CN108686431B - Multistage defogging equipment - Google Patents

Multistage defogging equipment Download PDF

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Publication number
CN108686431B
CN108686431B CN201710235060.5A CN201710235060A CN108686431B CN 108686431 B CN108686431 B CN 108686431B CN 201710235060 A CN201710235060 A CN 201710235060A CN 108686431 B CN108686431 B CN 108686431B
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stage
rectifying
channel
gas
draft tube
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CN108686431A (en
Inventor
何佳
李欣
王海波
金平
王晶
李磊
韩天竹
王昊辰
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Sinopec Dalian Petrochemical Research Institute Co ltd
China Petroleum and Chemical Corp
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China Petroleum and Chemical Corp
Sinopec Dalian Research Institute of Petroleum and Petrochemicals
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D45/00Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces
    • B01D45/04Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces by utilising inertia
    • B01D45/08Separating dispersed particles from gases or vapours by gravity, inertia, or centrifugal forces by utilising inertia by impingement against baffle separators
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2247/00Details relating to the separation of dispersed particles from gases, air or vapours by liquid as separating agent
    • B01D2247/10Means for removing the washing fluid dispersed in the gas or vapours
    • B01D2247/106Means for removing the washing fluid dispersed in the gas or vapours using a structured demister, e.g. tortuous channels

Abstract

The invention discloses a multistage demisting device which comprises a plurality of parallel demisting assemblies, wherein each demisting assembly comprises a multistage gas lift pipe and an outer cylinder, the multistage gas lift pipe is a coaxial gas lift pipe with a plurality of pipe diameters gradually increased from inside to outside, and the multistage gas lift pipe is at least 2 stages; the outer cylinder is arranged on the outer side of the multistage gas lift pipe and is on the same axis with the gas lift pipe; the innermost layer of the multistage gas lift pipe is the first stage, and the top of each stage of gas lift pipe is gradually increased from inside to outside. The circumference of the upper end of each stage of gas lift pipe is respectively and uniformly provided with a plurality of gas outlet rectifying channels, and the rotating direction of the gas outlet rectifying channels of each stage of gas lift pipe is the same as that of the gas inlet rectifying channels of the first stage of gas lift pipe. The multistage demisting device disclosed by the invention is simple in structure, small in pressure drop, not easy to scale, convenient to install, capable of reducing entrainment and effectively realizing gas-liquid separation, and particularly suitable for occasions with large gas flow and high demisting requirements.

Description

Multistage defogging equipment
Technical Field
The invention relates to a gas-liquid separation device, in particular to a multistage demisting device.
Background
Large amount of SO is generated in the production process of industries such as electric power, metallurgy, petrochemical industry and the like2And dust and other harmful substances, which bring serious acid rain hazard and haze weather, is the air pollutant which is currently controlled in China. At present, the wet desulphurization technology is generally adopted in the field of environmental protection to remove harmful substances such as sulfur dioxide in flue gas, namely, alkali liquor is sprayed on the flue gas to absorb or adsorb the harmful substances. However, in the wet desulphurization process, the flue gas desulfurized by the absorption tower has a large number of particle sizesFine droplets of about 10 to 60 μm in which sulfuric acid, sulfate and SO are dissolved2And the like, not only can cause pollution to the atmospheric environment, but also can cause serious corrosion and scaling to subsequent equipment. Thus, when using a wet desulfurization process, the cleaned gas must be demisted prior to exiting the absorber tower, and the demisting step is accomplished by means of a demister.
The defroster generally sets up at the absorption tower top, and when the gas that contains the mist passes through the defroster with certain speed, can collide with defroster inner structure to attach on its surface. Mist on the surface of the inner structure of the demister can be gradually gathered under the action of diffusion and gravity, and after the weight reaches a certain level, the mist can be separated from the inner structure of the demister, so that gas-liquid separation is realized. When the demister causes resistance drop to increase to a preset value due to scaling in the operation process, a backwashing program needs to be started to wash the demister, generally, washing nozzles need to be arranged at the air inlet end and the air exhaust end of the demister, and the gas phase can be seriously carried to the liquid phase to cause liquid entrainment of the gas phase.
Common demisters include a wire mesh demister, a herringbone plate demister, a spiral-flow plate demister and the like. Although the wire mesh demister can separate common mist, the mist is required to be clean, the flow velocity of air flow is small, resistance is reduced greatly, the service cycle is short, and the equipment investment is large. The current demister is generally arranged horizontally, the gas flowing direction of the demister is perpendicular to a wire mesh, when the gas velocity is low, entrained mist is small in inertia, the mist waves in the gas and cannot be removed due to collision contact with the wire mesh, and the gas is easy to generate secondary entrainment to the liquid drops due to the fact that separated liquid drops and the gas phase are in a countercurrent flow direction, so that the gas-liquid separation efficiency is reduced, and the wire mesh demister also has the problems of easy blockage, large pressure drop and the like. The blade type and herringbone demister are internally provided with baffle plates with different directions and different shapes so as to form a small flow channel, increase the demisting effect, and have more complex structure and poor separation effect. The whirl plate defroster is the same with the gaseous flow direction by the separation liquid drop, easily produces the secondary and smugglies secretly, reduces defogging efficiency to the pressure drop is big, and the energy consumption is higher.
