A multi-channel drying tower for solidifying desulfurization wastewater and a method of using the same

Abstract

The application discloses a kind of desulfurization wastewater solidification with multi-channel drying tower, it is related to wastewater treatment technical field.It includes drying tower, and drying tower includes evaporation drying flue gas inlet, flue gas bin, double fluid spray gun interface, drying tower flue gas outlet and ash discharge port;Annular partition plate is annularly separated into mist droplet change direction flue gas bin and wall-attached cyclone flue gas bin by flue gas bin;Mist droplet change direction flue gas inlet pipe, wall-attached cyclone flue gas inlet pipe are annularly arranged in sequence from inside to outside in the outer wall of evaporation drying flue gas inlet upper end;Mist droplet change direction flue gas outlet spout is annularly arranged in multiple in the bottom of mist droplet change direction flue gas bin, and wall-attached cyclone flue gas outlet spout is annularly arranged in multiple in the bottom of wall-attached cyclone flue gas bin;Double fluid spray gun interface is located below mist droplet change direction flue gas outlet spout and wall-attached cyclone flue gas outlet spout.The application efficiently completes the solidification of desulfurization wastewater, while effectively avoids scale blocking.The application also discloses the use method of the multi-channel drying tower for desulfurization wastewater solidification.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater treatment, more particularly, it is a multi-flow channel drying tower for desulfurization wastewater solidification. BACKGROUND

[0002] The desulfurization wastewater generated by the limestone-gypsum wet desulfurization of coal-fired power plants cannot be disposed of by most power plants due to its high suspended solids content, high salt content, high chloride ion concentration, and the presence of various heavy metals, complex pollutant composition, and large fluctuations in water quality and quantity. With increasingly stringent ecological and environmental protection requirements, the state is also increasing its control over power plant wastewater and has set a goal of "zero discharge" of power plant wastewater.

[0003] Currently, the desulfurization wastewater zero discharge process mainly uses the "pretreatment + concentration reduction + end solidification" technology. When the end solidification uses a two-phase flow atomization drying tower, the following problems exist:

[0004] 1) The concentrated desulfurization wastewater has a high hardness ion content, which can easily cause rapid nozzle wear and large atomized particle size during system operation.

[0005] 2) Changes in unit load can cause large fluctuations in the parameters of the concentrated liquid atomization drying flue gas, resulting in incomplete drying of the desulfurization wastewater concentrate droplets.

[0006] Therefore, during the operation of the desulfurization wastewater concentrate solidification system, wall sticking and scaling often occur on the inner wall of the drying tower, requiring high manual maintenance intensity. The two-fluid atomization nozzles need to be replaced frequently, resulting in high maintenance costs. In severe cases of scaling and clogging in the drying tower, the concentrated liquid solidification system may need to be shut down, and power plant operators may need to find new disposal channels for the unsolidified concentrate, thus failing to meet the demand for safe, stable, and reliable operation of the desulfurization wastewater concentrate solidification system in power plants.

[0007] Therefore, it is necessary to develop a desulfurization wastewater solidification multi-flow channel drying tower that can adapt to various actual working conditions, effectively prevent scaling and clogging, and reduce the replacement rate of multi-fluid gun nozzles. SUMMARY

[0008] The first object of the present application is to provide a multi-flow channel drying tower for desulfurization wastewater solidification to overcome the deficiencies of the prior art.

[0009] The second object of the present application is to provide a method for using the multi-flow channel drying tower for desulfurization wastewater solidification.

[0010] In order to achieve the above-mentioned first purpose, the technical scheme of the present application is: a multi-flow channel drying tower for desulfurization wastewater solidification, comprising a drying tower, characterized in that: the drying tower comprises an evaporation drying flue gas inlet with an upper end located above the top of the drying tower and a lower end extending into the interior of the drying tower, a flue gas bin annularly arranged between the inner wall of the top of the drying tower and the evaporation drying flue gas inlet, a double-fluid spray gun interface located on the side wall of the top of the drying tower, a drying tower flue gas outlet located on the side wall of the bottom of the drying tower, and a dust discharge port located at the bottom of the drying tower;

[0011] A ring-shaped partition plate annularly separates the flue gas bin from inside to outside into a mist droplet turning flue gas bin and a wall-attached cyclone flue gas bin;

[0012] The outer wall of the upper end of the evaporation drying flue gas inlet is annularly arranged from inside to outside with a mist droplet turning flue gas inlet pipe connected with the mist droplet turning flue gas bin and a wall-attached cyclone flue gas inlet pipe connected with the wall-attached cyclone flue gas bin;

[0013] A plurality of mist droplet turning flue gas outlet nozzles are annularly arranged at the bottom of the mist droplet turning flue gas bin, and a plurality of wall-attached cyclone flue gas outlet nozzles are annularly arranged at the bottom of the wall-attached cyclone flue gas bin; the outlet end of the wall-attached cyclone flue gas outlet nozzle faces the inner wall of the drying tower;

[0014] The double-fluid spray gun interface is located below the mist droplet turning flue gas outlet nozzle and the wall-attached cyclone flue gas outlet nozzle.

[0015] In the above technical scheme, a plurality of radial partition plates divide the mist droplet turning flue gas bin of the flue gas bin into a plurality of mist droplet turning flue gas individual bins and divide the wall-attached cyclone flue gas bin of the flue gas bin into a plurality of wall-attached cyclone flue gas individual bins;

[0016] A plurality of mist droplet turning flue gas outlet nozzles are arranged at the bottom of each mist droplet turning flue gas individual bin, and a plurality of wall-attached cyclone flue gas outlet nozzles are arranged at the bottom of each wall-attached cyclone flue gas individual bin.

