CN105169818A - Double-vane air-swirl parallel-combination demister and application thereof - Google Patents

Abstract

The present invention relates to a double-vane air-swirl parallel-combination demister. The demister comprises one or more than two air-swirl demisting units and plugging plates, wherein a central axis of the air-swirl demisting unit is arranged in a vertical direction; and the air-swirl demisting unit comprises an outer barrel, a guide plate, an inner barrel, an outer guide vane, an inner guide vane, a sealing plate, a tapered section, an expanding section and a water drainage section. According to the demister disclosed by the invention, a working flow rate is increase and an ultimate grain size is reduced, so that the ultimate grain size of liquid drops captured by the demister is smaller than 15 microns, and therefore, effect of reducing the concentration of mist drops at an outlet of the demister is achieved, water loss is avoided, and secondary pollution to air is also avoided.

Description

A double-leaf pneumatic swirling parallel combined demisting device and its application

technical field

The invention belongs to the technical field of environmental protection, and relates to a flue gas demisting device at the outlet of an absorption tower in wet flue gas desulfurization technology and its application, in particular to a double-leaf aerodynamic swirling parallel combined demisting device and its application.

Background technique

Among flue gas desulfurization technologies, wet desulfurization technology is the most widely used. Its core equipment is the absorption tower, and the flue gas washed by the absorption tower will contain a large number of liquid droplets, which will be discharged with the flue gas. This not only causes the loss of a large amount of water, but at the same time, the dissolved and suspended particles in the water will also be discharged into the atmosphere together, causing secondary pollution of the air.

In order to reduce the discharge of liquid droplets, the existing technical means is to install a mist eliminator on the top of the absorption tower. Most of the existing demisters are in the form of folded plates, which have a good demisting effect, and the limit particle size can reach about 25 microns. Because of the restriction of secondary entrainment, its working speed cannot be too high, so it is very difficult to further reduce its limiting particle size.

If you want to further improve the defogging effect and reduce the limit particle size, you need to deal with it through combination principles to further increase the flow velocity.

Through searching, no patent publications related to the patent application of the present invention have been found.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a new form of mist eliminator, which works on the principle of pneumatic swirl, improves the working flow rate and reduces the limit particle size, thereby reducing the mist at the outlet of the mist eliminator. The double-leaf pneumatic cyclone parallel combination demister device and its application based on the effect of droplet concentration can be applied to the removal of free liquid droplets contained in flue gas after wet flue gas desulfurization.

The purpose of the present invention is achieved through the following technical solutions:

A double-leaf pneumatic swirl parallel combined defogging device, the device includes one or more than two pneumatic swirl defogging units and a blocking plate, the central axis of the pneumatic swirl defogging unit is set in a vertical direction ;

When there is one pneumatic swirl defogging unit, the outer edges of the top and bottom of the pneumatic swirl defogging unit are connected with blocking plates;

When there are more than two pneumatic swirl defogging units, the pneumatic swirl defogging units are arranged side by side on the same horizontal plane, the central axis of each pneumatic swirl unit is arranged in parallel, and each pneumatic swirl defogger The bottom and the top of the units are sealed and connected together by a blocking plate, and the outer edge of the top and bottom of the outermost pneumatic cyclone demisting unit is connected with a blocking plate.

Moreover, the pneumatic cyclone defogging unit includes an outer cylinder, a deflector, an inner cylinder, an outer guide vane, an inner guide vane, a sealing plate, a tapered section, a diffuser section and a drainage section, and the deflector , the inner cylinder, the tapered section and the expansion section are sequentially arranged in the outer cylinder from bottom to top, the inner cylinder is coaxially arranged with the outer cylinder, and the drainage section is coaxially arranged in the outer cylinder above the expansion section On the body, the deflector is installed obliquely at the bottom of the outer cylinder;

