CN207042240U - A kind of calcium base circulating ash high solid-gas ratio cyclone desulfuration equipment - Google Patents

Abstract

The utility model discloses a calcium-based circulating ash high-solid-gas ratio swirl desulfurization equipment, which includes a high-solid-gas ratio swirl desulfurization tower, a bag-type dust collector, a digester, a humidification pool, etc.; The digested slaked lime is mixed with the desulfurization ash collected by the bag filter into the humidification tank, and water is added to form the humidification ash, which is powered by the fluidization wind and enters the high solid-gas ratio cyclone desulfurization tower with the help of the negative pressure of the flue. The sulfur flue gas and the humidification ash in the tower rotate and shear turbulent movement around the center stabilizing rod. During the movement, the ideal desulfurization reaction humidity and temperature conditions are gradually formed, and the desulfurization process is finally completed. The unreacted coarse particles are humidified The ash enters the tower again through the separation device for reaction; the utility model is suitable for the flue gas desulfurization of various industrial kilns, and has the advantages of high desulfurization efficiency, high utilization rate of desulfurizer, no sticking wall phenomenon, zero waste water, investment cost and operation Features such as low cost.

Description

A calcium-based circulating ash high solid-gas ratio cyclone desulfurization equipment

technical field

The utility model belongs to the technical field of flue gas desulfurization of industrial kilns, in particular to a calcium-based circulating ash high-solid-gas ratio cyclone desulfurization equipment.

Background technique

In recent years, my country has continuously increased the control of industrial air pollutants, and implemented the policy of combining the total amount control of air pollutants and the control of emission concentration. Especially in the field of flue gas desulfurization, more stringent air pollutant emission standards have been implemented. According to the "Coal Power Energy Conservation and Emission Reduction Upgrading Action Plan" jointly issued by the National Development and Reform Commission, the Ministry of Environmental Protection and the National Energy Administration in July 2014, it is clearly required that the emission concentration of air pollutants from newly built coal-fired power generation units in 11 eastern provinces and cities should basically reach that of gas turbine units. The emission limit value is "50355", and the newly built units in 8 provinces and cities in the central region (including Shanxi) are close to or reach the ultra-clean emission limit in principle, and the western regions are encouraged to approach or reach the ultra-clean emission limit. This means that the future concentration of sulfur dioxide emissions from coal-fired power plants needs to reach the concentration limit of 35mg/Nm ³ .

The mainstream flue gas desulfurization technology of industrial furnaces can be divided into desulfurization before combustion, desulfurization during combustion and desulfurization after combustion. Among them, post-combustion desulfurization is the control method with the most mature technology, the most widely used and the highest desulfurization efficiency. According to the physical characteristics of desulfurization agent and desulfurization by-products, desulfurization after combustion can be divided into: wet desulfurization, semi-dry desulfurization and dry desulfurization. Among them, semi-dry desulfurization not only has the advantages of fast reaction speed and high desulfurization efficiency of wet desulfurization, but also has the advantages of zero waste water discharge and easy disposal of desulfurized products after dry desulfurization.

The technological process of humidified ash circulation desulfurization technology (NID technology) is that the flue gas to be treated enters the reactor through the bottom of the reactor, and reacts with the absorbent evenly mixed in the humidified circulating ash. Under the condition of cooling and humidification, the SO2 in the flue gas reacts with the absorbent to generate calcium sulfite and calcium _sulfate . The flue gas after the reaction carries a large amount of dry solid particles into the dust collector after desulfurization for collection and purification. After being collected by the dust collector after desulfurization, the dry circulating ash is separated from the flue gas by the dust collector, and then sent to the mixer by the conveying equipment. cycle again. The purified flue gas is about 15°C higher than the dew point temperature, without reheating, and is discharged into the chimney through the induced draft fan.

However, this kind of technical process and desulfurization reaction process has the following disadvantages:

1. The existing NID semi-dry desulfurization technology usually needs to add a first-stage electrostatic precipitator in front of the reactor to pre-collect the dust particles in the flue gas in order to create a better working environment for the desulfurization reactor, but it increases System resistance, which reduces the system operating rate.

