KR100287286B1 - System and method for removing dust and desulfurizing of flue gas during steelmaking and combustion of bunker-c oil - Google Patents

Abstract

PURPOSE: System and method are provided to exhaust air in the clean state by removing dust and sulfur oxides in the flue gas during steelmaking and combustion of bunker-C oil, and recycles the used cleaning water after water treatment. CONSTITUTION: The system for removing dust and desulfurizing of flue gas during steelmaking and combustion of bunker-C oil comprises a collection unit(10) collecting and removing dust of a large particle from a contaminant generation source; a cooling unit(20) on which a plurality of spray nozzles are arranged to rapidly cool the flue gas having a high temperature passing through the collection unit(10); a dust removal and desulfurizing unit(30) equipped with a filling material(30a), a spray nozzle(30b), an eliminator(30c) and demister(30d); a reservoir(40) supplying clean water with the spray nozzle(30b) and an eliminator(30c) of the dust removal and desulfurizing unit(30); a neutralizer storage tank(50) in which a neutralizer is stored to increase a hydrogen ion concentration of the clean water contained in the reservoir(40) so as to supply the neutralizer into the reservoir(40); an oxidation unit(60) oxidizing sulfite magnesium remained in waste water with magnesium sulfate by forcibly receiving oxygen from the outer part, and recirculating the clean water into the reservoir(40) by separating sludge from water; a cooling tower(70) cooling wastewater generated after the clean water of the reservoir(40) is circulated into the dust removal and desulfurizing unit(30); a purification unit(80) neutralizing wastewater by receiving wastewater from the oxidation unit(60) and receiving the neutralizer from the neutralizer storage tank(50); and a dehydration unit(90) caking the sludge by lowering a moisture content of a concentrate sludge after receiving the concentrated sludge from the oxidation unit(60).

Description

Facilities and methods for dust removal and desulfurization of flue gas during steel production and bunker seed oil combustion

The present invention relates to a facility for dust removal and desulfurization of flue gas during steel production and bunker seed oil combustion, and more particularly, to dust and sulfur oxides in flue gas emitted during steelmaking, steelmaking and bunker seed oil combustion. The present invention relates to a method and a method for dust removal and desulfurization of exhaust gas during steel production and bunker seed oil combustion which removes and releases the air as clean air and reuses the washing water used after treatment.

In steelmaking and steelmaking facilities, which typically use coal or bunker seed oil as fuel, and in other industries fueled by bunker seed oil, flue gases emitted after combustion contain large amounts of sulfur oxides together with dust. If the exhaust gas containing dust and sulfur oxides is discharged to the atmosphere as it is, it will not be a big problem in the reality that environmental regulations are being strengthened.

Therefore, the steelmaking and steelmaking facilities, and the equipment using bunker seed oil are essentially provided with a dust collector and a desulfurization device, so that the dust is collected and treated in the dust collector, and sulfur oxides are treated in the desulfurization device. Purify the exhaust gas.

However, the dust collector and the desulfurization apparatus which are conventionally provided in a facility using steelmaking and steelmaking facilities and bunker seed oil merely perform a fractional function of dust collection and desulfurization, and clean the exhaust gas, and The organic system of reuse after water treatment of the used washing water has not been proposed, and thus problems that cannot be satisfied with more preferable dust removal and desulfurization and related environmental problems have emerged.

The present invention has been made to solve the problems described above, and removes dust and sulfur oxides in the exhaust gas generated during the combustion of steelmaking, steelmaking and bunker seed oil to be discharged as clean air, It is an object of the present invention to provide a method and method for dedusting and desulfurizing flue gas during the production of steel and burning bunker seed oil with an organic system to reuse the water after water treatment.