The inner guide vane is installed in the inner cylinder and is composed of a plurality of plane blades, which are arranged circularly symmetrically around the central axis of the inner cylinder, and each plane blade has an included angle with the horizontal direction, and each plane blade is at The cross-sectional direction projection of the inner cylinder can cover the entire cross-section and overlap;

The outer guide vane is installed between the outer cylinder and the inner cylinder, and is composed of a plurality of outer guide vane plane blades. The central axis of the outer cylinder is arranged in a circular symmetry, and each outer guide vane plane blade is clamped with the horizontal direction. Angle, the projection of each outer guide vane plane blade in the cross-sectional direction of the outer cylinder can cover the entire cross-section between the inner cylinder and the outer cylinder, and there is overlap;

The sealing plate is a flat plate or a curved plate, installed at the axis of the inner guide vane, and the sealing plate can make the inner guide vanes form a circular symmetrical arrangement around the sealing plate;

The tapered section is a conical circular tube, which is arranged coaxially with the outer cylinder. The diameter of the tapered section gradually decreases from bottom to top, and the bottom is smoothly connected with the inner wall of the outer cylinder. The diameter of the bottom is the same as that of the outer cylinder. The same, the diameter of the top is the same as that of the diffuser;

The diffuser section is a conical circular tube, which is arranged coaxially with the outer cylinder. The diameter of the diffuser section gradually increases from bottom to top, and the top is smoothly connected with the inner wall of the outer cylinder. The diameter of the top is the same as that of the outer cylinder. The diameters are the same, the diameter of the bottom is the same as the top diameter of the tapered section, and the tapered section and the diffuser section are connected together by a straight pipe 7 arranged coaxially with the outer cylinder;

A drainage section is arranged on the outer cylinder near the top of the outer cylinder, the drainage section includes a water retaining ring and a sump, the inner end of the water retaining ring is coaxially arranged in the inner wall of the outer cylinder, The cross-section of the inner end of the water retaining ring arranged in the inner wall of the outer cylinder is in an inverted L shape, and the outer end of the water retaining ring extends obliquely upwards from the inner end to the outer cylinder through the inner wall of the outer cylinder Outside the body, a curved corner with a circular arc transition is formed outside the outer cylinder and bent to the vertical downward direction. One side of the water retaining ring is connected with the outer cylinder. The other side of the ring is spaced apart from the outer cylinder, and a sump is coaxial with the outer cylinder below the water retaining ring outside the outer cylinder. The diameter of the sump is larger than the maximum diameter of the water retaining ring outside the outer cylinder. Diameter, the water collection tank is used to collect the liquid droplets flowing down from the water retaining ring outside the outer cylinder, and the water collection tank is provided with a drainage device for discharging the liquid collected in the water collection tank.

Moreover, the outer cylinder or the inner cylinder is a straight barrel structure, the length of the outer cylinder is 500mm to 3000mm, and the inner diameter is 100mm to 1000mm; or, the length of the inner cylinder is 200mm to 500mm, and the inner diameter is 50mm to 500mm; Alternatively, the outer cylinder and/or the inner cylinder are made of materials with a low coefficient of friction.

Moreover, the material with a low coefficient of friction is a plastic product.

Moreover, the drainage device is provided on the sump for setting drainage holes or drain pipes on the sump.

Moreover, the outer guide piece, the inner guide piece, the sealing plate, the deflector plate, the tapering section, the flow expansion section, and the drainage section arranged in sequence are arranged in one or more layers to form a series arrangement.

Moreover, the double-leaf pneumatic cyclone parallel combination demisting device is installed in wet flue gas desulfurization equipment.

Moreover, the double-leaf pneumatic cyclone parallel combination demisting device is installed in the absorption tower of the flue gas desulfurization device or in a separate device behind the absorption tower.

The application of the above-mentioned double-leaf pneumatic cyclone parallel combination demisting device in the aspect of removing free liquid droplets contained in the flue gas after wet flue gas desulfurization.

