CN104984597B - A kind of air swirl parallel combination demister and application - Google Patents

Abstract

The invention relates to a pneumatic cyclone parallel combined defogging device. The device includes one or more than two pneumatic cyclone demister units and a blocking plate. The central axis of the pneumatic cyclone demist unit is in the vertical direction. It is provided that the pneumatic cyclone defogging unit includes a cylinder body, guide vanes, sealing plates, guide plates, a tapered section, a diffuser section and a drainage section. Because the device of the present invention is provided with one or more than two pneumatic swirling demisting units and blocking plates, the working flow rate is improved, the limit particle size is reduced, and the limit particle size of the liquid droplets captured by the device can reach less than 15 microns. In this way, the effect of reducing the droplet concentration at the outlet of the demister is achieved, avoiding the loss of water, and at the same time, avoiding the secondary pollution of the air.

Description

A pneumatic cyclone parallel combination defogging 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 pneumatic cyclone 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 air pollution.

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 pneumatic cyclone parallel combination demister device 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 pneumatic cyclone parallel combination demisting device, the device includes one or more than two pneumatic cyclone demisting units and a blocking plate, the central axis of the pneumatic cyclone demisting unit 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 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 a cylinder, a guide plate, a guide vane, a sealing plate, a tapered section, a diffuser section and a drainage section, and the guide plate, the guide vane, the tapered section and the The diffuser section is sequentially arranged in the cylinder from bottom to top, the drainage section is coaxially arranged on the cylinder above the diffuser section, and the deflector is installed obliquely at the bottom of the cylinder;

The guide vanes are composed of a plurality of plane blades, which are arranged circularly symmetrically with the center line of the cylinder, each plane blade has an included angle with the horizontal direction, and each plane blade is at the cross-section of the cylinder The projections in all directions can cover the entire cross-section and overlap;

The sealing plate is a flat plate or a curved plate, and the sealing plate is installed at the axis of the guide vane;

The tapered section is a conical circular tube, which is arranged coaxially with the 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 cylinder. The diameter of the bottom is the same as that of the cylinder, and the top The diameter is the same as that of the diffuser section;

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

A drainage section is set on the cylinder below the top of the 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 cylinder, and the water retaining ring is arranged on the inner wall of the cylinder. The cross-section of the inner end of the water-retaining ring in the inner wall of the cylinder is an inverted L-shape, and the outer end of the water-retaining ring passes through the inner wall of the cylinder from the inner end and extends upwards to the outside of the cylinder. Form the corner of the arc transition and bend to the vertical downward direction, one side of the water retaining ring is connected to the cylinder, and the other side of the water retaining ring connected to the cylinder is connected to the cylinder Set at intervals, set under the water-retaining ring outside the cylinder and coaxially with the cylinder, there is a sump. The diameter of the sump is larger than the maximum diameter of the water-retaining ring outside the cylinder. Drain the liquid collected in the sump.

Moreover, the cylinder body is a straight barrel and circular tube structure with a length of 500 mm to 3000 mm, an inner diameter of 100 mm to 1000 mm, a smooth inner wall, and a material with a low friction coefficient.

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 guide blades, sealing plate, guide plate, tapered section, diffuser section and drainage section arranged in sequence are arranged in one or more layers, forming a series arrangement.

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

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

The application of the pneumatic cyclone parallel combination demisting device mentioned above 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.

Description of drawings

Fig. 1 is a partial cross-sectional view of the structural connection of the pneumatic cyclone 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 between the guide vane and the sealing plate in Fig. 2 .

detailed description

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 pneumatic cyclone parallel combination demisting device, as shown in Figure 1, the device includes one or more than two pneumatic cyclone demisting units 2 and blocking plates 3, the middle of the pneumatic cyclone demisting unit The 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 1 are sealed and installed together, so that the flue gas can only pass through the cylinder of the pneumatic cyclone demisting 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 blocking plate, so that the smoke can only pass through the cylinder of the pneumatic cyclone demister unit from bottom to top.

