Carbonization furnace kiln smoke gas washing equipment and pyroligneous liquor circulating tank

Abstract

The utility model belongs to the field of carbonization furnace flue gas treatment equipment, and particularly relates to carbonization furnace flue gas scrubbing equipment and a pyroligneous liquor circulating tank. Comprising a scrubber tower, the scrubber tower is provided with a flue gas inlet, a flue gas outlet and a flue gas channel, and the flue gas channel is provided with a spraying pipe; and the spraying pipe is connected with a wood vinegar circulating tank. Through the connection, the pyroligneous liquor is directly used as a spraying medium, the nozzles are uniformly distributed, the contact time is prolonged, the low-concentration pyroligneous liquor is used for spraying, and the flue gas channel is cooled through the water cooling wall, so that the risk that the pyroligneous liquor component in the flue gas is increased due to the spraying of the pyroligneous liquor can be effectively controlled.

Description

Technical Field

[0001] The utility model belongs to the field of carbonization furnace smoke treatment equipment, and specifically relates to carbonization furnace smoke washing equipment and a wood vinegar liquid circulation tank. Background Art

[0002] In the production of wood biomass carbonization, flue gas treatment is a key link that requires special attention. Although conventional spray scrubbers are widely used in industrial production for flue gas cooling and dust removal, they do have some shortcomings when dealing with high-temperature and high-concentration flue gas generated during the carbonization of wood biomass.

[0003] First, the flue gas produced during the carbonization of wood biomass contains a large amount of wood vinegar. Wood vinegar is an important byproduct with a wide range of industrial applications, such as chemical raw materials, fuel additives, and agricultural fertilizers. If a conventional scrubber is used directly and water is used as the spraying medium, several problems will occur:

[0004] Decreased concentration of wood vinegar: The introduction of water will dilute the concentration of wood vinegar and reduce its economic value. For production companies, it is very important to maintain a high concentration of wood vinegar.

[0005] Mixing of water-soluble components: In addition to wood vinegar, smoke may also contain other water-soluble chemical components. Mixing these components with wood vinegar will increase the difficulty of subsequent separation and extraction, which is not conducive to obtaining high-purity wood vinegar products.

[0006] Equipment corrosion problem: Some water-soluble acidic components may aggravate the corrosion of equipment inside the scrubber and shorten the service life of the equipment.

[0007] Therefore, it is obviously inappropriate to use water alone as the spraying medium for this high-temperature flue gas containing a large amount of wood vinegar.

[0008] In addition, the flue gas temperature discharged from the wood biomass carbonization furnace is as high as 200-300℃, and the conventional scrubber has only a spraying function, which is difficult to effectively reduce such a high temperature. The direct discharge of high-temperature flue gas not only poses a safety hazard, but may also have an adverse impact on the surrounding environment. Utility Model Content

[0009] Technical problem: The problem of spray medium is solved by connecting different spray medium storage tanks through spray pipes.

[0010] Technical solution: A carbonization furnace smoke scrubbing device comprises a scrubbing tower, the scrubbing tower is provided with a smoke inlet, a smoke outlet and a smoke channel, and the smoke channel is provided with a spray pipe;

[0011] The spray pipe is connected to the wood vinegar circulation tank. Through this connection, wood vinegar is directly used as the spraying medium, the nozzles are evenly distributed, the contact time is increased, and low-concentration wood vinegar is used for spraying and the flue gas channel is cooled by the water-cooled wall, which can effectively control the risk of increasing the wood vinegar content in the flue gas due to wood vinegar spraying.

[0012] Furthermore, a water-cooled wall is provided on the scrubber. When the flue gas temperature is high, the gas-liquid distribution coefficient of wood vinegar will be biased towards the gas phase, reducing the absorption efficiency. Cooling by water-cooled wall can significantly increase the solubility of wood vinegar in the liquid phase and enhance its absorption capacity. Under high temperature conditions, the absorbed wood vinegar is easy to volatilize again into the gas phase during the subsequent treatment process. Cooling can reduce the evaporation loss of wood vinegar, which is conducive to maintaining a high concentration in the absorption liquid.

[0013] Furthermore, the flue gas channel is a single-tube or parallel multi-tube flue. Splitting a single large flue into multiple small flue tubes can greatly increase the contact area between the flue gas and the spray liquid. It is also beneficial to improve the material transfer efficiency, thereby increasing the absorption rate of the wood vinegar. Each tube is provided with a nozzle to ensure that the spray liquid is evenly distributed in the entire flue gas flow field. It avoids the local "dead corner" problem that may be caused by a single large nozzle and improves the overall flow field distribution.

[0014] Furthermore, the tower body of the scrubbing tower is a vertical tower body, the flue gas inlet is located at the top or the lower middle side wall of the vertical tower body, and the flue gas outlet is located at the lower middle side wall or the top of the vertical tower body; usually in order to provide a better spray washing effect during application, the flue gas inlet is preferably set at the lower middle part of the vertical tower body, so that the flue gas flows from bottom to top, increasing the spray time and improving the spray washing effect. In this process, due to the upward movement characteristics of high-temperature flue gas, the flue gas inlet can also be set at the top to meet the process requirements.