[0017] In the above technical scheme, a plurality of mist droplet turning flue gas inlet branch pipes are annularly arranged at the bottom of the mist droplet turning flue gas inlet pipe, a plurality of wall-attached cyclone flue gas inlet branch pipes are annularly arranged at the bottom of the wall-attached cyclone flue gas inlet pipe, each mist droplet turning flue gas individual bin is connected with the corresponding mist droplet turning flue gas inlet branch pipe at the top, and each wall-attached cyclone flue gas individual bin is connected with the corresponding wall-attached cyclone flue gas inlet branch pipe at the top.

[0018] In the above technical scheme, in each mist droplet turning flue gas individual bin, the sum of the outlet cross-sectional areas of the plurality of mist droplet turning flue gas outlet nozzles is less than the sum of the cross-sectional areas of the plurality of mist droplet turning flue gas inlet branch pipes;

[0019] The sum of the outlet cross-sectional areas of the plurality of wall-attached cyclone flue gas outlet nozzles in each of the wall-attached cyclone flue gas chamber individual chambers is less than the sum of the cross-sectional areas of the plurality of wall-attached cyclone flue gas inlet branch pipes.

[0020] In the above technical solution, the outlet end direction of the wall-attached cyclone flue gas outlet nozzle is tangent to the inner wall of the drying tower at an angle of 30° downward, and the inlet end of the wall-attached cyclone flue gas outlet nozzle is a circular pipe and the outlet end is a flat pipe.

[0021] In the above technical solution, the cross section of the ring-shaped partition is in the shape of a "person" and the lower part of the wall-attached cyclone flue gas chamber and the mist droplet direction-changing flue gas chamber are inclined at an angle of 60°, and the side wall of the bottom of the drying tower is provided with a manhole for maintenance, and the side of the conical hopper at the bottom of the drying tower is provided with a rapping device.

[0022] In the above technical solution, the bottom side of the SCR reactor is connected with the high-temperature flue gas input pipe, the high-temperature flue gas pipeline is provided with a first baffle door and a fan, the high-temperature flue gas pipeline is divided into three routes, the first pipeline is connected with the evaporative drying flue gas inlet, the second pipeline is connected with the mist droplet direction-changing flue gas inlet pipe, and the third pipeline is connected with the wall-attached cyclone flue gas inlet pipe; the flue gas outlet of the drying tower is connected with the dust collector through a high-temperature flue gas discharge pipe, the high-temperature flue gas discharge pipe is provided with a second baffle door; and the bottom of the SCR reactor is connected with the dust collector.

[0023] In the above technical solution, the first pipeline is provided with a first electric butterfly valve, the second pipeline is provided with a second electric butterfly valve, and the third pipeline is provided with a third electric butterfly valve.

[0024] In order to achieve the above-mentioned second purpose, the technical solution of the present application is a use method of a multi-flow drying tower for desulfurization wastewater solidification, characterized by comprising the following steps:

[0025] Step 1: open the first baffle door and the second baffle door, open the third electric butterfly valve, and start the fan;

[0026] Step 2: the high-temperature flue gas after denitrification in the SCR reactor passes through the high-temperature flue gas pipeline, the third pipeline, the wall-attached cyclone flue gas inlet pipe, and the wall-attached cyclone flue gas inlet branch pipe in sequence through the fan, enters each wall-attached cyclone flue gas chamber individual chamber, and the high-temperature flue gas is sprayed out from the wall-attached cyclone flue gas chamber individual chamber through the wall-attached cyclone flue gas outlet nozzle towards the inner wall of the drying tower, forming a layer of cyclone wall-attached flue gas in the drying tower, and forming a wall-attached protection flue gas zone between the inner wall of the drying tower and the lower part of the wall-attached cyclone flue gas outlet nozzle.

[0027] Step 3: open the second electric butterfly valve and the first electric butterfly valve; after the second electric butterfly valve is opened, the high-temperature flue gas passes through the high-temperature flue gas pipeline, the second pipeline, the mist droplet direction-changing flue gas inlet pipe, and the mist droplet direction-changing flue gas inlet branch pipe in sequence and enters each mist droplet direction-changing flue gas single gas chamber, the high-temperature flue gas is sprayed out through the mist droplet direction-changing flue gas outlet spray pipe of the mist droplet direction-changing flue gas single gas chamber, and a circle of mist droplet direction-changing flue gas flow is formed along the outer side of the evaporation drying flue gas inlet pipe wall, and the mist droplet direction-changing flue gas flow forms a mist droplet direction-changing area in the area below the mist droplet direction-changing flue gas outlet spray pipe;

[0028] After the first electric butterfly valve is opened, the high-temperature flue gas passes through the high-temperature flue gas pipeline, the first pipeline, and the evaporation drying flue gas inlet into the drying tower in sequence, and the high-temperature flue gas forms a main evaporation drying flue gas area in the area below the evaporation drying flue gas inlet;

[0029] The area between the wall-attached protection flue gas area and the mist droplet direction-changing area is a drying buffer area;

[0030] Step 4: compressed air is supplied to the double-fluid spray gun, the concentrated liquid delivery pump is started, the desulfurization wastewater concentrate is delivered, the desulfurization wastewater concentrate is atomized by compressed air, and the nozzle of the double-fluid spray gun installed at the double-fluid spray gun interface sprays into the drying tower;

[0031] Step 5: the desulfurization wastewater concentrate droplets are first evaporated in the main evaporation drying flue gas area, and the particle size of the desulfurization wastewater concentrate droplets is reduced; then, the desulfurization wastewater concentrate droplets reach the mist droplet direction-changing area and are swept by the vertically downward mist droplet direction-changing flue gas flow, and the vertical downward component velocity of the desulfurization wastewater concentrate droplets increases; then, the desulfurization wastewater concentrate droplets enter the drying buffer area, and due to the increase in the vertical downward component velocity of the desulfurization wastewater concentrate droplets, the movement path of the desulfurization wastewater concentrate droplets is extended, and the desulfurization wastewater concentrate droplets are further evaporated and dried; the cyclone wall-attached flue gas in the wall-attached protection flue gas area moves spirally downward along the inner wall of the drying tower and sweeps the inner wall of the drying tower

