CN111729504A - A composite adsorption reaction device coupled with a fluidized bed and a moving bed and its application - Google Patents

Abstract

The invention relates to a composite adsorption reaction device coupled with a fluidized bed and a moving bed and its application, comprising an adsorption device main body (1) and an intake fume box (14) located at the bottom of the adsorption device main body (1). The main body (1) is provided with a fluidized bed and a moving bed, and the fluidized bed includes a Venturi accelerator tube (11) and a fluidized bed body, and the Venturi accelerator tube (11) is located in the intake fume box (14). ) and the fluidized bed, and communicate with the powder adsorbent Venturi jetting device (12), the moving bed includes a conical support sieve plate and a particulate adsorbent moving bed, and the particulate adsorbent moving bed is installed On the conical supporting sieve plate, the conical supporting sieve plate is connected to the particle adsorbent conveying device (13) through the guide pipe (10). Compared with the prior art, the present invention can significantly improve the utilization efficiency of the adsorbent and the removal efficiency of gaseous pollutants such as SO ₃ , and also has the function of dust removal, and can effectively remove gaseous pollutants such as SO ₃ in the flue gas.

Description

A composite adsorption reaction device coupled with a fluidized bed and a moving bed and its application

technical field

The invention belongs to the adsorption and removal technology of flue gas gaseous pollutants in the field of environmental protection, and particularly relates to a composite adsorption reaction device coupled with a fluidized bed and a moving bed and its application.

Background technique

my country's heavy non-ferrous metal smelting output has ranked first in the world for more than ten consecutive years. However, in the smelting process of heavy non-ferrous metals such as lead, zinc, copper, etc., since the raw materials are mainly sulfides, the smelting flue gas contains high concentrations of sulfur oxides. In the purification process of non-ferrous metal smelting flue gas, washing is generally used to cool down, and the high concentration of SO ₃ in flue gas is the main reason for the generation of foul acid in smelting flue gas washing. The control of washing pollution has also become the focus and difficulty of pollution prevention and control in the non-ferrous metal smelting industry. Therefore, the use of adsorbents to effectively capture SO ₃ in flue gas before scrubbing, and the efficient removal of adsorbents by dust removal devices will significantly reduce the amount of scrubbing acid generated. Before non-ferrous metal smelting flue gas washing, there is generally only dust removal equipment, among which the electrostatic dust removal device cannot effectively remove SO ₃ , and SO ₃ is easy to condense during the cooling process, so it will cause adverse effects on corrosion and blockage of the bag type dust removal device. It is difficult to use the conventional electrostatic precipitator or the bag filter to give full play to the capture effect of the adsorbent on gaseous pollutants such as SO ₃ . Therefore, it is urgent to develop a dry capture equipment that can efficiently remove gaseous pollutants such as _SO3 .

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an efficient composite adsorption reaction device coupled with a fluidized bed and a moving bed and its application in order to overcome the above-mentioned defects of the prior art.

The object of the present invention can be achieved by the following technical solutions: a composite adsorption reaction device coupled with a fluidized bed and a moving bed, characterized in that it includes an adsorption device main body and an air intake smoke box located at the bottom of the adsorption device main body. The main body of the adsorption device is provided with a fluidized bed and a moving bed. The fluidized bed includes a Venturi accelerator tube and a fluidized bed bed. The Venturi accelerator tube is located between the intake fume box and the fluidized bed bed. and communicated with the powder adsorbent venturi jetting device, the moving bed includes a conical support sieve plate and a particle adsorbent moving bed, the particulate adsorbent moving bed is installed on the conical support sieve plate, and the conical support sieve plate The supporting sieve plate is connected to the particle adsorbent conveying device through the guide pipe.

The powder adsorbent venturi spraying device sprays the powder adsorbent into the flue, and adsorbs the gaseous pollutants in the fluidized bed.

The particle size of the powder adsorbent is 100-325 mesh (0.150-0.045mm in diameter), which can have a high adsorption capacity for gaseous pollutants. Powder adsorbents can be common alkaline adsorbents such as sodium carbonate, sodium bicarbonate, magnesium carbonate, magnesium oxide, calcium carbonate, calcium oxide, etc. The adsorbent with this particle size has a larger specific surface area, faster absorption, and is also easy to flow. change.

