CN214345566U

CN214345566U - Carbide slag semi-dry desulfurization system

Info

Publication number: CN214345566U
Application number: CN202023037637.8U
Authority: CN
Inventors: 张新敏; 邱健; 侯奎; 任晓佳
Original assignee: Wuhan Leaway Engineering Technology Co ltd
Current assignee: Wuhan Leaway Engineering Technology Co ltd
Priority date: 2020-12-16
Filing date: 2020-12-16
Publication date: 2021-10-08
Anticipated expiration: 2030-12-16

Abstract

The utility model relates to a flue gas desulfurization technical field specifically discloses a carbide slag semidry process desulfurization system, including preparation and the conveying system of carbide slag thick liquid as the absorbent, the ash recycling system that flue gas desulfurization absorption system and absorbent recycled. The ash recycling system recycles the fly ash into the flue gas desulfurization absorption system by arranging the dust remover, the ash hopper and the return chute, so that the desulfurization efficiency and the desulfurization effect are improved; in addition, the system has the advantages of less overall equipment, simple and convenient and quick installation and construction, low cost and no waste water generation.

Description

Carbide slag semi-dry desulfurization system

Technical Field

The utility model relates to a flue gas desulfurization technical field, in particular to carbide slag semidry process desulfurization system.

Background

The carbide slag is waste slag which is obtained by hydrolyzing carbide to obtain acetylene gas and takes calcium hydroxide as a main component. Acetylene (C)₂H₂) Is one of the important raw materials of the basic organic synthesis industry, and is prepared from calcium carbide (CaC)₂) The process for producing acetylene by adding water (wet method) as raw material is simple and mature, and currently occupies a large proportion in China. About 300kg of acetylene gas can be generated by adding water into 1t of calcium carbide, and 10t of industrial waste liquid with the solid content of about 12 percent is generated at the same time, and is commonly called as calcium carbide slurry. The chemical reaction is as follows:

carbide slag is a paste based on calcium hydroxide accompanied by oxides or hydrides of silicon, iron, aluminum, magnesium, sulfur, phosphorus, and is disposed of as a solid waste in many plants. The hydrolyzed carbide slag contains not only about 90% of calcium hydroxide, but also various impurities, such as Si, Fe, Al, Mg, S, P, etc. which are mixed in the carbide and become SiO after hydrolysis₂、Fe(OH)₃、Al(OH)₃、Mg(OH)₂、H₂S↑、PH₃And ×) and the like. The fineness of the carbide slag generated after hydrolysis is 260-300 meshes, and the hydrolysate contains a large amount of hydroxide, so that the carbide slag aqueous solution is strong in basicity and has strong neutralizing capacity on acid gases.

No better treatment method is available at home and abroad to recycle the carbide slag, and the carbide slag is not treated and pollutes rivers and silts up the rivers. The carbide slag is used as a desulfurizer instead of limestone, so that the problem of the carbide slag is solved fundamentally. On the other hand, the carbide slag is used as a low-cost desulfurizer, and the desulfurization cost can be reduced. Meanwhile, carbide slag is used as a desulfurizer, so that the emission of carbon dioxide can be reduced.

The currently adopted dry desulfurization process needs to dry the carbide slag, and the commonly adopted method is two modes of utilizing drying equipment or flue gas to heat and evaporate water, wherein the energy consumption of the drying equipment is higher, and the desulfurization activity of the hot flue gas can be reduced due to the direct contact of the hot flue gas and the carbide slag.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a carbide slag semidry process desulfurization system to solve among the prior art problem that the energy consumption is high, desulfurization efficiency is low and with high costs.

In order to realize the aim, the utility model provides a carbide slag semi-dry desulphurization system, which comprises a preparation and conveying system taking carbide slag slurry as an absorbent, a flue gas desulphurization absorption system and an ash recycling system recycling the absorbent; the ash recycling system comprises a dust remover, an ash hopper and a return chute; the dust remover is communicated with an air outlet channel of the desulfurization absorption system, the ash hopper is arranged at the lower end of an ash outlet of the dust remover, the return chute is arranged at the bottom of the ash hopper and communicated with a flue gas inlet of the desulfurization absorption system, and an opening is arranged on the upper side of the part of the return chute, which is positioned in the ash hopper.