[0032] Step 6: the desulfurization wastewater concentrate droplets are evaporated and dried to form dry ash, the dry ash moves with the high-temperature flue gas to the bottom of the drying tower, most of the dry ash is collected and precipitated in the cone at the bottom of the drying tower, is discharged through the unloading port under the action of the side rapping device of the cone, and a small amount of dry ash is sent into the dust collector together with the high-temperature flue gas through the high-temperature flue gas discharge pipe along with the high-temperature flue gas through the drying tower flue gas outlet at the side of the bottom of the drying tower; the solidification of the desulfurization wastewater is completed;

[0033] Step 7: the concentrated liquid delivery pump, the compressed air of the double-fluid spray gun, the second electric butterfly valve, and the first electric butterfly valve are closed in sequence;

[0034] Step 8: the fan, the third electric butterfly valve, the first baffle door, and the second baffle door are closed in sequence, and the system is shut down;

[0035] Step 9: During system shutdown, check the fouling condition of the inner wall of the drying tower through the manhole, if the initial fouling phenomenon is found, the next time the system is running, the blowing time of the outlet pipe of the wall-attached cyclone flue gas is extended after the fan is started, and the flue gas flow of the mist droplet deflection flue gas inlet pipe is increased.

[0036] In the above technical solution, in step 5, the opening of the second electric butterfly valve is adjusted according to the parameters of the flue gas measured at the outlet of the SCR reactor.

[0037] Compared with the prior art, the present application has the following advantages:

[0038] 1) In the present application, the hot air for drying is taken from the high-temperature flue gas at the bottom of the SCR reactor, without the need for additional heaters; the drying tower is an empty tower with top-in and bottom-out, which is simple in structure; the system is configured with one fan to ensure the amount of flue gas for drying the concentrated desulfurization wastewater mist, overcoming the problem of incomplete drying of the concentrated desulfurization wastewater mist in the tower caused by large changes in unit load.

[0039] 2) The drying tower of the present application has multiple inlet channels, forming a wall-attached protection flue gas zone, a drying buffer zone, a mist droplet deflection zone, and a main evaporation and drying flue gas zone in the tower; the concentrated desulfurization wastewater is atomized and sprayed into the drying tower by a double-fluid spray gun, the concentrated desulfurization wastewater mist is first evaporated in the main evaporation and drying flue gas zone, and the particle size of the mist droplet is reduced; when the mist droplet reaches the mist droplet deflection zone, it is swept by the high-speed vertical downward deflection airflow, and the vertical downward speed increases; when the mist droplet enters the drying buffer zone, due to the large vertical downward speed of the mist droplet, the movement path is greatly extended, and the mist droplet is further evaporated until it is dried; in the wall-attached protection flue gas zone, the high-temperature wall-attached cyclone flue gas moves downward at high speed along the inner wall of the drying tower in a spiral manner, effectively sweeping the inner wall of the drying tower; the high-efficiency drying of the concentrated desulfurization wastewater is effectively completed while fouling and blockage are effectively avoided.

[0040] 3) When the atomization effect of the double-fluid spray gun is poor due to nozzle wear and the flue gas parameters for drying change greatly, by adjusting the flue gas flow of the mist droplet deflection flue gas outlet pipe in the mist droplet deflection zone, the movement trajectory of the concentrated desulfurization wastewater mist droplet is effectively controlled, the evaporation and drying time of the concentrated desulfurization wastewater mist droplet is ensured, and the drying effect is ensured; at the same time, the flue gas flow of the wall-attached cyclone flue gas outlet pipe is adjusted to prevent fouling on the wall of the drying tower, forming a double-protection effect, reducing the replacement rate of the nozzles of the multi-fluid spray gun, and saving costs.

[0041] 4) The top of the drying tower is provided with adjacent wall-attached cyclone flue gas compartments and mist droplet deflection flue gas compartments, which are separated by a ring-shaped partition, so that the wall-attached cyclone flue gas and the mist droplet deflection flue gas are independent of each other; and the flue gas amount of the wall-attached cyclone flue gas and the mist droplet deflection flue gas can be flexibly adjusted according to the actual working conditions, and the system has a wide adjustment range.

[0042] 5) The droplet-deflecting flue gas inlet pipe and the wall-attached swirling flue gas inlet pipe of the present invention are both arranged in a circular shape. A plurality of droplet-deflecting flue gas inlet branch pipes are arranged in a circular shape at the bottom of the droplet-deflecting flue gas inlet pipe, and the plurality of droplet-deflecting flue gas inlet branch pipes are respectively led into the corresponding individual droplet-deflecting flue gas chambers; a plurality of wall-attached swirling flue gas inlet branch pipes are arranged in a circular shape at the bottom of the wall-attached swirling flue gas inlet pipe, and the plurality of wall-attached swirling flue gas inlet branch pipes are respectively led into the corresponding individual wall-attached swirling flue gas chambers, ensuring that the flue gas volume is evenly distributed in each individual droplet-deflecting flue gas chamber and each individual wall-attached swirling flue gas chamber, and thus forming a stable droplet-deflecting flue gas flow and a swirling wall-attached flue gas.

[0043] 6) The droplet-deflecting flue gas chamber of the present invention is divided into a plurality of individual droplet-deflecting flue gas chambers along the circumferential direction of the drying tower by a plurality of radial partitions. At the same time, each individual droplet-deflecting flue gas chamber is provided with a plurality of droplet-deflecting flue gas outlet nozzles, and the droplet-deflecting flue gas outlet nozzles are evenly arranged along the circumferential direction of the outer wall of the evaporation drying flue gas inlet pipe, effectively forming a stable ring of droplet-deflecting flue gas flow; moreover, the sum of the outlet cross-sectional areas of the plurality of droplet-deflecting flue gas outlet nozzles is smaller than the sum of the cross-sectional areas of the plurality of droplet-deflecting flue gas inlet branch pipes, so that the outlet flue gas flow velocity of the droplet-deflecting flue gas outlet nozzles is higher than the flue gas flow velocity at the evaporation drying flue gas inlet, which can effectively increase the downward movement component velocity of the desulfurization wastewater concentrate droplets, extend the movement path of the desulfurization wastewater concentrate droplets, increase the drying time of the desulfurization wastewater concentrate droplets, and slow down the risk of wet wall scaling when the desulfurization wastewater concentrate droplets are not dried well.

