A separation system and a cyclone flue gas purifier

Abstract

The present invention provides a separation system, which relates to the technical field of flue gas purification. The separation system includes at least one set of separation blocks. The separation blocks are arranged on the inner wall of the outer shell of the separation system. The separation blocks are structures protruding from the inner wall of the outer shell of the separation system. The separation blocks in each group are open curves. The separation blocks are used to block the droplets in the airflow to achieve impact interception. Since the separation is an unclosed annular structure, when the airflow impacts the separation blocks, the airflow does not forcibly convert to the tangential velocity in a way that completely loses the axial velocity, but continues to move forward in a way that partially deviates from the gas flow direction, reducing the disturbance of the flow field in a larger range. The fluid that has entered the capture area is not affected. Under the condition that the capture efficiency of the retaining ring of the same length is basically maintained, the swirl is reduced, and at the same time, the pressure drop is smaller. By reasonably arranging the separation blocks, the present invention can obtain a higher removal efficiency under a pressure drop lower than the original one.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas purification, and more particularly to a separation system. In addition, the present invention also relates to a cyclone flue gas purifier. Background Art

[0002] Air pollution has had an increasingly serious impact on people's production and life. Reducing the emission of flue gas pollutants and improving the level of clean production have become urgent problems to be solved in various industrial fields. In the limestone-gypsum wet flue gas desulfurization system of coal-fired power plants, the demister is a key device.

[0003] A cyclone flue gas purifier is a device that uses the centrifugal force generated by rotational motion to separate and capture dust in the air. The working principle of the cyclone flue gas purifier is that the flue gas entering the cyclone impeller will deflect a certain angle under the guidance of the cyclone plate, generally 25° - 30°. The movement of the flue gas can be decomposed into an axial velocity and a tangential velocity. The coarse mist particles in the flue gas directly impact the cyclone plate for capture and then are slowly thrown onto the wall of the cyclone demister. The fine mist entrained in the flue gas is pushed to the inner wall of the demister by the centrifugal force and is captured during continuous rotation and forward movement.

[0004] The conventional retaining ring has a good interception effect on the droplets on the side wall, etc., but it disturbs the flow field greatly and has an obvious swirl elimination effect. Most of the droplets are intercepted by impact instantaneously within a very short time of contacting the retaining ring, and this part of the fluid is forced to change to the tangential velocity in a way that completely loses the axial velocity, and the forward direction of the fluid is restricted to the cross-section of the retaining ring. However, behind the retaining ring, due to the existence of a physical wall (physical segmentation), this part of the tangential velocity is not successfully transmitted to the rear of the retaining ring, and the overall swirling state of the fluid behind the retaining ring is instead segmented and chaotic, forming a de facto swirl elimination effect.

[0005] For those skilled in the art, how to reduce the blockage of the air flow is a technical problem that needs to be solved at present. Summary of the Invention

[0006] The present invention provides a separation system, which uses non-closed separation blocks to reduce the blockage of the air flow. The specific solution is as follows:

[0007] A separation system includes at least one group of separation blocks, and the separation blocks protrude from the inner wall of the separation system housing. The separation blocks in each group are open curves; the separation blocks are used to block the droplets in the air flow to achieve impact interception.

[0008] Optionally, the total overlap rate of all the separation blocks provided in the separation system housing in the axial direction projection is 80 - 500%.

[0009] Optionally, along the axial direction of the separation system housing, the normal height of each separation block gradually changes from the inlet to the outlet.

[0010] Optionally, the separation block is threaded;

[0011] The number of thread turns of a single separation block is 1 - 2 turns; the pitch is 0.5 - 2D, where D is the diameter of the outer shell of the separation system.

[0012] Optionally, the normal height of the separation block is 2 - 8 mm.

[0013] Optionally, the number of the separation blocks is greater than three groups, and the axial spacing between two adjacent groups of the separation blocks gradually increases from the inlet to the outlet.

[0014] Optionally, the normal height of each separation block gradually decreases along the circumferential spiral direction from one end to the other end;

[0015] The normal height change directions of the separation blocks in the same group are the same; the normal height change directions of the separation blocks in two adjacent groups are the same or opposite.

[0016] Optionally, the specifications of the separation blocks in each group are the same, and the separation blocks in each group are arranged in a staggered manner along the circumferential direction.

