Organic waste gas incineration tail gas treatment device

Abstract

The invention relates to the technical field of tail gas treatment, in particular to an organic waste gas incineration tail gas treatment device which comprises a reaction container and a product container, a Laval pipe is arranged in a reaction cavity, and a suction inlet used for sucking a reaction solution is formed in a contraction section of the Laval pipe; a converging filler is mounted at the part, directly facing the butting port, of the product cavity of the product container, and after the airflow collides with the converging filler and is decelerated, the small liquid drops are gathered in the converging filler to form large liquid drops and then drop down; according to the device, airflow is subjected to first-stage acceleration through the Laval pipe, airflow is subjected to second-stage acceleration through the airflow channel, and therefore the gas-liquid two-phase velocity difference is increased, broken fog drops can be further atomized under the strong action of gas power to form water mist, the water mist can promote nitrogen dioxide to be dissolved in the water mist, nitrate is formed in the water mist, and the nitrogen dioxide can be dissolved in the water mist to form nitrogen dioxide. Nitrate in the water mist and carbon dioxide in the combustion tail gas can generate urea, so that nitric oxide in the tail gas is removed, and useful fertilizer is generated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tail gas treatment, in particular to an organic waste gas incineration tail gas treatment device. BACKGROUND

[0002] The waste gas incinerator is used for increasing the temperature of the combustible harmful gas to the reaction temperature by using the heat generated by the auxiliary fuel combustion, so that the oxidation decomposition is generated. It is suitable for the harmful gas purification of the spraying, drying and petrochemical industry, medicine and other industries. The method shows its advantages for the gas purification of the water-soluble or viscous substances and high molecular substances in the organic waste gas. The method meets the requirements of environmental protection and labor protection, and increases the heat exchange equipment to achieve the purpose of waste heat reuse and energy saving.

[0003] However, the carbon dioxide generated after the organic waste gas is burned is often ignored, and the organic waste gas is directly converted into carbon emission, which aggravates the greenhouse effect and climate change problem. In addition, during the combustion process, the temperature in the incinerator is relatively high, generally above 1000 DEG C. At this time, a large amount of thermal nitrogen oxides are generated in the high temperature zone of the flame, resulting in that the nitrogen oxides in the final emission flue gas are over-standard. The nitrogen oxides are mainly nitrogen monoxide and nitrogen dioxide, and nitrogen dioxide is mainly used. Nitrogen oxides have different degrees of toxicity, which directly harm the respiratory system of the human body and the ecological environment. SUMMARY

[0004] The technical problem to be solved by the present application is that in order to overcome the problem that the organic waste gas is directly converted into carbon emission after being burned in the prior art, and a large amount of thermal nitrogen oxides are generated during the combustion process, resulting in that the nitrogen oxides in the final emission flue gas are over-standard, the present application provides an organic waste gas incineration tail gas treatment device.

[0005] To solve the above technical problems, the present application adopts the following technical scheme: an organic waste gas incineration tail gas treatment device, comprising: A reaction container, which is internally formed with a reaction cavity and has a tail gas inlet and a mixing outlet communicated with the reaction cavity, a Laval tube for accelerating the tail gas entering from the tail gas inlet is arranged in the reaction cavity, a suction inlet for sucking the reaction solution to react with the tail gas is arranged on the contraction section of the Laval tube, the reaction solution is a mixed powder suspension of calcium carbonate and calcium phosphate, the suspension entering the contraction section from the suction inlet forms water mist and contacts with the nitrogen oxides in the tail gas, the nitrogen dioxide in the water mist is dissolved to form nitrate, and the carbon dioxide in the tail gas reacts with the nitrate to generate urea. And a product container, which is internally formed with a product cavity, and has a gas outlet, a liquid outlet and a butt joint for connecting the mixing outlet and the product cavity, and a converging filler is installed at the part of the product cavity opposite to the butt joint, and the gas flow collides with the converging filler to slow down, and small liquid drops gather to form large liquid drops in the converging filler and then drop down.

[0006] Further, the reaction cavity is provided with a heat exchange pipe for cooling the gas flow at the part downstream of the Laval pipe along the gas flow direction.