[0044] 7) The wall-attached swirling flue gas chamber of the present invention is divided into a plurality of individual wall-attached swirling flue gas chambers along the circumferential direction of the drying tower by a plurality of radial partitions. At the same time, each individual wall-attached swirling flue gas chamber is provided with a plurality of wall-attached swirling flue gas outlet nozzles, and the wall-attached swirling flue gas outlet nozzles are evenly arranged along the circumferential direction of the inner wall of the drying tower, and the outlet end direction of the wall-attached swirling flue gas outlet nozzles is tangent to the inner wall of the drying tower at a downward angle of 30°, ensuring the formation of a stable swirling wall-attached flue gas along the tower wall direction; moreover, the inlet end of the wall-attached swirling flue gas outlet nozzle is a round pipe and the outlet end is a flat pipe, and the sum of the outlet cross-sectional areas of the plurality of wall-attached swirling flue gas outlet nozzles is smaller than the sum of the cross-sectional areas of the plurality of wall-attached swirling flue gas inlet branch pipes, so that the outlet flue gas flow velocity of the wall-attached swirling flue gas outlet nozzles is high, forming a layer of high-speed swirling wind on the inner wall of the drying tower, which has a good purging effect on the initial ash accumulation formed by the possible wet wall of the tower wall.

[0045] 8) In the present invention, the cross-section of the circumferential partition is designed in a "human" shape, so the lower parts of the droplet-deflecting flue gas chamber and the wall-attached swirling flue gas chamber are inclined, and the inclination angle is about 60°, effectively avoiding the deposition of ash in the corresponding droplet-deflecting flue gas chamber and wall-attached swirling flue gas chamber.

[0046] 9) The first pipeline of the present application is provided with a first electric butterfly valve, the second pipeline is provided with a second electric butterfly valve, and the third pipeline is provided with a third electric butterfly valve, which are used to adjust the required flue gas according to the operating conditions, can flexibly adapt to various actual working conditions on site, and effectively avoid the scaling and plugging of the drying tower. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 It is a structural diagram of the drying tower.

[0048] Figure 2 It is a structural diagram of the mist droplet turning flue gas inlet pipe and the wall-attached cyclone flue gas inlet pipe.

[0049] Figure 3 It is a structural diagram of the mist droplet turning flue gas bin, wall-attached cyclone flue gas bin, and evaporation drying flue gas inlet.

[0050] Figure 4 It is a structural diagram of the mist droplet turning flue gas individual bin and wall-attached cyclone flue gas individual bin.

[0051] Figure 5 It is a cross-sectional flue gas distribution area diagram in the drying tower.

[0052] Figure 6 It is a structural diagram of the wall-attached cyclone flue gas outlet nozzle.

[0053] Figure 7 It is a connection relationship diagram of the drying tower, SCR reactor, and dust remover.

[0054] 1-drying tower, 11-evaporation drying flue gas inlet, 12-flue gas bin, 121-mist droplet turning flue gas bin, 1211-mist droplet turning flue gas outlet nozzle, 1212-mist droplet turning flue gas individual bin, 122-wall-attached cyclone flue gas bin, 1221-wall-attached cyclone flue gas outlet nozzle, 12211-circular pipe, 12212-flat pipe, 1222-wall-attached cyclone flue gas individual bin, 123-ring-shaped partition, 124-radial partition, 13-dual-fluid spray gun interface, 131-dual-fluid spray gun, 14-drying tower flue gas outlet, 15-ash discharge port, 161-mist droplet turning flue gas inlet pipe, 1611-mist droplet turning flue gas inlet branch pipe, 162-wall-attached cyclone flue gas inlet pipe, 1621-wall-attached cyclone flue gas inlet branch pipe, 17-inspection manhole, 18-rapping device, 2-SCR reactor, 21-high-temperature flue gas input pipe, 211-first baffle door, 212-fan, 22-first pipeline, 221-first electric butterfly valve, 23-second pipeline, 231-second electric butterfly valve, 24-third pipeline, 241-third electric butterfly valve, 3-dust remover, 31-high-temperature flue gas discharge pipe, 311-second baffle door, 41-wall-attached protection flue gas zone, 42-mist droplet turning zone, 43-main evaporation drying flue gas zone, 44-drying buffer zone. Detailed Implementation

[0055] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but these descriptions are not intended to limit the invention and are merely illustrative. The advantages of the present invention will become clearer and easier to understand through this description.

[0056] As can be seen from the attached diagram: Figure 1 As shown, a multi-channel drying tower for solidifying desulfurization wastewater includes a drying tower 1. The drying tower 1 includes an evaporation drying flue gas inlet 11 with its upper end located above the top of the drying tower 1 and its lower end extending into the interior of the drying tower 1, a flue gas chamber 12 arranged in a ring between the inner wall of the top of the drying tower 1 and the evaporation drying flue gas inlet 11, a dual-fluid spray gun interface 13 located on the side wall of the top of the drying tower 1, a drying tower flue gas outlet 14 located on the side wall of the bottom of the drying tower 1, and an ash discharge port 15 located at the bottom of the drying tower 1.

[0057] like Figure 3 As shown, the circumferential partition 123 divides the flue gas chamber 12 into a droplet-direction flue gas chamber 121 and a wall-mounted swirl flue gas chamber 122 from the inside out.

