A crude gas dust removal and purification device and method

Abstract

The present invention discloses a raw gas dust removal and purification device and method, comprising: a shell; a tangential air inlet is provided at the bottom of the shell, and a central sprayer is provided in the shell; one or more re-swirlers are arranged axially in the shell, and the re-swirler is located above the central sprayer, and is used to re-swirl the gas; one or more top sprayers are provided in the shell, and the top sprayer is located above each re-swirler. The present invention ensures the stability and strength of the gas centrifugal field during the dust removal process and the inertial collision efficiency of droplets and dust by arranging multi-stage re-swirlers; it can achieve efficient removal of dust in the raw gas, and can adapt to the characteristics of raw gas flow fluctuation, and has a certain reliability; a top sprayer is arranged on the upper part of each re-swirler to form a synergistic effect of cyclone dust removal and washing dust removal, and enhance the dust removal effect.

Description

Technical Field

[0001] The invention relates to the technical field of raw coal gas dust removal, and in particular to a raw coal gas dust removal and purification device and method. Background Art

[0002] Underground coal gasification realizes the chemical mining of coal in a confined space underground. The raw coal gas is rich in methane, carbon monoxide, hydrogen and other profitable gases, but also contains a large amount of dust, tar, H 2 S, HCN, light hydrocarbons, ammonia, phenols, benzene, naphthalene and heavy metals and other by-products.

[0003] Dust seriously affects the safety and reliability of the system during the collection and transportation process and needs to be removed in order to eliminate the harm it brings to downstream processing and products and achieve the purification of the revenue gas.

[0004] Common dust removal and purification equipment include spray type, cyclone type, gravity settling type and Venturi type, etc. Single dust removal method often has low dust removal efficiency and cannot adapt to the characteristics of large gas flow fluctuations in underground coal gasification process.

[0005] Existing cyclone scrubbers include the following two structural forms:

[0006] 1. The dust-laden gas enters the dust collector tangentially from the bottom, and the atomizing nozzle is placed in the center of the dust collector. The gas sprays from the center of the dust collector, and leaves the dust collector after passing through the upper demister of the dust collector;

[0007] 2. The dust-laden gas enters the dust collector tangentially from the bottom, and the atomizing nozzle is placed on the top of the dust collector. The gas sprays from the top of the dust collector, and leaves the dust collector after passing through the upper demister of the dust collector.

[0008] The dust removal principle of the above cyclone scrubber is: the dust suspended in the airflow is captured by inertial collision with the spray droplets during movement, and can also be captured by moving toward the wetted wall under the centrifugal effect. Although the separation efficiency of the above cyclone scrubber is higher than that of the general spray tower or dry cyclone separator, it still has the disadvantages of low dust removal efficiency, weak reliability and poor anti-fluctuation performance. Summary of the invention

[0009] In order to solve the shortcomings of existing dust removal devices such as low dust removal efficiency, weak reliability and poor anti-fluctuation performance, the present invention provides a raw gas dust removal and purification device and method for realizing dust removal and purification of raw gas generated by underground coal gasification.

[0010] The present invention discloses a crude coal gas dust removal and purification device, comprising: a shell;

[0011] A tangential air inlet is provided at the bottom of the shell, and a central sprayer is provided inside the shell;

[0012] One or more re-swirlers are arranged axially in the shell, and the re-swirlers are located above the central sprayer and are used to re-swirl the gas;

[0013] One or more top sprayers are arranged in the shell, and the top sprayers are located above each of the re-rotators.

[0014] As a further improvement of the present invention, it also includes: a demister and an air outlet;

[0015] The demister is arranged in the shell and above the top sprayer, and the air outlet is arranged on the top of the shell.

[0016] As a further improvement of the present invention, it also includes: a downcomer and a mud collection tank;

[0017] The downcomer is arranged on the inner wall of the shell and is used to discharge the liquid and mud generated by spraying into the mud collection tank at the bottom of the shell.

[0018] The present invention also discloses a method for dust removal and purification of raw coal gas, comprising:

[0019] The raw coal gas enters the shell of the dust removal and purification device tangentially from the tangential air inlet, rotates and rises in the shell, and the dust in the raw coal gas moves toward the side wall under the action of the centrifugal force field;

[0020] During the process of raw coal gas rotating and rising, the liquid droplets generated by the central sprayer collide with the dust in the gas by inertia, capturing the dust; at the same time, the liquid droplets move to the side wall to form a liquid film, capturing the dust;

[0021] The gas is cycloned again through the re-cyclone, and the droplets generated by the top sprayer inertially collide with the dust in the gas to capture the dust; at the same time, the droplets move to the side wall to form a liquid film to capture the dust.

