A flue gas desulfurization system for biomass combustion

Abstract

The invention relates to the technical field of flue gas desulfurization, and in particular to a flue gas desulfurization system for biomass combustion, comprising a primary desulfurization tower, the top of which is connected to a secondary desulfurization pool through a conveying pipe; a vibrating cyclone is installed on the top of the primary desulfurization tower, and a flue gas cyclone chamber, a flue gas atomization chamber and a desulfurization chamber are sequentially arranged inside the primary desulfurization tower from bottom to top; a permeable plate is arranged between the desulfurization chamber and the flue gas atomization chamber; the flue gas atomization chamber is used to atomize and moisten the flue gas; the vibrating cyclone can provide fine particles of carbide slag to the desulfurization chamber; a slag delivery mechanism is installed in the desulfurization chamber, and the slag delivery mechanism can evenly scatter the carbide slag on the permeable plate; a plurality of through holes are arranged on the permeable plate, and the through holes only allow the atomized and moistened flue gas to pass through; the secondary desulfurization pool can use seawater to desulfurize the flue gas and discharge qualified flue gas and seawater. The carbide slag is used as the main desulfurizer to achieve waste treatment with waste, and seawater is used as the secondary desulfurizer, which is environmentally friendly and has no secondary pollution.

Description

Technical Field

[0001] The invention relates to the technical field of flue gas desulfurization, and in particular to a flue gas desulfurization system for biomass combustion. Background Art

[0002] During the combustion of biomass, a large amount of flue gas will be emitted, among which there are many kinds of non-polluting substances with complex components, mainly including SO2, inhalable particulate matter and NOx. Once these non-polluting substances spread into the air, they will not only cause serious air pollution, but also threaten the surrounding ecological environment and affect the health of surrounding residents. In order to reduce the impact of flue gas emissions on the atmospheric environment, power plants usually treat flue gas to meet the requirements of environmentally friendly production. Among them, SO2 and inhalable particulate matter will cause acid rain, haze and other adverse environmental impacts, and are considered to be the key objects to be removed.

[0003] At present, the existing flue gas desulfurization technologies include wet desulfurization and dry desulfurization. Among them, wet desulfurization technology is the most widely used. Wet flue gas desulfurization is the process adopted by about 85% of large thermal power plants in the world today, and the flue gas desulfurization absorption system and method are its key core equipment, which have been widely used in engineering. The principle of the wet flue gas desulfurization absorption system and method is to use limestone alkaline slurry to spray from top to bottom, and the flue gas flows from bottom to top. The limestone slurry drops absorb SO2 in the flue gas during the falling overstroke process, so as to achieve the purpose of removing SO2 from the flue gas, but the cost is high, the desulfurization efficiency is low, and it will cause secondary pollution. At the same time, the prior art also uses carbide slag desulfurization method, which adopts the form of spraying carbide slag slurry. Ca (OH) 2 will be generated during the desulfurization process, and Ca (OH) 2 is slightly soluble in water and can easily cause carbide slag slurry to block the equipment pipeline. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects and shortcomings in the prior art. To this end, the present invention provides a biomass combustion flue gas desulfurization system, which can avoid secondary pollution to the environment and improve the desulfurization efficiency of the flue gas.

[0005] In order to achieve the above-mentioned object, the present invention provides a flue gas desulfurization system for biomass combustion, which comprises: a primary desulfurization tower, the top of which is connected to a secondary desulfurization tank through a conveying pipe; a vibrating cyclone is installed on the top of the primary desulfurization tower, and a flue gas cyclone chamber, a flue gas atomization chamber and a desulfurization chamber are sequentially arranged inside the primary desulfurization tower from bottom to top; a permeable plate is arranged between the desulfurization chamber and the flue gas atomization chamber;

[0006] A counter-rotating unit is arranged in the flue gas cyclone chamber, and the counter-rotating unit is configured to be able to vertically transport the flue gas upward into the flue gas atomization chamber along the axial direction of the primary desulfurization tower;

[0007] An atomizing mechanism is provided on the outer circumference of the smoke atomizing chamber, and the atomizing mechanism is configured to provide mist water to the smoke atomizing chamber and atomize and moisten the smoke;

[0008] The vibrating cyclone is configured to provide fine-grained carbide slag to the desulfurization chamber;

[0009] A slag conveying mechanism is installed in the desulfurization chamber, and the slag conveying mechanism is configured to evenly scatter the carbide slag on the air permeable plate; a plurality of through holes are provided on the air permeable plate, and the through holes are configured to only allow atomized and moistened flue gas to pass through;

[0010] The secondary desulfurization tank is configured to utilize seawater to desulfurize the flue gas and discharge qualified flue gas and seawater.