2. In semi-dry desulfurization, when the temperature and humidity both reach the ideal desulfurization conditions, it is necessary to ensure the residence time of the desulfurizer in the flue gas to improve the desulfurization efficiency and the utilization rate of the desulfurizer. The reactor of the existing NID semi-dry desulfurization technology is a transport bed rectangular reactor. To ensure the residence time of the desulfurizer in the flue gas, the height of the reactor can only be increased by exchanging space for time.

3. In the existing NID semi-dry desulfurization technology, the shear force of the flow field in the reactor is small, the turbulence intensity is not high, and the gas-solid mixing is insufficient, which directly affects the speed and efficiency of the desulfurization reaction.

4. In the existing NID semi-dry desulfurization technology, the flue gas after the desulfurization reaction carries a large amount of desulfurization ash particles into the dust collector, and the dry desulfurization ash is separated from the flue gas by the dust collector, and is transported to the mixer by the conveying equipment. Since the NID technology itself has no internal circulation, almost all circulating desulfurization ash is collected by the bag filter, which undoubtedly increases the working pressure of the bag filter and shortens the replacement time of the filter bag.

Contents of the invention

In order to overcome the shortcomings of the above-mentioned prior art, the purpose of this utility model is to provide a calcium-based circulating ash high solid-gas ratio cyclone desulfurization equipment, which can make the sulfur-containing flue gas and desulfurizer rotate and shear turbulent flow along the central axis of the reactor Movement, and prolong the residence time of the desulfurizer in the flue gas, increase the contact area of the gas-solid two-phase, make the desulfurization reaction more complete, reduce the system resistance, and improve the system operation rate.

In order to achieve the above object, the technical solution adopted by the utility model is:

A calcium-based circulating ash high solid-gas ratio swirl desulfurization, comprising a high solid-gas ratio swirl desulfurization tower 1, characterized in that the high solid-gas ratio swirl desulfurization tower 1 includes a main tower 2 and an auxiliary tower with a closed top 3. The upper part of the main tower 2 is a cylindrical cylinder structure, and the lower part is a conical structure. The attached tower 3 is a cylindrical cylinder structure. The top is connected with the main tower 2 through a horizontal channel, and the bottom is connected with the bag filter 7. Vertical center stabilizing rods 6 for stabilizing the rotating shear turbulent flow field are respectively arranged at the center of the cross sections of the main tower 2 and the auxiliary tower 3 .

The lower part of the attached tower 3 is bent into a horizontal shape, and a coarse particle separation device 4 with a discharge lock valve 5 is arranged below the bending position. The coarse particle separation device 4 is a conical structure for separating The incompletely reacted coarse-grained calcium-based circulating ash is returned to the lower part of the cylindrical shell structure of the main tower 2.

The tangential air inlet structure of the main tower 2 is a rectangular pipe, rhombic pipe or circular pipe, and the tangential air inlet structure of the auxiliary tower 3 is a rectangular pipe, rhombic pipe or circular pipe.

The tangential air inlet structure of the main tower 2 cuts into or directly cuts into the barrel volute of the main tower 2, and the tangential air inlet structure of the attached tower 3 cuts into or cuts directly into the barrel volute of the attached tower 3.

The bag filter 7 receives the flue gas and desulfurization ash from the attached tower 3 for flue gas dust removal and desulfurization ash capture. The bottom of the bag filter 7 is arranged with a screw feeder 8 to send the captured desulfurization ash to to the desulfurization ash bin 9 for storage.

The lower part of the desulfurization ash bin 9 is provided with a gate valve 10 for connecting or cutting off the desulfurization ash supply path, and the lower part of the gate valve 10 is arranged with a three-way distributing valve 11 for realizing the external discharge and supply of the desulfurization ash. One side of the material valve 11 is connected to the air conveying chute 12 for sending the desulfurized ash to the humidification tank 16, and the lower part of the quicklime bin 13 is connected by a belt conveyor 14 to send the quicklime particles into the digestion tank 15 for digestion , the digested slaked lime particles are sent to the humidification tank 16, uniformly mixed with desulfurization ash and finally added with water to form calcium-based circulating ash.