The inclination angle between the conical support sieve plate and the horizontal direction is 30-60 degrees, which is convenient for particle adsorption to move downward at a stable speed. And granular adsorbent, and ensure that the granular adsorbent will not fall off the sieve plate; the opening rate is 20-60%, which can allow the flue gas to easily penetrate the sieve plate, and its size can be adjusted according to the resistance loss.

The conical support sieve plate includes an upper conical plate and a lower conical plate, the openings of the upper and lower conical plates are butted together, the particle adsorbent conveying device is connected to the cone bottom of the upper conical plate, and the cone of the lower conical plate is The bottom is connected to the guide pipe, and the particle adsorbent conveying device conveys the particle adsorbent to the upper cone plate.

The granular adsorbent moving bed includes multi-layer beds arranged in parallel up and down, each layer of the bed is fixed on the conical support sieve plate, and a height-limiting ring is arranged on each bed, and the granular adsorbent is from top to bottom. With the conical support sieve plate moving downward, the thickness of the falling particle adsorbent moving bed is maintained at 20-50mm under the action of the height-limiting ring. The height-limiting ring is welded on the conical support plate through 4-6 supporting baffles. The height of these supporting baffles is 20-50mm, and its direction is consistent with the radial direction of the conical plate, so as to ensure that the particles flow from the top to the top. In the process of moving down, the support baffles are evenly distributed on the conical support plate to avoid the situation that there are many particulate adsorbents in some places and no particulate adsorbents in some places.

The particulate adsorbent is drawn out from the moving bed of the particulate adsorbent through a guide tube, the angle between the guide tube and the horizontal direction is 60-80 degrees, and the particulate adsorbent is an adsorbent with a diameter of 5-8 mm. The particulate adsorbent can be sodium carbonate, sodium bicarbonate, magnesium carbonate, magnesium oxide, calcium carbonate, calcium oxide and other common alkaline absorbents. The adsorbent with this particle size has large particles and is easy to go from top to bottom on the conical plate. move.

A method for purifying flue gas using the compound adsorption reaction device coupled with the fluidized bed and the moving bed, comprising the following steps:

In the first step, the powder adsorbent is sprayed into the flue, and enters the fluidized bed from the intake smoke box. The flue gas is first accelerated by the Venturi accelerator and enters the fluidized bed bed. The powder adsorbent forms an efficient gas-solid fluidized state contact. During the rising process, part of the material returns downward to form an internal circulating particle flow, which strengthens the gas-solid mass transfer and heat transfer, and achieves efficient removal of gaseous pollutants and adsorption saturation. The powder adsorbent is discharged from the bottom of the intake fume box;

In the second step, the flue gas passes through the particle adsorbent moving bed on the conical support screen, and the gaseous pollutants are further adsorbed by the particulate adsorbent, and the powder adsorbent carried by the flue gas is also intercepted by the particulate adsorbent moving bed. down to further adsorb gaseous pollutants;

In the third step, the particulate adsorbent moving from top to bottom flows out along the guide pipe, and returns from the top of the conical support sieve plate through the particulate adsorbent conveying device to perform cyclic adsorption treatment on the flue gas pollutants;

In the fourth step, the flue gas after the double adsorption of the fluidized bed and the moving bed is dedusted by the cyclone separation plate, and then passed into the subsequent flue gas purification device through the induced draft fan.

The temperature of the flue gas is 150-450°C.

The flow velocity of the flue gas in the fluidized bed is 4-10m/s, and the flow velocity of the flue gas at the venturi accelerating tube is 15-25m/s.

In the present invention, the powder adsorbent is first sprayed into the flue, and the flue gas carries the powder adsorbent from the smoke box at the bottom _of the reaction tower into the reaction tower; fluidized adsorbent particles and gaseous pollutants such as SO3 in the flue gas flow in the reaction tower. A chemical reaction takes place in the gasification section; then the particle adsorbent layer moving on the conical support sieve plate continues to further adsorb the residual SO ₃ and other gaseous pollutants in the flue gas passing through the sieve plate while acting as a filter bed; The flue gas after adsorption and filtration of the moving bed is discharged from the top, and the fine dust can be removed by the cyclone separation device before entering the subsequent purification process. The present invention firstly utilizes the powder adsorbent for preliminary adsorption _of SO3 and other gaseous pollutants in a fluidized state, and then utilizes the granular adsorbent for deep adsorption _of SO3 and other gaseous pollutants in a mobile state. In addition to adsorbing gaseous pollutants such as SO ₃ in the flue gas, the moving bed adsorbent can also intercept the powder adsorbent carried by the flue gas and continue to adsorb gaseous pollutants such as SO ₃ in the flue gas. At the same time, the particulate adsorbent can also flow out of the adsorption tower through the guide pipe (10), and be transported to the top of the moving bed through the adsorbent conveying device (13) for circulating adsorption. The invention can significantly improve the utilization efficiency of the adsorbent and the removal efficiency of gaseous pollutants such as SO ₃ , and has the function of dust removal at the same time, and can effectively remove gaseous pollutants such as SO ₃ in the flue gas.

