Resource utilization system for calcium-based ultrafine powder desulfurization by-products

Abstract

The invention discloses a calcium-based ultrafine powder desulfurization by-product resource utilization system. Comprising a storage system and a slurry preparation system, wherein the storage system comprises a storage bin body (2) and a bag type dust collector (3); the upper part of the storage bin body (2) is connected with the feeding device (1); the slurry preparation system comprises a slurry preparation tank (9), a slurry tank (15) and a clarification tank (19); the slurry preparation tank (9) is connected with a slurry tank (15) through a slurry transfer pump (13) and a filtering device (14); the slurry preparation tank (9) is connected with a clarification tank (19) through a communication device (18); the lower part of the storage bin body (2) is connected with a slurry preparation pool (9) through a pipeline; a manual gate valve (7) and a conveying and metering device (8) are arranged on a connecting pipeline between the storage bin body (2) and the slurry preparation pool (9). According to the invention, the calcium-based ultrafine powder desulfurization by-product and wet desulfurization are cooperatively treated, so that waste is turned into wealth.

Description

Technical Field

[0001] The invention relates to the technical field of resource utilization of flue gas desulfurization by-products, and in particular to a calcium-based ultrafine powder desulfurization by-product resource utilization system. Background Art

[0002] The calcium-based ultrafine powder desulfurization process is widely used in low-sulfur flue gases such as coke ovens, steel rolling heating furnaces, blast furnace hot blast furnaces, and gas boilers because of its wide source of raw materials, simple process flow, small one-time investment, simple maintenance, and desulfurization by-products that are slightly soluble in water and easy to store.

[0003] The main component of calcium-based ultrafine powder is Ca(OH)2. Its chemical properties and direct injection desulfurization method determine its Ca / S ratio. Due to the low utilization rate of the desulfurizer, excessive desulfurizer is often injected during the desulfurization process to ensure the desulfurization efficiency.

[0004] The composition of calcium-based ultrafine powder desulfurization varies according to the nature of the flue gas being treated, with CaSO4 and CaSO3 accounting for 30-35%, unreacted Ca(OH)2 and CaCO3 generated by the reaction with flue gas accounting for 45-55%. Other components account for about 10% (CaCl2, CaF2, Fe, Al oxides and sodium salts).

[0005] The composition and purity of the by-product cannot meet the requirements of the cement industry for industrial by-product gypsum and cement admixtures. Currently, this by-product is mostly treated in the form of backfilling or stacking.

[0006] In the flue gas desulfurization process with high concentration of SO2, the calcium-based wet desulfurization process has always been dominant. Its desulfurizer uses CaCO3 suspension or Ca(OH)2 suspension. Through a series of processes such as oxidation and dehydration, the by-product of this process is industrial gypsum with high purity, which meets the requirements of industrial by-product gypsum in the building materials industry. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a calcium-based ultrafine powder desulfurization by-product resource utilization system. After pretreatment of the calcium-based ultrafine powder desulfurization by-product, it can be directly used in a calcium-based wet desulfurization system. Through coordinated treatment with the wet desulfurization system, the calcium-based ultrafine powder desulfurization by-product can be effectively treated and turned into treasure.

[0008] The technical solution of the present invention is: a calcium-based ultrafine powder desulfurization by-product resource utilization system, including a storage system and a slurry preparation system, the storage system includes a storage bin body and a bag dust collector, the bag dust collector is arranged on the upper part of the storage bin body; the upper part of the storage bin body is connected to a feeding device; the slurry preparation system includes a slurry preparation tank, a slurry tank, and a clarification tank; the slurry preparation tank is connected to the slurry tank through a slurry transfer pump and a filtering device; the slurry preparation tank is connected to the clarification tank through a connecting device; the clarification tank is connected to the slurry preparation tank or the sewage treatment system through a filtrate pump; the lower part of the storage bin body is connected to the slurry preparation tank through a pipeline; a manual gate valve and a conveying metering device are arranged on the connecting pipeline between the storage bin body and the slurry preparation tank.

[0009] Furthermore, a pressure reducing device and a material level measuring device are provided on the upper part of the storage bin body.

[0010] Furthermore, the storage bin body has a fluidizing device at the bottom.

[0011] Furthermore, the slurry preparation tank comprises a stirring device, a slag discharge device, and a liquid level measuring device; an electric valve is arranged on the pipeline connecting the filtrate pump to the slurry preparation tank, and the electric valve and the liquid level measuring device are interlocked with the conveying metering device.

[0012] Furthermore, the slurry pool comprises a filtering device and a stirring device, and the slurry pool is connected to a slurry delivery pump, and the slurry is delivered to the wet flue gas desulfurization system through the slurry delivery pump.

