Dry deacidification system for superfine calcium powder in low-sulfur flue gas

Abstract

The utility model discloses a dry deacidification system for superfine calcium powder in low-sulfur flue gas. The dry deacidification system comprises a superfine calcium powder bin, an arch breaking gasification mechanism, a rotary feeding mechanism, a weighing metering mechanism, a discharging pneumatic valve, a variable-frequency feeding mechanism, a gas lock, a dry ejector, a gas guide pipeline, a Roots blower, an ejection pipeline and a deacidification reaction tower. According to the utility model, the ultrafine powder can be directly sprayed into the flue through the efficient ejector, the absorption reaction is finished in the flue gas flowing process, the investment is saved, the power consumption, the resistance and the water consumption are low, the influence of the flue gas temperature is avoided, the effective reaction can be realized above normal temperature, the desulfurization efficiency is high, the desulfurizer source is wide, the by-product is less, the by-product is common solid waste, and no waste water is generated; the environmental pollution is favorably reduced.

Description

[Technical field]

[0001] The utility model relates to the technical field of low-sulfur flue gas deacidification, in particular to the technical field of a low-sulfur flue gas ultrafine calcium powder dry method deacidification system. [Background technology]

[0002] Low-sulfur flue gas is produced during the production process of biomass boilers, cement kilns, glass kilns, coke ovens and other equipment. The pollutants in low-sulfur flue gas will cause harm to the environment. Therefore, when low-sulfur flue gas is discharged, it is usually necessary to carry out deacidification to reduce pollutants. At present, the main low-sulfur flue gas deacidification technologies include SDA semi-dry deacidification system, dry (SDS) sodium bicarbonate deacidification system, wet deacidification system and calcium agent dry deacidification system. When the SDA semi-dry deacidification process is adopted, the process is complex, the land is large, and the one-time investment and operating costs are high; when the dry (SDS) sodium bicarbonate deacidification process is adopted, the process is simple, the operating cost is high, the sodium-based consumption is high at high temperature, the sodium-based adsorbent dissolves in water, penetrates into the soil and water, causing pollution, and the problem of treating sodium-containing ash needs to be solved; when the wet deacidification process is adopted, wastewater is generated and the cost of wastewater treatment is high, acid corrosion occurs in the chimney, and the chimney produces white fog. The operation and maintenance workload is large, the energy consumption is high, and the one-time investment and operating costs are high; when the conventional calcium hydroxide dry deacidification process is adopted, the reaction temperature window range is narrow and the deacidification efficiency is low. [Contents of the utility model]

[0003] The purpose of the utility model is to solve the problems in the prior art and propose a low-sulfur flue gas ultrafine calcium powder dry deacidification system, which can directly spray ultrafine powder into the flue through a high-efficiency injector to complete the absorption reaction during the flow of flue gas, with low investment, low power consumption, low resistance, and low water consumption. It is not affected by the flue gas temperature and can effectively react above room temperature. It has high desulfurization efficiency, a wide source of desulfurizers, and fewer by-products. The by-products are general solid wastes, and no wastewater is generated, which is beneficial to reducing environmental pollution.

[0004] To achieve the above-mentioned purpose, the utility model proposes a low-sulfur flue gas ultrafine calcium powder dry deacidification system, comprising an ultrafine calcium powder silo, an arch breaking gasification mechanism, a rotary feeding mechanism, a weighing and metering mechanism, a discharging pneumatic valve, a variable frequency feeding mechanism, an air lock, a dry ejector, an air guide pipe, a Roots blower, an injection pipe and a deacidification reaction tower, wherein the ultrafine calcium powder silo is provided with an arch breaking gasification mechanism at the lower part, the ultrafine calcium powder silo is connected with a rotary feeding mechanism at the bottom, the rotary feeding mechanism is connected with a weighing and metering mechanism at the bottom, a discharging pneumatic valve is provided at the connection part between the weighing and metering mechanism and the rotary feeding mechanism, a variable frequency feeding mechanism is provided at the lower part of the weighing and metering mechanism, the bottom of the variable frequency feeding mechanism is connected with the dry ejector through an air lock, the left end of the dry ejector is connected with the Roots blower through the air guide pipe, and the right end of the dry ejector is connected with the deacidification reaction tower through the injection pipe.