Compared with the prior art, the present invention has the following advantages:

1. The present invention effectively combines the fluidized bed and the moving bed, which not only utilizes the powder adsorbent in the fluidized bed to efficiently adsorb the gaseous pollutants, but also utilizes the particulate adsorbent in the moving bed to deeply adsorb the gaseous pollutants. The removal of gaseous pollutants improves the removal efficiency of gaseous pollutants; the use of fluidized bed adsorption unit requires the use of powder adsorbents to achieve its fluidized state, and its specific surface area is large, the adsorption speed is fast, and the adsorption efficiency is high, so the fluidized adsorption The unit is arranged in the lower part to adsorb pollutants as much as possible; while the granular adsorbent is arranged in the upper part, it can not only capture and recycle the powder adsorbent by its filtering and dust removal effect, but also use its own characteristics to further adsorb the pollutants in the flue gas to achieve deep Removal; both adsorbents can be recovered and recycled, which improves the use efficiency of the adsorbents.

2. The powder adsorbent of the present invention is carried into the moving bed by the flue gas, intercepted by the particulate adsorbent in the moving bed, and continues to adsorb gaseous pollutants together with the particulate adsorbent in the moving bed, improving the powder adsorption. It can improve the utilization efficiency of the agent, and also play the role of preliminary dust removal;

3. The particulate adsorbent used in the present invention is drawn out of the adsorption tower through the guide pipe, and is re-inputted to the top of the adsorption tower through the particulate adsorbent conveying device, which can adsorb the flue gas pollutants cyclically and improve the utilization efficiency of the particulate adsorbent.

4. The present invention is suitable for dry capture and purification of gaseous pollutants in various industrial flue gases such as coal burning, industrial boilers, metal smelting, cement production, petrochemical industry, and waste incineration.

Description of drawings

FIG. 1 is a schematic structural diagram of a composite adsorption reaction device in which a fluidized bed and a moving bed are coupled according to the present invention.

Detailed ways

The present invention will be described in detail below with reference to the specific drawings and embodiments. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

As shown in FIG. 1, a composite adsorption reaction device with a fluidized bed coupled with a moving bed includes an adsorption device main body 1 and an intake fume box 14 located at the bottom of the adsorption device main body 1. The adsorption device main body 1 is provided with Fluidized bed and moving bed, the fluidized bed includes a Venturi accelerator tube 11 and a fluidized bed bed, the Venturi accelerator tube 11 is located between the intake fume box 14 and the fluidized bed bed, and communicates with the powder Adsorbent venturi injection device 12, the moving bed includes a conical support sieve plate and a particle adsorbent moving bed, the particulate adsorbent moving bed is installed on the conical support sieve plate, and the conical support sieve The plate is connected to the particulate sorbent delivery device 13 through the draft tube 10 . The conical support sieve plate includes an upper conical plate 6 and a lower conical plate 9, the openings of the upper conical plate 6 and the lower conical plate 9 are butted, and the particle adsorbent conveying device 13 is connected to the cone bottom of the upper conical plate 6. , the conical bottom of the lower conical plate 9 is connected to the guide pipe 10 , and the particle adsorbent conveying device 13 conveys the particulate adsorbent to the upper conical plate 6 . The granular adsorbent moving bed includes multi-layer beds arranged in parallel up and down, each layer of the bed is fixed on the conical support sieve plate, and a height-limiting ring is arranged on each bed, and the granular adsorbent is from top to bottom. With the conical support sieve plate moving downward, the thickness of the falling particle adsorbent moving bed is maintained at 20-50mm under the action of the height-limiting ring.

