Load-adaptive efficient absorption tower

Abstract

The utility model discloses a self-adaptive load efficient absorption tower which comprises a tower body, a flue gas inlet and a flue gas outlet are arranged on the tower body, flue gas enters the tower body from the flue gas inlet and flows to the flue gas outlet from bottom to top, and a slurry pond is formed below the flue gas inlet of the tower body; a porous tray, a spraying layer and a demister are sequentially arranged on a flue gas flowing path in the flowing direction, a side wall cover plate for adjusting the flue gas flowing area at the porous tray along with a flue gas treatment load is arranged at the porous tray in the circumferential direction, and the lower end of the side wall cover plate is in running fit connection with the inner wall of the tower body at the edge of the porous tray. An adjusting mechanism for adjusting the rotating angle of the side wall cover plate is arranged in the tower body; according to the utility model, the flue gas circulation area can be adjusted, the self-adaptive change adjustment of the absorption tower along with the flue gas treatment load is realized, and the flue gas desulfurization treatment effect is ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of absorption tower, specifically relates to a self -adaptation load's high -efficient absorption tower. BACKGROUND

[0002] In today's growing emphasis on environmental protection, coal-fired power plants and other major emitters face more stringent ultra-low emission requirements. In order to meet these requirements, desulfurization absorption tower as the core equipment of flue gas desulfurization, its design and operation efficiency become the key.

[0003] At present, the desulfurization absorption tower generally adopts the structure design of multiple spray layers plus porous trays. The spray absorption tower is sequentially from the bottom up slurry pool area, SO2 absorption area and demisting area. The flue gas enters the absorption tower from the lower part of the absorption area, passes through the porous tray and several layers of spray layer in turn, each spray layer is arranged with multiple atomizing nozzles, the slurry is atomized by the nozzle and sprayed downward and dispersed in mist form through the absorption area, and contacts and mass transfer with the countercurrent flue gas. After the gas-liquid contact, the flue gas carries a large amount of liquid droplets, which are separated by the demister in the demisting area at the upper part of the absorption tower, and then discharged from the absorption tower. The bottom of the absorption tower is the slurry pool area, the function of the slurry pool is to accept and store the absorption slurry, dissolve limestone, blow oxygen to CaSO3, and crystallize to generate gypsum.

[0004] At present, the national ultra-low emission requirement of flue gas pollutants in thermal power plants is that the concentration of sulfur dioxide is not higher than 35 mg / Nm 3 , and the concentration of particulate matter is not higher than 5 mg / Nm 3 . In order to meet this requirement, the desulfurization absorption tower is generally designed according to the number of slurry spray layers and the amount of spray under full load operation of the unit, and the tray opening rate is designed according to the corresponding spray amount to form a liquid layer with appropriate thickness. In most cases, the spray layer is designed as 4-5 layers, and the tray opening rate is designed as 30-40%. This structure meets the demand of ultra-low emission to a certain extent, but with the continuous improvement of environmental protection standards and the diversification of unit operation conditions, especially under the requirement of national policy for deep peak shaving and flexible operation of thermal power units, its limitations gradually appear.

[0005] The design of evenly arranging multiple atomizing nozzles on the spray layer results in less slurry coverage near the wall area of the absorption tower than in the central area, and a large amount of slurry flows downward along the inner wall of the absorption tower without achieving the effect of atomizing absorption. In addition, in many projects, in order to prevent the long-term direct scouring of the absorption tower wall by the nozzles near the wall, the number of wall-attached nozzles is intentionally reduced or the direction of the wall-attached nozzles is adjusted, which further reduces the slurry coverage near the wall area of the absorption tower. In this way, a ring-shaped flue gas "short circuit area" near the wall is formed on the cross section of the absorption tower, in which the flue gas is not fully washed by the absorption slurry and is directly discharged outside the absorption tower, greatly reducing the desulfurization efficiency. Taking a desulfurization absorption tower matched with a 300 MW thermal power unit as an example, the cross-sectional diameter of the absorption zone of the absorption tower is 12 m, and engineering tests show that the desulfurization efficiency in the central area of the absorption tower is generally more than 99%, and a ring-shaped flue gas "short circuit area" with a width of about 1.5 m is formed near the wall, in which the desulfurization efficiency can only reach about 90%. Calculation shows that about 90% of the SO2 escape occurs in this ring-shaped "short circuit area".