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

As shown in Figure 3, the guide vanes are composed of a plurality of plane vanes 16, which are arranged circularly symmetrically with the center line of the cylinder, and each plane vane has an included angle with the horizontal direction, and each plane The projection of the blades in the cross-section direction of the cylinder can cover the entire cross-section and overlap;

The sealing plate is a flat plate or a curved plate, and the sealing plate is installed at the axis of the guide vane, so that a plurality of plane blades form a circularly symmetrical uniform distribution around the sealing plate, and the function of the sealing plate is to close the central area of the guide vane. Make the flow field more conducive to gas-liquid separation;

The tapered section is a conical circular tube, which is arranged coaxially with the 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 cylinder. The diameter of the bottom is the same as that of the cylinder, and the top The diameter is the same as that of the diffuser section;

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

A drainage section is set on the cylinder below the top of the cylinder, and the drainage section includes a water retaining ring (not labeled in the figure) and a sump 12, and the inner end 15 of the water retaining ring is coaxially arranged on the In the inner wall of the cylinder, the cross-section of the inner end of the water retaining ring arranged in the inner wall of the cylinder is in an inverted L shape, and the outer end 13 of the water retaining ring is inclined upwards from the inner end through the inner wall of the cylinder Extending to the outside of the cylinder, a curved corner 14 with a circular arc transition is formed outside the cylinder and bent in a vertical downward direction. One side of the water blocking ring is connected to the cylinder, and the retaining The other side of the water ring is spaced apart from the cylinder, and a sump is arranged under the water retaining ring outside the cylinder coaxially with the cylinder. The diameter of the sump is larger than the maximum diameter of the water retaining ring outside the cylinder. The sump is used to collect the liquid droplets flowing down from the water retaining ring outside the cylinder. The sump is provided with a drainage device for discharging the liquid collected in the sump. For example, a drainage hole or a drain pipe is provided on the sump. .

In this embodiment, the cylinder body is a straight barrel structure with a length of 500 mm to 3000 mm, an inner diameter of 100 mm to 1000 mm, and a smooth inner wall. Materials with a low friction coefficient, such as plastic products, have good anti-adhesion performance. Reduce rinse water usage.

In this embodiment, the sequentially connected guide vanes, sealing plates, guide plates, tapered sections, diffuser sections and drainage sections can be arranged in one or more layers according to actual needs to form a series arrangement.

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.

The pneumatic swirl defogging device can be made of materials with low friction coefficient, such as plastic products, which have good anti-adhesion performance and reduce the use of flushing water.

The method of using the pneumatic cyclone parallel combination demisting device of the present invention is as follows:

The pneumatic swirling parallel combination demisting device of the present invention can be installed in the absorption tower of the flue gas desulfurization device, or in a separate device behind the absorption tower, or in a separate demisting tower or a reaction device 1 with similar functions, and the smoke The gas flows from bottom to top. The device is used in wet flue gas desulfurization equipment. Its function is to remove free liquid droplets contained in the flue gas after wet flue gas desulfurization. The limiting particle size of the droplets is less than 15 microns.

The working principle of the pneumatic cyclone parallel combination demister device of the present invention is as follows:

The flue gas to be processed enters the cylinder from bottom to top, passes through the rectification of the guide plate, and enters the guide vane segment. Under the action of the guide vane, a rotating upward airflow is formed, so that the velocity direction of the airflow is transformed into a tangential velocity. The liquid droplets in the air flow obtain centrifugal force and move towards the wall of the cylinder. The central position of the guide vane is provided with a sealing plate, and the function of the sealing plate is to close the central area of the guide vane, so that the flow field is 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. Therefore, it is easier to be removed later. After the above steps, most of the droplets have been removed. If the requirement of removal efficiency cannot meet the requirements, several groups of guide vanes, sealing plates, guide plates, tapered sections, and diffuser sections can be added. A drainage section is set near the top outlet of the cylinder body, and the sump has a drainage device, and the liquid collected in the sump can be discharged through the setting of the drainage hole and the drain pipe.