The utility model also provides a calcium-based circulating ash high solid-gas ratio swirl desulfurization method, the high solid-gas ratio swirl desulfurization tower 1 is set as the main tower 2 and the attached tower 3 side by side, and the main tower 2 and the attached tower 3 The center vertical center flow stabilizing rod 6, the main tower 2 and the auxiliary tower 3 are connected through a horizontal passage at the top, the upper part of the main tower 2 is cylindrical, and the lower part is conical, and the sulfur-containing flue gas flows from the lower part of the main tower 2 cylindrical structure. Tangential entry, in the main tower 2 and the calcium-based circulating ash around the center stabilizing rod 6 to make an upward rotational shear turbulent movement until the top of the main tower 2, and then enter the auxiliary tower 3 tangentially, continue in the auxiliary tower 3 Calcium-based circulating ash revolves around the center stabilizing rod 6 and performs downward rotary shear turbulent movement until the coarse particle separation device 4. The incompletely reacted coarse-grained calcium-based circulating ash enters the main tower 2 again through the separation device for reaction, and the fine particles The desulfurized ash enters the bag filter 7 for collection along with the desulfurized flue gas.

The desulfurization ash collected by the bag filter 7 is partly discharged and supplied, and the other part is sent to the humidification tank 16 to form new calcium-based circulating ash with digested slaked lime particles, which is sent back to the main tower 2 for use. The moisture content of the circulating ash is about 5%, and the circulation ratio is in the range of 30-150.

During the process of the sulfur-containing flue gas and calcium-based circulating ash rotating and shearing turbulent movement around the center stabilizing rod 6, the temperature of the flue gas decreases from 140-180°C to 70-80°C, and the relative humidity of the flue gas increases to 40-80°C. 50%.

The tangential wind speed of the main tower 2 is in the range of 15-25 m/s, and the tangential wind speed of the auxiliary tower 3 is in the range of 10-20 m/s.

Compared with the prior art, the beneficial effects of the utility model are:

1) In this utility model, the high-solid-gas ratio swirl desulfurization tower is divided into two stages, that is, the main tower and the auxiliary tower. The pre-collection of dust particles in the flue gas can cancel the dust removal unit added in front of the reactor of the existing NID semi-dry desulfurization technology, thereby reducing resistance and improving system operation rate.

2) In the utility model, the sulfur-containing flue gas and the desulfurizing agent perform rotational shear turbulent movement along the central axis of the main tower and the auxiliary tower, which greatly prolongs the residence time of the desulfurizing agent in the flue gas, so the height of the reactor can be greatly reduced , and improve desulfurization efficiency and desulfurization agent utilization.

3) In the utility model, a strong shear flow field is formed in the reactor, and the swirl turbulence intensity is extremely high, and a central stabilizing rod is set to stabilize the swirl flow field and increase the contact area of the gas-solid two-phase, Make the desulfurization reaction more complete.

4) The utility model has its own desulfurizer internal circulation device, that is, a coarse particle separation device is installed at the lower part of the attached tower to separate the incompletely reacted coarse particle calcium-based circulating ash, so that it can enter the main tower again for reaction, so it is extremely It greatly improves the utilization rate of the desulfurizer, significantly reduces the working pressure of the bag filter at the rear of the reactor, and prolongs the service life of the filter bag.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the utility model equipment.

detailed description

The implementation of the utility model will be described in detail below in conjunction with the accompanying drawings and examples.

Referring to Figure 1, a calcium-based circulating ash high solid-gas ratio cyclone desulfurization equipment includes a high solid-gas ratio cyclone desulfurization tower 1, and the high solid-gas ratio cyclone desulfurization tower 1 includes a main tower 2 and an auxiliary tower 3, the main tower 2. The upper part is a cylindrical barrel structure, the lower part is a conical structure, and the attached tower 3 is a cylindrical barrel structure; the coarse particle separation device 4 is a conical structure, which is arranged at the lower part of the attached tower 3, and is used for separating incompletely reacted coarse particles. For granular calcium-based circulating ash, a discharge lock valve 5 is set in the feed pipe of the coarse particle separation device 4; a central flow stabilizing rod 6 is arranged at the center of the upper section of the main tower 2 and the auxiliary tower 3 for stable rotation Shear turbulent flow field; bag filter 7, arranged at the rear of high solid-gas ratio cyclone desulfurization tower 1, used for flue gas dust removal and desulfurization ash capture; screw feeder 8, arranged in bag filter The lower part of 7 is used to send the desulfurized ash to the desulfurized ash bin 9 for storage; the lower part of the desulfurized ash bin 9 is provided with a gate valve 10, which is used to connect or cut off the supply path of the desulfurized ash; the three-way distributing valve 11 is arranged At the lower part of the gate valve 10, it is used to realize the external supply of desulfurized ash; one side of the three-way distribution valve 11 is connected to the air delivery chute 12, and is used to send the desulfurized ash to the humidification pool 16; the quicklime bin 13 The lower part is connected to the belt conveyor 14, which is used to send the quicklime particles into the digestion tank 15 for digestion, and the digested slaked lime particles are sent to the humidification tank 16, and are evenly mixed with the desulfurization ash and finally added with water to form a new calcium-based circulating ash .