[0006] The traditional tray is designed with a fixed opening rate of about 35%, and the principle of tray efficiency determines that the selection of opening rate is a pair of contradictions between the increase of flue gas resistance and the increase of system efficiency, that is, the higher the opening rate, the lower the flue gas resistance, but the liquid holding layer is difficult to form, and the efficiency is weak; the lower the opening rate, the higher the flue gas resistance, but the liquid holding layer is thicker, and the efficiency is obvious.

[0007] In actual operation, the main problem faced by the fixed opening rate tray is the adaptability of working conditions, which is specifically manifested in that: the desulfurization tower is generally designed according to full load and high sulfur content, while the load of the power plant or the sulfur content of the coal fluctuates greatly and is lower than the design value in most cases, which leads to that the number of opened spray layers often cannot reach the design number. Since the tray is arranged below all the spray layers, the spray slurry acting on the tray is far less than the design condition, and since the opening rate of the tray is fixed, the slurry will directly pass through the hole and cannot form a certain thickness of the liquid holding layer on the tray. In this case, the desulfurization and dust removal effect of the tray is greatly reduced, and the existence of the tray resistance increases the system power consumption.

[0008] During low load operation, due to the reduction of flue gas volume, the flue gas flow rate also decreases significantly. Although the reduction of flow rate prolongs the residence time of flue gas in the absorption tower, research shows that the desulfurization reaction is more affected by the intensity of turbulent flow than the residence time. This directly affects the mass transfer efficiency between gas and liquid phases. Lower flow rate weakens the turbulent flow intensity of gas and liquid phases, reduces the mass transfer rate, and reduces the desulfurization efficiency.

[0009] Therefore, the current desulfurization efficiency increasing measures, such as the tray, the efficiency increasing ring and the like, are mostly designed as fixed structures without adjustment function. This limits their adaptability under different loads and different flue gas conditions, and it is difficult to effectively cope with the demand of deep load regulation and flexibility reconstruction of the thermal power generating unit. With the change of the power market, the frequent load change operation of the unit becomes the norm, and the fixed efficiency increasing measures have been difficult to meet the dynamically changing desulfurization demand, and it is urgent to develop more flexible and adjustable efficiency increasing technology. Practical new type content

[0010] Technical purpose: in view of the deficiency of the existing absorption tower for flue gas desulfurization treatment, the utility model discloses a kind of high-efficiency absorption tower of self-adapting load.

[0011] Technical scheme: to realize the above technical purpose, the utility model adopts the following technical scheme:

[0012] A kind of high-efficiency absorption tower of self-adapting load, including tower body, flue gas inlet and flue gas outlet are set on tower body, flue gas is from flue gas inlet into in tower body and flows from bottom to top to flue gas outlet, tower body forms slurry pool below flue gas inlet;On the flow path of flue gas, multiple porous trays, spray layer and demister are sequentially arranged along the flow direction, the edge wall cover plate that adjusts the flue gas flow area at porous tray along the circumferential direction with flue gas treatment load is arranged, the lower end of the edge wall cover plate is rotationally connected with the inner wall of tower body at the edge of porous tray, adjusting mechanism for adjusting the rotation angle of edge wall cover plate is arranged in tower body.

[0013] Preferably, the adjusting mechanism of the utility model includes adjusting connecting rod with the plate surface of edge wall cover plate abutting, and floating assembly connected with the lower end of adjusting connecting rod, the floating assembly is located in slurry pool area, and the buoyancy change generated by the liquid level rise of slurry pool is used to adjust the height direction of adjusting connecting rod.