The demisting element introduced in CN200410014713.X consists of a baffle plate and a flue gas flow field adjusting block, wherein the baffle plate is fixed on the flue gas flow field adjusting block, and the density and the shape of the baffle plate are changed according to the change of flow field parameters at each position of a flow section, so that the flow section of airflow in an absorption tower is uniformly distributed, and the phenomenon of gas-liquid countercurrent in the drop falling process can not be avoided, namely secondary entrainment is easy to generate.
The defroster that CN200920128824.1 introduced comprises cooler, thick defroster and smart defroster etc. and thick defroster is wave plate or defogging board, and smart defroster is the wire net, and this defroster has changed the shortcoming that traditional defroster liquid droplet flows against the current with the air current direction, has improved defogging efficiency. But this defroster structure is more complicated, and the preparation is difficult, owing to adopted the wire mesh structure, the defroster pressure drop is great, also blocks up relatively easily.
CN203724892U introduces a straight cylindric baffling formula defroster comprises a plurality of defogging subassembly, and every defogging subassembly all includes gas-lift pipe and urceolus, and the circumference of gas-lift pipe is opened has a plurality of seams, is provided with slot and tangential water conservancy diversion wing on the gas-lift pipe circumference that is close to each seam, and the tangential water conservancy diversion wing plays the water conservancy diversion effect, makes the gas flow direction change. The separation of liquid drops and gas is realized through multiple baffling of fluid in the flowing process, the liquid drops with smaller particle size can be effectively removed, and the demisting efficiency is higher. However, after the gas flows through the tangential flow guide wings, the gas direction is still relatively divergent and not concentrated enough, the gas speed is reduced, and the impact force is smaller when the gas collides with the inner wall of the outer barrel, so that the demisting effect is influenced. This defroster mainly relies on the baffling to make gaseous direction change, thereby gaseous and solid wall bumps and realizes gas-liquid separation, and is better to great liquid drop defogging effect, nevertheless is not obvious to the droplet effect, and this defroster structure is more complicated, and the easy scale deposit in space between gas-lift pipe and the tangential water conservancy diversion wing.
US7618472B2 provides a vane type demister comprised of corrugated plates, flat plates, louvers, etc. and defining a plurality of cavities or channels. After the gas-liquid mixture enters the demister, the fluid flow channel is deviated, so that the flow direction of the fluid can be changed for a plurality of times, the speed change is very fast, and the liquid phase is easily separated from the gas phase. In the process of separating the liquid phase from the gas phase, the gas-liquid cross flow can be realized, so that the secondary entrainment effect of the gas phase on liquid drops is greatly reduced, but the technology has a very complicated structure, high processing difficulty and high corresponding processing and manufacturing cost.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a multi-stage demisting device which realizes the separation of liquid drops and gas through the rectification, acceleration and scraping effects of fluid in the flowing process. The demister disclosed by the invention is simple in structure, small in pressure drop, not easy to scale, convenient to install, capable of effectively realizing gas-liquid separation and particularly suitable for occasions with large gas flow and high demisting requirements, and entrainment is reduced.
The multistage demisting device comprises a plurality of parallel demisting assemblies, each demisting assembly comprises a multistage gas lift pipe and an outer cylinder, the multistage gas lift pipe is a coaxial gas lift pipe with a plurality of pipe diameters gradually increased from inside to outside, the multistage gas lift pipe is at least 2 stages, preferably 2-5 stages, the pipe diameter of each stage of gas lift pipe is gradually increased by stages in proportion of 1.1-1.8 times, and preferably the pipe diameters of each stage of gas lift pipe are increased by equal proportions; the outer cylinder is arranged on the outer side of the multistage gas lift pipe and is on the same axis with the gas lift pipe; the innermost layer of each stage of the riser is a first stage, the top of each stage of the riser is gradually raised from inside to outside, the top of each stage of the riser is provided with an upper sealing cover plate, the first stage of the riser is fixed on a tower tray, the bottom of the first stage of the riser is lower than the tower tray by a certain distance, the bottoms of the other stages of the risers are fixedly connected with the first stage of the riser at a position above the tower tray, and the bottom of each stage of the riser is provided with a lower sealing cover plate; the first-stage gas lift pipe is uniformly provided with a plurality of gas inlet rectifying channels on the circumference of the part below the tower tray, the gas inlet rectifying channels are horizontally embedded along the tangential direction of the outer wall of the first-stage gas lift pipe, the side wall I of one side, close to the outer cylinder, of the gas inlet rectifying channel is tangent to the pipe wall of the first-stage gas lift pipe, the other side wall II of the gas inlet rectifying channel is intersected with the pipe wall of the first-stage gas lift pipe, the rotating directions of the gas inlet rectifying channels are the same, the bottom of the gas inlet rectifying channel is flush with the lower cover plate of the first-stage; the circumference of the upper end of each stage of gas lift pipe is respectively and uniformly provided with a plurality of gas outlet rectifying channels, the gas outlet rectifying channels of each stage of gas lift pipe are horizontally embedded along the tangential direction of the outer wall of the gas lift pipe, the side wall I of one side, close to the outer cylinder, of the gas outlet rectifying channel of each stage of gas lift pipe is tangent to the wall of the gas lift pipe, the other side wall II of the gas lift pipe is intersected with the wall of the gas lift pipe, the rotating direction of the gas outlet rectifying channels of each stage of gas lift pipe is the same as that of the gas inlet rectifying channel of the first stage of gas lift pipe, the top of the gas outlet rectifying channel.