[0011] Furthermore, the counter-rotating unit includes an air supply shunt pipe and two sets of air supply mechanisms, the air supply mechanism includes a fairing and an impeller driven by a motor A, the motor A is horizontally fixed in the fairing, and the fairing is connected to the air supply shunt pipe; the two impellers are arranged opposite to each other.

[0012] Furthermore, the atomization mechanism includes an annular shell, a plurality of fans are installed on the shell, a clean water trough is arranged at the bottom of the shell, a wet film material is arranged opposite to the fan, and the clean water trough injects water into the wet film material through a water pump; a plurality of atomization holes are opened on the outer wall of the smoke atomization chamber, the atomization holes correspond to the positions of the wet film material, and the wet film material is fixed on the outer wall of the smoke atomization chamber.

[0013] Furthermore, the slag conveying mechanism includes a collecting trough, the upper end of which is connected to the vibrating cyclone, a discharge hopper is provided at the lower end of the collecting trough, a rotatable shaft is provided in the middle of the collecting trough, a plurality of equalizing plates are fixed to the lower end of the shaft, and a radial dimension of the equalizing plate is the inner diameter of the primary desulfurization tower; a sieve plate is sealed below the equalizing plate, and the sieve plate is configured to be able to slide on the upper end surface of the sieve plate; a slag discharge port is provided on one side of the sieve plate.

[0014] Furthermore, a driven pulley is arranged on the top of the rotating shaft, a motor B is arranged on the outer wall of the desulfurization chamber, a driving pulley is arranged on the motor B, and the driving pulley drives the driven pulley to rotate through a belt.

[0015] Furthermore, vibration motors are installed on both sides of the collecting tank.

[0016] Furthermore, the secondary desulfurization tank is divided into a seawater absorption tank and an aeration tank which are connected from top to bottom, and the delivery pipe is connected to the seawater absorption tank.

[0017] Furthermore, a cone-shaped conveying cover is provided at the air outlet end of the conveying pipe, and the conveying cover is configured to extend into the seawater in the seawater absorption tank.

[0018] Furthermore, a smoke exhaust port is provided at the top of the seawater absorption tank, a water inlet is provided at one side of the seawater absorption tank, a pH online monitor is installed on the side wall of the seawater absorption tank, and a drain port A is provided at the lower end of the seawater absorption tank.

[0019] Furthermore, an air inlet pipe is provided at the bottom of the aeration tank, a plurality of aerators are provided on the air inlet pipe, and a drain outlet B is provided on one side of the aeration tank.

[0020] Compared with the prior art, the invention has the following beneficial effects: using carbide slag as the main desulfurizing agent, achieving waste treatment with waste, using seawater as the secondary desulfurizing agent, being environmentally friendly and free of secondary pollution. At the same time, it improves the SO2 removal efficiency and reduces the operating cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a simplified schematic diagram of the present invention.

[0022] Figure 2 for Figure 1 Schematic cross-section diagram of .

[0023] Figure 3 It is a partial top view of the slag feeding mechanism in the present invention.

[0024] Among them: 1. Primary desulfurization tower; 2. Secondary desulfurization tank; 3. Vibrating cyclone; 4. Atomization mechanism; 5. Delivery pipe; 11. Flue gas cyclone chamber; 12. Flue gas atomization chamber; 13. Desulfurization chamber; 21. Seawater absorption tank; 22. Aeration tank; 31. Large particle cyclone layer; 32. Fine particle cyclone layer; 33. Calcium carbide slag inlet; 34. Large particle outlet; 35. Fine particle outlet; 41. Wet film material; 42. Water pump; 43. Fan; 44. Clean water tank; 45. Casing; 51. Delivery cover; 111. Fairing; 112. Motor A; 113. Impeller; 114. Gas transmission and diversion Tube; 121, atomizing hole; 131, air permeable plate; 132, slag discharge port; 133, equalizing plate; 134, sieve plate; 135, rotating shaft; 136, collecting tank; 137, vibration motor; 211, pH online monitor; 212, water inlet; 213, smoke outlet; 214, drain outlet A; 221, aerator; 222, air inlet pipe; 223, drain outlet B; 135-1, driven pulley; 135-2, motor B; 135-3, driving pulley. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0027] Example