[0007] Further, one end of the heat exchange pipe is a cooling liquid inlet, and the other end is a cooling liquid outlet, and the heat exchange pipe is provided with a gas flow channel along the gas flow direction, and the diameters of the two ends of the gas flow channel are larger than the diameter of the middle part to form a Laval structure.

[0008] Further, the product container is provided with an air inlet for connecting with the product cavity at the part below the converging filler, and air enters the product cavity from the air inlet to oxidize the residual nitrogen monoxide into nitrogen dioxide.

[0009] Further, the reaction container is a cylinder structure extending in the transverse direction, and the product container is a cylinder structure extending in the longitudinal direction, and the two are perpendicular to each other.

[0010] Further, the product cavity is provided with a vibration element for vibrating the converging filler.

[0011] Further, the product cavity is provided with a partition plate, and the partition plate and the cavity wall of the product cavity form a sandwich layer for installing the vibration element, and the vibration element and the converging filler are respectively located on the two sides of the partition plate and both are attached to the partition plate.

[0012] Further, the middle part of the partition plate is protruded to form a positioning top convex, and the converging filler is recessed to form a positioning cavity for embedding the positioning top convex to fix itself.

[0013] Further, the product cavity is provided with a defoaming filler at the part below the gas outlet.

[0014] Further, the weight ratio of calcium carbonate and calcium phosphate in the reaction container is 1:3-4, and the solid-liquid mass ratio is 1:1000-2000.

[0015] The beneficial effects of the present application are: (1) The present application uses the Laval pipe to accelerate the gas flow in the first stage, and uses the gas flow channel to accelerate the gas flow in the second stage, so as to increase the velocity difference between the gas and liquid phases, and the broken mist drops will be further atomized under the strong action of the gas power to form fine water mist. (2) The fine water mist in the application can promote the dissolution of nitrogen dioxide in the water mist, and form nitrate in the water mist, and the nitrate in the water mist can further generate urea with carbon dioxide in the combustion tail gas on the water droplet interface, so that the nitrogen oxides in the tail gas are removed, and useful fertilizer is generated, and the synthesis speed of carbon dioxide and nitrate attached to the surface of the water mist can be further improved; (3) The application can not only effectively remove carbon dioxide and nitrogen oxides in the incineration tail gas, but also remove fine particles in the exhaust gas, and has good purification effect.

[0016] (4) The application can improve the yield of urea and the removal rate of nitrogen oxides by using the catalytic effect of the filler. BRIEF DESCRIPTION OF DRAWINGS

[0017] The application will be further described below in combination with the drawings and examples.

[0018] Figure 1 The figure is a structural schematic diagram of the application; Figure 2 is Figure 1 A partial enlarged view of part A in the figure; In the figure: 1, reaction container; 101, reaction cavity; 102, tail gas inlet; 103, mixing outlet; 2, product container; 201, product cavity; 202, gas outlet; 203, liquid outlet; 204, docking port; 205, air inlet; 206, partition; 2061, positioning top protrusion; 2062, upper inclined portion; 2063, lower inclined portion; 207, interlayer.

[0019] 3, Laval tube; 301, converging section; 302, suction inlet; 4, liquid inlet pipe; 5, heat exchange pipe; 501, cooling liquid inlet; 502, cooling liquid outlet; 503, air flow channel; 6, vibration element; 7, converging filler; 701, positioning cavity; 8, defoaming filler; 9, liquid storage tank. DETAILED DESCRIPTION

[0020] The application will be further described below in combination with the drawings and examples. These drawings are all simplified schematic diagrams, and only schematically show the basic structure of the application, so that only the structures related to the application are shown, and the directions and references such as up, down, left, right, etc. can only be used to help the description of the features in the drawings. Therefore, the following detailed description is not in the limiting sense, and the scope of the claimed subject matter is only defined by the appended claims and their equivalents. EXAMPLE