[0013] Furthermore, an air blocking device is provided on the connecting pipeline between the conveying and metering device and the slurry preparation tank.

[0014] Furthermore, the slurry transfer pump, slurry delivery pump and filtrate pump are submersible pumps or horizontal centrifugal pumps.

[0015] Furthermore, the feeding device is a pneumatic conveying device or a mechanical feeding device.

[0016] Furthermore, the conveying and metering device is a double-tube screw scale.

[0017] Furthermore, the slag discharge device adopts a double-tube spiral and is equipped with a flushing device.

[0018] This system includes a series of processes such as metering, pulping, slag discharge, filtration, and clarification: the calcium-based ultrafine powder desulfurization byproducts and process water or filtrate water enter the pulping tank in proportion, and slurries with different mass concentrations and components are generated in the pulping tank under the action of the agitator. Qualified slurries are extracted by separate treatment of slurries of different layers. The bottom insoluble matter is discharged through the slag discharger, the middle layer suspension is sent to the slurry tank through the transfer pump and the filtration device, and the surface clear liquid overflows to the clarification tank for natural precipitation. The slurry in the slurry tank can be transported to the wet flue gas desulfurization tower by the slurry pump for adjusting the pH value, and the clear liquid in the clarification tank can be transported to the pulping tank for reuse by the filtrate pump. According to the concentration of Cl ions in the filtrate, it can also be sent to the wastewater treatment system in the wet flue gas desulfurization process.

[0019] The beneficial technical effects of the present invention are: the calcium-based ultrafine powder desulfurization by-products are synergistically treated with wet desulfurization to turn waste into treasure; through the combined arrangement of a slurry preparation tank, a slurry tank and a clarification tank, the functional areas of desulfurization by-product washing, slag discharge, pulping and slag discharge are brought together to reduce the floor space; the stratified properties of the calcium-based ultrafine powder desulfurization by-product slurry are utilized to solve the problems of complex processes and numerous equipment in the desulfurization by-product treatment project by stratifying the suspension; and the synergistic treatment of pulping, oxidation, dehydration and wastewater with the calcium-based wet desulfurization system solves the problem of wastewater treatment in the by-product treatment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural diagram of a calcium-based ultrafine powder desulfurization by-product resource utilization system.

[0021] In the figure: 1-feeding device, 2-storage silo body, 3-bag dust collector, 4-pressure reducing device, 5-level measuring device, 6-fluidizing device, 7-manual plug valve, 8-transporting metering device, 9-slurry preparation tank, 10-preparation tank agitator, 11-slag discharge device, 12-level meter, 13-slurry transfer pump, 14-filtration device, 15-slurry tank, 16-slurry tank agitator, 17-slurry delivery pump, 18-connecting device, 19-clarification tank, 20-filtrate pump, 21-electric valve, 22-flow meter. DETAILED DESCRIPTION

[0022] In order to make the purpose and technical solution of the present invention more clearly understood, the present invention is further described below in conjunction with a system structure diagram and embodiments.

[0023] The desulfurization by-product is a calcium-based ultrafine powder desulfurization product, the raw material of which is calcium-based ultrafine powder, and is mainly used in the low-sulfur flue gas desulfurization process.

[0024] The main components of the desulfurization by-products are Ca(OH)2, CaCO3, CaSO4 and CaSO3, and the mass ratio of the above main calcium-based compounds is not less than 85-90%.

[0025] like Figure 1 A calcium-based ultrafine powder desulfurization by-product resource utilization system includes a storage system and a slurry preparation system. The storage system includes a storage bin body 2 and a bag dust collector 3, and the bag dust collector 3 is arranged on the upper part of the storage bin body 2; the upper part of the storage bin body 2 is connected to a feeding device 1; the slurry preparation system includes a slurry preparation tank 9, a slurry tank 15, and a clarification tank 19; the slurry preparation tank 9 is connected to the slurry tank 15 through a slurry transfer pump 13 and a filtering device 14; the slurry preparation tank 9 is connected to the clarification tank 19 through a connecting device 18; the clarification tank 19 is connected to the slurry preparation tank 9 or a sewage treatment system through a filtrate pump 20; the lower part of the storage bin body 2 is connected to the slurry preparation tank 9 through a pipeline; a manual gate valve 7 and a conveying metering device 8 are arranged on the connecting pipeline between the storage bin body 2 and the slurry preparation tank 9.

[0026] A pressure reducing device 4 and a material level measuring device 5 are arranged on the upper part of the storage bin body 2 .