[0028] See also Figures 1 to 3 The present invention provides a flue gas desulfurization system for biomass combustion, comprising a primary desulfurization tower 1, the top of which is connected to a secondary desulfurization tank 2 through a delivery pipe 5; a vibrating cyclone 3 is installed on the top of the primary desulfurization tower 1, and a flue gas cyclone chamber 11, a flue gas atomization chamber 12 and a desulfurization chamber 13 are sequentially arranged inside the primary desulfurization tower 1 from bottom to top; a permeable plate 131 is arranged between the desulfurization chamber 13 and the flue gas atomization chamber 12; wherein a counter-rotating unit is arranged in the flue gas cyclone chamber 11, and the counter-rotating unit can vertically transport the flue gas upward into the flue gas chamber along the axial direction of the primary desulfurization tower 1 A gas atomization chamber 12; an atomization mechanism 4 is arranged on the outer circumference of the flue gas atomization chamber 12, and the atomization mechanism 4 can provide mist water to the flue gas atomization chamber 12 and atomize and moisten the flue gas; the vibrating cyclone 3 can provide fine-grained carbide slag to the desulfurization chamber 13; a slag delivery mechanism is installed in the desulfurization chamber 13, and the slag delivery mechanism can evenly scatter the carbide slag on the air permeable plate 131; a plurality of through holes are arranged on the air permeable plate 131, and the through holes only allow the atomized and moistened flue gas to pass through; the secondary desulfurization tank 2 can use seawater to desulfurize the flue gas and discharge qualified flue gas and seawater.

[0029] As mentioned above, the vibrating cyclone 3 is an existing equipment purchased, also known as a vibrating screen, and the specific models are S49-600, S49-800 and S49-1000, which can be selected according to needs. This model of vibrating cyclone mainly includes a large particle cyclone layer 31, a fine particle cyclone layer 32, a carbide slag inlet 33, a large particle outlet 34 and a fine particle outlet 35, wherein the fine particle outlet 35 is connected to the slag delivery mechanism, which will not be described in detail.

[0030] As an embodiment of the present invention, the counter-rotating unit includes a gas transmission shunt pipe 114 and two sets of air supply mechanisms, wherein the air supply mechanism includes a fairing 111 and an impeller 113 driven by a motor A112, the motor A112 is horizontally fixed in the fairing 111, the fairing 111 is connected to the gas transmission shunt pipe 114; the two impellers 113 are arranged oppositely. When the motor A112 drives the impeller 113 to rotate, the flue gas enters the fairing 111 from the gas transmission shunt pipe 114, and the fairing 111 has a concentrating effect on the flue gas. Then, the flue gas is pulled by the wind pressure formed by the impeller 113, and passes through the axis of the primary desulfurization tower 1 along the axial direction of the impeller 113. Due to the relative arrangement of the two impellers 113, the flue gas can enter the flue gas atomization chamber 12 along the axis of the primary desulfurization tower 1 and vertically upward.

[0031] As an embodiment of the present invention, the atomizing mechanism 4 includes an annular shell 45, on which a plurality of fans 43 are installed, a clean water tank 44 is arranged at the bottom of the shell 45, a wet film material 41 is arranged opposite to the fan 43, and the clean water tank 44 injects water into the wet film material 41 through a water pump 42; a plurality of atomizing holes 121 are opened on the outer wall of the smoke atomizing chamber 12, and the atomizing holes 121 correspond to the positions of the wet film material 41, and the wet film material 41 is fixed on the outer wall of the smoke atomizing chamber 12. The wet film material 41 here is an existing material, which is also called "Seidek" material, and is the core of the wet film humidifier, containing a slow-release antibacterial agent. It is based on plant fiber, and is sintered by a resin with special components to form a corrugated plate-shaped cross-overlapping polymer composite material, which has the advantages of strong water absorption, good self-cleaning ability, non-toxicity, acid and alkali resistance, mildew resistance, flame retardancy, etc. The wet film material 41 is humidified by a dripping and soaking type method. Clean water is sent to the upper end of the wet film material 41 through a water pump 42. Under the action of gravity, the clean water penetrates downward along the surface of the wet film material 41 and is fully absorbed by the wet film material 41. Since the wet film material 41 has excellent water absorption, a uniform water film is formed. When the fan 41 passes dry air through the wet film material 41, the air is moistened and atomized and sent to the smoke atomization chamber 12.

[0032] As an embodiment of the present invention, the slag conveying mechanism includes a collecting trough 136, which is connected to the vibrating cyclone 3, and a discharge hopper is arranged at the lower end of the collecting trough 136. A rotatable rotating shaft 135 is arranged in the middle of the collecting trough 136, and a plurality of equalizing plates 133 are fixed to the lower end of the rotating shaft 135, and the radial dimension of the equalizing plate 133 is the inner diameter of the primary desulfurization tower 1; a sieve plate 134 is sealed below the equalizing plate 133, and the equalizing plate 133 can slide on the upper end surface of the sieve plate 134; a slag discharge port 132 is arranged on one side of the sieve plate 134.