[0014] Preferably, the plate surface of the edge wall cover plate of the utility model is provided with guide sliding groove matched with the end of adjusting connecting rod, and the end of adjusting connecting rod slides in guide sliding groove when adjusting connecting rod moves up and down to adjust the rotation angle of edge wall cover plate.

[0015] Preferably, the floating assembly of the utility model includes float and float limiting box, the float limiting box is fixedly installed in slurry pool and is communicated with slurry of slurry pool;The float is slidably arranged in the float limiting box, and the sliding direction is consistent with the lifting direction of adjusting connecting rod;The slide rail for guiding the sliding of float is correspondingly arranged in the float limiting box, and the horizontal movement of float is limited by the slide rail.

[0016] Preferably, the number of edge wall cover plates of the utility model is several groups, and they are evenly distributed along the circumferential direction of porous tray.

[0017] Beneficial effects: the utility model discloses a kind of high-efficiency absorption tower of self-adaptive load has following beneficial effects:

[0018] 1, the utility model discloses in porous tray is provided with side wall cover plate along circumferential direction, by changing the rotation angle of side wall cover plate, can adjust flue gas flow area, realize absorption tower with flue gas processing load self-adaptive change adjustment;Under low load operation, venturi effect can be formed, accelerate flue gas flow to improve gas-liquid mass transfer effect, along side wall upwards flue gas is simultaneously made by appropriate flow guiding to absorption tower center direction, avoid flue gas side wall escape effect, thereby improve desulfurization efficiency.

[0019] 2, the angle adjustment of the side wall cover plate of the utility model relies on adjusting connecting rod and floating assembly to realize, utilizes the liquid level height change of slurry pool caused by flue gas load change, realizes automatic adjustment, need not extra setting actuating mechanism and motor, simplify system control logic, reduce system failure rate.

[0020] 3, the utility model discloses by the rotation of side wall cover plate, open and close a part of tray opening, make the total opening rate of porous tray adjustable with load, ensure that when part of spray layer is closed and spray quantity is reduced under low load, the upper surface of porous tray still can form effective liquid holdup layer, thereby ensure the desulfurization and dust removal effect of tray under low load. DRAWINGS

[0021] In order to more clearly illustrate the technical scheme in the embodiment of the utility model or prior art, below will to the drawing used in embodiment or prior art description needed to make brief introduction.

[0022] Fig. 1 It is whole structural drawing for the utility model absorption tower;

[0023] Fig. 2 It is the cooperation schematic view of the side wall cover plate and porous tray in tower body for the utility model;

[0024] Fig. 3 It is the cooperation schematic view of floating body and floating body limiting box for the utility model;

[0025] Among them, 1-tower body, 2-flue gas inlet, 3-flue gas outlet, 4-slurry pool, 5-porous tray, 6-spray layer, 7-demister, 8-side wall cover plate, 9-adjusting connecting rod, 10-floating body, 11-floating body limiting box. DETAILED DESCRIPTION

[0026] Reference will now be made in detail to the embodiments of the present disclosure, one or more examples of which are set forth herein below. Each embodiment and example provides an explanation of devices, components, and materials of the present disclosure by way of illustration, and not limitation. Instead, the following description provides a convenient illustration for implementing exemplary embodiments of the present disclosure. Indeed, a person skilled in the art will readily appreciate that various modifications and variations can be made to the present disclosure without departing from the scope or spirit of the present disclosure.