In the multistage demisting device, 1-12, preferably 4-8 outlet rectification channels of the riser pipes are arranged, and the wall thickness of the outlet rectification channels of the riser pipes is preferably the same as that of the riser pipes; the number of the gas rectification channels on each stage of the gas risers can be the same or different.
In the multistage demisting device, the length l of the air outlet rectification channel is the length of the side wall II of the air outlet rectification channel, the width w is the maximum horizontal distance between the two side walls of the air outlet rectification channel, and the height h is the maximum vertical distance between the top and the bottom of the air outlet rectification channel; wherein the length l is 2-5 times, preferably 3-4 times of the width w; the section of the air outlet rectification channel is in one or more combinations of a rectangle, an ellipse, a circle, a trapezoid or a semicircle, and the like, and preferably in one or more combinations of a rectangle, an ellipse or a circle. The size of the outlet rectification channel of each stage of the riser is determined by a person skilled in the art according to the actual working condition or design requirement. Generally, the width w and the length l of the outlet rectification channel of each stage of the riser are limited so as not to touch the tube wall of the next stage of the riser, and the length l of the outlet rectification channel of each stage of the riser is preferably gradually increased from inside to outside in a proportion of 1.1 to 1.8 times. The total cross-sectional area of the air outlet rectification channel is 0.2-0.9 times of the cross-sectional area of the first-stage riser, and preferably 0.3-0.6 times of the cross-sectional area of the first-stage riser.
In the multistage demisting device, the tail end of the side wall II of the air outlet rectification channel can be flush with the inner wall of the air lifting pipe or extend into the air lifting pipe for a certain distance m, wherein m is 0.1-0.9 times of the length l, and preferably 0.3-0.6 times. When the tail end of the side wall II of the air outlet rectifying channel is flush with the inner wall of the air lift pipe, the tail end of the bottom of the air outlet rectifying channel is also flush with the inner wall of the air lift pipe; when the side wall II of the air outlet rectifying channel extends into the interior of the air lifting pipe for a certain distance m, the tail end of the bottom of the air outlet rectifying channel is flush with the tail end of the side wall.
In the multistage demisting device, the bottom of the gas outlet rectifying channel of the first stage of gas risers is at a certain distance A from the tower tray, the distance A is 20-200 mm, preferably 40-80 mm, and the bottoms of the gas outlet rectifying channels of the other stages of gas risers are slightly higher than the upper sealing cover plate of the previous stage of gas risers.
In the multistage demisting device, the lower cover plate of the first-stage riser is away from the tower tray by a certain distance B, and the distance B is 1.1-3 times, preferably 1.5-2 times, of the height of the air inlet rectifying channel. The lower sealing cover plate of the second-stage gas lift pipe is lower than the bottom of the gas outlet rectifying channel of the first-stage gas lift pipe by a certain distance, and the distance is preferably 10-50 mm. The lower sealing cover plate of the other gas risers at all levels can be flush with the lower sealing cover plate of the second gas riser, or sequentially lower than the bottom of the gas outlet rectifying channel of the previous gas riser by a certain distance, preferably 10-50 mm.
In the multistage demisting device, the distance between the upper cover plate and the lower cover plate of each stage of the gas lift pipe is the height of each stage of the gas lift pipe.
In the multistage demisting device, 1-12 air inlet rectifying passages are generally arranged, and 2-6 air inlet rectifying passages are preferably arranged. The wall thickness of the inlet rectifying channel is preferably the same as the wall thickness of the draft tube.
In the multistage demisting device, the length e of the air inlet rectifying channel is the length of the side wall II, the width f is the maximum horizontal distance between the two side walls of the air inlet rectifying channel, and the height g is the maximum vertical distance between the top and the bottom of the air inlet rectifying channel; wherein the length e is 1-3 times, preferably 1.2-2 times of the width f; the cross section of the air inlet rectifying channel is in one or more combinations of a rectangle, an ellipse, a circle, a trapezoid or a semicircle, and the like, and preferably in one or more combinations of a rectangle, an ellipse or a circle; the total cross-sectional area of the air inlet rectification channel is the same as the cross-sectional area of the air lifting pipe. The size of the inlet rectifying channel is determined by a person skilled in the art according to actual working conditions or design requirements, and the tail end of the side wall II of the inlet rectifying channel is flush with the inner wall of the riser.
In the multistage demisting device, the top of the air inlet rectifying channel is lower than the tower tray by a distance B, and the bottom of the air inlet rectifying channel is flush with the lower cover plate; the number of inlet rectifying channels may be the same as or different from the number of outlet rectifying channels.
In the multistage demisting device, the first stage gas-raising pipe is hermetically connected with the tower tray, and the diameter of the first stage gas-raising pipe and the aperture ratio of the tower tray can be determined by a person skilled in the art according to the actual working condition or design requirements.
In the multistage demisting device, the air inlet rectifying channel, the air outlet rectifying channel, the upper cover plate, the lower cover plate and the gas rising pipe can be welded together or integrally formed.
In the multistage defogging device, 2-3 circular holes are formed in the lower sealing cover plate of each stage of gas lift pipe except the first stage gas lift pipe and used for discharging coalesced liquid drops in the gas lift pipe, and the diameter of each circular hole is preferably 5-10 mm.