[0058] like Figure 1 and Figure 2 As shown, the outer wall of the upper end of the evaporation drying flue gas inlet 11 is arranged in a ring from the inside to the outside with a droplet-direction flue gas inlet pipe 161 connected to the droplet-direction flue gas chamber 121 and a wall-adhering swirl flue gas inlet pipe 162 connected to the wall-adhering swirl flue gas chamber 122.

[0059] like Figure 3 and Figure 4 As shown, the bottom of the droplet-directing flue gas chamber 121 is arranged with multiple droplet-directing flue gas outlet nozzles 1211, and the bottom of the wall-adhering swirl flue gas chamber 122 is arranged with multiple wall-adhering swirl flue gas outlet nozzles 1221. The outlet ends of the wall-adhering swirl flue gas outlet nozzles 1221 face the inner wall of the drying tower 1. The multiple droplet-directing flue gas outlet nozzles 1211 are evenly arranged circumferentially along the outer side of the evaporative drying flue gas inlet 11 pipe wall. The multiple wall-adhering swirl flue gas outlet nozzles 1221 are evenly arranged circumferentially along the inner wall of the drying tower 1.

[0060] like Figure 3 As shown, the dual-fluid spray gun interface 13 is located below the droplet-directing flue gas outlet nozzle 1211 and the wall-mounted swirling flue gas outlet nozzle 1221;

[0061] like Figure 5As shown, in the drying tower 1, the area between the inner wall of the drying tower 1 and the lower part of the wall-attached cyclone flue gas outlet nozzle 1221 is the wall-attached protection flue gas area 41, the area below the flue gas outlet nozzle 1211 of the droplet deflection area 42, and the area below the evaporation drying flue gas inlet 11 is the main evaporation drying flue gas area 43. The area between the wall-attached protection flue gas area 41 and the droplet deflection area 42 is the drying buffer area 44.

[0062] As shown, the plurality of radial partitions 124 divides the droplet deflection flue gas warehouse 121 of the flue gas warehouse 12 into a plurality of droplet deflection flue gas single warehouses 1212, and divides the wall-attached cyclone flue gas warehouse 122 of the flue gas warehouse 12 into a plurality of wall-attached cyclone flue gas single warehouses 1222. Figure 4

[0063] Each of the droplet deflection flue gas single warehouses 1212 is provided with a plurality of droplet deflection flue gas outlet nozzles 1211 at the bottom, and each of the wall-attached cyclone flue gas single warehouses 1222 is provided with a plurality of wall-attached cyclone flue gas outlet nozzles 1221 at the bottom.

[0064] The bottom of the droplet deflection flue gas inlet pipe 161 is annularly arranged with a plurality of droplet deflection flue gas inlet branch pipes 1611, and the bottom of the wall-attached cyclone flue gas inlet pipe 162 is annularly arranged with a plurality of wall-attached cyclone flue gas inlet branch pipes 1621. The top of each of the droplet deflection flue gas single warehouses 1212 is connected with a plurality of droplet deflection flue gas inlet branch pipes 1611, and the top of each of the wall-attached cyclone flue gas single warehouses 1222 is connected with a plurality of wall-attached cyclone flue gas inlet branch pipes 1621.

[0065] In each of the droplet deflection flue gas single warehouses 1212, the sum of the outlet cross-sectional areas of the plurality of droplet deflection flue gas outlet nozzles 1211 is less than the sum of the cross-sectional areas of the plurality of droplet deflection flue gas inlet branch pipes 1611, so as to increase the outlet flue gas flow rate of the droplet deflection flue gas outlet nozzle 1211, increase the downward movement speed of the droplets, prolong the movement path of the droplets to the wall surface, increase the drying time of the droplets, and slow down the risk of wet wall scaling when the droplets are not dried well.

[0066] In each of the wall-attached cyclone flue gas single warehouses 1222, the sum of the outlet cross-sectional areas of the plurality of wall-attached cyclone flue gas outlet nozzles 1221 is less than the sum of the cross-sectional areas of the plurality of wall-attached cyclone flue gas inlet branch pipes 1621, so as to increase the outlet flue gas flow rate of the wall-attached cyclone flue gas outlet nozzle 1221, and form a layer of high-speed cyclone wind on the wall of the drying tower 1, which has a good sweeping effect on the initial dust accumulated on the wall.

[0067] As shown, Figure 6 ​As shown, the outlet end direction of the wall-attached swirling flue gas outlet nozzle 1221 is tangent to the inner wall of the drying tower 1 at a downward angle of 30°; the inlet end of the wall-attached swirling flue gas outlet nozzle 1221 is a circular pipe 12211, and the outlet end is a flat pipe 12212; thereby increasing the flue gas flow velocity at the outlet of the wall-attached swirling flue gas outlet nozzle 1221, and realizing the formation of a thin layer of high-speed spiral downward swirling wind on the wall of the drying tower 1.

[0068] As Figure 3 As shown, the cross-section of the circumferential baffle 123 is in a "human" shape, and the lower parts of the droplet-deflecting flue gas chamber 121 and the wall-attached swirling flue gas chamber 122 are inclined, with an inclination angle of about 60°, to prevent ash in the flue gas from depositing in the droplet-deflecting flue gas chamber 121 and the wall-attached swirling flue gas chamber 122; a maintenance manhole 17 is provided on the side wall at the bottom of the drying tower 1, and a vibrator 18 is provided on the side of the bottom hopper of the drying tower 1. The bottom of the drying tower 1 is a hopper, and the vibrator 18 is used to vibrate the hopper to prevent ash accumulation at the bottom and facilitate the discharge of the bottom ash.

[0069] As Figure 7 As shown, the bottom side of the SCR reactor 2 is connected to the high-temperature flue gas inlet pipe 21. A first baffle door 211 and a fan 212 are provided on the high-temperature flue gas pipe 21. The high-temperature flue gas pipe 21 is divided into three paths. The first path 22 is connected to the evaporation drying flue gas inlet 11, the second path 23 is connected to the droplet-deflecting flue gas inlet pipe 161, and the third path 24 is connected to the wall-attached swirling flue gas inlet pipe 162; the drying tower flue gas outlet 14 is connected to the dust collector 3 through the high-temperature flue gas discharge pipe 31, and a second baffle door 311 is provided on the high-temperature flue gas discharge pipe 31; the bottom of the SCR reactor 2 is connected to the dust collector 3.