[0033] Preferably, the cross section of the dividing plate 133 is arc-shaped.

[0034] Preferably, a driven pulley 135-1 is provided on the top of the rotating shaft 135, a motor B135-2 is provided on the outer wall of the desulfurization chamber 13, a driving pulley 135-3 is provided on the motor B, and the driving pulley 135-3 drives the driven pulley 135-1 to rotate through a belt. Figure 2 As shown, the rotating shaft 135, the driven pulley 135-1 and the belt are protected by a protective cover to prevent carbide slag from affecting the belt transmission.

[0035] Preferably, vibration motors 137 are installed on both sides of the collecting trough 136 to ensure that the carbide slag falls from the collecting trough 136 onto the sieve plate 134 .

[0036] As an embodiment of the present invention, the secondary desulfurization tank 2 is divided into a seawater absorption tank 21 and an aeration tank 22 which are connected from top to bottom, and the delivery pipe 5 is connected to the seawater absorption tank 21 .

[0037] Preferably, a conical conveying cover 51 is provided at the gas outlet end of the conveying pipe 5 , and the conveying cover 51 extends into the seawater in the seawater absorption tank 21 .

[0038] Preferably, a smoke outlet 213 is provided at the top of the seawater absorption tank 21, a water inlet 212 is provided at one side of the seawater absorption tank 21, a pH online monitor 211 is installed on the side wall of the seawater absorption tank 21, and a drain outlet A214 is provided at the lower end of the seawater absorption tank 21. The pH online monitor 211 here is an existing device that can detect and display the pH value of the seawater in the seawater absorption tank 21 at any time. After the flue gas passes through the secondary desulfurization of the seawater, it is discharged through the smoke outlet 213.

[0039] Preferably, an air inlet pipe 222 is provided at the bottom of the aeration tank 22, and a plurality of aerators 221 are provided on the air inlet pipe 222, and a drain port B223 is provided on one side of the aeration tank 22. When the pH of the seawater in the seawater absorption tank 21 reaches 3 to 4, it enters the aeration tank 22 through the drain port A214, and air is transported through the aerator 221. The oxygen in the air can oxidize the nitrite ions and sulfite ions in the seawater to form nitrate ions and sulfate ions, which are then neutralized by the alkaline substances in the seawater, thereby restoring the seawater, and after passing the test, it is discharged through the drain port B223.

[0040] The working process of the present invention is that the vibrating cyclone 3 at the top of the primary desulfurization tower 1 is provided with two cyclone layers from top to bottom, namely, a large particle cyclone layer 31 and a fine particle cyclone layer 32. The separated large particles are discharged through the large particle outlet 34, and the fine particles enter the collecting tank 136 in the desulfurization chamber 13 along the pipeline through the fine particle outlet 35. Under the vibration action of the vibration motor 137, the fine particles in the collecting tank 136 enter the equalizing plate 133, and the equalizing plate 133 rotates under the drive of the rotating shaft 135. The calcium carbide slag passes through the sieve plate 134 and falls on the air permeable plate 131. The moist flue gas passes through the air permeable plate 131 from bottom to top, and the primary desulfurization is realized through the calcium carbide slag; after a period of desulfurization, the calcium carbide slag is discharged and processed from the slag discharge port 132, and then the calcium carbide slag is re-laid through the vibrating cyclone 3 and the equalizing plate 133. The flue gas passing through the desulfurization chamber 13 is transported to the secondary desulfurization tank 2 through the conveying pipe 5. A conveying hood 51 is provided at the end of the conveying pipe 5 and extends into the seawater absorption tank 21. A pH online monitor 211 is provided on the side wall of the seawater absorption tank 21. When the pH of the seawater reaches 3-4, the seawater in the seawater absorption tank 21 enters the aeration tank 22 through the drain port A214 to recover the seawater. After passing the test, the seawater is discharged centrally through the drain port B223, and the flue gas from the secondary desulfurization is discharged through the exhaust port 213.

[0041] The present invention may be summarized in other specific forms that do not violate the spirit or main features of the present invention. Therefore, no matter from which point of view, the above embodiments of the present invention can only be regarded as an explanation of the present invention and cannot limit the present invention. The claims indicate the scope of the present invention, while the above description does not indicate the scope of the present invention. Therefore, any changes within the meaning and scope equivalent to the claims of the present invention should be considered to be included in the scope of the claims of the present invention.