In the multistage demisting device, the outer cylinder is a cylinder or a cone or the combination of the cylinder and the cone, the outer cylinder is divided into an upper section and a lower section, and the diameter D of any section of the lower section of the outer cylinder is 1.1-2 times, preferably 1.3-1.5 times, of the diameter D of the nearest riser on the section; the upper section of the outer cylinder is preferably conical, and the diameter D is 1.5-6 times, preferably 2-3 times of the diameter D1 of the first stage draft tube. The upper edge of the outer barrel is higher than the upper edge of the outmost layer of the riser by a certain distance P, and the distance P is 1-8 times, preferably 2-5 times, of the height of the air outlet rectification channel of the outmost layer of the riser. The lower edge of the outer cylinder is away from the tower tray by a certain distance C, is lower than the lower edge of the first-stage riser gas outlet rectification channel, and is 5-100 mm, preferably 20-50 mm. The total height H of the outer barrel is 2-20 times, preferably 4-10 times, of the height of the first-stage riser outlet rectification channel.
In the multistage defogging device, the inner surface of the outer cylinder is provided with a groove or a bulge. The grooves or projections are parallel to the axis of the outer barrel or may be at an angle to the axis. The cross section of the groove or the bulge can also be in a proper shape such as a rectangle, a triangle or a circle.
In the multistage defogging device, the inner surface of the outer cylinder is preferably provided with a groove with a cross section shape as shown in fig. 6, the cross section of the groove is composed of an arc and a straight line segment, wherein intersection points of the arc and the inner surface circumference of the outer cylinder are respectively made into tangent lines of the arc and the circumference, an included angle between the tangent lines is α degrees to 70 degrees, preferably 10 degrees to 40 degrees, an included angle between the tangent line of the arc and the straight line segment at the intersection point of the arc and the straight line segment is β degrees to 110 degrees, preferably 45 degrees to 90 degrees, the depth Z of the groove is 0.1 to 0.7 times, preferably 0.3 to 0.5 times of the wall thickness of the outer cylinder, and the arc length between the intersection point of the arc and the inner surface circumference of the outer cylinder and the intersection point of the straight line segment and the inner surface circumference of the outer cylinder is 1/80 to 1/6 times of the inner surface circumference of.
In the multistage defogging device of the invention, the thicknesses of the outer cylinder, the air lift pipe, the upper cover plate and the lower cover plate are preferably the same.
In the multistage demisting device, the lower end opening of the outer cylinder can be arranged into a zigzag or wavy structure, so that separated liquid can drip from the inner wall of the outer cylinder in a continuous flow.
The connection parts of the components of the multistage demisting device ensure sealing, and the phenomenon of air leakage is avoided.
The method comprises the steps that when the first stage rectifying channel flows along the inner wall of the first stage rectifying channel, a part of droplets collide with the inner wall of the first stage rectifying channel, so that a plurality of droplets are attached to and coalesce with the inner wall of the first stage rectifying channel, the attached droplets gradually increase, when the gravity generated by a part of the larger droplets exceeds the resultant force of the rising force of gas and the surface tension of liquid, the droplets fall along the surface of the first stage rectifying channel and are separated, the first gas-liquid separation is completed, the other part of the larger droplets continuously flow along the gas, the droplets rotate and flow upwards along the inner wall of the first stage rectifying channel, the gas flow direction after encountering a first stage upper sealing cover plate is changed, a part of the droplets collide with a first stage upper sealing cover plate, so that the second gas-liquid separation is completed, meanwhile, a part of the droplets are converged and collide into larger droplets, and continuously flow along the gas, the droplets enter the first stage outlet rectifying channel of the first stage outlet rectifying channel along the outlet gas outlet channel, and the outlet gas outlet channel, the outlet gas outlet channel is entrained droplets are entrained with the outlet gas outlet channel, the outlet gas outlet channel, the droplets are entrained with the outlet channel, the droplets are entrained and flow into a straight-entrained droplets, the straight-flow channel, the straight-line section of the straight-flow channel, the straight-line section of the straight-flow channel, the straight-flow of the straight-flow channel, the straight-flow of the straight-flow channel.
The multistage demisting device is applied to the absorption tower adopting the wet desulphurization process, the gas velocity entering the first stage of the riser is 3-20m/s, the gas velocity at the outlet of the gas outlet rectifying channel of the outermost riser is 10-40m/s, and the gas velocity at the outlet of the gas outlet rectifying channel of the outermost riser is 1.5-3 times of the gas velocity entering the first stage of the riser.
Compared with the prior art, the multistage demisting device has the following advantages:
1. the lower end of the first-stage gas lift pipe is provided with a lower sealing cover plate, and a plurality of first-stage gas inlet rectifying channels are uniformly arranged in the circumferential direction of the lower end, so that gas directly enters the first-stage gas lift pipe along the tangential direction, the cyclone effect is strengthened, the first gas-liquid separation is completed in the process, and meanwhile, a part of gathered large liquid drops continuously flow along with the gas and flow upwards along the rotation of the inner wall of the gas lift pipe.
2. The upper end of each stage of the riser is provided with an air outlet rectifying channel, the air outlet rectifying channel has a certain length, the original speed direction of the dispersed gas carrying liquid drops is changed into the direction along the air outlet rectifying channel after entering the air outlet rectifying channel, and the speed direction is regular and concentrated; and the total cross section area of the air outlet rectifying channel is smaller than that of the air lifting pipe, and the speed of the gas carrying with liquid drops entering the air outlet rectifying channel is increased due to the reduction of the flow area.