[0070] As Figure 7 As shown, a first electric butterfly valve 221 is provided on the first path 22, a second electric butterfly valve 231 is provided on the second path 23, and a third electric butterfly valve 241 is provided on the third path 24.

[0071] A method for using a multi-channel drying tower for desulfurization wastewater solidification, comprising the following steps: [[ID=ID=19]]

[0072] Step 1: Open the first baffle door 211 and the second baffle door 311, open the third electric butterfly valve 241, start the fan 212, and run for 3 - 5 minutes;

[0073] Step 2: The high-temperature flue gas after denitration from the SCR reactor 2 passes through the high-temperature flue gas pipeline 21, the third pipeline 24, the wall-attached cyclone flue gas inlet pipe 162, and the wall-attached cyclone flue gas inlet branch pipe 1621 in sequence by the fan 212, and enters each wall-attached cyclone flue gas chamber individual gas chamber 1222. The high-temperature flue gas is sprayed out through the wall-attached cyclone flue gas outlet nozzle 1221 of the wall-attached cyclone flue gas chamber individual gas chamber 1222 towards the inner wall of the drying tower 1, and forms a layer of high-speed and stable cyclone wall-attached flue gas spirally downward on the inner wall of the drying tower 1 to sweep the inner wall of the drying tower 1; the cyclone wall-attached flue gas forms a wall-attached protection flue gas area 41 in the area between the inner wall of the drying tower 1 and below the wall-attached cyclone flue gas outlet nozzle 1221.

[0074] Step 3: Open the second electric butterfly valve 231 and the first electric butterfly valve 221; after the second electric butterfly valve 231 is opened, the high-temperature flue gas passes through the high-temperature flue gas pipeline 21, the second pipeline 23, the mist droplet turning flue gas inlet pipe 161, and the mist droplet turning flue gas inlet branch pipe 1611 in sequence, and enters each mist droplet turning flue gas individual gas chamber 1212. The high-temperature flue gas is sprayed out through the mist droplet turning flue gas outlet nozzle 1211 of the mist droplet turning flue gas individual gas chamber 1212, and forms a circle of mist droplet turning flue gas flow along the outer side of the evaporation drying flue gas inlet 11 pipe wall. The mist droplet turning flue gas flow forms a mist droplet turning area 42 in the area below the mist droplet turning flue gas outlet nozzle 1211.

[0075] After the first electric butterfly valve 221 is opened, the high-temperature flue gas passes through the high-temperature flue gas pipeline 21, the first pipeline 22, and the evaporation drying flue gas inlet 11 in sequence, and enters the drying tower 1. The high-temperature flue gas forms a main evaporation drying flue gas area 43 in the area below the evaporation drying flue gas inlet 11.

[0076] The area between the wall-attached protection flue gas area 41 and the mist droplet turning area 42 is a drying buffer area 44.

[0077] Step 4: Compressed air is supplied to the double-fluid spray gun 131, and the concentrated liquid delivery pump is started to deliver the desulfurization wastewater concentrate. The desulfurization wastewater concentrate is atomized by compressed air, and sprayed into the drying tower 1 through the nozzle of the double-fluid spray gun 131 installed at the double-fluid spray gun interface 13.

[0078] Step 5: The desulfurization wastewater concentrate liquid droplets have horizontal separation velocity (from the center of the drying tower 1 to the wall of the drying tower 1) and vertical downward separation velocity (from the top of the drying tower 1 to the bottom of the drying tower 1), the desulfurization wastewater concentrate liquid droplets are first evaporated in the main evaporation and drying flue gas zone 43, and the particle size of the desulfurization wastewater concentrate liquid droplets is reduced; then, the desulfurization wastewater concentrate liquid droplets reach the mist droplet turning zone 42 and are blown by the vertical downward mist droplet turning flue gas flow, and the vertical downward separation velocity of the desulfurization wastewater concentrate liquid droplets is increased; then, the desulfurization wastewater concentrate liquid droplets enter the drying buffer zone 44, and due to the increase of the vertical downward separation velocity of the desulfurization wastewater concentrate liquid droplets, the movement path of the desulfurization wastewater concentrate liquid droplets is greatly extended, and the desulfurization wastewater concentrate liquid droplets are further evaporated and dried; the cyclone wall-attached flue gas of the wall-attached protection flue gas zone 41 moves spirally along the inner wall of the drying tower 1 and sweeps the inner wall of the drying tower 1

[0079] Step 6: The desulfurization wastewater concentrate liquid droplets are evaporated and dried to form dry ash mainly composed of salt, the dry ash moves with the high-temperature flue gas to the bottom of the drying tower 1, most of the dry ash is collected and precipitated in the cone at the bottom of the drying tower 1, and is discharged outside through the ash discharge port 15 under the action of the rapping device 18, a small amount of dry ash is sent into the dust collector 3 together with the high-temperature flue gas through the high-temperature flue gas discharge pipe 31 with the high-temperature flue gas outlet 14 at the side of the bottom of the drying tower 1, the flue gas after being dedusted by the dust collector 3 enters the subsequent desulfurization system for further desulfurization; and the solidification of the desulfurization wastewater is completed.

[0080] Step 7: The concentrate liquid delivery pump, the compressed air of the double-fluid spray gun 131, the second electric butterfly valve 231 and the first electric butterfly valve 221 are closed in sequence, and maintained for 3-5 min.

[0081] Step 8: The fan 212, the third electric butterfly valve 241, the first baffle door 211 and the second baffle door 311 are closed in sequence, and the system is shut down.