Claims (8)

1. an air swirl parallel combination demister, it is characterised in that: described device includes one or more gas Dynamic vortex-flow and defrosting unit and plugging plate, 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 setting There is plugging plate；

When described air swirl demisting unit is two or more, this air swirl demisting unit in same level between side by side Every setting, the parallel setting in axis of each air swirl unit, the bottom between each air swirl demisting unit All it is sealed connected together mutually by plugging plate with top, outside the top and bottom of outermost air swirl demisting unit Edge is all connected with being provided with plugging plate；

Described air swirl demisting unit includes cylinder, deflector, guide vane, sealing plate, converging transition, flow-expanding section and draining Section, described deflector, guide vane, converging transition and flow-expanding section are set in turn in cylinder from the bottom to top, and described draining section is coaxial Being arranged on the cylinder above flow-expanding section, described deflector is inclined and mounted on the bottom in cylinder；

Described guide vane is made up of multiple plane blades, the plurality of plane blade with the circularly symmetric layout of center line of cylinder, Each plane blade all has angle with horizontal direction, and each plane blade all can be by whole in the projection of the cross-sectional direction of cylinder Individual cross section all covers, and has overlap；

Described sealing plate is flat board or curved slab, and this sealing plate is arranged at the axle center of guide vane；

Described converging transition is taper pipe, is coaxially disposed with cylinder, converging transition reduced diameter from bottom to top, bottom and cylinder Inner wall smooth links together, and the diameter of bottom is identical with the diameter of cylinder, and the diameter at top is identical with the diameter of flow-expanding section；

Described flow-expanding section is taper pipe, is coaxially disposed with cylinder, and flow-expanding section diameter from bottom to top is gradually increased, top and cylinder Inner wall smooth links together, and the diameter at top is identical with the diameter of cylinder, the top diameter phase of the diameter of bottom and converging transition With, the straight tube being coaxially disposed with cylinder by between described converging transition and flow-expanding section links together；

Arranging draining section on the cylinder of the lower section at nearly cylinder top, described draining section includes dash annulus and water leg, described The inner end of dash annulus is coaxially disposed in cylinder inboard wall, the cross section of the inner end of the dash annulus being located in cylinder inboard wall In inversed l-shaped, the outer end of this dash annulus is inclined upwardly from inner end extends to outside cylinder, outside cylinder through cylinder inboard wall Portion forms the bent angle of arc transition and bends towards vertically downward direction, and the side of dash annulus is connected with cylinder setting, this with Cylinder is connected opposite side and the cylinder interval setting of the dash annulus arranged, with cylinder below the dash annulus being arranged at outside cylinder Body is coaxially provided with water leg, and the diameter of this water leg is more than the maximum gauge of the dash annulus outside cylinder, and this water leg is provided with Drainage arrangement, discharges for the liquid will collected in water leg.

Air swirl parallel combination demister the most according to claim 1, it is characterised in that: described cylinder is straight bucket circle Tubular construction, a length of 500mm to 3000mm, internal diameter is 100mm to 1000mm, inner wall smooth, uses the material that coefficient of friction is low.

Air swirl parallel combination demister the most according to claim 2, it is characterised in that: described coefficient of friction is low Material is plastic products.

Air swirl parallel combination demister the most according to claim 1, it is characterised in that: described water leg is provided with Drainage arrangement is the osculum or drainpipe arranged on water leg.

5. according to the air swirl parallel combination demister described in any one of Claims 1-4, it is characterised in that: described depend on Secondary guide vane, sealing plate, deflector, converging transition, flow-expanding section and the draining section arranged that be connected is respectively provided with one or more layers, shape Become arranged in series.

6. according to the air swirl parallel combination demister described in any one of Claims 1-4, it is characterised in that: described gas Dynamic eddy flow parallel combination demister is arranged in the equipment of wet process of FGD.

Air swirl parallel combination demister the most according to claim 6, it is characterised in that: described air swirl is in parallel After combining in demister is arranged on flue gas desulfurization device absorptive tower or being arranged on absorption tower in single device.

8. the air swirl parallel combination demister as described in any one of claim 1 to 7 is after removing wet process of FGD Flue gas in contained free state drop aspect in application.