[0005] Preferably, a vulcanization solenoid valve and a pressure reducing valve are sequentially connected to the outer side of the arch-breaking gasification mechanism, and the outer end of the pressure reducing valve is connected to a compressed gas source for fluidization.

[0006] Preferably, the rotary feeding mechanism is any one of a disc feeder, a bidirectional screw feeder and a multi-bin variable frequency screw feeder.

[0007] Preferably, the top of the ultrafine calcium powder silo is connected to the ultrafine calcium powder tank truck.

[0008] Preferably, an outlet pressure transmitter is provided at the connection portion between the Roots blower and the dry ejector.

[0009] Preferably, the ultrafine calcium powder in the ultrafine calcium powder silo is ultrafine calcium hydroxide powder with high activity and high specific surface area.

[0010] Preferably, the variable frequency feeding mechanism is a high-precision variable frequency rotary feeder.

[0011] Preferably, the exhaust portion of the deacidification reaction tower is connected to a flue gas dust collector.

[0012] Beneficial effects of the utility model: The utility model combines the ultrafine calcium powder silo, the arch breaking gasification mechanism, the rotary feeding mechanism, the weighing and metering mechanism, the discharging pneumatic valve, the frequency conversion feeding mechanism, the air lock machine, the dry method ejector, the air guide pipe, the Roots blower, the injection pipe and the deacidification reaction tower together, and after experimental optimization, the ultrafine calcium hydroxide dry powder deacidification agent with high activity and high specific surface area is directly injected into the flue or CFB tower or NID reactor through the Roots blower. Under the action of the high-efficiency ejector, it quickly diffuses into the flue gas, adsorbs and absorbs most of the acidic media such as F-, Cl-, SO2 and SO3 in the flue gas, and enters the bag filter or ceramic filter cartridge dust collector or metal filter cartridge dust collector with the flue gas. A small part of the acidic media continues to react in the dust collector. The flue gas after deacidification is directly discharged through the induced draft fan, with high desulfurization efficiency, high activity and high specific surface area. Ultrafine calcium hydroxide has the characteristics of porous, high activity, good dispersibility and high utilization rate. Its specific surface area is the highest among ordinary 3-4 times or more of calcium hydroxide, using high-precision rotary feeder, frequency conversion measurement or weighing measurement through sensors, the outlet SO2 concentration can reach 35mg / Nm3 and below; the flue gas sulfur dioxide concentration is between 50 and 350mg / Nm3, the process is simple, the ultrafine powder is directly sprayed into the flue through an efficient injector, and the absorption reaction is completed during the flue gas flow. It is especially suitable for transformation on the basis of low-sulfur traditional deacidification process, and perfectly replaces SDA semi-dry process and SDS baking soda process in the field of low-sulfur flue gas, saving investment, solving the problem of low-sulfur flue gas deacidification, low power consumption, low resistance, low water consumption, avoiding equipment and chimney corrosion, this process is not affected by the flue gas temperature, can effectively react above room temperature, the reaction temperature range is 35-350℃, no wastewater is generated, the desulfurizer source is wide, and there are fewer by-products. The by-products are general solid wastes, and the by-products are saturated waste desulfurizers, with the main components being CaSO4, Ca(OH)2, and CaCO3.

[0013] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0014] Figure 1 This is a schematic diagram of the structure of the utility model low-sulfur flue gas ultrafine calcium powder dry deacidification system;

[0015] Figure 2 It is a schematic diagram of the injection structure of the low-sulfur flue gas ultrafine calcium powder dry deacidification system of the utility model.