The inclination angle between the conical support sieve plate and the horizontal direction is 30-60 degrees, the size of the sieve holes is 2-3 mm, and the opening rate is 20-60%. The lower conical plate 9 is led out of the adsorption tower through a guide pipe 10 with a diameter of 100mm. The angle between the guide pipe and the horizontal direction is 60-80 degrees. movement. The powder adsorbent and granular adsorbent used are one of alkaline adsorbents such as sodium hydroxide, sodium oxide, sodium carbonate, sodium bicarbonate, magnesium hydroxide, magnesium oxide, magnesium carbonate, calcium hydroxide, calcium oxide, calcium carbonate and the like. one or more combinations. The particle size of the powder adsorbent is 100-325 mesh (0.150-0.045mm in diameter), the particle size of the adsorbent is about 5-8mm in diameter, and the temperature of the flue gas is 150-450°C. The flow velocity of the flue gas in the fluidized bed is 4-10m/s, and the flow velocity of the flue gas at the venturi accelerating tube is 15-25m/s.

Example 1

The present invention utilizes a compound adsorption reaction device in the laboratory which is coupled with a fluidized bed and a moving bed to conduct experimental research. The simulated non-ferrous metal smelting flue gas is provided by calcining lead sulfide ore powder in a rotary kiln, and the flue gas volume is 100Nm ³ /h. After the flue gas at the outlet of the rotary kiln passes through the cooling device, it is passed into the above-mentioned composite adsorption reaction device coupled with the fluidized bed and the moving bed, and finally the flue gas is passed through the induced draft fan to the subsequent flue gas deep evolution equipment. The temperature of the flue gas at the outlet of the cooling device downstream of the rotary kiln is kept at 200°C, the concentration of SO ₃ is 1000mg/Nm ³ , the concentration of dust is 1g/Nm ³ , and the airflow velocity of the flue gas in the fluidization section is 5m/s, The filtration speed in the moving bed was 1 m/min. The moving speed of the particulate adsorbent in the moving bed is 5 mm/s, and the concentration of the powder adsorbent in the flue gas is 100-300 mg/m ³ .

Example 2

The experiment was carried out using the same compound adsorption reaction device coupled with the fluidized bed and the moving bed as in Example 1. The concentration of SO ₃ in the flue gas was 1000 mg/Nm ³ , and a certain amount of powder adsorbent (sodium bicarbonate) was sprayed into the pipeline. ), the concentration of the powder adsorbent in the flue gas is 100 mg/m ³ . Activated alumina pellets (3 mm in diameter) were selected as the particulate adsorbent, and the moving speed of the particulate adsorbent in the moving bed was 5 mm/s. The velocity of the flue gas in the fluidization section is 5m/s, and the filtration velocity of the moving bed is 1m/min. After passing through the composite adsorption reaction device of the present invention coupled with the fluidized bed and the moving bed, the dust concentration of the flue gas is 0.05g/Nm ³ , the SO ₃ concentration is 200 mg/Nm ³ , and the SO ₃ removal efficiency is about 80%.

Example 3

The experiment was carried out using the same compound adsorption reaction device coupled with the fluidized bed and the moving bed as in Example 1. The concentration of SO ₃ in the flue gas was 1000 mg/Nm ³ , and a certain amount of powder adsorbent (sodium bicarbonate) was sprayed into the pipeline. ), the concentration of the powder adsorbent in the flue gas is 200 mg/m ³ . Activated alumina pellets (3 mm in diameter) were selected as the particulate adsorbent, and the moving speed of the particulate adsorbent in the moving bed was 5 mm/s. The velocity of the flue gas in the fluidization section is 5m/s, and the filtration velocity of the moving bed is 1m/min. After passing through the composite adsorption reaction device of the present invention coupled with the fluidized bed and the moving bed, the dust concentration of the flue gas is 0.05g/Nm ³ , the SO ₃ concentration is 80 mg/Nm ³ , and the SO ₃ removal efficiency is about 92%.