[0022] As a further improvement of the present invention, it also includes:

[0023] The gas after centrifugal dust removal and scrubbing dust removal passes through a demister to remove small droplets entrained in the gas;

[0024] After drying, the gas is discharged through the outlet.

[0025] As a further improvement of the present invention, it also includes:

[0026] The liquid and mud produced by the spraying are discharged into the mud collection tank at the bottom of the shell through the downcomer.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention ensures the stability and strength of the gas centrifugal field during the dust removal process by arranging a multi-stage re-rotator, and ensures the inertial collision efficiency of droplets and dust; it can not only realize the efficient removal of dust in the raw gas, but also adapt to the characteristics of raw gas flow fluctuation, and has a certain reliability;

[0029] The present invention arranges a top sprayer on the upper part of each re-spinner to form a synergistic effect of cyclone dust removal and washing dust removal, thereby enhancing the dust removal effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The present invention is a schematic structural diagram of a raw gas dust removal and purification device disclosed in an embodiment of the present invention.

[0031] In the figure:

[0032] 1. Tangential air inlet; 2. Center sprinkler; 3. Re-swirl; 4. Top sprinkler; 5. Defoamer; 6. Downcomer; 7. Air outlet; 8. Mud collection tank. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0035] like Figure 1 As shown, the present invention provides a raw gas dust removal and purification device integrating centrifugal dust removal and washing dust removal, which is used to realize dust removal and purification of raw gas generated by underground coal gasification; it includes: a tangential air inlet 1, a central sprayer 2, a re-swirl 3, a top sprayer 4, a demister 5, a downcomer 6, a gas outlet 7 and a mud collection tank 8; wherein,

[0036] A tangential air inlet 1 is provided at the bottom of the shell of the raw gas dust removal and purification device. The raw gas enters the dust removal and purification device through the tangential air inlet 1. The gas enters tangentially and rotates and rises in the shell. During the rotation and rising process, the dust in the raw gas moves toward the side wall under the action of the centrifugal field.

[0037] A central sprayer 2 is provided in the shell of the raw gas dust removal and purification device. The liquid outlet end of the central sprayer 2 is preferably arranged on the axis of the shell, and the outer end of the shell of the central sprayer 2 is connected to the water inlet pipe, and the inner end of the shell produces droplets; the droplets collide with the dust in the raw gas by inertia to capture the dust; at the same time, the droplets move to the side wall of the shell to form a liquid film, and the liquid film can capture the dust that moves to the side wall under the action of centrifugation.

[0038] One or more re-swirlers 3 are arranged axially in the shell of the raw gas dust removal and purification device. The re-swirlers 3 are located above the central sprayer 2. They are used to cyclone the raw gas again to make it rotate and rise, so as to ensure the stability and strength of the gas centrifugal field during the dust removal process. The number of re-swirlers 3 can be selected according to the actual working conditions and the requirements of dust removal efficiency.

[0039] One or more top sprayers 4 are provided in the shell of the raw gas dust removal and purification device, and the top sprayers 4 are located above each re-rotator 3; the top sprayers 4 are preferably arranged on the axis of the shell, and the outer end of the shell of the top sprayers 4 is connected to the water inlet pipe, and the inner end of the shell produces droplets; the droplets collide with the dust in the raw gas by inertia to capture the dust; at the same time, the droplets move to the side wall of the shell to form a liquid film, and the liquid film can capture the dust that moves to the side wall under the action of centrifugation.

[0040] A demister 5 is provided in the shell of the raw gas dust removal and purification device. The demister 5 is located above the top sprayer 4 and is used to remove small droplets entrained in the gas due to spraying.

[0041] A gas outlet 7 is provided on the top of the shell of the raw gas dust removal and purification device, and the gas after dust removal and purification by the central sprayer 2, the re-swirler 3, the top sprayer 4 and drying by the demister 5 is discharged through the gas outlet 7.

[0042] One or more downcomers 6 are provided on the side wall of the shell of the raw gas dust removal and purification device for discharging the liquid and mud produced by spraying to the mud collection tank 8 .