3. The multistage gas lift pipes are used in a combined mode, demisting efficiency is improved, and the multistage gas lift pipe is particularly suitable for occasions with large gas flow and high demisting requirements.
4. The section of the groove on the inner surface of the cylinder is composed of an arc and a straight line segment, when high-speed gas carrying liquid drops flows upwards along the rotation of the inner wall of the outer cylinder, the liquid drops are thrown outwards continuously under the action of inertia force, the liquid drops enter the groove and move along the arc segment in the groove, and due to the included angle α of 5-70 degrees, the liquid drops can continuously move smoothly along the arc surface of the groove until the straight line segment is blocked and then flow downwards along the inner wall of the outer cylinder, and no dead zone exists.
5. Through multistage defogging, reach the effect of defogging high-efficiently, the less liquid drop of particle diameter smuggleing secretly in the effective desorption gas, the defogging is efficient, has reduced the harm to the environment, has played the effect of environmental protection.
6. The gas flow is uniform, the flow resistance is small, and the resistance is reduced.
7. Simple structure, convenient manufacture, difficult blockage and scaling and no need of backwashing.
8. The water-saving effect is good, and the water removed from the gas carrying the liquid drops can be recycled, so that the water consumption is reduced.
Drawings
Fig. 1 is a schematic diagram of a first configuration (with three risers) of the multistage demister of the present invention.
Fig. 2 is a schematic diagram of a second configuration of the multistage demister (with three stages of chimneys) according to the present invention.
Fig. 3 is a schematic cross-sectional view of an intake rectifying passage.
Fig. 4 is a schematic cross-sectional view of a multi-stage demister with outlet rectification channels flush with the inner wall.
Fig. 5 is a schematic cross-sectional view of a multi-stage demister with outlet flow straightening channels extending into the interior of the riser.
FIG. 6 is a schematic view of a groove having a circular arc and a straight line segment in cross section.
Each of the labels in the figure is: 1-an air inlet rectification channel; 2-lower sealing cover plate; 3-a riser; 4-an air outlet rectification channel; 5, sealing the cover plate; 6-outer cylinder; 7-tray, 8-groove or protrusion.
Wherein, 2-1-first-stage lower sealing cover plate; 2-a second-stage lower sealing cover plate; 2-3-third-stage lower sealing cover plate; 3-1-first stage riser; 3-2-second stage draft tube; 3-third stage riser; 4-1-a first-stage air outlet rectification channel; 4-2-a second-stage air outlet rectification channel; 4-3-third stage air outlet rectification channel; 5-1, a first-stage upper sealing cover plate; 5-2-a second-stage upper sealing cover plate; 5-3-a third-stage upper sealing cover plate; 6-1-lower section of outer cylinder; 6-2-upper section of outer cylinder.
Detailed Description
The multistage demister of the invention is further described in detail with reference to the accompanying drawings and examples. The three-stage draft tube is provided for illustration, but the invention is not limited thereto.
The multistage demisting device comprises a plurality of parallel demisting assemblies, each demisting assembly comprises a multistage gas-lift pipe 3 and an outer cylinder 6, the multistage gas-lift pipes are coaxial gas-lift pipes with the pipe diameters gradually increased from inside to outside, the multistage gas-lift pipes are at least 2 stages, preferably 2-5 stages, the pipe diameters of the gas-lift pipes gradually increase by stages by 1.1-1.8 times, and preferably the gas-lift pipes increase by equal proportions; the outer cylinder 6 is arranged on the outer side of the multistage gas lift pipe 3 and is on the same axis with the gas lift pipe 3; the innermost layer of the multistage gas risers 3 is a first stage 3-1, the top of each stage of gas risers is gradually raised from inside to outside, the top of each stage of gas risers is provided with an upper sealing cover plate 5, the first stage of gas risers 3-1 is fixed on a tower tray 7, the bottom of each stage of gas risers is lower than the tower tray 7 by a certain distance, the bottoms of the rest stages of gas risers are fixedly connected with the first stage of gas risers 3-1 at a position above the tower tray 7, and the bottom of each stage of gas risers is provided with a lower sealing cover plate 2; the first-stage gas lift 3-1 is uniformly provided with a plurality of gas inlet rectifying channels 1 on the circumference of the part below a tower tray 7, the gas inlet rectifying channels 1 are horizontally embedded along the tangential direction of the outer wall of the first-stage gas lift 3-1, the side wall I of one side of the gas inlet rectifying channel 1, which is close to an outer cylinder 6, is tangent to the pipe wall of the first-stage gas lift 3-1, the other side wall II is intersected with the pipe wall of the first-stage gas lift 3-1, the rotating directions of the gas inlet rectifying channels 1 are the same, the bottom of the gas inlet rectifying channel 1 is flush with a lower sealing cover plate 2-1 of the first-stage gas lift 3-1, and the top; the circumference of the upper end of each stage of the gas lift is respectively and uniformly provided with a plurality of gas outlet rectifying channels 4, the gas outlet rectifying channels 4 of each stage of the gas lift are horizontally embedded along the tangential direction of the outer wall of the gas lift 3, the side wall I of one side, close to the outer cylinder 6, of the gas outlet rectifying channel 4 of each stage of the gas lift is tangent to the wall of the gas lift, the other side wall II of the gas lift is intersected with the wall of the gas lift, the rotating direction of the gas outlet rectifying channel 4 of each stage of the gas lift is the same as that of the gas inlet rectifying channel 1 of the first stage of the gas lift 3-1, the top of the gas outlet rectifying channel 4 of each stage of.