Furthermore, an ash discharging gate valve and a metal compensator are further arranged at an ash outlet of the dust remover.

Furthermore, an electric shutoff valve and a pneumatic regulating valve for regulating the ash flow are arranged at the communicating part of the return chute and the flue gas inlet of the desulfurization absorption system.

The utility model provides a system for semi-dry desulfurization of carbide slag, wherein the system for preparing and conveying carbide slag slurry absorbent comprises a carbide slag bin, a gate valve, a screw conveyor, a slurry tank with an opening at the upper end and a stirrer arranged in the slurry tank; the gate valve is located carbide slag bin discharge gate, and screw conveyer is located the discharge gate below, and the thick liquid case is located screw conveyer discharge end below.

Further, the preparation and conveying system for the carbide slag slurry absorbent further comprises a process water tank, a process water pump, a slurry pump and a slurry spray gun; the process water tank is communicated with the slurry tank by a process water pump, and the lower part of the slurry tank is communicated with the inlet of the slurry spray gun by the slurry pump.

Further, the process water tank is communicated with the inlet of the slurry spray gun through another process water pump.

The utility model provides an among carbide slag semi-dry desulfurization system, flue gas desulfurization absorption system goes up the venturi of circular cone mouth and desulfurization absorption tower air inlet intercommunication including setting up the desulfurization absorption tower on upper portion, the lower circular cone mouth of venturi is equipped with the flue gas entry, venturi intercommunication the export of thick liquid spray gun.

Further, the throat of the venturi is in communication with the outlet of the slurry lance.

Further, the return chute is communicated with an upper conical opening of the venturi.

Compared with the prior art, the beneficial effects of the utility model reside in that:

1. the utility model provides an among the semidry desulfurization system, regard as the desulfurization absorbent with the carbide slag, can the furthest solution carbide slag go out of the way, the carbide slag is compared with lime stone commonly used as a low-cost desulfurizer, can reduce the desulfurization cost on the one hand, can reduce carbon dioxide's emission simultaneously, is favorable to the construction of carbon neutralization.

2. The utility model provides an among the semidry process desulfurization system, adopt the spraying to combine the flue gas waste heat to realize the thick liquid drying, overcome prior art carbide slag thick liquid extra dehydration drying's process, realized that equipment retrencies, reduces the energy consumption, the cost is reduced.

3. The utility model provides an among the semidry desulfurization system, through adopting grey circulation system, carbide slag is circulated about 100 times, has promoted desulfurization efficiency and desulfurization effect. In addition, the system has the advantages of less overall equipment, simple and convenient and quick installation and construction, low cost and no waste water generation.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is the overall schematic diagram of the semi-dry carbide slag desulfurization system of the present invention.

In the figure: 1. a carbide slag bin; 2. a gate valve; 3. a screw conveyor; 4. a slurry tank; 5. a stirrer; 6. a process water tank; 7. a process water pump; 8. a slurry pump; 9. a spray gun; 10. a desulfurization absorption tower; 11. a venturi; 12. a dust remover; 13. an ash hopper; 14. a return chute; 15. ash discharging gate valves; 16. a metal compensator; 17. an electrically operated shutoff valve; 18. pneumatic control valve.

Detailed Description

In order to make the objects, technical solutions and advantageous technical effects of the present invention more clearly understood, the present invention is further described in detail with reference to the accompanying drawings and the following detailed description. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration only and not by way of limitation.

Referring to the attached drawing 1, the utility model discloses a carbide slag semi-dry desulfurization system, including preparation and the conveying system of carbide slag thick liquid absorbent, flue gas desulfurization absorption system, ash recycling system that the absorbent was recycled.

Wherein:

the preparation and conveying system of the carbide slag slurry absorbent comprises a carbide slag bin 1 for storing carbide slag, a gate valve 2 for starting and stopping blanking, a screw conveyor 3 for conveying the carbide slag, a slurry tank 4 for reacting the carbide slag and a stirrer 5 arranged in the slurry tank 4; the gate valve 2 is located carbide slag bin 1 lower part discharge gate, and screw conveyer 3 is located gate valve 2 below, and the upper end opening of thick liquid case 4 is located screw conveyer 3 discharge end below.