Claims (10)

1. A composite adsorption reaction device coupled with a fluidized bed and a moving bed, characterized in that it comprises an adsorption device main body (1) and an air intake fume box (14) located at the bottom of the adsorption device main body (1), the adsorption The device main body (1) is provided with a fluidized bed and a moving bed, and the fluidized bed includes a Venturi accelerator tube (11) and a fluidized bed body, and the Venturi accelerator tube (11) is located in the intake fume box (11). 14) and the fluidized bed, and communicate with the powder adsorbent Venturi jetting device (12), the moving bed comprises a conical support sieve plate and a particulate adsorbent moving bed, and the particulate adsorbent moving bed It is installed on the conical supporting sieve plate, and the conical supporting sieve plate is connected to the particle adsorbent conveying device (13) through the guide pipe (10). 2. The composite adsorption reaction device coupled with a fluidized bed and a moving bed according to claim 1, characterized in that, the Venturi injector (12) injects the powder adsorbent into the flue, and in the flow The chemical bed adsorbs gaseous pollutants. 3. A compound adsorption reaction device with a fluidized bed and a moving bed coupled according to claim 2, wherein the particle size of the powder adsorbent is 100-325 mesh, which can have relatively high resistance to gaseous pollutants. High adsorption capacity. 4. The composite adsorption reaction device with a fluidized bed and a moving bed coupled according to claim 1, wherein the inclination angle between the conical support sieve plate and the horizontal direction is 30-60 degrees, and the sieve hole is 30-60 degrees. The size is 2-3mm, and the opening rate is 20-60%. 5. The composite adsorption reaction device with a fluidized bed coupled with a moving bed according to claim 1, wherein the conical support sieve plate comprises an upper conical plate (6) and a lower conical plate (9) , the openings of the upper cone plate (6) and the lower cone plate (9) are butted together, and the particle adsorbent conveying device (13) is connected to the cone bottom of the upper cone plate (6) and the cone bottom of the lower cone plate (9). The guide pipe (10) is connected, and the particulate adsorbent conveying device (13) conveys the particulate adsorbent to the upper cone plate (6). 6 . The composite adsorption reaction device with a fluidized bed coupled with a moving bed according to claim 5 , wherein the particle adsorbent moving bed comprises a multi-layer bed body arranged in parallel up and down, and each layer bed body It is fixed on the conical support sieve plate, and each bed is provided with a height limit ring. The particulate adsorbent moves down along the conical support sieve plate from top to bottom, and the thickness of the moving bed of the particulate adsorbent is within the height limit. Under the action of the ring, it is kept at 20-50mm. 7. A composite adsorption reaction device with a fluidized bed coupled with a moving bed according to claim 6, characterized in that the particulate adsorbent is drawn out from the particulate adsorbent moving bed through a guide pipe (10), and the particulate adsorbent is guided out of the moving bed. The angle between the flow pipe (10) and the horizontal direction is 60-80 degrees, and the particle adsorbent is an adsorbent with a diameter of 5-8 mm. 8. A method for purifying flue gas using the composite adsorption reaction device coupled with a fluidized bed and a moving bed according to any one of claims 1 to 7, characterized in that, comprising the following steps: In the first step, the powder adsorbent is sprayed into the flue, and enters the fluidized bed from the intake smoke box (14). The powder adsorbent in the fluidized bed forms an efficient gas-solid fluidized contact. During the rising process, part of the material returns downward to form an internal circulating particle flow, which strengthens the gas-solid mass transfer and heat transfer to achieve high-efficiency removal. For gaseous pollutants, the saturated powder adsorbent is discharged from the bottom of the intake fume box (14); In the second step, the flue gas passes through the particle adsorbent moving bed on the conical support screen, and the gaseous pollutants are further adsorbed by the particulate adsorbent, and the powder adsorbent carried by the flue gas is also intercepted by the particulate adsorbent moving bed. down to further adsorb gaseous pollutants; In the third step, the particulate adsorbent moving from top to bottom flows out along the guide pipe (10), and returns from the top of the conical support sieve plate through the particulate adsorbent conveying device (13) to carry out cyclic adsorption of flue gas pollutants deal with; In the fourth step, the flue gas after the double adsorption of the fluidized bed and the moving bed is dedusted by the cyclone separation plate, and then passed into the subsequent flue gas purification device through the induced draft fan. 9 . The method for purifying flue gas using a composite adsorption reaction device coupled with a fluidized bed and a moving bed according to claim 8 , wherein the temperature of the flue gas is 150-450° C. 10 . 10. The method for purifying flue gas using the composite adsorption reaction device coupled with a fluidized bed and a moving bed according to claim 8, wherein the gas flow rate of the flue gas in the fluidized bed is 4- 10m/s, the flue gas flow velocity at the Venturi accelerator tube (11) is 15-25m/s.

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