In the multistage demisting device, 1-12, preferably 4-8 outlet rectification channels 4 of each stage of the riser are arranged, and the wall thickness of the outlet rectification channels 4 of each stage of the riser is preferably the same as that of the riser; the number of the outlet rectifying channels 4 on each stage of the draft tube can be the same or different.
In the multistage demisting device, the length l of the air outlet rectification channel 4 is the length of the side wall II of the air outlet rectification channel 4, the width w is the maximum horizontal distance between the two side walls of the air outlet rectification channel 4, and the height h is the maximum vertical distance between the top and the bottom of the air outlet rectification channel 4; wherein the length l is 2-5 times, preferably 3-4 times of the width w; the cross section of the air outlet rectification channel 4 is in one or a combination of several of rectangle, ellipse, circle, trapezoid or semicircle, and preferably in one or a combination of several of rectangle, ellipse or circle. The size of the outlet rectification channel 4 of each stage of the riser is determined by those skilled in the art according to actual working conditions or design requirements. Generally, the width w and the length l of the outlet rectifying channel 4 of each stage of the riser are limited so as not to touch the tube wall of the next stage of the riser, and the length l of the outlet rectifying channel of each stage of the riser is preferably gradually increased from inside to outside in a proportion of 1.1 to 1.8 times. The total cross-sectional area of the air outlet rectification channel 4 is 0.2-0.9 times of the cross-sectional area of the first-stage draft tube 3-1, and preferably 0.3-0.6 times of the cross-sectional area of the first-stage draft tube 3-1.
In the multistage demisting device, the tail end of the side wall II of the air outlet rectification channel 4 can be flush with the inner wall of the air lifting pipe or extend into the air lifting pipe for a certain distance m, wherein m is 0.1-0.9 times of the length l, and preferably 0.3-0.6 times. When the tail end of the side wall II of the air outlet rectifying channel 4 is flush with the inner wall of the air lift tube, the tail end of the bottom of the air outlet rectifying channel 4 is also flush with the inner wall of the air lift tube; when the side wall II of the air outlet rectifying channel 4 extends into the interior of the air rising pipe for a certain distance m, the tail end of the bottom of the air outlet rectifying channel 4 is flush with the tail end of the side wall.
In the multistage demisting device, the bottom of the air outlet rectifying channel 4-1 of the first stage air lift 3-1 is at a certain distance A from the tower tray 7, the distance A is 20-200 mm, preferably 40-80 mm, and the bottoms of the air outlet rectifying channels 4 of the other stages of air lifts are slightly higher than the upper cover plate 5 of the previous stage air lift.
In the multistage demisting device, a certain distance B is reserved between a lower sealing cover plate 2-1 of a first-stage riser 3-1 and a tower tray 7, and the distance B is 1.1-3 times, preferably 1.5-2 times, of the height of an air inlet rectifying channel 1. The lower sealing cover plate 2-2 of the second-stage gas lift pipe 3-2 is lower than the bottom of the gas outlet rectifying channel 4-1 of the first-stage gas lift pipe 3-1 by a certain distance, and the distance is preferably 10-50 mm. The lower sealing cover plate of the other gas risers at all levels can be flush with the lower sealing cover plate of the second gas riser, or sequentially lower than the bottom of the gas outlet rectifying channel of the previous gas riser by a certain distance, preferably 10-50 mm.
In the multistage demisting device, the distance between the upper cover plate 5 and the lower cover plate 2 of each stage of the air draft tube is the height of each stage of the air draft tube.
In the multistage demisting device, 1-12 air inlet rectifying passages 1 are generally arranged, and 2-6 air inlet rectifying passages are preferably arranged. The wall thickness of the inlet rectifying channel 1 is preferably the same as the wall thickness of the draft tube.
In the multistage demisting device, the length e of the air inlet rectifying channel 1 is the length of the side wall II, the width f is the maximum horizontal distance between the two side walls of the air inlet rectifying channel 1, and the height g is the maximum vertical distance between the top and the bottom of the air inlet rectifying channel 1; wherein the length e is 1-3 times, preferably 1.2-2 times of the width f; the cross section of the air inlet rectifying channel 1 is in one or more combinations of rectangle, ellipse, circle, trapezoid or semicircle, and preferably in one or more combinations of rectangle, ellipse or circle; the total cross-sectional area of the inlet rectifying passage 1 is the same as the cross-sectional area of the draft tube 3. The size of the inlet rectifying channel 1 is determined by those skilled in the art according to the actual working condition or design requirement, and the tail end of the side wall II of the inlet rectifying channel 1 is flush with the inner wall of the riser 3.
In the multistage demisting device, the top of the air inlet rectifying channel 1 is lower than the tower tray 7 by a distance B, and the bottom of the air inlet rectifying channel 1 is flush with the lower cover plate 2; the number of inlet fairing passages 1 and the number of outlet fairing passages 4 can be the same or different.
In the multistage demisting device, the first-stage gas-raising pipe 3-1 is hermetically connected with the tower tray 7, and the diameter of the first-stage gas-raising pipe 3-1 and the aperture ratio of the tower tray 7 can be determined by a person skilled in the art according to actual working conditions or design requirements.