[0017] Optionally, the normal height of the longitudinal surface of the separation block along the axial direction gradually decreases towards the windward side.

[0018] The present invention also provides a cyclone flue gas purifier, including the separation system described in any one of the above.

[0019] The present invention provides a separation system, including at least one group of separation blocks. The separation blocks are arranged on the inner wall of the outer shell of the separation system. The separation blocks are structures protruding from the inner wall of the outer shell of the separation system. The separation blocks in each group are open curves. The separation blocks are used to block the droplets in the airflow to achieve impact interception. Since the separation is an unclosed annular structure, when the airflow hits the separation blocks, the airflow does not completely lose its axial velocity and is forced to turn into tangential velocity, but continues to move forward in a way that partially deviates from the gas flow direction, reducing the disturbance of the flow field in a larger range. The fluid that has entered the capture area is not affected. When the capture efficiency of the same-length retaining ring is basically maintained, the vortex dissipation is reduced, and at the same time, the pressure drop is smaller. By reasonably arranging the separation blocks, the present invention can obtain a higher removal efficiency under a lower original pressure drop. Description of the Drawings

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

[0021] Figure 1 Schematic diagram of the first embodiment of the separation system provided by the present invention;

[0022] Figure 2 Schematic diagram of the second embodiment of the separation system provided by the present invention;

[0023] Figure 3 Schematic diagram of the third embodiment of the separation system provided by the present invention;

[0024] Figure 4 Schematic diagram of the fourth embodiment of the separation system provided by the present invention;

[0025] Figure 5 Schematic diagram of the fifth embodiment of the separation system provided by the present invention;

[0026] Figure 6 Schematic diagram of the sixth embodiment of the separation system provided by the present invention;

[0027] Figure 7 Structural schematic diagram of a cyclone flue gas purifier.

[0028] The figure includes:

[0029] Separation block 1 and separation system housing 2. Detailed implementation manners

[0030] The core of the present invention lies in providing a separation system, which uses a non-closed separation block to reduce the blockage of the air flow.

[0031] To enable those skilled in the art to better understand the technical solution of the present invention, the separation system and the cyclone flue gas purifier of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0032] Combined with Figures 1 to 6 , each figure includes three rows of structures, which are, from top to bottom, a top view observed along the axis, a longitudinal sectional view parallel to the axis, and a longitudinal sectional view of the separation block. Figure 1 In the shown structure, a group is composed of an arc-shaped separation block 1, Figure 2 A group is composed of two arc-shaped separation blocks 1, Figure 1 And Figure 2 The separation blocks 1 are of structures with equal normal heights. Figure 3 , Figure 4 , Figure 5 , Figure 6 Are of structures with gradually changing normal heights.

[0033] The present invention provides a separation system, including at least one set of separation blocks 1. One set of separation blocks 1 includes at least one independently arranged separation block, or two or more separation blocks 1 can be provided. Each separation block 1 in one set can have the same position axially, or different positions.

[0034] The separation block 1 protrudes from the inner wall of the separation system housing 2. Both ends of the separation system housing 1 are communicated. The separation system housing is provided with a cylindrical inner cavity, and flue gas can flow from one end to the other end in the separation system housing. The flowing direction is as Figure 7 shown, flowing from the upper end to the lower end. The overall flowing direction of the flue gas is along the axial direction, that is Figure 7 the vertical direction therein.

[0035] At least one separation block 1 is provided in each set. The separation blocks 1 in each set are open curves, that is, each separation block 1 is an unclosed structure, and the separation block 1 has two non-docking ends; the separation block 1 is used to block the droplets in the airflow to achieve impact interception.

[0036] The separation system of the present invention is applied to a flue. A plurality of separation systems are installed in the inner cavity of the flue. The flue gas in the flue flows through the separation system of the present invention. The flue gas enters from the inlet end of the separation system housing 2 and exits from the outlet end. Combining Figure 7 shown, the flue gas enters the separation system housing 2 from the upper end in the direction of the arrow, flows downward along the separation system housing 2, and exits from the lower end of the separation system housing 2. Guide vanes are arranged on the inner wall near the inlet end of the separation system housing 2. When the flue gas passes through the guide vanes, a circumferential rotational motion component is generated. The flue gas rotates to generate centrifugal force, and the dust and fog particles carried in the flue gas impact on the separation block 1. The separation block 1 blocks the droplets in the airflow to achieve impact interception. The present invention realizes the interception of the dust and fog particles in the flue gas by protruding the separation block 1 in the separation system housing 2. After the flue gas is blocked by the separation block 1, it can continue to flow along the separation system housing 1. The separation block 1 can be arranged in combination with a support member to obtain a synergistic effect.