[0082] Step 9: During the system shutdown, the scaling condition of the inner wall of the drying tower 1 is checked regularly through the maintenance manhole 17, if the initial scaling phenomenon is found, the sweeping time of the wall-attached cyclone flue gas outlet spout 1221 is prolonged and the flue gas amount of the mist droplet turning flue gas inlet pipe 161 is increased after the fan 212 is started next time.

[0083] In step 5, the opening degree of the second electric butterfly valve 231 is adjusted according to the parameters of the flue gas measured at the outlet of the SCR reactor 2.

[0084] The other parts not described belong to the prior art.

Claims

1. A multi-channel drying tower for solidification of desulfurization wastewater, comprising a drying tower (1), characterized in that: The drying tower (1) comprises an evaporation drying flue gas inlet (11) with its upper end above the top of the drying tower (1) and its lower end extending into the interior of the drying tower (1), a flue gas bin (12) annularly arranged between the inner wall of the top of the drying tower (1) and the evaporation drying flue gas inlet (11), a double-fluid spray gun interface (13) located on the side wall of the top of the drying tower (1), a drying tower flue gas outlet (14) located on the side wall of the bottom of the drying tower (1), and a dust discharging port (15) located at the bottom of the drying tower (1); The flue gas bin (12) is annularly divided into a mist droplet direction-changing flue gas bin (121) and a wall-attached cyclone flue gas bin (122) from inside to outside by a ring-shaped partition plate (123); The outer wall of the upper end of the evaporation drying flue gas inlet (11) is annularly arranged from inside to outside with a mist droplet direction-changing flue gas inlet pipe (161) connected with the mist droplet direction-changing flue gas bin (121) and a wall-attached cyclone flue gas inlet pipe (162) connected with the wall-attached cyclone flue gas bin (122); The bottom of the mist droplet direction-changing flue gas bin (121) is annularly arranged with a plurality of mist droplet direction-changing flue gas outlet nozzles (1211), and the bottom of the wall-attached cyclone flue gas bin (122) is annularly arranged with a plurality of wall-attached cyclone flue gas outlet nozzles (1221); the outlet end of the wall-attached cyclone flue gas outlet nozzle (1221) faces the inner wall of the drying tower (1); The double-fluid spray gun interface (13) is located below the mist droplet direction-changing flue gas outlet nozzle (1211) and the wall-attached cyclone flue gas outlet nozzle (1221).

2. A multi-channel drying column for solidifying desulfurization wastewater according to claim 1, characterized in that: A plurality of radial partition plates (124) divide the mist droplet direction-changing flue gas bin (121) of the flue gas bin (12) into a plurality of mist droplet direction-changing flue gas individual bins (1212) and divide the wall-attached cyclone flue gas bin (122) of the flue gas bin (12) into a plurality of wall-attached cyclone flue gas individual bins (1222); The bottom of each mist droplet direction-changing flue gas individual bin (1212) is provided with a plurality of mist droplet direction-changing flue gas outlet nozzles (1211), and the bottom of each wall-attached cyclone flue gas individual bin (1222) is provided with a plurality of wall-attached cyclone flue gas outlet nozzles (1221).

3. A multi-channel drying column for solidifying desulfurization wastewater according to claim 2, characterized in that: The bottom of the mist droplet direction-changing flue gas inlet pipe (161) is annularly arranged with a plurality of mist droplet direction-changing flue gas inlet branch pipes (1611), and the bottom of the wall-attached cyclone flue gas inlet pipe (162) is annularly arranged with a plurality of wall-attached cyclone flue gas inlet branch pipes (1621); the top of each mist droplet direction-changing flue gas individual bin (1212) is connected with the corresponding mist droplet direction-changing flue gas inlet branch pipe (1611), and the top of each wall-attached cyclone flue gas individual bin (1222) is connected with the corresponding wall-attached cyclone flue gas inlet branch pipe (1621).

4. The multi-channel drying column for solidifying desulfurization wastewater according to claim 3, characterized in that: In each mist droplet direction-changing flue gas individual bin (1212), the sum of the outlet cross-sectional areas of the plurality of mist droplet direction-changing flue gas outlet nozzles (1211) is less than the sum of the cross-sectional areas of the plurality of mist droplet direction-changing flue gas inlet branch pipes (1611); In each wall-attached cyclone flue gas individual bin (1222), the sum of the outlet cross-sectional areas of the plurality of wall-attached cyclone flue gas outlet nozzles (1221) is less than the sum of the cross-sectional areas of the plurality of wall-attached cyclone flue gas inlet branch pipes (1621).

5. The multi-channel drying column for solidifying desulfurization wastewater according to claim 1, characterized in that: The outlet end direction of the wall-attached cyclone flue gas outlet nozzle (1221) is tangent to the inner wall of the drying tower (1) at a downward angle of 30°; the inlet end of the wall-attached cyclone flue gas outlet nozzle (1221) is a circular tube (1341), and the outlet end is a flat tube (1342).

6. A multi-channel drying column for solidifying desulfurization wastewater according to claim 1, characterized in that: The cross section of the ring-shaped partition plate (123) is in the shape of a "human" figure, the lower part of the mist droplet changing direction flue gas bin (121) and the wall-attached cyclone flue gas bin (122) are inclined, and the inclination angle is 60°; a manhole (17) is arranged on the side wall of the bottom of the drying tower (1), and a rapping device (18) is arranged on the side of the bottom cone of the drying tower (1).

7. A multi-channel drying column for solidifying desulfurization wastewater according to claim 1, characterized in that: The bottom side of the SCR reactor (2) is connected with the high-temperature flue gas input pipe (21), the first baffle door (211) and the fan (212) are arranged on the high-temperature flue gas input pipe (21), the high-temperature flue gas input pipe (21) is divided into three routes, the first pipe (22) is connected with the evaporative drying flue gas inlet (11), the second pipe (23) is connected with the mist droplet changing direction flue gas inlet pipe (161), and the third pipe (24) is connected with the wall-attached cyclone flue gas inlet pipe (162); the drying tower flue gas outlet (14) is connected with the dust collector (3) through the high-temperature flue gas discharge pipe (31), the second baffle door (311) is arranged on the high-temperature flue gas discharge pipe (31); the bottom of the SCR reactor (2) is connected with the dust collector (3).