[0027] As Figs. 1-3 shown, the utility model discloses a kind of self-adapting load's high-efficiency absorption tower, including tower body 1, flue gas inlet 2 and flue gas outlet 3 are arranged on tower body 1, flue gas enters in tower body from flue gas inlet 2 and flows from bottom to top to flue gas outlet 3, tower body 1 forms slurry pool 4 below flue gas inlet 2;On the flow path of flue gas, multiple porous trays 5, spray layer 6 and demister 7 are sequentially arranged along the flow direction, the edge wall cover plate 8 that flue gas flow area adjustment is carried out at porous tray 5 along circumferential direction is arranged, the lower end of the edge wall cover plate 8 is rotationally connected with the inner wall of tower body 1 at the edge of porous tray 5, adjusting mechanism for adjusting the rotation angle of edge wall cover plate is arranged in tower body 1.

[0028] As Fig. 2 shown, the number of the edge wall cover plate 8 of the utility model is several groups, preferably 8 groups, evenly distributed along the circumferential direction of porous tray 5, and the illustrated state is the state under low load condition, at this time, flow area reaches minimum, using this arrangement, when absorption tower low load operation, make flue gas concentrate in the central region of absorption tower, thereby avoiding flue gas edge wall escape effect;The variable cross-section flow structure formed by edge wall cover plate 8 forms Venturi effect, accelerates flue gas flow to improve gas-liquid mass transfer effect, to further improve desulfurization efficiency.

[0029] For the gap between edge wall cover plate 8 due to rotation, it can be considered to set elastic material between the edges of edge wall cover plate 8 or adopt similar folding plate structure such as folding fan, keep sealing between the edges of adjacent cover plates, so that flue gas flows out from the central passage, to further improve flue gas treatment effect.

[0030] The adjusting mechanism is used for driving the rotation of the rotating shaft which is in rotation cooperation with the edge wall cover plate 8, and is used for simplifying the equipment structure inside the absorption tower and realizing self-adaptive adjustment, and the adjusting mechanism comprises an adjusting connecting rod 9 which is in abutment with the plate surface of the edge wall cover plate 8 at the upper end and a floating assembly which is connected with the lower end of the adjusting connecting rod 9, the floating assembly is located in the slurry pool 4 area, and the height direction of the adjusting connecting rod 9 is adjusted by using the buoyancy change caused by the liquid level rising and falling of the slurry pool 4; in actual operation, the liquid level of the absorption tower needs to be adjusted along with the load (the size of the tower flue gas amount of reaction). When the load is increased, the liquid level is increased, and vice versa. When the system is in high load operation, the tower flue gas amount is increased, and the slurry pool liquid level is also in high position operation; therefore, the edge wall cover plate 8 can be rotationally adjusted based on the high position change of the floating assembly caused by the change of the liquid level, the adjusting connecting rod 9 is used for ensuring sufficient supporting force to push the edge wall baffle to rotate, and preferably, a rigid rod is adopted, and the rod body passes through the multi-hole tray 5 and is matched with the plate surface of the edge wall cover plate 8.

[0031] The plate surface of the edge wall cover plate 8 is provided with a guide sliding groove matched with the end portion of the adjusting connecting rod 9, when the adjusting connecting rod 9 is moved up and down to adjust the rotation angle of the edge wall cover plate 8, the end portion of the adjusting connecting rod 9 slides in the guide sliding groove, and when the adjusting connecting rod 9 is lowered, the edge wall cover plate 8 is rotated downward under the action of gravity.

[0032] Meanwhile, considering that the slurry pool has relatively strong disturbance when the absorption tower is operated, if the floating assembly lacks fixation, horizontal vibration will be caused due to the disturbance, therefore, the floating assembly of the utility model comprises a float 10 and a float limiting box 11, the float limiting box 11 is fixedly installed in the slurry pool 4 and is in communication with the slurry of the slurry pool 4; the float 10 is slidably arranged in the float limiting box 11, and the sliding direction is consistent with the lifting direction of the adjusting connecting rod 9; the sliding rails for guiding the sliding of the float 10 are correspondingly arranged in the float limiting box 11, the horizontal movement of the float 10 is limited through the sliding rails, the float is allowed to move in the up-down direction, so that the effect of pushing the edge wall cover plate through the connecting rod can be ensured when the liquid level changes.