[0016] In the figure: 1-ultrafine calcium powder silo, 2-arch breaking gasification mechanism, 3-rotary feeding mechanism, 4-weighing metering mechanism, 5-discharging pneumatic valve, 6-frequency conversion feeding mechanism, 7-air lock machine, 8-dry ejector, 9-air guide pipe, 10-Roots blower, 11-injection pipe, 12-deacidification reaction tower. [Specific implementation method]

[0017] See also Figure 1 and Figure 2 The utility model discloses a low-sulfur flue gas ultrafine calcium powder dry deacidification system, comprising an ultrafine calcium powder silo 1, an arch breaking gasification mechanism 2, a rotary feeding mechanism 3, a weighing and metering mechanism 4, a discharging pneumatic valve 5, a variable frequency feeding mechanism 6, an air lock 7, a dry method ejector 8, an air guide duct 9, a Roots blower 10, an ejection duct 11 and a deacidification reaction tower 12, wherein the ultrafine calcium powder silo 1 is provided with an arch breaking gasification mechanism 2 at the lower part, the ultrafine calcium powder silo 1 is connected with a rotary feeding mechanism 3 at the bottom, the rotary feeding mechanism 3 is connected with a weighing and metering mechanism 4 at the bottom, a discharging pneumatic valve 5 is provided at the connection portion between the weighing and metering mechanism 4 and the rotary feeding mechanism 3, a variable frequency feeding mechanism 6 is provided at the lower part of the weighing and metering mechanism 4, the bottom of the variable frequency feeding mechanism 6 is connected with the dry method ejector 8 through the air lock 7, the dry method ejector 8 The left end is connected with the Roots blower 10 through the air guide pipe 9, the right end of the dry ejector 8 is connected with the deacidification reaction tower 12 through the injection pipe 11, the outer side of the arch breaking gasification mechanism 2 is connected with a vulcanization solenoid valve and a pressure reducing valve in sequence, the outer end of the pressure reducing valve is connected to the compressed air source for fluidization, the rotary feeding mechanism 3 is any one of a disc feeder, a bidirectional screw feeder and a multi-bin variable frequency screw feeder, the top of the ultrafine calcium powder silo 1 is connected with the ultrafine calcium powder tank loading truck, the connection part of the Roots blower 10 and the dry ejector 8 is provided with an outlet pressure transmitter, the ultrafine calcium powder in the ultrafine calcium powder silo 1 is a highly active, high specific surface area ultrafine calcium hydroxide powder, the variable frequency feeding mechanism 6 is a high-precision variable frequency rotary feeder, and the exhaust part of the deacidification reaction tower 12 is connected with a flue gas dust collector.

[0018] The utility model combines an ultrafine calcium powder silo 1, an arch breaking gasification mechanism 2, a rotary feeding mechanism 3, a weighing and metering mechanism 4, a discharging pneumatic valve 5, a frequency conversion feeding mechanism 6, an air lock machine 7, a dry method ejector 8, an air guide pipe 9, a Roots blower 10, an ejection pipe 11 and a deacidification reaction tower 12 together. After experimental optimization, an ultrafine calcium hydroxide dry powder deacidification agent with high activity and high specific surface area is transported by the Roots blower 10 and directly injected into the flue or CFB tower or NID reactor. Under the action of the high-efficiency ejector, the calcium oxide powder quickly diffuses into the flue gas, adsorbs and absorbs most of the acidic media such as F-, Cl-, SO2 and SO3 in the flue gas, and enters the bag filter or ceramic filter cartridge filter or metal filter cartridge filter with the flue gas. A small part of the acidic media continues to react in the dust collector. The flue gas after deacidification is directly discharged through the induced draft fan, with high desulfurization efficiency, high activity and high specific surface area. Ultrafine calcium hydroxide has the characteristics of porous, high activity, good dispersibility, high utilization rate, and specific surface area. It is 3-4 times or more than that of ordinary calcium hydroxide. It adopts high-precision rotary feeder and performs frequency conversion measurement or weighing measurement through sensors. The outlet SO2 concentration can reach 35mg / Nm3 and below; the flue gas sulfur dioxide concentration is between 50 and 350mg / Nm3. The process is simple. The ultrafine powder is directly sprayed into the flue through an efficient injector to complete the absorption reaction during the flow of flue gas. It is especially suitable for transformation based on the traditional low-sulfur deacidification process. In the field of low-sulfur flue gas, it perfectly replaces the SDA semi-dry process and the SDS baking soda process. It saves investment and solves the problem of low-sulfur flue gas deacidification. It has low power consumption, low resistance, and low water consumption, avoiding corrosion of equipment and chimneys. This process is not affected by the flue gas temperature and can react effectively above room temperature. The reaction temperature range is 35-350℃, no wastewater is generated, the desulfurizer has a wide source, and there are fewer by-products. The by-products are general solid wastes and saturated waste desulfurizers. The main components are CaSO4, Ca(OH)2, and CaCO3.