[0015] A liquid outlet is provided at the bottom of the tower body, which is used to collect the mixture of liquid and dust settled after spraying.

[0016] Furthermore, in order to better meet the process design requirements of the rotary carbonization kiln, the tower body of the scrubber can also be set to be horizontal, with a flue gas inlet on one side of the horizontal tower body and a flue gas outlet on the other side, and a longitudinal S-shaped flue inside the horizontal tower body. The S-shaped flue can increase the spraying time and achieve a better spraying effect, and the bottom of the tower body is designed to be inclined to collect liquid.

[0017] Furthermore, at least one section of the top of the horizontal tower body is provided with a spray pipe. The spray pipe is preferably designed to be spread over the entire top of the tower body to spray and wash the passing flue gas.

[0018] Furthermore, the smoke channel is provided with inclination angles at intervals, so that the smoke flow direction changes from an S-shape to a sawtooth shape, which can reduce the construction difficulty and ensure the spraying effect at the same time.

[0019] Furthermore, the invention comprises a scrubbing assembly, which comprises at least a plurality of scrubbing towers connected in series. The multi-stage scrubbing towers connected in series can repeatedly scrub the flue gas, thereby improving the scrubbing effect and the absorption effect of the wood vinegar.

[0020] The present application also provides a wood vinegar circulation tank, and a turbid liquid outlet and a new liquid inlet are arranged on the circulation pipe. The circulation tank is used to supply the spray medium in the spray pipe, and the turbid liquid outlet and the new liquid inlet can realize the renewal of the wood vinegar in the circulation tank to maintain its cleanliness.

[0021] It also includes a temperature control coil, which is laid on at least one surface of the wood vinegar circulation tank, and a three-way valve is provided on the inlet and outlet of the temperature control coil. The three-way valve is used to supply different temperature control media, and steam can be passed to raise the temperature of the wood vinegar to 50-70°C to prevent the wood vinegar from condensing at low temperature. When the temperature is high, cooling water is circulated from the other inlet / outlet of the three-way valve.

[0022] The beneficial effects of this application are:

[0023] 1. By using wood vinegar as the spraying medium, the problem that traditional spraying media (such as water) cannot fully absorb the wood vinegar components in the flue gas is solved. Wood vinegar itself has the ability to absorb pollutants in the flue gas, which can improve the absorption efficiency.

[0024] 2. By setting up a water-cooled wall to cool the flue gas channel, the solubility of wood vinegar in the liquid phase can be significantly improved, its absorption capacity can be enhanced, and the evaporation loss of wood vinegar can be reduced, which is conducive to maintaining a high concentration in the absorption liquid.

[0025] 3. Splitting a single large flue into multiple small flue cylinders can greatly increase the contact area between the flue gas and the spray liquid, improve the material transfer efficiency, and thus increase the absorption rate of wood vinegar.

[0026] 4. Set the flue gas inlet at the middle and lower part of the vertical or horizontal tower body to make the flue gas flow from bottom to top, increase the spraying time, and improve the effect of spray washing.

[0027] 5. The use of multi-stage series-connected scrubbing towers can repeatedly scrub the flue gas, further improving the scrubbing effect and the absorption effect of wood vinegar.

[0028] 6. The wood vinegar circulation tank is equipped with a temperature control coil, which can heat up or cool down the wood vinegar as needed to ensure that it works under the best temperature conditions and prevent low-temperature condensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1It is an overall schematic diagram of the first embodiment of the utility model;

[0030] Figure 2 It is a horizontal cross-sectional schematic diagram of the second embodiment of the utility model;

[0031] Figure 3 This is an overall schematic diagram of Embodiment 3 of the present utility model;

[0032] Figure 4 This is an overall schematic diagram of the fourth embodiment of the utility model;

[0033] Figure 5 This is a schematic diagram of the temperature control coil of the fourth embodiment of the present utility model.

[0034] In the figure: 1. vertical tower body; 2. flue gas inlet; 3. water-cooled wall; 4. water inlet; 5. water outlet; 6. spray pipe; 7. nozzle; 8. liquid outlet; 9. flue gas channel; 10. water-cooled interlayer; 11. horizontal tower body; 12. first retaining wall; 13. first-level inclined slope; 14. spray nozzle; 15. second retaining wall; 16. third retaining wall; 17. second-level inclined slope; 18. turbid liquid outlet; 19. new liquid inlet; 20. temperature control medium inlet; 21. temperature control medium outlet; 22. internal circulation pipeline; 23. circulation pump; 24. three-way valve. DETAILED DESCRIPTION

[0035] Embodiment 1:

[0036] A carbonization furnace smoke scrubbing device comprises a vertical scrubbing tower, comprising a vertical tower body 1, a smoke inlet 2 is arranged at the top of the vertical tower body 1, a smoke outlet is arranged at one side of the middle and lower part, a circulating water-cooled wall 3 is arranged on the side wall between the smoke inlet 2 and the smoke outlet, a water inlet 4 is arranged at the lower side, and a water outlet 5 is arranged at the upper side, a spray pipe 6 is arranged at the upper part of the smoke channel 9 inside the vertical tower body 1, and nozzles 7 are evenly distributed in the horizontal cross section.

