an air inlet (11) and an air outlet (19), and a sedimentation device is provided inside the heat treatment unit (12); the inlet end of the heat treatment unit (12) is connected to the unloading end of the stirring and impregnation unit, and the outlet end of the heat treatment unit (12) is connected to a liquid discharge device.

2. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 1, characterized in that: The stirring and impregnation unit comprises a cylindrical impregnation kettle (8), the top cover of the impregnation kettle (8) is an upper sealing flange (5); the feed port comprises a solid phase feed port (4a) and a liquid phase feed port (4b); the impregnation kettle (8) is also provided with a stirring device; the liquid holding height in the impregnation kettle (8) is 1 / 2-3 / 4 of the cylindrical height; and the bottom end of the impregnation kettle (8) is provided with a discharge pipe (10).

3. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 2, characterized in that: The heat treatment device (12) comprises an inclined section body and a horizontal section body connected in sequence, the end of the horizontal section body is connected to a discharge pipe; the inclined section body is at an angle of 30°-45° to the horizontal plane; a stepped sedimentation separation inclined plate (13) is provided inside the inclined section body along the direction from the air inlet (11) to the exhaust port (19), and a horseshoe-shaped step (13*) is axially arranged on the upper edge of each layer of the sedimentation separation inclined plate, the slope of the horseshoe-shaped step (13*) is at an angle of 20°-30° to the stepped sedimentation separation inclined plate (13), and the back side is at an angle of 45°-60° to the stepped sedimentation separation inclined plate (13); the discharge pipe (10) extends into the horseshoe-shaped step (13*) located at the first position.

4. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 3, characterized in that: The solid-phase feeding port (4a) and the liquid-phase feeding port (4b) are symmetrically arranged along the center of the upper sealing flange (5), and both penetrate the upper sealing flange (5) and extend to the impregnation kettle (8); the solid-phase feeding port (4a) / liquid-phase feeding port (4b) comprises, from top to bottom, a hollow inverted quadrangular pyramid and a column connected in sequence.

5. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 4, characterized in that: The feed port also includes a swirl injection port (3), which is provided with four swirl injection ports (3) and is evenly distributed on the same circumference; the swirl injection port (3) is cylindrical, and each swirl injection port (3) is provided with a swirl channel (3*), and the swirl channel (3*) is at an angle of 30°-45° with the upper sealing flange (5); the projections of the four swirl channels (3*) on the upper sealing flange (5) are oriented counterclockwise; and the straight line on which the projections are located is perpendicular to the straight line from the swirl injection port (3) to the center of the circumference.

6. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 5, characterized in that: The stirring device comprises a motor (1) located outside the impregnation kettle (8), a stirring rod (2) penetrating the upper sealing flange (5), and a stirring paddle (6) located inside the impregnation kettle (8), which are connected in sequence.

7. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 6, characterized in that: A shaped filtering filler layer (15) is provided at the connection between the horizontal section body and the discharge pipe.

8. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 7, characterized in that: The outer side wall of the impregnation kettle (8) is also wrapped with an impregnation kettle heating jacket (7), and the outer side wall of the inclined section body is wrapped with a heat treatment device heating jacket (14).

9. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 8, characterized in that: The end of the horizontal section body is sealed by a lower sealing flange (18), and the exhaust port (19) penetrates the lower sealing flange (18) and extends into the heat treatment unit.

10. The device for preparing the iron-carbon material for repairing petroleum-contaminated soil according to claim 9, characterized in that: The feed pipe (10) is provided with a feed ball valve (9), and the liquid discharge pipe (17) is provided with a liquid discharge pipe ball valve (16).

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