[0037] The conventional retaining ring has a good interception effect on droplets and the like on the side wall, but it greatly disturbs the flow field and has an obvious swirl elimination effect. Through research, most of the droplets are intercepted by impact within a very short time of contacting the retaining ring. This part of the fluid is forced to convert into tangential velocity in a way that completely loses its axial velocity, and the forward direction of the fluid is restricted to the cross-section of the retaining ring. However, behind the retaining ring, due to the existence of the physical wall (physical segmentation), this part of the tangential velocity is not successfully transmitted to the back side of the retaining ring. Instead, the overall swirling state of the fluid behind the retaining ring is segmented and chaotic, forming a de-swirling effect in fact. The energy loss before and after the retaining ring is very large. At a flow velocity of 15 m / s, the pressure loss of a typical circular closed retaining ring is about 15 - 40 Pa, and in most cases, it exceeds 20 Pa. Moreover, after passing through 2 - 5 fully enclosed retaining rings, the swirl will be significantly weakened or even disappear, losing the separation effect on small particles. For the separation of fine particles mainly relying on centrifugal force, this weakening has a significant impact on the separation effect in the second half of the separation area.

[0038] The separation block 1 designed in the present invention replaces the original closed annular retaining ring. While retaining the impact interception effect of droplets in the air flow, the separation block 1 does not forcefully convert into tangential velocity in a way that completely loses its axial velocity, but continues to move forward by partially deviating from the gas flow direction. It reduces the disturbance of the flow field in a larger range, and the fluid that has entered the capture area is not affected. While the capture efficiency of the retaining ring of the same length is basically maintained, the de-swirl is reduced, and at the same time, the pressure drop is smaller. By reasonably arranging the separation block 1, a higher removal efficiency can be obtained under a lower original pressure drop.

[0039] On the basis of the above scheme, the present invention provides specific indexes for the setting of the separation block 1. The total coincidence rate of the projections of all the separation blocks 1 arranged in the separation system outer casing 2 along the axial direction is 80 - 500%; that is, when observed along the axis direction, the overlapping part of several separation blocks 1 is 80 - 500%. 100% means that several separation blocks 1 exactly enclose a ring. Since the separation blocks 1 can be arranged at different positions in the axial direction, each separation block 1 is still a non-closed structure.

[0040] Along the axial direction of the separation system outer casing 2, the normal height of each separation block 1 gradually changes from the inlet to the outlet. The normal height refers to the radial dimension of the separation system outer casing 2, which is the height of the separation block 1 protruding from the inner wall of the separation system outer casing 2. The normal height of each separation block 1 itself can adopt a structure with equal height everywhere, or the normal height of each separation block 1 can gradually increase or gradually decrease from the inlet to the outlet direction.

[0041] Preferably, along the flue gas flow direction, the normal height of the separation block 1 gradually decreases from the inlet end to the outlet end, decreasing to 1 / 4 - 3 / 4 of the original height, preferably 1 / 3 - 2 / 3; a higher normal height has a more obvious blocking effect on the flue gas, and a lower normal height has a weaker blocking effect on the flue gas. During the process of the flue gas flowing from the inlet end to the outlet end, the power gradually weakens, and the normal height of the separation block 1 gradually decreases to reduce the weakening of the flue gas flow.

[0042] Specifically, each separation block 1 in the present invention is in a threaded shape, that is, the separation block 1 is arc-shaped on the circumference and has an extension in the axial direction; the number of threads of a single group of separation blocks 1 is 1 - 2 turns; the pitch is 0.5 - 2D, where D is the diameter of the inner wall surface of the separation system housing 2.

[0043] Specifically, the normal height of each separation block 1 is 2 - 8 mm; the separation block 1 itself can adopt a structure with the same height everywhere or a structure with gradually changing height.