[0033] The utility model discloses a kind of high-efficiency absorption tower of self-adaptive load, when using, flue gas enters from flue gas import 2, in turn flow through porous tray 5, spray layer 6 and demister 7, finally discharge from flue gas export, spray layer 6 is equipped with several groups atomizing nozzle, slurry in slurry pool is transported to nozzle by pump and pipeline to spray treatment to flue gas;In high load condition, the liquid level in slurry pool 4 also keep in high liquid level condition, so that side wall cover plate 8 rotates upward and opens, flue gas increases in this place The flow area, absorption zone in absorption tower can keep normal flue gas flow rate and tray opening rate at this time;In low load state, slurry liquid level height in slurry pool 4 reduces, side wall cover plate 8 rotates downward, flue gas reduces in porous tray 5 The flow area, one is that flue gas can form a venturi effect at this place, accelerate flue gas flow to improve gas-liquid mass transfer effect;Two is to make flue gas guide to tower center direction, avoid side wall escape phenomenon, increase desulfurization effect;Three is that side wall cover plate seals a part of tray opening, so that the total opening rate of tray drops, when spray amount reduces under low load, the upper surface of porous tray still can form effective liquid holdup layer, to improve flue gas processing effect under low load;The adjusting mode of the utility model can automatically adjust absorption tower according to flue gas processing load without additional setting actuating mechanism and motor.

Claims

1. A self-adapting load efficient absorption column, characterized in that, The application relates to a tower body (1), a flue gas inlet (2) and a flue gas outlet (3) are arranged on the tower body (1), flue gas enters the tower body from the flue gas inlet (2) and flows upwards to the flue gas outlet (3), the tower body (1) forms a slurry pool (4) below the flue gas inlet (2); a porous tray (5), a spraying layer (6) and a demister (7) are arranged in sequence along the flow direction on the flow path of the flue gas, edge wall cover plates (8) for adjusting the flue gas flow area at the porous tray (5) according to the treatment load of the flue gas are arranged in the circumferential direction of the porous tray (5), the lower end of the edge wall cover plate (8) is rotationally connected with the inner wall of the tower body (1) at the edge of the porous tray (5), and an adjusting mechanism for adjusting the rotation angle of the edge wall cover plate is arranged in the tower body (1).

2. An adaptive load high efficiency absorption tower according to claim 1, characterized in that, The adjusting mechanism comprises an adjusting connecting rod (9) abutting against the plate surface of the edge wall cover plate (8) at the upper end and a floating assembly connected with the lower end of the adjusting connecting rod (9), the floating assembly is located in the slurry pool (4) area, and the height direction of the adjusting connecting rod (9) is adjusted by using the buoyancy change generated by the liquid level rising of the slurry pool (4).

3. An adaptive load high efficiency absorption tower according to claim 2, characterized in that, A guide sliding groove matched with the end of the adjusting connecting rod (9) is arranged on the plate surface of the edge wall cover plate (8), and the end of the adjusting connecting rod (9) slides in the guide sliding groove when the adjusting connecting rod (9) moves up and down to adjust the rotation angle of the edge wall cover plate (8).

4. An adaptive load high efficiency absorption tower according to claim 2, wherein, The floating assembly comprises a floating body (10) and a floating body limiting box (11), the floating body limiting box (11) is fixedly installed in the slurry pool (4) and communicates with the slurry of the slurry pool (4); the floating body (10) is slidably arranged in the floating body limiting box (11), the sliding direction of the floating body (10) is consistent with the lifting direction of the adjusting connecting rod (9); a sliding rail for guiding the sliding of the floating body (10) is arranged in the floating body limiting box (11), and the horizontal movement of the floating body (10) is limited through the sliding rail.

5. An adaptive load high efficiency absorption tower as claimed in claim 1, wherein, The number of the edge wall cover plates (8) is several groups, and the edge wall cover plates (8) are uniformly distributed along the circumferential direction of the porous tray (5).

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