Semi-dry desulfurization ash on-line treatment system

Abstract

The utility model discloses an online treatment system for semi-dry desulfurization ash, and relates to the technical field of environmental engineering. The device comprises an oxidation fan, an oxidation reactor and a dust remover, an inlet of the oxidation fan is connected with a front flue of a semi-dry desulfurization absorption tower, and an outlet of the dust remover is connected with an inlet section of the semi-dry desulfurization absorption tower; the oxidation reactor is provided with a feed port, a discharge port, an air inlet, an air outlet, a return port, a water inlet and an oxidation auxiliary inlet; a feed port of the oxidation reactor is connected with a desulfurized ash discharge port of a semi-dry desulfurization system, a discharge port is communicated to a desulfurized ash warehouse through an ash discharge device, an air inlet is connected with an outlet of an oxidation fan, an air outlet is connected with an inlet of a dust remover, and a return port is connected with an ash discharge port of the dust remover; the semi-dry desulfurization system is simple and reasonable in structure, can be directly modified on the basis of the existing semi-dry desulfurization system, can utilize flue gas to be treated to oxidize and dry desulfurized fly ash, realizes one-box treatment, does not need an additional heat source and the like, also can improve the utilization rate of a desulfurizer, and is low in operation cost.

Description

TECHNICAL FIELD

[0001] The utility model relates to environmental engineering technical field, concretely is a kind of semi-dry method desulfurization ash online disposal system. BACKGROUND

[0002] Desulfurization ash is the by-product collected by dust removal system after desulfurization in semi-dry method flue gas desulfurization process, and its composition mainly includes calcium sulfate (CaSO4), calcium sulfite (CaSO3), unreacted desulfurizer Ca (OH) 2 and the like, wherein the proportion of calcium sulfate is generally only 30~50%.Due to the unstable chemical properties of calcium sulfite, the high content of calcium sulfite seriously limits the comprehensive utilization of desulfurization ash, leading to secondary pollution;At the same time, the existence of unreacted desulfurizer Ca (OH) 2 makes the utilization efficiency of desulfurizer low, and the composition of desulfurization ash is complex.

[0003] For the disposal of calcium sulfite in desulfurization ash, there are different methods such as high-temperature oxidation and low-temperature oxidation.For example, the patent CN114409290A discloses a device and method for modifying desulfurization ash based on blast furnace gas, which uses blast furnace gas as heat source fuel to oxidize desulfurization ash at a temperature of 300~450℃.Although the oxidation temperature is lower than the decomposition temperature, high-calorific fuel is still consumed, the system is complex, the land occupation is large, and the economy is poor.Furthermore, the patent CN109455752A discloses a method and device for preparing calcium sulfate from desulfurization ash, which reacts desulfurization ash with strong oxidizing agent in solution state to realize low-temperature oxidation, but this method needs to adjust pH value, and needs to be dried by pressure filtration after oxidation, which is complex in operation, and produces waste water, forming secondary pollution.Furthermore, the patent CN112875740B discloses a system and method for preparing high-purity gypsum from semi-dry method desulfurization ash, which converts calcium oxide and calcium sulfite in semi-dry method desulfurization ash into gypsum by using wet desulfurization system.Although this method uses existing wet desulfurization system to dispose desulfurization ash, it still has the problem of transportation of semi-dry method desulfurization ash, and needs to build a wet desulfurization system within the transportation distance to realize it.In summary, a semi-dry method desulfurization ash online disposal system is needed to solve these problems. UTILITY MODEL CONTENTS

[0004] The utility model aims at providing a kind of semi-dry method desulfurization ash online disposal system to solve the problems of high energy consumption, easy to produce waste water and secondary pollution, and system is not simple enough in prior art semi-dry method desulfurization ash disposal.

[0005] To achieve the above object, the utility model provides the following technical scheme: A kind of semi-dry method desulfurization ash online disposal system, including oxidation fan, oxidation reactor, dust collector, oxidation fan inlet is connected with the flue before semi-dry method desulfurization absorption tower, and dust collector outlet is connected with semi-dry method desulfurization absorption tower inlet section;Oxidation reactor is equipped with feed inlet, discharge outlet, air inlet, air outlet, return material port, water inlet, oxidation auxiliary agent inlet;The feed inlet of oxidation reactor is connected with the desulfurization ash discharge outlet of semi-dry method desulfurization system, and discharge outlet is communicated to desulfurization ash storehouse by ash discharging device, air inlet is connected with oxidation fan outlet, air outlet is connected with dust collector inlet, and return material port is connected with the ash discharge port of dust collector.