In the multistage demisting device, the air inlet rectifying channel 1, the air outlet rectifying channel 4, the upper cover plate 5, the lower cover plate 2 and the gas lift pipe 3 can be welded together or integrally formed.
In the multistage demisting device, 2-3 circular holes are formed in the lower cover plate 2 of each stage of the gas rising pipe except for the first stage gas rising pipe 3-1 and used for discharging coalesced liquid drops in the gas rising pipe 3, and the diameter of each circular hole is preferably 5-10 mm.
In the multistage defogging device, the outer cylinder 6 is a cylinder or a cone or the combination of the cylinder and the cone, the outer cylinder 6 is divided into an upper section and a lower section, the diameter D of any section of the lower section outer cylinder 6-1 is 1.1-2 times, preferably 1.3-1.5 times, of the diameter D of the nearest gas riser 3 on the section; the upper section of the outer cylinder 6-2 is preferably conical, and the diameter D is 1.5 to 6 times, preferably 2 to 3 times, the diameter D1 of the first stage draft tube 3-1. The upper edge of the outer barrel 6 is higher than the upper edge of the outmost layer riser 3 by a certain distance P, and the distance P is 1-8 times, preferably 2-5 times, of the height of the outmost layer riser air outlet rectification channel 4. The lower edge of the outer cylinder 6 is away from the tower tray 7 by a certain distance C, is lower than the lower edge of the air outlet rectification channel of the first-stage riser 3-1, and is 5-100 mm, preferably 20-50 mm. The total height H of the outer cylinder 6 is 2-20 times, preferably 4-10 times, of the height of the air outlet rectifying channel 4-1 of the first-stage ascending pipe 3-1.
In the multistage defogging device of the invention, the inner surface of the outer cylinder 6 is provided with a groove or a bulge 8. The grooves or projections 8 are parallel to the axis of the outer barrel 6 or may be at an angle to the axis. The cross section of the groove or the protrusion 8 can also be in a suitable shape such as a rectangle, a triangle or a circle.
In the multistage defogging device, the inner surface of the outer cylinder 6 is preferably provided with the groove 8 with the cross section shape shown in FIG. 6, the cross section of the groove 8 is composed of an arc and a straight line segment, wherein the intersection points of the arc and the inner surface circumference of the outer cylinder 6 are respectively made into tangent lines of the arc and the circumference, the included angle between the tangent lines is α degrees to 70 degrees, preferably 10 degrees to 40 degrees, the included angle between the tangent line of the arc and the straight line segment at the intersection point of the arc and the straight line segment is β degrees to 110 degrees, preferably 45 degrees to 90 degrees, the depth Z of the groove 8 is the shortest distance from the intersection point of the arc and the straight line segment to the inner surface circumference of the outer cylinder 6 is 0.1 to 0.7 times, preferably 0.3 to 0.5 times of the wall thickness of the outer cylinder 6, and the arc length between the intersection point of the arc and the inner surface circumference of the outer cylinder 6 is 1/80 to 1/6 of the.
Example one
100000Nm for purifying flue gas in wet washing tower3The apparent water concentration is 10-15 g/Nm3After demisting by the present invention, the concentration of the apparent water in the exhaust gas<0.5g/Nm3And the demisting efficiency is more than or equal to 95 percent.

Claims (8)

1. A multistage demisting device comprises a plurality of parallel demisting assemblies, and is characterized in that each demisting assembly comprises a multistage draft tube and an outer cylinder, the multistage draft tube is a coaxial draft tube with a plurality of gradually-increased tube diameters from inside to outside, the multistage draft tube is at least 2 stages, the gradually-increased tube diameter ratio of each stage of draft tube is 1.1-1.8 times, the outer cylinder is arranged on the outer side of the multistage draft tube and is on the same axis with the draft tube, the innermost layer draft tube of the multistage draft tube is a first stage draft tube, the top of each stage of draft tube is gradually increased from inside to outside, an upper sealing cover plate is arranged at the top of each stage of draft tube, the first stage draft tube is fixed on a tower tray, the bottom of each stage of draft tube is lower than the tower tray by a certain distance, the bottom of each stage of draft tube is fixedly connected with the first stage of draft tube at a position above the tower tray, a lower sealing cover plate is arranged at the bottom of each stage of the draft tube, a plurality of air inlet and outlet rectifying passages are uniformly arranged on the circumference of the lower portion of the tower tray, the first stage of the draft tube, the air inlet and outlet passages are horizontally embedded in the tangent direction of the outer cylinder, the first stage of the draft tube, the rectifying passages are arranged from the tangent line section of the first stage of the draft tube, the rectifying cover plate is from the outer cylinder, the rectifying cover plate, the rectifying passage, the rectifying cover plate is from the rectifying cover plate, the rectifying cover plate is from the rectifying passage, the rectifying cover plate, the rectifying groove is from the inner surface of the rectifying groove, the rectifying groove is from the rectifying groove, the rectifying groove is from the rectifying groove, the rectifying groove is from the rectifying groove, the rectifying groove.
2. The multi-stage mist elimination apparatus of claim 1, wherein: 4-8 air outlet rectification channels of the air risers at each stage are arranged.