The working process of the utility model:

First, the quicklime is digested in the digester 15, and then the digested slaked lime is mixed with the desulfurized ash captured by the bag filter 7 into the humidification pond 16, and water is added to form humidification ash, which is driven by fluidized wind and with the help of smoke The negative pressure of the channel enters the high solid-gas ratio swirl desulfurization tower 1, and the sulfur-containing flue gas and the humidified ash move around the center stabilizing rod 6 in the tower, and the ideal desulfurization reaction humidity and temperature are gradually formed during the movement. temperature conditions, the desulfurization process is finally completed, and the unreacted coarse particle humidified ash passes through the coarse particle separation device 4 and enters the tower again for reaction.

Claims (6)

1. a kind of calcium base circulating ash high solid-gas ratio cyclone desulfuration, including high solid-gas ratio cyclone desulfuration tower (1), it is characterised in that institute King-tower (2) and attached tower (3) that high solid-gas ratio cyclone desulfuration tower (1) includes top closure are stated, king-tower (2) top is cylindrical tube Structure, bottom are conical structure, and the attached tower (3) is cylindrical tube structure, and top is connected with king-tower (2) by horizontal channel Logical, bottom connects with sack cleaner (7), and the home position in the king-tower (2) and attached tower (3) middle section is respectively disposed with perpendicular To be used for stablize the center current stabilization bar (6) of rotational shear Turbulent Flow Field.

2. calcium base circulating ash high solid-gas ratio cyclone desulfuration equipment according to claim 1, it is characterised in that the attached tower (3) Bottom be bent into horizontal, have the coarse particle separating device (4) with discharging air valve (5) in the arranged beneath of crooked place, The coarse particle separating device (4) is conical structure, for separating the coarse granule calcium base circulating ash do not reacted completely, and loopback To the cylindrical tube structure bottom of king-tower (2).

3. calcium base circulating ash high solid-gas ratio cyclone desulfuration equipment according to claim 1, it is characterised in that the king-tower (2) Tangential air inlet structure be rectangular tube, rhumbatron or round tube, the tangential air inlet structure of the attached tower (3) is rectangular tube, rhombus Pipe or round tube.

4. according to the calcium base circulating ash high solid-gas ratio cyclone desulfuration equipment of claim 1 or 3, it is characterised in that the king-tower (2) tangential air inlet structure is cut with king-tower (2) cylinder spiral case or vertical cut, tangential air inlet structure and the attached tower of the attached tower (3) (3) incision of cylinder spiral case or vertical cut.

5. calcium base circulating ash high solid-gas ratio cyclone desulfuration equipment according to claim 1, it is characterised in that the bag-type dusting Device (7) receives out the flue gas and Desulphurization of attached tower (3), carries out flue gas ash removal and Desulphurization trapping, sack cleaner (7) bottom cloth Spiral batcher (8) is put, the Desulphurization of trapping is delivered into desulfurization ash silo (9) is stored.

6. calcium base circulating ash high solid-gas ratio cyclone desulfuration equipment according to claim 5, it is characterised in that the desulfurization ash silo (9) bottom is provided with the slide valve (10) for being used for connecting or block Desulphurization supply material road, and slide valve (10) lower disposed, which has, to be used for The T-piece splitting valve (11) that supply is arranged outside Desulphurization is realized, the side material road of T-piece splitting valve (11) is connected to send Desulphurization To the air conveyer flume (12) of humidification pond (16), quick lime storehouse (13) bottom is connect by belt conveyor (14) to be used for raw stone Ash particle is sent into the digester (15) digested, and postdigestive white lime particle is sent to humidification pond (16), equal with Desulphurization It is even to mix and finally add water to form calcium base circulating ash.