[0006] Preferably, oxidation fan is variable frequency regulation fan, and is equipped with adjustable damper.

[0007] Preferably, oxidation reactor's oxidation auxiliary agent inlet is connected with external oxidation auxiliary agent supply equipment.

[0008] Preferably, oxidation reactor is equipped with stirring device inside.

[0009] Preferably, oxidation reactor's feed inlet, air inlet, water inlet, oxidation auxiliary agent inlet are all provided with flow metering instrument and control valve.

[0010] Compared with prior art, the utility model has the beneficial effects that:

[0011] 1、The semi-dry method desulfurization ash online disposal system, simple structure is reasonable, can be directly transformed on the basis of traditional semi-dry method desulfurization system, just need to draw out pipe connection from semi-dry method desulfurization absorption tower flue and inlet section respectively, without need of disposing in different places, can realize " solid waste not to leave factory", and investment cost is low.

[0012] 2、The semi-dry method desulfurization ash online disposal system, utilizes the oxygen and temperature of semi-dry method to be handled flue gas itself, and carries out oxidation and drying to semi-dry method desulfurization ash, does not need to increase heat source additionally, and operating cost is low.

[0013] 3、The semi-dry method desulfurization ash online disposal system, SO2 in flue gas and the desulfurizer Ca (OH) 2 that is not reacted completely in desulfurization ash fully react, indirectly improves the utilization efficiency of desulfurizer, and further reduces operating cost.

[0014] 4、The semi-dry method desulfurization ash online disposal system, the water added in disposal process becomes water vapor in oxidation, drying process, returns to original semi-dry method desulfurization system with flue gas, and no secondary pollution such as waste water is generated, and the desulfurization ash after disposal is dry powder state, convenient for storage and subsequent secondary utilization.

[0015] 5、The semi-dry desulfurization ash online disposal system is an online disposal system, can control the oxidation time of the desulfurization ash by adjusting the amount of oxidized flue gas and the amount of oxidation auxiliary agent, can match the ash discharge period of the original semi-dry desulfurization system by regulating the time, has high oxidation efficiency, has flexible control means and can realize continuous large-scale production. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is a system schematic view of the utility model;

[0017] Figure 2 It is a structure schematic view of the oxidation reactor of the utility model.

[0018] In the drawing: 1-oxidation fan; 2-oxidation reactor; 201-feed inlet; 202-discharge outlet; 203-air inlet; 204-air outlet; 205-return material port; 206-water inlet; 207-oxidation auxiliary agent inlet; 3-dust collector; 4-ash discharging device; 5-desulfurization ash storage. DETAILED DESCRIPTION

[0019] Referring to Figure 1 and Figure 2 A semi-dry desulfurization ash online disposal system, including oxidation fan 1, oxidation reactor 2, dust collector 3, oxidation fan 1 inlet is connected with the front flue of semi-dry desulfurization absorption tower, and dust collector 3 outlet is connected with the inlet section of semi-dry desulfurization absorption tower;Oxidation reactor 2 is equipped with feed inlet 201, discharge outlet 202, air inlet 203, air outlet 204, return material port 205, water inlet 206, oxidation auxiliary agent inlet 207, wherein air inlet 203 generally is connected to the lower part of oxidation reactor 2, increases the contact time of flue gas and internal slurry, and air outlet 204 is connected to the upper end of oxidation reactor 2;The feed inlet 201 of oxidation reactor 2 is connected with the desulfurization ash discharge port of semi-dry desulfurization system, and the discharge outlet 202 is communicated to the desulfurization ash storage 5 through the ash discharging device 4, the air inlet 203 is connected with the outlet of oxidation fan 1, the air outlet 204 is connected with the inlet of dust collector 3, and the return material port 205 is connected with the ash discharge port of dust collector 3.

[0020] In a more preferred embodiment, the oxidation fan 1 adopts a variable frequency regulation fan and is provided with an adjustable damper for adjusting the flue gas air inlet amount of the oxidation reactor 2.

[0021] In addition, the oxidation auxiliary agent inlet 207 of the oxidation reactor 2 can be connected with external oxidation auxiliary agent supply equipment, such as a storage tank and a pumping pipeline, and the oxidation auxiliary agent is generally hydrogen peroxide, ozone, waste sulfuric acid and the like.