Advantage and positive effect of the present invention are:

1. The device of the present invention utilizes the principle of inertial separation, and at a certain working speed, the small liquid droplets flow to the cylinder wall under the action of inertial centrifugal force. Compared with the traditional folding plate demister, the present invention has a The axial direction is transformed into a partial tangential direction, thereby increasing its working flow rate as a whole, and keeping the axial speed from being too high. Therefore, the limit particle size of the droplets passing through the device is reduced, and the limit particle size of the droplets collected by the device can reach less than 15 microns, thereby achieving the effect of reducing the concentration of droplets at the outlet of the demister and avoiding the loss of water. At the same time, it also avoids secondary pollution of the air.

2. Due to the high flow rate of the device of the present invention, a uniform water film is formed on the inner surface of the barrel, so the device does not have high requirements for cleaning. Compared with the traditional folding plate demister, the intensity of flushing water is reduced and energy is saved.

3. The device of the present invention increases the tangential flow velocity of the outer cylinder due to the enlarged unit diameter, so that the defogging effect is more obvious.

Description of drawings

Fig. 1 is a partial cross-sectional view of the structural connection of the double-blade aerodynamic swirl parallel combination device of the present invention;

Fig. 2 is the enlarged schematic diagram of the structural connection of the pneumatic swirl defogging unit in Fig. 1;

Fig. 3 is an axial schematic diagram of the structural connection of the outer guide vane, the inner guide vane and the sealing plate in Fig. 2 .

Detailed ways

Hereinafter, the present invention will be further described in detail by taking the embodiment of the accompanying drawings as an example. The following embodiments are only descriptive, not restrictive, and cannot limit the protection scope of the present invention.

The structures, connections and methods not described in detail in the patent of the present invention can be understood as common knowledge in the field.

A double-leaf pneumatic swirl parallel combined demister device, as shown in Figure 1, the device includes one or more than two pneumatic swirl demist units 2 and a blocking plate 1, the pneumatic swirl demist unit The central axis is set in the vertical direction;

When there is one pneumatic swirl defogging unit, the outer edges of the top and bottom of the pneumatic swirl defogging unit are connected with a plugging plate, and the pneumatic swirl defogging unit can be installed with the device through the plugging plate The inner walls of the reaction device 3 are sealed and installed together, and the gap between the pneumatic cyclone unit and the inner wall is blocked, so that the flue gas can only pass through the outer cylinder of the double-leaf pneumatic cyclone unit from bottom to top;

When there are more than two pneumatic swirl defogging units, the pneumatic swirl defogging units are arranged side by side on the same horizontal plane, the central axis of each pneumatic swirl unit is arranged in parallel, and each pneumatic swirl defogger The bottom and top of the units are sealed and connected together by the sealing plate, and the outer edge of the top and bottom of the outermost pneumatic cyclone demister unit is connected with a sealing plate, and the outermost pneumatic cyclone demisting unit is connected with a sealing plate. The mist unit can be sealed and installed together with the inner wall of the reaction device where the device is installed through the sealing plate, and the gap between the pneumatic cyclone unit and the inner wall is sealed, so that the flue gas can only flow from the bottom to the top. The inner cylinder of the pneumatic swirl unit passes through.

As shown in Figure 2, the pneumatic swirl defogging unit includes an outer cylinder 4, a deflector 11, an inner cylinder 9, an outer guide vane 10, an inner guide vane 12, a sealing plate 13, a tapered section 8, a diffuser The flow section 6 and the drainage section 5, the deflector, the inner cylinder body, the tapered section and the diffuser section are sequentially arranged in the outer cylinder body from bottom to top, the inner cylinder body and the outer cylinder body are coaxially arranged, and the The drainage section is coaxially arranged on the outer cylinder above the diffuser section, and the deflector is installed obliquely at the bottom of the outer cylinder, and the deflector rectifies the airflow entering the inner guide vane and the outer guide vane;