[0027] A fluidizing device 6 is disposed at the lower part of the storage bin body 2, and the fluidizing device 6 ensures smooth material discharge.

[0028] The slurry preparation tank 9 includes a stirring device 10, a slag discharge device 11, and a liquid level measuring device 12; an electric valve 21 and a flow meter 22 are arranged on the pipeline connecting the filtrate pump 20 to the slurry preparation tank 9, and the electric valve 21 and the liquid level measuring device 12 are interlocked with the conveying metering device 8.

[0029] The slurry pool 15 comprises a filtering device 14 and a stirring device 16 . The slurry pool 15 is connected to a slurry delivery pump 17 , and the slurry is delivered to the wet flue gas desulfurization system through the slurry delivery pump 17 .

[0030] An air blocking device is provided on the connecting pipeline between the conveying and metering device 8 and the slurry preparation pool 9 to prevent water vapor in the slurry preparation pool 9 from entering the conveying and metering device 8 .

[0031] The slurry transfer pump 13, the slurry delivery pump 17, and the filtrate pump 20 are submersible pumps or horizontal centrifugal pumps.

[0032] The feeding device 1 is a pneumatic conveying device or a mechanical feeding device.

[0033] The conveying metering device 8 is a double-tube spiral scale, the upper spiral is designed to lock the air and material to prevent the calcium-based ultrafine powder desulfurization by-product from rushing into the material; the lower spiral is provided with a metering device to measure the discharge amount of the calcium-based ultrafine powder desulfurization by-product.

[0034] The slurry preparation tank 9 is provided with a liquid level meter 12.

[0035] The slag discharge device 11 adopts a double-tube spiral and is equipped with a flushing device.

[0036] The above patent is described in detail in conjunction with the drawings and embodiments, but the patent is not limited to the above-mentioned specific implementation methods. The above-mentioned specific embodiments are merely illustrative and not restrictive. Under the inspiration of this patent, technicians in this field can also make many forms without departing from the purpose of this patent and the scope of protection of the claims, all of which are protected by this patent.

Claims

1. A calcium-based ultrafine powder desulfurization by-product resource utilization system, characterized by The invention comprises a storage system and a slurry preparation system. The storage system comprises a storage bin body (2) and a bag dust collector (3). The bag dust collector (3) is arranged on the upper part of the storage bin body (2); the upper part of the storage bin body (2) is connected to a feeding device (1); the slurry preparation system comprises a slurry preparation tank (9), a slurry tank (15), and a clarification tank (19); the slurry preparation tank (9) is connected to the slurry tank (15) through a slurry transfer pump (13) and a filtering device (14); the slurry preparation tank (9) is connected to the clarification tank (19) through a connecting device (18); the clarification tank (19) is connected to the slurry preparation tank (9) or a sewage treatment system through a filtrate pump (20); the lower part of the storage bin body (2) is connected to the slurry preparation tank (9) through a pipeline; a manual gate valve (7) and a conveying metering device (8) are arranged on the connecting pipeline between the storage bin body (2) and the slurry preparation tank (9).

2. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1 is characterized by: A pressure reducing device (4) and a material level measuring device (5) are provided on the upper part of the storage bin body (2).

3. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1 is characterized by: A fluidizing device (6) is provided at the lower part of the storage bin body (2).

4. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1 is characterized by: The slurry preparation tank (9) comprises a stirring device (10), a slag discharge device (11), and a liquid level measuring device (12); an electric valve (21) is arranged on a pipeline connecting the filtrate pump (20) to the slurry preparation tank (9); the electric valve (21) and the liquid level measuring device (12) are interlocked with a conveying metering device (8).

5. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1 is characterized by: The slurry pool (15) comprises a filtering device (14) and a stirring device (16). The slurry pool (15) is connected to a slurry delivery pump (17) and is delivered to a wet desulfurization system via the slurry delivery pump (17).

6. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1 is characterized by: The connecting pipeline between the conveying and metering device (8) and the slurry preparation tank (9) is provided with an air blocking device.

7. A calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1, 4 or 5, characterized in that: The slurry transfer pump (13), the slurry delivery pump (17), and the filtrate pump (20) are submersible pumps or horizontal centrifugal pumps.

8. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1 is characterized by: The feeding device (1) is a pneumatic conveying device or a mechanical feeding device.

9. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 1 is characterized by: The conveying and metering device (8) is a double-tube screw scale.

10. The calcium-based ultrafine powder desulfurization byproduct resource utilization system according to claim 4 is characterized by: The slag discharge device (11) adopts a double-tube spiral and is equipped with a flushing device.

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