[0022] In order to make the desulfurization ash contact with flue gas more fully and the temperature more uniform, a stirring device can be arranged in the oxidation reactor 2, and the specific arrangement can refer to Figure 2The stirring motor is fixed at the upper end of the oxidation reactor 2, the stirring shaft passes through the outer wall, and the stirring head is suspended inside the oxidation reactor 2. Other conventional stirring methods can also be used.

[0023] To achieve more precise control of the system, flow meters and control valves can be installed at the feed inlet 201, air inlet 203, water inlet 206, and oxidation aid inlet 207 of the oxidation reactor 2 to adjust the flow rate.

[0024] For reference, the above-mentioned treatment system's operation process and principle are as follows: Desulfurization ash from the desulfurization ash discharge port of the semi-dry desulfurization system (generally the ash discharge port of the bag filter) enters the oxidation reactor 2 through the feed inlet 201, and mixes with water sprayed in through the water inlet 206 to prepare a desulfurization ash slurry with a concentration of 5-30%; oxidation blower 1 draws a stream of flue gas from the front of the semi-dry desulfurization absorption tower, and enters the oxidation reactor 2 through the air inlet 203. The operating frequency and damper opening of oxidation blower 1 are adjusted to ensure that the flue gas volume meets the requirements to maintain the slurry oxidation temperature range of 70-90℃. SO2 in the flue gas reacts with Ca(OH)2 in the desulfurization ash slurry to generate CaSO4 and CaSO3, while oxygen in the flue gas desulfurizes the ash. The CaSO3 in the sulfur ash slurry is oxidized to CaSO4. During the oxidation process, water is added through water inlet 206 to maintain the slurry concentration, and an oxidation aid is added through oxidation aid inlet 207 to control the oxidation time. After the desulfurized ash slurry is oxidized, the water inlet 206 and oxidation aid inlet 207 valves are closed, the operating frequency of the oxidation fan 1 is increased, and the amount of flue gas introduced is increased to dry the desulfurized ash slurry to a dry powder state. The dried flue gas enters the dust collector 3 through the oxidation reactor 2, and the desulfurized ash carried by it is collected by the dust collector 3 and returned to the oxidation reactor 2. After oxidation and drying, the dry powder desulfurized ash is collected in the desulfurized ash silo 5 through the discharge port 202 of the oxidation reactor 2 and the ash unloading device 4.

[0025] Among them, such as Figure 1 As shown, the ash discharge device 4 can be a screw conveyor, etc. The discharge port 202 should usually be equipped with a switch valve. To prevent blockage, a pipeline crusher can also be installed in the pipeline connected to the ash discharge device 4.

[0026] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the scope of protection of this utility model. Therefore, the scope of protection of this utility model should be determined by the scope defined in the claims.

[0027] Any aspects of this utility model not described in detail are known to those skilled in the art.

Claims

1. A semi-dry desulfurization ash online disposal system, characterized in that: The oxidation fan (1), the oxidation reactor (2) and the dust remover (3) are connected, the inlet of the oxidation fan (1) is connected with the flue before the semi-dry desulfurization tower, the outlet of the dust remover (3) is connected with the inlet section of the semi-dry desulfurization tower, the oxidation reactor (2) is provided with a feeding port (201), a discharging port (202), an air inlet (203), an air outlet (204), a return port (205), a water inlet (206) and an oxidation additive inlet (207), the feeding port (201) of the oxidation reactor (2) is connected with the desulfurized ash discharging port of the semi-dry desulfurization system, the discharging port (202) is communicated to the desulfurized ash storage (5) through the ash discharging device (4), the air inlet (203) is connected with the outlet of the oxidation fan (1), the air outlet (204) is connected with the inlet of the dust remover (3), and the return port (205) is connected with the ash discharging port of the dust remover (3).

2. A semi-dry desulfurization ash online disposal system according to claim 1, characterized in that: The oxidation fan (1) is a variable frequency regulation fan and is provided with an adjustable damper.

3. A semi-dry desulfurization ash online disposal system according to claim 1, characterized in that: The oxidation additive inlet (207) of the oxidation reactor (2) is connected with an external oxidation additive supply device.

4. The semi-dry desulfurization ash online disposal system according to claim 1, characterized in that: The oxidation reactor (2) is internally provided with a stirring device.

5. A semi-dry desulfurization ash online disposal system according to claim 1, characterized in that: The feeding port (201), the air inlet (203), the water inlet (206) and the oxidation additive inlet (207) of the oxidation reactor (2) are all provided with flow metering instruments and control valves.

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