As shown in Figure 3, the inner guide vane is installed in the inner cylinder and is composed of a plurality of plane blades (not labeled in the figure). There is an included angle with the horizontal direction, and the projection of each plane blade in the cross-section direction of the inner cylinder can cover the entire cross-section and overlap;

As shown in Figure 3, the outer guide vane is installed between the outer cylinder and the inner cylinder, and is composed of a plurality of outer guide vane plane blades (not labeled in the figure), and the central axis of the outer cylinder is arranged in a circular symmetry, each The plane blades of each outer guide vane have an included angle with the horizontal direction, and the projection of each plane blade of the outer guide vane on the cross-sectional direction of the outer cylinder can cover the entire cross-section between the inner cylinder and the outer cylinder, and there is overlap ;

The sealing plate is a flat plate or a curved plate, installed at the axis of the inner guide vane, and the sealing plate can make the inner guide vanes form a circular symmetrical arrangement around the sealing plate;

The tapered section is a conical circular tube, which is arranged coaxially with the outer cylinder. The diameter of the tapered section gradually decreases from bottom to top, and the bottom is smoothly connected with the inner wall of the outer cylinder. The diameter of the bottom is the same as that of the outer cylinder. The same, the diameter of the top is the same as that of the diffuser;

The diffuser section is a conical circular tube, which is arranged coaxially with the outer cylinder. The diameter of the diffuser section gradually increases from bottom to top, and the top is smoothly connected with the inner wall of the outer cylinder. The diameter of the top is the same as that of the outer cylinder. The diameters are the same, the diameter of the bottom is the same as the top diameter of the tapered section, and the tapered section and the diffuser section are connected together by a straight pipe 7 arranged coaxially with the outer cylinder;

A drainage section is arranged on the outer cylinder near the top of the outer cylinder, and the drainage section includes a water retaining ring (not labeled in the figure) and a sump 14, and the inner end 17 of the water retaining ring is coaxial Set in the inner wall of the outer cylinder, the cross-section of the inner end of the water retaining ring arranged in the inner wall of the outer cylinder is in an inverted L shape, and the outer end 15 of the water retaining ring passes through the outer end from the inner end. The inner wall of the cylinder extends obliquely upwards to the outside of the outer cylinder, forming a corner 16 of arc transition outside the outer cylinder and bending to the vertical downward direction. One side of the water retaining ring is connected with the outer cylinder. The other side of the water retaining ring connected to the outer cylinder is set at intervals with the outer cylinder, and a water collecting tank is arranged coaxially with the outer cylinder below the water retaining ring arranged outside the outer cylinder, and the diameter of the water collecting tank is larger than The maximum diameter of the water retaining ring outside the outer cylinder. The sump is used to collect the liquid droplets flowing down from the water retaining ring outside the outer cylinder. The sump is provided with a drainage device for draining the liquid collected in the sump. Drainage, such as drain holes or drainpipes in the sump.

In this embodiment, the outer cylinder or the inner cylinder is a straight barrel structure, the length of the outer cylinder is 500mm to 3000mm, and the inner diameter is 100mm to 1000mm; or, the length of the inner cylinder is 200mm to 500mm, and the inner diameter is 50mm to 500mm; or, the outer cylinder and/or the inner cylinder are made of materials with a low friction coefficient, such as plastic products, which have good anti-adhesion performance and reduce the use of flushing water.

In this embodiment, the outer guide piece, inner guide piece, sealing plate, deflector plate, tapered section, flow expansion section, and drainage section arranged in sequence can be provided with one or more layers to form a series arrangement .

The double-leaf pneumatic swirling parallel combination defogging device of the present invention can be modified according to the load requirements of different work, changing the number of units, setting parameters of deflectors, setting parameters and number of blades, sealing plate form, flow velocity of tapered section, etc., to achieve Different loads, different removal efficiencies and different limit particle sizes.