[0021] As shown in Figure 1 and Figure 2 The present application is a kind of organic waste incineration tail gas treatment device, comprising reaction vessel 1 and product container 2: The reaction vessel 1 is formed with reaction cavity 101 inside and has tail gas inlet 102 and mixing outlet 103 communicating with the reaction cavity 101, the reaction cavity 101 is configured with a Laval tube 3 inside for accelerating the tail gas entering from the tail gas inlet 102, the convergent section 301 of the Laval tube 3 is provided with a suction inlet 302 for sucking reaction solution to react with the tail gas, the reaction vessel 1 is provided with a liquid storage tank 9 below for containing the reaction solution, a liquid inlet pipe 4 is connected between the liquid storage tank 9 and the Laval tube 3, the liquid inlet pipe 4 passes through the reaction vessel 1 and extends into the Laval tube 3, the tail gas flows into the reaction cavity 101 from the tail gas inlet 102, the flow rate increases when passing through the convergent section 301 of the Laval tube 3, the gas pressure decreases to have a pressure difference with the atmospheric pressure, and the reaction solution is sucked into the Laval tube 3 under the action of the pressure difference; The reaction solution is a mixed powder suspension of calcium carbonate and calcium phosphate, the suspension entering the convergent section 301 from the suction inlet 302 increases the nozzle gas flow velocity by Laval effect, thereby increasing the gas-liquid two-phase velocity difference, the broken droplets are further atomized under the strong action of gas power to form fine water mist, the fine water mist can promote the dissolution of nitrogen dioxide in the water mist, and the nitrogen dioxide and water react to generate nitric acid and release nitric oxide, the nitric acid reacts with calcium carbonate and calcium phosphate in the suspension to generate nitrate in small droplets, and the nitrate reacts with carbon dioxide in the gas flow to generate urea.

[0022] The product container 2 is formed with a product cavity 201 inside, and has a gas outlet 202, a liquid outlet 203 and a butt joint 204 for connecting the mixing outlet 103 and the product cavity 201, and the product cavity 201 is installed with a converging filler 7 opposite to the butt joint 204, the gas flow collides with the converging filler 7 to slow down, and the small droplets form large droplets in the converging filler 7 and then drop down.

[0023] The present application utilizes the Laval tube to accelerate the gas flow, thereby increasing the gas-liquid two-phase velocity difference, the broken droplets are further atomized under the strong action of gas power to form fine water mist; the fine water mist can promote the dissolution of nitrogen dioxide in the water mist, and form nitrate in the water mist, the nitrate in the water mist can further react with carbon dioxide in the combustion tail gas to generate urea on the interface of water droplets, so that the nitrogen oxides in the tail gas are removed, and useful fertilizer is generated, and the synthesis speed of carbon dioxide and nitrate attached to the surface of the water mist can be further improved, thereby effectively removing carbon dioxide and nitrogen oxides in the incineration tail gas.

[0024] In some examples, the reaction chamber 101 is provided with a heat exchange pipe 5 downstream of the Laval tube 3 along the direction of the gas flow, which is used to cool the gas flow. After the cooling effect of the heat exchange pipe 5, the reaction speed of the remaining oxygen in the nitrogen monoxide and the tail gas is accelerated, and nitrogen dioxide is generated again, which is dissolved into the small droplets to generate nitrate. The nitrate in the small droplets continues to contact with the carbon dioxide to generate urea.

[0025] In some examples, one end of the heat exchange pipe 5 is a cooling liquid inlet 501, and the other end is a cooling liquid outlet 502. In order to prolong the contact time of the cooling liquid and the gas flow, the cooling liquid inlet 501 is located at the lower end of the heat exchange pipe 5, and the cooling liquid outlet 502 is located at the upper end of the heat exchange pipe 5. The heat exchange pipe 5 is provided with a gas flow channel 503 along the direction of the gas flow. The diameter of the gas flow channel 503 at both ends is larger than the diameter of the middle part to form a Laval structure. After the gas flow enters the reaction chamber 101 from the tail gas inlet 102, it is first accelerated by the Laval tube 3, and then is secondly accelerated by the gas flow channel 503, so that the speed is further increased. With the high-speed movement of the gas flow, the gas flow impacts the surface of the converging packing 7, and a very high impact force is formed between the gas bubbles and the surface of the packing, which forms a local high temperature, so that the production rate of urea is increased, and the residual nitrogen oxides are completely converted into urea.

[0026] Preferably, the gas flow channel 503 has a plurality of longitudinal and side-by-side distribution, so as to increase the contact area of the cooling liquid and the gas flow, and improve the heat exchange effect.