In addition, the preparation and conveying system of the carbide slag slurry absorbent also comprises a process water tank 6 for water storage, a process water pump 7, a slurry pump 8 and a slurry spray gun 9; the process water tank 6 is communicated with two process water pumps 7 through pipelines, the first process water pump 7 is communicated with the upper part of the slurry tank 4, and the lower part of the slurry tank 4 is communicated with the slurry pump 8 and converged into an inlet of a slurry spray gun 9 through an output pipeline of the second process water pump 7.

The flue gas desulfurization absorption system comprises a desulfurization absorption tower 10 arranged at the upper part, and a venturi 11 communicated with the desulfurization absorption tower 10 at the lower part; the lower port of the venturi 11 is provided with a flue gas inlet, and the outlet of the slurry spray gun 9 is communicated with the throat part of the venturi 11.

The ash recycling system comprises a dust remover 12, an ash hopper 13 and a return chute 14; the dust remover 12 is communicated with the air outlet channel of the desulfurization absorption tower 10, the ash hopper 13 is arranged at the lower end ash outlet of the dust remover 12, the return chute 14 is arranged at the bottom of the ash hopper 13 and is communicated with an upper cone communicated with the venturi 11, and an opening is arranged on one section of the upper side edge of the return chute 14 positioned in the ash hopper 13. Further, an ash discharging gate valve 15 and a metal compensator 16 are also arranged at an ash outlet of the dust remover 12; an electric shutoff valve 17 and a pneumatic control valve 18 for adjusting the ash flow are arranged at the connection part of the return chute 14 and the venturi 11.

Further, the semi-dry carbide slag desulfurization system further comprises a flue gas volume and a SO (sulfur oxide) volume which are arranged at the outlet of the dust remover 12₂A concentration detection system and an on-line measurement system of the temperature of the flue gas.

The working process and principle of the carbide slag semi-dry desulphurization system of the utility model are explained in the following by combining the attached drawings.

As shown in figure 1, the carbide slag is sent into a carbide slag bin 1 from a factory or outside for storage, a gate valve 2 and a screw feeder 3 are arranged at the bottom of the bin, the normal blanking of the carbide slag is ensured, and meanwhile, the concentration of the absorbent conveyed to a slurry tank 4 is controlled by controlling the rotating speed of the screw feeder 3 and the water supply amount of a process water pump 7. Preferably, the mass concentration of the carbide slag slurry is 35-50%.

The stirrer 5 in the slurry tank 4 continuously stirs to ensure that the slurry is uniformly mixed, and the uniformly mixed carbide slag slurry is sprayed into the desulfurization absorption tower 10 through the slurry pump 8, the incoming water of the process water tank 6 and the plant area compressed air together through the spray gun 9. Furthermore, another process water pump 7 is also communicated to the spray gun 9, and the slurry can be diluted or the water can be directly fed to clean the equipment.

Raw flue gas from the boiler enters from the bottom of the desulfurization absorption tower 10 and is sprayed into the desulfurization absorption towerThe carbide slag slurry rises together through the venturi 11 in an accelerating way, and the carbide slag slurry and SO in the flue gas in the drying process₂And the acid gas is absorbed by neutralization reaction.

The desulfurized flue gas is discharged into the atmosphere through a chimney after dust and ash are removed by a dust remover 12.

The mixture containing the desulfurization product particles, the residual carbide slag and the fly ash is separated by a dust collector 12 and enters an ash hopper 13, a part of the mixture in the ash hopper 13 is collected into an ash bin, and a part of the mixture enters a return chute 14 through the ash discharged from the ash hopper 13 and returns to the desulfurization absorption tower 10. The carbide slag which is not completely reacted in the mixture continuously reacts with the acidic substances in the flue gas, so that the utilization rate of the desulfurizer is improved to the maximum extent.