The method of using the double-leaf pneumatic swirling parallel combination defogging device of the present invention is as follows:

The double-leaf pneumatic swirl defogging parallel combination device of the present invention can be installed in the absorption tower of the flue gas desulfurization device, or installed in a separate device after the absorption tower, or in a separate demisting tower or a reaction device with similar functions. Flue gas flows from bottom to top. The device is applied to equipment for wet flue gas desulfurization, and its function is to remove free liquid droplets contained in flue gas after wet flue gas desulfurization. The device of the present invention enables the device to capture The limiting particle size of the droplets is less than 15 microns.

The working principle of the double-leaf pneumatic swirling parallel combined demisting device of the present invention is as follows:

The flue gas to be processed flows into the outer cylinder and the inner cylinder from bottom to top, and after being rectified by the guide plate, enters the guide vane layer. The flue gas near the center enters the inner cylinder, and the flue gas far away from the center enters the inner cylinder. , and the area between the outer cylinder, respectively through the inner guide vane and the outer guide vane, under the action of the inner guide vane and the outer guide vane, the flue gas forms a rotating updraft, so that the velocity direction of the airflow is transformed into a tangential velocity, Make the liquid droplets in the air flow obtain centrifugal force and move towards the cylinder wall;

The center position of the inner guide vane is provided with a sealing plate. The function of the sealing plate is to close the central area of the inner guide vane, making the flow field more conducive to gas-liquid separation;

The swirling airflow moves upwards and enters the tapering section and the diverging section. The airflow path is narrowed and the flue gas velocity is accelerated, which improves the droplet separation effect and causes some small droplets to coalesce and combine into large-sized droplets. making it easier to remove later. After the above steps, most of the droplets have been removed. If the requirements of the removal efficiency cannot meet the requirements, several sets of inner cylinders, outer guide vanes, inner guide vanes, sealing plates, deflectors, and gradients can be added. Shrinking section, expanding flow section. A drainage section is set near the top outlet of the cylinder, and the sump has a drainage device, which can discharge the liquid therein.

The pneumatic swirl defogging device can be modified according to the load requirements of different work, such as changing the number of units, setting parameters of deflectors, setting parameters and quantity of blades, form of sealing plate, flow rate of tapered section, etc., to achieve different loads and different deflectors. Removal efficiency and different limit particle size purposes.

Claims (9)

1. a double leaf air swirl parallel combination demister, is characterized in that: described device comprises one or more air swirl demisting unit and plugging plate, and the axis of described air swirl demisting unit is that vertical direction is arranged;

When described air swirl demisting unit is one, the top of this air swirl demisting unit and the outer rim of bottom are all connected with plugging plate;

When described air swirl demisting unit is two or more, this air swirl demisting unit is arranged in interval arranged side by side in same level, the axis of each air swirl unit parallels setting, bottom between each air swirl demisting unit is all sealed connected together by plugging plate mutually with top, is all connected with plugging plate at the outermost top of air swirl demisting unit and the outer rim of bottom.

2. double leaf air swirl parallel combination demister according to claim 1, it is characterized in that: described air swirl demisting unit comprises outer cylinder body, deflector, inner barrel, outer stator, interior stator, sealing plate, converging transition, flow-expanding section and draining section, described deflector, inner barrel, converging transition and flow-expanding section are set in turn in outer cylinder body from the bottom to top, described inner barrel and outer cylinder body are coaxially arranged, described draining section is coaxially arranged on the outer cylinder body above flow-expanding section, and described deflector is inclined and mounted on the bottom in outer cylinder body;

Described interior stator is arranged in inner barrel, be made up of multiple plane blade, multiple plane blade is arranged symmetrically with in circle with the central axis of inner barrel, each plane blade all has angle with horizontal direction, whole cross section can all cover in the cross-sectional direction projection of inner barrel by each plane blade, and has overlap;