[0027] In some examples, the product container 2 is provided with an air inlet 205 at a position below the converging packing 7, which is used to communicate with the product chamber 201. The air enters the product chamber 201 from the air inlet 205 and moves upward, and the oxygen therein oxidizes the residual nitrogen monoxide into nitrogen dioxide for subsequent dissolution.

[0028] In some examples, the reaction container 1 is a horizontally extending cylinder structure, and the product container 2 is a vertically extending cylinder structure, and the two are perpendicular to each other.

[0029] In some examples, the product chamber 201 is provided with a vibration element 6 for vibrating the converging packing 7. During the vibration of the converging packing 7, the liquid droplets in the converging packing 7 can smoothly drop. The vibration element 6 can be an ultrasonic transducer, and the number thereof can be one, two or three, but is not limited thereto.

[0030] In some examples, the product chamber 201 is provided with a partition 206, which, together with the chamber wall of the product chamber 201, forms a sandwich layer 207 for mounting the vibrating element 6. The vibrating element 6 and the converging filler 7 are respectively located on the two sides of the partition 206 and are attached to the partition 206. When the vibrating element 6 on one side of the partition 206 is turned on, power can be completely transmitted to the converging filler 7 through the partition 206 to make it vibrate.

[0031] In some examples, the partition 206 is located at least on one side of the converging filler 7 and away from the reaction container 1 to avoid interference with the movement of the gas flow. The middle part of the partition 206 is protruded to form a positioning top protrusion 2061. The converging filler 7 is recessed to form a positioning cavity 701 for embedding the positioning top protrusion 2061 to fix itself. After the positioning top protrusion 2061 is embedded in the positioning cavity 701, the converging filler 7 can be longitudinally positioned, further improving the fixing effect of the converging filler 7.

[0032] Preferably, the partition 206 includes an upper inclined part 2062 inclined towards the reaction container 1 from top to bottom and a lower inclined part 2063 inclined away from the reaction container 1 from top to bottom. The inclined upper inclined part 2062 and the lower inclined part 2063 are beneficial to the sliding of liquid droplets. The intersection of the upper inclined part 2062 and the lower inclined part 2063 forms the positioning top protrusion 2061.

[0033] In some examples, the product chamber 201 is provided with a demisting filler 8 below the gas outlet 202. The demisting filler 8 is a fluff made of stainless steel material compacted and calcined at 800℃, and then naturally cooled to obtain a stack. Nitrous oxide formed by oxidation of the demisting filler 8 with air can be further dissolved into water droplets when moving upward with the gas flow.

[0034] In some examples, the weight ratio of calcium carbonate to calcium phosphate is 1:3-4, the solid-liquid mass ratio is 1:1000-2000, and the particle diameter of the suspension is 100-300 mesh.

[0035] Working principle: When in operation, the incinerator tail gas flows into the reaction cavity 101 from the tail gas inlet 102, and the flow rate increases and the air pressure decreases as the tail gas passes through the converging section 301 of the Laval tube 3, so that the reaction solution below is sucked from the liquid inlet pipe 4 into the tail gas to form water mist. The water mist and the nitrogen oxides in the tail gas contact each other, and the nitrogen dioxide and water in the water mist react to generate nitric acid and release nitric oxide. The nitric acid reacts with calcium carbonate and calcium phosphate in the suspension to generate nitrate in the small mist droplets. The nitrate and the carbon dioxide in the gas flow contact and react with each other at the interface of the water droplets to generate urea. The nitric oxide and the residual oxygen in the tail gas react at a faster speed due to the cooling effect of the heat exchange pipe 5 to generate more nitrogen dioxide, which is dissolved into the small droplets to generate more nitrate. The nitrate in the small droplets continues to contact with the carbon dioxide to generate urea. After the gas flow passes through the gas flow channel 503 of the heat exchange pipe 5, the speed of the gas flow is further increased. With the high-speed movement of the gas flow, the gas flow collides with the surface of the converging packing 7 to form a high impact force between the gas bubbles and the surface of the converging packing 7, so that a local high temperature is formed to increase the generation rate of urea and completely convert the residual nitrogen oxides into urea. With the collision between the small droplets and the surface of the converging packing 7, the small droplets slow down and gather in the converging packing 7 to form large droplets. The ultrasonic vibrator vibrates the converging packing 7 to make the droplets on the surface of the packing smoothly drip down. The air introduced from the air inlet 205 provides a part of oxygen to oxidize the possible unoxidized nitric oxide into nitrogen dioxide. At the same time, the gas flow moves upward and contacts with the defoaming packing 8 to continue to dissolve into the water droplets. The water droplets on the surface of the converging packing 7 contain urea, which drips down with the water droplets. When the amount of the urea reaches a certain amount, the urea is discharged from the liquid outlet 203, and the gas is discharged from the gas outlet 202.