In the carbide slag semi-dry desulfurization system of the utility model, the sprayed carbide slag slurry, the desulfurization by-products and the fly ash circulate together in the dust remover 12, the ash bucket 13 and the desulfurization absorption tower 10, so that the fresh carbide slag slurry is coated on the surface of the fly ash, and has a larger contact surface with the flue gas, and the desulfurization effect is further improved; wherein 99 percent of the bed materials are sent back to the desulfurization absorption tower 10 for circulation through the pneumatic adjusting valve 18 on the material returning chute 14, and only about 1 percent of the bed materials are discharged out of the system as desulfurization ash.

Further, an electric shutoff valve 17 and a pneumatic control valve 18 arranged on the return chute 14 are used for adjusting the circulating ash amount in the desulfurization absorption tower 10 and keeping the bed pressure stable under different working conditions.

Further, by monitoring the amount of the outlet flue gas and SO₂Controlling the addition amount of the carbide slag according to the concentration; the temperature-adjusting water quantity of the carbide slag slurry is controlled by the online measurement of the temperature of the outlet flue gas.

The invention is not limited solely to that described in the specification and the embodiments, and additional advantages and modifications will readily occur to those skilled in the art, and it is not intended to be limited to the specific details, representative apparatus, and illustrative examples shown and described herein, without departing from the spirit and scope of the general concept as defined by the appended claims and their equivalents.

Claims

1. A semi-dry desulfurization system for carbide slag comprises a preparation and conveying system for carbide slag slurry as an absorbent and a flue gas desulfurization absorption system, and is characterized by also comprising an ash recycling system for recycling the absorbent; the ash recycling system comprises a dust remover (12), an ash hopper (13) and a return chute (14); dust remover (12) and desulfurization absorption system air outlet channel intercommunication, ash bucket (13) set up the ash outlet lower extreme in dust remover (12), return chute (14) set up in the bottom of ash bucket (13) and with the flue gas air inlet that communicates desulfurization absorption system, return chute (14) are located the inside part upside limit of ash bucket (13) and have the opening.

2. The semi-dry desulfurization system according to claim 1, wherein the ash outlet of the dust collector (12) is further provided with an ash discharge gate valve (15) and a metal compensator (16).

3. The semi-dry desulfurization system according to claim 1, wherein an electric shutoff valve (17) and a pneumatic control valve (18) for adjusting the ash flow are arranged at the connection between the return chute (14) and the flue gas inlet of the desulfurization absorption system.

4. The semi-dry desulfurization system of claim 1, wherein the carbide slag slurry absorbent preparation and delivery system comprises: the device comprises a carbide slag bin (1), a gate valve (2), a screw conveyor (3), a slurry box (4) with an opening at the upper end and a stirrer (5) arranged in the slurry box (4); the gate valve (2) is positioned at the discharge hole of the carbide slag bin (1), the screw conveyor (3) is positioned below the discharge hole, and the slurry box (4) is positioned below the discharge end of the screw conveyor (3).

5. The semi-dry desulfurization system according to claim 4, wherein the preparation and delivery system for the carbide slag slurry absorbent further comprises a process water tank (6), a process water pump (7), a slurry pump (8) and a slurry spray gun (9); the process water tank (6) is communicated with the slurry tank (4) through a process water pump (7), and the lower part of the slurry tank (4) is communicated with the inlet of a slurry spray gun (9) through a slurry pump (8).

6. Semi-dry desulphurization system according to claim 5, wherein the process water tank (6) is connected to the inlet of the slurry lance (9) through another process water pump (7).

7. The semi-dry desulfurization system according to claim 5, wherein the flue gas desulfurization absorption system comprises a desulfurization absorption tower (10) arranged at the upper part, a venturi (11) with an upper conical opening communicated with the gas inlet of the desulfurization absorption tower (10), a flue gas inlet arranged at the lower conical opening of the venturi (11), and an outlet communicated with the slurry spray gun (9) through the venturi (11).

8. Semi-dry desulfurization system according to claim 7, characterized in that the throat of the venturi (11) is in communication with the outlet of the slurry lance (9).

9. Semi-dry desulphurization system according to claim 7, wherein the return chute (14) communicates with the upper conical mouth of the venturi (11).