[0019] The above embodiments are intended to illustrate the present invention, not to limit the present invention. Any solution that is a simple transformation of the present invention falls within the protection scope of the present invention.

Claims

1. Low-sulfur flue gas ultrafine calcium powder dry deacidification system, characterized by: The invention comprises an ultrafine calcium powder silo (1), an arch-breaking gasification mechanism (2), a rotary feeding mechanism (3), a weighing and metering mechanism (4), a discharging pneumatic valve (5), a variable frequency feeding mechanism (6), an air lock (7), a dry method ejector (8), an air guide pipe (9), a Roots blower (10), an ejection pipe (11) and a deacidification reaction tower (12), wherein the ultrafine calcium powder silo (1) is provided with an arch-breaking gasification mechanism (2) at the lower part, the ultrafine calcium powder silo (1) is connected to the rotary feeding mechanism (3) at the bottom, and the rotary feeding mechanism (3) is connected to the bottom of the rotary feeding mechanism (3). A weighing and metering mechanism (4) is provided, and a discharging pneumatic valve (5) is provided at the connection portion between the weighing and metering mechanism (4) and the rotary feeding mechanism (3). A variable frequency feeding mechanism (6) is provided at the lower part of the weighing and metering mechanism (4). The bottom of the variable frequency feeding mechanism (6) is connected to a dry ejector (8) through an air lock (7). The left end of the dry ejector (8) is connected to a Roots blower (10) through an air guide pipe (9), and the right end of the dry ejector (8) is connected to a deacidification reaction tower (12) through an ejection pipe (11).

2. The low-sulfur flue gas ultrafine calcium powder dry deacidification system according to claim 1, characterized in that: The outer side of the arch-breaking gasification mechanism (2) is connected in sequence with a vulcanization solenoid valve and a pressure reducing valve, and the outer end of the pressure reducing valve is connected to a compressed gas source for fluidization.

3. The low-sulfur flue gas ultrafine calcium powder dry deacidification system according to claim 1, characterized in that: The rotary feeding mechanism (3) is any one of a disc feeder, a bidirectional screw feeder and a multi-bin variable frequency screw feeder.

4. The low-sulfur flue gas ultrafine calcium powder dry deacidification system according to claim 1, characterized in that: The top of the ultrafine calcium powder silo (1) is connected to the ultrafine calcium powder tank loading vehicle.

5. The low-sulfur flue gas ultrafine calcium powder dry deacidification system according to claim 1, characterized in that: An outlet pressure transmitter is provided at the connection portion between the Roots blower (10) and the dry ejector (8).

6. The low-sulfur flue gas ultrafine calcium powder dry deacidification system according to claim 1, characterized in that: The ultrafine calcium powder in the ultrafine calcium powder silo (1) is ultrafine calcium hydroxide powder with high activity and high specific surface area.

7. The low-sulfur flue gas ultrafine calcium powder dry deacidification system according to claim 1, characterized in that: The variable frequency feeding mechanism (6) is a high-precision variable frequency rotary feeder.

8. The low-sulfur flue gas ultrafine calcium powder dry deacidification system according to claim 1, characterized in that: The exhaust portion of the deacidification reaction tower (12) is connected to a flue gas dust collector.

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