3. The multi-stage mist elimination apparatus of claim 1, wherein: the length l of the air outlet rectification channel is the length of the side wall II of the air outlet rectification channel, the width w is the maximum horizontal distance between the two side walls of the air outlet rectification channel, and the height h is the maximum vertical distance between the top and the bottom of the air outlet rectification channel; wherein the length l is 2-5 times of the width w; the section of the air outlet rectification channel is in one or a combination of more of a rectangle, an ellipse, a circle, a trapezoid or a semicircle; the width w and length l of the air outlet rectifying channel of each stage of air-lift pipe are limited so as not to contact the pipe wall of the next stage of air-lift pipe.
4. The multi-stage mist elimination apparatus of claim 1, wherein: the tail end of the side wall II of the air outlet rectification channel is flush with the inner wall of the air lifting pipe or extends into the air lifting pipe for a certain distance m, wherein m is 0.1-0.9 time of the length l; when the tail end of the side wall II of the air outlet rectifying channel is flush with the inner wall of the air lift pipe, the tail end of the bottom of the air outlet rectifying channel is also flush with the inner wall of the air lift pipe; when the side wall II of the air outlet rectifying channel extends into the interior of the air lifting pipe for a certain distance m, the tail end of the bottom of the air outlet rectifying channel is flush with the tail end of the side wall.
5. The multi-stage mist elimination apparatus of claim 1, wherein: a certain distance A is reserved between the bottom of an air outlet rectification channel of the first-stage air rising pipe and the tower tray, and the distance A is 20-200 mm; the lower sealing cover plate of the first stage of the riser is at a certain distance B from the tower tray, the distance B is 1.1-3 times of the height of the air inlet rectifying channel, the lower sealing cover plate of the second stage of the riser is lower than the bottom of the air outlet rectifying channel of the first stage of the riser by a certain distance, and the lower sealing cover plates of the other stages of the risers are flush with the lower sealing cover plate of the second stage of the riser or are sequentially lower than the bottom of the air outlet rectifying channel of the previous stage of the riser by a certain distance.
6. The multi-stage mist elimination apparatus of claim 1, wherein: 2-6 air inlet rectifying channels are arranged; the length e of the air inlet rectifying channel is the length of the side wall II, the width f is the maximum horizontal distance between the two side walls of the air inlet rectifying channel, and the height g is the maximum vertical distance between the top and the bottom of the air inlet rectifying channel; wherein the length e is 1-3 times of the width f; the cross section of the air inlet rectifying channel is in one or a combination of more of a rectangle, an ellipse, a circle, a trapezoid or a semicircle; the total cross-sectional area of the air inlet rectification channel is the same as the cross-sectional area of the first stage gas lift pipe.
7. The multi-stage mist elimination apparatus of claim 1, wherein: the outer cylinder is a cylinder or a cone or the combination of the cylinder and the cone, the outer cylinder is divided into an upper section and a lower section, and the diameter D of any section of the lower section of the outer cylinder is 1.1-2 times of the diameter D of the riser closest to the section; the upper section outer cylinder is conical, and the diameter D is 1.5-6 times of the diameter D1 of the first stage draft tube; the upper edge of the outer cylinder is higher than the upper edge of the outermost layer of the riser by a certain distance P, and the distance P is 1-8 times of the height of the outlet rectification channel of the outermost layer of the riser; the lower edge of the outer cylinder is away from the tower tray by a certain distance C, is lower than the lower edge of the first-stage riser gas outlet rectification channel, and is 5-100 mm; the total height H of the outer barrel is 2-20 times of the height of the air outlet rectifying channel of the first-stage ascending pipe.
8. Use of a multistage mist elimination apparatus as defined in any one of claims 1 to 7 in an absorption tower employing a wet desulfurization process.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102125895A (en) * 2011-01-11 2011-07-20 于晓林 Cyclone
CN102872655A (en) * 2012-09-21 2013-01-16 兰州节能环保工程有限责任公司 Gas-liquid separating device
CN203342552U (en) * 2013-07-09 2013-12-18 刘英聚 Settler-free two-stage cyclone series gas-solid separation equipment
CN104606963A (en) * 2013-11-05 2015-05-13 中国石油化工股份有限公司 Straight cylinder-shaped flow baffling type demister

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1020531C2 (en) * 2002-05-03 2003-11-04 Spark Technologies And Innovat Device and system for separating a mixture.
GB2462210B (en) * 2006-06-16 2010-12-22 Cameron Int Corp Separator and method of separation
RU2344868C1 (en) * 2007-07-12 2009-01-27 Общество с ограниченной ответственностью "Проектно-технологическое бюро проектно-строительного объединения Волгоградгражданстрой" Vertical dust catcher
CN204121887U (en) * 2014-10-10 2015-01-28 石家庄工大化工设备有限公司 High-efficiency foam remover
CN204638380U (en) * 2015-05-05 2015-09-16 谢娟 A kind of cyclone dust removal device of duster for grain

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102125895A (en) * 2011-01-11 2011-07-20 于晓林 Cyclone
CN102872655A (en) * 2012-09-21 2013-01-16 兰州节能环保工程有限责任公司 Gas-liquid separating device
CN203342552U (en) * 2013-07-09 2013-12-18 刘英聚 Settler-free two-stage cyclone series gas-solid separation equipment
CN104606963A (en) * 2013-11-05 2015-05-13 中国石油化工股份有限公司 Straight cylinder-shaped flow baffling type demister

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