Described outer stator is arranged between outer cylinder body and inner barrel, be made up of multiple outer stator plane blade, be arranged symmetrically with in circle with the central axis of outer cylinder body, each outer stator plane blade all has angle with horizontal direction, cross section between whole inner barrel and outer cylinder body can all cover in the cross-sectional direction projection of outer cylinder body by each outer stator plane blade, and has overlap;

Described sealing plate is dull and stereotyped or curved slab, is arranged on the axle center place of interior stator, and sealing plate can make interior stator form the symmetrical uniform setting of circle around sealing plate;

Described converging transition is taper pipe, coaxially arranges with outer cylinder body, and converging transition is reduced diameter from bottom to top, and bottom and outer cylinder body inner wall smooth link together, and the diameter of bottom is identical with the diameter of outer cylinder body, and the diameter at top is identical with the diameter of flow-expanding section;

Described flow-expanding section is taper pipe, coaxially arrange with outer cylinder body, flow-expanding section from bottom to top diameter increases gradually, top and outer cylinder body inner wall smooth link together, the diameter at top is identical with the diameter of outer cylinder body, the diameter of bottom is identical with the top diameter of converging transition, and the straight tube coaxially arranged by one and outer cylinder body between described converging transition and flow-expanding section is linked together;

The outer cylinder body of the below at nearly outer cylinder body top arranges draining section, described draining section comprises grade water annulus and a water leg, the inner end of described shelves water annulus is coaxially arranged in outer cylinder body inwall, this cross section being located at the inner end of the shelves water annulus in outer cylinder body inwall is in being inverted L shape, the outer end of this grade of water annulus to be inclined upwardly through outer cylinder body inwall from inner end and to extend to outside outer cylinder body, the bent angle of arc transition is formed and the direction bent towards straight down in outer cylinder body outside, the side of shelves water annulus is connected with outer cylinder body and arranges, opposite side and the outer cylinder body interval of this shelves water annulus arranged that be connected with outer cylinder body are arranged, be arranged at below the shelves water annulus outside outer cylinder body and be coaxially provided with water leg with outer cylinder body, the diameter of this water leg is greater than the maximum gauge of the shelves water annulus outside outer cylinder body, this water leg is for collecting the drop that the shelves water annulus outside outer cylinder body flows down, this water leg is provided with drainage arrangement, liquid for collecting in water leg is discharged.

3. double leaf air swirl parallel combination demister according to claim 2, is characterized in that: described outer cylinder body or inner barrel are straight bucket circular tube structure, and outer cylinder body length is 500mm to 3000mm, and internal diameter is 100mm to 1000mm; Or inner barrel length is 200mm to 500mm, and internal diameter is 50mm to 500mm; Or described outer cylinder body and/or inner barrel adopt the material that coefficient of friction is low.

4. double leaf air swirl parallel combination demister according to claim 3, is characterized in that: the material that described coefficient of friction is low is plastic products.

5. double leaf air swirl parallel combination demister according to claim 2, is characterized in that: described water leg is provided with drainage arrangement for arrange osculum or drainpipe on water leg.

6. the double leaf air swirl parallel combination demister according to any one of claim 2 to 5, it is characterized in that: the described outer guide card arranged that is connected successively, interior guide card, sealing plate, deflector, converging transition, flow-expanding section, draining section arrange one or more layers, form arranged in series.

7. the double leaf air swirl parallel combination demister according to any one of claim 1 to 5, is characterized in that: described double leaf air swirl parallel combination demister is arranged in the equipment of wet process of FGD.

8. double leaf air swirl parallel combination demister according to claim 7, is characterized in that: described double leaf air swirl parallel combination demister to be arranged in flue gas desulfur device absorption tower or in device independent after being arranged on absorption tower.

9. the application in free state drop contained in the flue gas of the double leaf air swirl parallel combination demister as described in any one of claim 1 to 8 after removing wet process of FGD.