[0037] The spray pipe 6 is connected to the thick liquid pump outputted by the wood vinegar on the wood vinegar circulation tank for supplying spraying power, and a liquid outlet 8 is arranged at the bottom of the vertical tower body 1 for collecting the liquid produced after spraying. The liquid outlet 8 is connected to the wood vinegar circulation tank or other collection tanks.

[0038] Embodiment 2:

[0039] The second embodiment also adopts a vertical scrubber, and its side wall is also provided with a water-cooled wall 3. Compared with the first embodiment, the difference is that the flue gas channel 9 in the vertical tower body 1 is arranged as four parallel multi-tube flue gas channels 9, and a spray nozzle 14 is arranged in each flue, and a water-cooled interlayer 10 is arranged between adjacent flues. The spray main pipe extends four branch pipes through the water-cooled interlayer 10 to provide spray medium to the nozzles 7 of the four flues. The spray arrangement is no longer shown in the attached drawings.

[0040] Embodiment three:

[0041] In the third embodiment, a horizontal scrubbing tower body is adopted, and the smoke inlet is located on the right side of the horizontal tower body 11. After entering, a first retaining wall 12 is set at the top of the interior of the horizontal tower body 11 to make the smoke move downward, and a first-level inclined slope 13 rising to the left is set at the bottom to make the smoke move upward and be sprayed by the nozzle 7 at the top.

[0042] After the smoke reaches the second retaining wall 15, dust and other solid particles adhere to the wall or fall down for collection. Those skilled in the art can collect and process the accumulated dust with reference to the prior art, and the sprayed wood vinegar is collected at the lowest side of the first-level inclined slope 13.

[0043] The flue gas passes over the second retaining wall 15 to the third retaining wall 16 and then goes down to the secondary inclined slope 17 and then to the next treatment section.

[0044] Embodiment 4:

[0045] A wood vinegar circulation tank, a circulation pipe is provided with a turbid liquid outlet 18, a new liquid inlet 19, a temperature control medium inlet 20, and a temperature control medium outlet 21. The circulation tank is used to supply the spray medium in the spray pipe 6, and the turbid liquid outlet 18 and the new liquid inlet 19 can realize the renewal of the wood vinegar in the circulation tank to maintain its cleanliness.

[0046] The circulation tank is also provided with an internal circulation pipeline 22, and a circulation pump 23 with one on and one off is provided, which is used to start the internal circulation when the spray pipe circulation is stopped or at a low speed, so that the wood vinegar in the pipe flows to prevent condensation.

[0047] The temperature control coil is also included. The temperature control coil is at least laid on one surface of the wood vinegar circulation tank. A three-way valve 24 is provided on the inlet and outlet of the temperature control coil. The three-way valve 24 is used to supply different temperature control media. Steam can be passed to raise the temperature of the wood vinegar to 50-70°C to prevent the wood vinegar from condensing at low temperature. When the temperature is high, cooling water is circulated from the other inlet / outlet of the three-way valve 24.

Claims

1. A carbonization furnace smoke scrubbing device, characterized in that: It comprises a scrubbing tower, the scrubbing tower is provided with a smoke inlet, a smoke outlet and a smoke channel (9), and the smoke channel (9) is provided with a spray pipe; The spray pipe is connected to the wood vinegar circulation tank; The tower body of the scrubbing tower is horizontal, the flue gas inlet is arranged on one side of the horizontal tower body (11), the flue gas outlet is arranged on the other side of the horizontal tower body (11), and a longitudinal S-shaped flue is arranged inside the horizontal tower body (11).

2. A carbonization furnace smoke scrubbing device as claimed in claim 1, characterized in that: A water-cooled wall (3) is provided on the scrubbing tower.

3. A carbonization furnace smoke scrubbing device as claimed in claim 1 or 2, characterized in that: The flue gas channel (9) is a single-tube type or a parallel multi-tube type flue gas channel.

4. A carbonization furnace smoke scrubbing device as claimed in claim 3, characterized in that: At least one section of the top of the horizontal tower body (11) is provided with a spray pipe (6).

5. A carbonization furnace smoke scrubbing device as claimed in claim 4, characterized in that: The smoke channel (9) is provided with inclination angles at intervals.

6. A carbonization furnace smoke scrubbing device as claimed in any one of claims 4 or 5, characterized in that: It comprises a scrubbing assembly, and the scrubbing assembly comprises at least two scrubbing towers connected in series.

7. A wood vinegar circulation tank, characterized in that: The wood vinegar circulation tank is connected to the carbonization furnace smoke scrubbing equipment according to claim 6, and a turbid liquid outlet (18) and a new liquid inlet (19) are provided on the circulation pipe.

8. A wood vinegar circulation tank as claimed in claim 7, characterized in that: It also includes a temperature control coil, which is laid on at least one surface of the wood vinegar circulation tank, and a three-way valve (24) is provided on the inlet and outlet of the temperature control coil.

Images