[0036] The above description is only an ideal embodiment of the present application, and the related personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the content of the specification, and must be determined according to the scope of the claims.

Claims

1. An organic waste gas incineration tail gas treatment device, characterized in that: include: The reaction vessel (1) has a reaction chamber (101) inside and has an exhaust gas inlet (102) and a mixing outlet (103) connected to the reaction chamber (101). The reaction chamber (101) is equipped with a Laval tube (3) for accelerating the exhaust gas entering from the exhaust gas inlet (102). The constriction section (301) of the Laval tube (3) has an intake port (302) for drawing in a reaction solution to react with the exhaust gas. The reaction solution is a mixed powder suspension of calcium carbonate and calcium phosphate. The suspension entering the constriction section (301) from the intake port (302) forms a water mist and comes into contact with nitrogen oxides in the exhaust gas. The nitrogen dioxide in the water mist dissolves to form nitrates and reacts with carbon dioxide in the exhaust gas to generate urea. The product container (2) has a product cavity (201) inside, and has an air outlet (202), a liquid outlet (203) communicating with the product cavity (201) and a connection port (204) for communicating with the mixing outlet (103) and the product cavity (201). A converging packing (7) is installed in the part of the product cavity (201) facing the connection port (204). After the airflow collides and decelerates with the converging packing (7), the small droplets merge into large droplets in the converging packing (7) and then drip down.

2. The organic waste gas incineration tail gas treatment device according to claim 1, characterized in that: The reaction chamber (101) is provided with a heat exchange tube (5) for cooling the airflow at a position downstream of the Laval tube (3) along the airflow direction.

3. The organic waste gas incineration tail gas treatment device according to claim 2, characterized in that: The heat exchange tube (5) has a coolant inlet (501) at one end and a coolant outlet (502) at the other end. The heat exchange tube (5) has an airflow channel (503) along the airflow direction. The diameters at both ends of the airflow channel (503) are larger than the diameter at the middle to form a Laval structure.

4. The organic waste gas incineration tail gas treatment device according to claim 1, characterized in that: The product container (2) is provided with an air inlet (205) for communicating with the product chamber (201) at the part below the collecting packing (7). Air enters the product chamber (201) from the air inlet (205) to oxidize the remaining nitric oxide into nitrogen dioxide.

5. The organic waste gas incineration tail gas treatment device according to claim 1, characterized in that: The reaction vessel (1) is a cylindrical structure extending laterally, and the product vessel (2) is a cylindrical structure extending longitudinally, with the two being perpendicular to each other.

6. The organic waste gas incineration tail gas treatment device according to claim 1, characterized in that: The product chamber (201) is equipped with a vibrating element (6) for vibrating the converging packing (7).

7. The organic waste gas incineration tail gas treatment device according to claim 6, characterized in that: The product cavity (201) is provided with a partition (206), and the partition (206) and the cavity wall of the product cavity (201) form a sandwich (207) for the installation of the vibration element (6). The vibration element (6) and the converging filler (7) are located on both sides of the partition (206) and both are in contact with the partition (206).

8. The organic waste gas incineration tail gas treatment device according to claim 7, characterized in that: The partition (206) has a protruding center to form a positioning top protrusion (2061), and the converging filler (7) has a recessed center to form a positioning cavity (701) for the positioning top protrusion (2061) to be embedded in in order to fix itself.

9. The organic waste gas incineration tail gas treatment device according to claim 1, characterized in that: The product chamber (201) is equipped with a defoaming packing (8) located below the air outlet (202).

10. The organic waste gas incineration tail gas treatment device according to claim 1, characterized in that: The weight ratio of calcium carbonate to calcium phosphate in the reaction solution is 1:3-4, and the solid-liquid mass ratio is 1:1000-2000.

Images