8. A multi-channel drying column for solidifying desulfurization wastewater according to claim 7, characterized in that: The first electric butterfly valve (221) is arranged on the first pipe (22), the second electric butterfly valve (231) is arranged on the second pipe (23), and the third electric butterfly valve (241) is arranged on the third pipe (24).

9. A method for using a multi-channel drying tower for solidification of desulfurization wastewater, characterized by, The method comprises the following steps: Step 1: open the first baffle door (211) and the second baffle door (311), open the third electric butterfly valve (241), and start the fan (212); Step 2: the high-temperature flue gas after denitrification from the SCR reactor (2) enters each wall-attached cyclone flue gas bin single bin (1222) through the fan (212) in sequence through the high-temperature flue gas input pipe (21), the third pipe (24), the wall-attached cyclone flue gas inlet pipe (162), and the wall-attached cyclone flue gas inlet branch pipe (1621), the high-temperature flue gas is sprayed out from the wall-attached cyclone flue gas outlet nozzle (1221) of the wall-attached cyclone flue gas bin single bin (1222) towards the inner wall of the drying tower (1), the high-temperature flue gas forms a layer of cyclone wall-attached flue gas in the inner wall of the drying tower (1), and the cyclone wall-attached flue gas forms a wall-attached protection flue gas area (41) between the inner wall of the drying tower (1) and the lower part of the wall-attached cyclone flue gas outlet nozzle (1221); Step 3: open the second electric butterfly valve (231) and the first electric butterfly valve (221); after the second electric butterfly valve (231) is opened, the high-temperature flue gas passes through the high-temperature flue gas input pipe (21), the second pipeline (23), the mist droplet turning flue gas inlet pipe (161), the mist droplet turning flue gas inlet branch pipe (1611) in sequence and enters each mist droplet turning flue gas single gas chamber (1212), the high-temperature flue gas is sprayed out through the mist droplet turning flue gas outlet spray pipe (1211) of the mist droplet turning flue gas single gas chamber (1212), a circle of mist droplet turning flue gas flow is formed along the outer side of the evaporation drying flue gas inlet (11) pipe wall, the mist droplet turning flue gas flow forms a mist droplet turning area (42) in the area below the mist droplet turning flue gas outlet spray pipe (1211); After the first electric butterfly valve (221) is opened, the high-temperature flue gas passes through the high-temperature flue gas input pipe (21), the first pipeline (22), the evaporation drying flue gas inlet (11) in sequence and enters the drying tower (1), the high-temperature flue gas forms a main evaporation drying flue gas area (43) in the area below the evaporation drying flue gas inlet (11); The area between the wall-attached protection flue gas area (41) and the mist droplet turning area (42) is a drying buffer area (44); Step 4: compressed air is input into the double-fluid spray gun (131), the concentrated liquid delivery pump is started, the desulfurization wastewater concentrate is delivered, the desulfurization wastewater concentrate is atomized by compressed air, and the desulfurization wastewater concentrate is sprayed into the drying tower (1) through the nozzle of the double-fluid spray gun (131) installed at the double-fluid spray gun interface (13); Step 5: the desulfurization wastewater concentrate mist droplet is first evaporated in the main evaporation drying flue gas area (43), the particle size of the desulfurization wastewater concentrate mist droplet is reduced; then, the desulfurization wastewater concentrate mist droplet reaches the mist droplet turning area (42) and is swept by the vertically downward mist droplet turning flue gas flow, the vertical downward component velocity of the desulfurization wastewater concentrate mist droplet is increased; then, the desulfurization wastewater concentrate mist droplet enters the drying buffer area (44), due to the increase of the vertical downward component velocity of the desulfurization wastewater concentrate mist droplet, the movement path of the desulfurization wastewater concentrate mist droplet is prolonged, and the desulfurization wastewater concentrate mist droplet is further evaporated and dried; the cyclone wall-attached flue gas of the wall-attached protection flue gas area (41) moves spirally downward along the inner wall of the drying tower (1) and sweeps the inner wall of the drying tower (1); Step 6: the desulfurization wastewater concentrate mist droplet is evaporated and dried to form dry ash, the dry ash moves to the bottom of the drying tower (1) with the high-temperature flue gas, most of the dry ash is collected and precipitated in the cone at the bottom of the drying tower (1), and is discharged outside through the ash discharge port (15) under the action of the rapping device (18), a small amount of dry ash passes through the drying tower flue gas outlet (14) at the side of the bottom of the drying tower (1) and is sent into the dust collector (3) with the high-temperature flue gas through the high-temperature flue gas discharge pipe (31); the solidification of the desulfurization wastewater is completed; Step 7: the concentrated liquid delivery pump, the compressed air of the double-fluid spray gun (131), the second electric butterfly valve (231) and the first electric butterfly valve (221) are closed in sequence; Step 8: the fan (212), the third electric butterfly valve (241), the first baffle door (211) and the second baffle door (311) are closed in sequence, and the system is shut down. Step 9: During system shutdown, through the manhole (17), the fouling of the inner wall of the drying tower (1) is checked regularly. If initial fouling is found, the next time the system is running, the purging time of the wall-attached cyclone flue gas outlet nozzle (1221) is extended after the fan (212) is started, and the flue gas flow of the mist droplet deflection flue gas inlet pipe (161) is increased.

10. The method of using a multi-channel drying column for solidifying desulfurization wastewater according to claim 9, characterized in that, In step 5, according to the parameters of the flue gas measured at the outlet of the SCR reactor (2), the opening of the second electric butterfly valve (231) is adjusted.

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