[0044] Based on any of the above technical solutions and their combinations, the number of separation blocks 1 in the present invention is greater than three groups, and the axial spacing between adjacent two groups of separation blocks 1 gradually increases from the inlet to the outlet. Figure 3 As shown in, which shows the structure of arranging multiple groups of separation blocks 1, the axial direction is the left - right direction, and the spacing between adjacent groups of separation blocks 1 gradually increases from left to right, d1 < d2 < d3 < d4... The smaller the spacing between adjacent groups of separation blocks 1, the more obvious the blocking effect on the flue gas. In this embodiment, the spacing near the inlet end is smaller, which can more effectively block the particles in the separated flue gas, and the spacing near the outlet end is larger, which can reduce the obstruction to the flue gas.

[0045] Based on any of the above technical solutions and their combinations, the normal height of each separation block 1 gradually decreases along the circumferential spiral direction from one end to the other end; that is, the normal height of each separation block 1 itself gradually increases or decreases. Figure 3 、 Figure 4 、 Figure 5 As shown in, each of the separation blocks 1 therein has a structure with gradually changing normal height.

[0046] The normal height change directions of the separation blocks 1 in the same group are the same; Figure 3 、 Figure 4 、 Figure 5 As shown in, the normal height change directions of the separation blocks 1 in the same group are the same.

[0047] The normal height change directions of adjacent two groups of separation blocks 1 are the same or opposite. Figure 5 As shown in, which shows two groups of separation blocks 1, and the normal height change directions of the two groups of separation blocks 1 are the same, both gradually increasing in the clockwise direction. Figure 6The normal height change directions of the two sets of separation blocks 1 shown are opposite to each other.

[0048] Specifically, the specifications of the separation blocks 1 in each group in the present invention are the same, and the separation blocks 1 in each group are arranged in a staggered manner in the circumferential direction; as Figure 5 shown, the specifications of the two sets of separation blocks 1 shown are the same, and the circumferential angles of the two sets of separation blocks 1 are different, being staggered by 30 degrees from each other.

[0049] Combined with Figures 1 to 6 , in the longitudinal section structure shown, the normal height of the longitudinal surface of the separation block 1 along the axial direction gradually decreases towards the windward side, and the structure of gradually decreasing towards the windward side forms a diversion angle, which plays a role in guiding and buffering the flue gas.

[0050] The present invention also provides a cyclone flue gas purifier, including the above separation system, and this cyclone flue gas purifier can achieve the same technical effects.

[0051] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A separation system, characterized in that, It includes at least one set of separation blocks (1), and the separation blocks (1) protrude from the inner wall of the separation system housing (2). The separation blocks (1) in each set are open curves; the separation blocks (1) are used to block the droplets in the airflow to achieve impact interception; when the airflow impacts the separation blocks (1), the airflow does not forcefully change to the tangential velocity in a way that completely loses the axial velocity, but continues to move forward in a way that partially deviates from the gas flow direction, reducing the disturbance of the flow field in a larger range, reducing the swirl, and reducing the pressure drop. The separation blocks (1) are threaded; the number of turns of the thread of a single set of separation blocks (1) is 1 - 2 turns; the pitch is 0.5 - 2D, where D is the diameter of the separation system housing (2). The normal height of each separation block (1) gradually decreases from one end to the other end along the circumferential spiral direction. The normal height change directions of the separation blocks (1) in the same set are the same; the normal height change directions of adjacent two sets of separation blocks (1) are the same or opposite.

2. The separation system according to claim 1, characterized in that, The total coincidence rate of the projections of all the separation blocks (1) arranged in the separation system housing (2) along the axial direction is 80 - 500%.

3. The separation system according to claim 1, wherein Along the axial direction of the separation system housing (2), the normal height of each separation block (1) gradually changes from the inlet to the outlet.

4. The separation system according to claim 1, wherein The normal height of the separation blocks (1) is 2 - 8 mm.

5. The separation system according to any one of claims 1 to 4, characterized in that, The number of the separation blocks (1) is more than three groups, and the axial spacing between adjacent two groups of separation blocks (1) gradually increases from the inlet to the outlet.

6. The separation system according to any one of claims 1 to 4, characterized in that The specifications of each group of separation blocks (1) are the same, and each group of separation blocks (1) is arranged in a staggered manner in sequence along the circumferential direction.

7. The separation system according to any one of claims 1 to 4, characterized in that The normal height of the longitudinal surface of the separation blocks (1) along the axial direction gradually decreases towards the windward side.

8. A cyclone flue gas purifier, characterized in that, It includes the separation system according to any one of claims 1 to 7.

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