[0043] A mud collecting tank 8 is provided at the bottom of the shell of the raw gas dust removal and purification device for temporarily removing and washing muddy sewage formed during the dust removal process.

[0044] Based on the above-mentioned raw gas dust removal and purification device, the present invention provides a raw gas dust removal and purification method, comprising:

[0045] Step 1, the raw coal gas enters the shell of the dust removal and purification device tangentially from the tangential air inlet 1, rotates and rises in the shell, and the dust in the raw coal gas moves toward the side wall under the action of the centrifugal force field;

[0046] Step 2: During the process of the raw gas rotating and rising, the droplets generated by the central sprayer 2 collide with the dust in the raw gas by inertia, capturing the dust; at the same time, the droplets move to the side wall to form a liquid film, capturing the dust centrifugally moving to the side wall;

[0047] Step 3: The gas is cycloned again through the re-cyclone 3, and the droplets generated by the top sprayer 4 collide with the dust in the gas by inertia to capture the dust; at the same time, the droplets move to the side wall to form a liquid film to capture the dust;

[0048] Step 4: The gas after centrifugal dust removal and washing dust removal passes through the demister 5 to remove small droplets entrained in the gas, and the gas is discharged through the outlet 7 after drying;

[0049] Step 5: The liquid and slurry generated by the spraying are discharged into the slurry collection tank 8 at the bottom of the shell through the downcomer 6.

[0050] The advantages of the present invention are:

[0051] The present invention ensures the stability and strength of the gas centrifugal field during the dust removal process by arranging a multi-stage re-rotator, and ensures the inertial collision efficiency of droplets and dust; it can not only realize the efficient removal of dust in the raw gas, but also adapt to the characteristics of raw gas flow fluctuation, and has a certain reliability;

[0052] The present invention arranges a top sprayer on the upper part of each re-spinner to form a synergistic effect of cyclone dust removal and washing dust removal, thereby enhancing the dust removal effect.

[0053] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A raw gas dust removal and purification device, characterized in that: include: Shell, downcomer and mud collection tank; A tangential air inlet is provided at the bottom of the shell, and the raw coal gas enters the shell tangentially through the tangential air inlet and rotates and rises in the shell. During the rotating and rising process, dust in the raw coal gas moves toward the side wall under the action of the centrifugal force field; A central sprayer is arranged in the shell, and the droplets generated by the central sprayer collide with the dust in the raw gas by inertia to capture the dust; at the same time, the droplets generated by the central sprayer move to the side wall to form a liquid film to capture the dust centrifugally moving to the side wall; One or more re-swirlers are arranged axially in the shell, and the re-swirlers are located above the central sprayer and are used to re-swirl the gas; One or more top sprayers are disposed in the housing, and the top sprayers are located above each of the re-rotators; The downcomer is arranged on the inner wall of the shell and is used to discharge the liquid and mud generated by spraying into the mud collection tank at the bottom of the shell.

2. The raw coal gas dust removal and purification device according to claim 1, characterized in that: Also includes: Defoamer and air outlet; The demister is arranged in the shell and above the top sprayer, and the air outlet is arranged on the top of the shell.

3. A dust removal and purification method for a raw gas dust removal and purification device according to any one of claims 1 to 2, characterized in that: include: The raw coal gas enters the shell of the dust removal and purification device tangentially from the tangential air inlet, rotates and rises in the shell, and the dust in the raw coal gas moves toward the side wall under the action of the centrifugal force field; During the process of raw coal gas rotating and rising, the liquid droplets generated by the central sprayer collide with the dust in the gas by inertia, capturing the dust; at the same time, the liquid droplets move to the side wall to form a liquid film, capturing the dust; The gas is cycloned again through the re-cyclone, and the droplets generated by the top sprayer inertially collide with the dust in the gas to capture the dust; at the same time, the droplets move to the side wall to form a liquid film to capture the dust.

4. The dust removal and purification method according to claim 3, characterized in that: Also includes: The gas after centrifugal dust removal and scrubbing dust removal passes through a demister to remove small droplets entrained in the gas; After drying, the gas is discharged through the outlet.

5. The dust removal and purification method according to claim 3, characterized in that: Also includes: The liquid and mud produced by the spraying are discharged into the mud collection tank at the bottom of the shell through the downcomer.

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