Claims

1. A flue gas desulfurization system for biomass combustion, characterized in that: The invention comprises a primary desulfurization tower (1), wherein the top of the primary desulfurization tower (1) is connected to a secondary desulfurization tank (2) via a conveying pipe (5); a vibrating cyclone (3) is installed on the top of the primary desulfurization tower (1); a flue gas cyclone chamber (11), a flue gas atomization chamber (12) and a desulfurization chamber (13) are arranged in sequence from bottom to top inside the primary desulfurization tower (1); and a permeable plate (131) is arranged between the desulfurization chamber (13) and the flue gas atomization chamber (12); A counter-rotating unit is arranged in the flue gas cyclone chamber (11), and the counter-rotating unit is configured to be able to vertically transport the flue gas upwards into the flue gas atomization chamber (12) along the axial direction of the primary desulfurization tower (1); An atomizing mechanism (4) is provided on the outer circumference of the smoke atomizing chamber (12), and the atomizing mechanism (4) is configured to provide mist water to the smoke atomizing chamber (12) and atomize and moisten the smoke; The vibrating cyclone (3) is configured to provide fine-grained carbide slag to the desulfurization chamber (13); A slag conveying mechanism is installed in the desulfurization chamber (13), and the slag conveying mechanism is configured to evenly scatter the carbide slag on the air permeable plate (131); a plurality of through holes are provided on the air permeable plate (131), and the through holes are configured to only allow atomized and moistened flue gas to pass through; The secondary desulfurization tank (2) is configured to utilize seawater to desulfurize the flue gas and discharge qualified flue gas and seawater; The atomizing mechanism (4) comprises an annular outer shell (45), a plurality of fans (43) are mounted on the outer shell (45), a clean water tank (44) is arranged at the bottom of the outer shell (45), a wet film material (41) is arranged directly opposite the fan (43), and the clean water tank (44) injects water into the wet film material (41) through a water pump (42); a plurality of atomizing holes (121) are opened on the outer wall of the smoke atomizing chamber (12), the atomizing holes (121) correspond to the positions of the wet film material (41), and the wet film material (41) is fixed on the outer wall of the smoke atomizing chamber (12); The slag conveying mechanism comprises a collecting trough (136), the upper end of the collecting trough (136) is connected to the vibrating cyclone (3), the lower end of the collecting trough (136) is provided with a discharge hopper, a rotatable shaft (135) is provided in the middle of the collecting trough (136), a plurality of equalizing plates (133) are fixed to the lower end of the shaft (135), the radial dimension of the equalizing plates (133) being the inner diameter of the primary desulfurization tower (1); a sieve plate (134) is sealedly provided below the equalizing plate (133), the sieve plate (133) being configured to be able to slide on the upper end surface of the sieve plate (134); and a slag discharge port (132) is provided on one side of the sieve plate (134); Vibration motors (137) are installed on both sides of the collection tank (136).

2. The flue gas desulfurization system according to claim 1, characterized in that: The counter-rotating unit comprises an air supply shunt pipe (114) and two sets of air supply mechanisms, the air supply mechanism comprising a fairing (111) and an impeller (113) driven by a motor A (112), the motor A (112) being horizontally fixed in the fairing (111), the fairing (111) being connected to the air supply shunt pipe (114); the two impellers (113) are arranged opposite to each other.

3. The flue gas desulfurization system according to claim 1, characterized in that: A driven pulley (135-1) is arranged on the top of the rotating shaft (135), a motor B (135-2) is arranged on the outer wall of the desulfurization chamber (13), a driving pulley (135-3) is arranged on the motor B, and the driving pulley (135-3) drives the driven pulley (135-1) to rotate via a belt.

4. The flue gas desulfurization system according to any one of claims 1 to 3, characterized in that: The secondary desulfurization tank (2) is divided into a seawater absorption tank (21) and an aeration tank (22) which are connected from top to bottom, and the delivery pipe (5) is connected to the seawater absorption tank (21).

5. The flue gas desulfurization system according to claim 4, characterized in that: A conical conveying cover (51) is provided at the gas outlet end of the conveying pipe (5), and the conveying cover (51) is configured to extend into the seawater in the seawater absorption pool (21).

6. The flue gas desulfurization system according to claim 5, characterized in that: The top of the seawater absorption tank (21) is provided with a smoke exhaust port (213), one side of the seawater absorption tank (21) is provided with a water inlet (212), a pH online monitor (211) is installed on the side wall of the seawater absorption tank (21), and a drain port A (214) is provided at the lower end of the seawater absorption tank (21).

7. The flue gas desulfurization system according to claim 6, characterized in that: An air inlet pipe (222) is provided at the bottom of the aeration tank (22), a plurality of aerators (221) are provided on the air inlet pipe (222), and a drainage port B (223) is provided on one side of the aeration tank (22).

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