Facilities for dust removal and desulfurization of flue gas during steel production and bunker seed oil combustion according to the present invention for achieving the above object, and a dust collecting device for collecting and removing large particles of dust from the pollutant source; A cooling device in which a plurality of spray nozzles are arranged to quench the high-temperature exhaust gas passing through the dust collector by a blowing fan; Filling layer to dampen and desulfurize the humidified flue gas quenched and introduced by this cooling device, spray nozzle for spraying washing water between the packed layer, and fine contaminants in the humid flue gas are collected by thick water droplets. A dust removal and desulfurization apparatus equipped with an eliminator for dropping, a demister for removing water in an atomized state passing through the eliminator and extremely fine dust or sulfur oxides; A water collecting tank for supplying washing water to the spray nozzle and eliminator of the dust removal and desulfurization apparatus; A neutralizing agent storage tank for supplying neutralizing agents to the water collecting tank by storing a neutralizing agent for increasing the hydrogen ion concentration of the washing water contained in the water collecting tank; An oxidation apparatus for oxidizing magnesium sulfite contained in the washing water of the sump to magnesium sulfate having excellent solubility; A cooling tower for cooling the wastewater generated by circulating the dust removal and desulfurization apparatus in the water collecting tank; The wastewater is supplied from the oxidizer, the neutralizer is supplied from the neutralizer storage tank to purify the wastewater, the oxygen is blown into the oxidizer by bleeding the magnesium sulfite remaining in the wastewater into magnesium sulfate, and the sludge is separated from the water. A water purification device for separating and recirculating clean water to the sump tank; It is characterized by comprising a dewatering device for feeding the sludge from the water purification device to lower the water content of the concentrated sludge to cake the sludge.

In addition, the method for dust removal and desulfurization of flue gas during steel production and bunker seed oil combustion according to the present invention comprises the steps of: first collecting and removing dust of large particles contained in the flue gas; Quenching the exhaust gas with cooling water to produce a humid exhaust gas; Dehumidification and desulfurization by passing through the filling layer while injecting the neutralized washing water into the humidified flue gas as a neutralizing agent. Or sulfur oxides are collected and removed with a demister to purify the exhaust gas; Cooling the wastewater generated by the purification of the exhaust gas; Neutralizing the cooled wastewater, blowing oxygen to oxidize magnesium sulfite in the wastewater to magnesium sulfate, separating the sludge from the water to purify the wastewater, and recycling the clean water; It characterized by consisting of the step of lowering the water content of the sludge to cake the sludge.

1 is a view showing a facility for dust removal and desulfurization of exhaust gas according to the present invention,

Explanation of symbols on the main parts of the drawings

10: dust collecting device 20: cooling device

30: dust removal and desulfurization device 40: water collection tank

50: neutralizer storage tank 60: oxidizer

70: cooling tower 80: water purifier

90: dewatering device

Hereinafter, the preferred embodiment of the present invention will be described in detail.

1 is a view showing the equipment for dust removal and desulfurization of the exhaust gas according to the present invention, as shown, the equipment for dust removal and desulfurization of the exhaust gas during the production of steel and combustion of bunker seed oil according to the present invention, contaminants A dust collecting device 10 for collecting and removing large particles of dust from the source; A cooling device 20 in which a plurality of spray nozzles 20a are disposed to quench the high-temperature exhaust gas passing through the dust collector 10 by quenching the fan 11; Filling layer 30a for dedusting and desulfurizing the humid exhaust gas quenched by the cooling device 20 and spray nozzle 30b for spraying the washing water between the filling layer 30a and humid An eliminator (30c) that collects and drips fine contaminants in the exhaust gas into coarse droplets, and a demister (30d) that removes water in the sprayed state and extremely fine dust or sulfur oxides passing through the eliminator (30c). Is provided with a vibration suppression and desulfurization device (30); A water collecting tank 40 having a water supply pump 41 for supplying washing water to the spray nozzle 30b and the eliminator 30c of the vibration suppression and desulfurization apparatus 30; A neutralizing agent storage tank 50 for supplying neutralizing agents to the water collecting tank 40 by a pump 51 by storing a neutralizing agent for increasing the hydrogen ion concentration of the washing water contained in the water collecting tank 40; An oxidizer 60 forcibly drawing oxygen from the outside through the blower 61 to oxidize magnesium sulfite remaining in the waste water to magnesium sulfate, separating sludge from water, and recycling clean water to the sump 40; A cooling tower (70) for cooling the waste water generated by circulating the dust removal and desulfurization apparatus (30) of the water collecting tank (40) by being transferred to a pump (42); A water purifier (80) for supplying wastewater from the oxidizer (60) through a pump (62) and receiving a neutralizer from the neutralizer storage tank (50) to purify the wastewater; The dehydration apparatus 90 receives the concentrated sludge by the pump 63 from the oxidizer 60 and lowers the water content of the concentrated sludge to cake the sludge.

Here, the cooling device 20 has a spray nozzle 20a for cooling the exhaust gas containing sulfur oxides at a high temperature of about 200 to 250 ° C. to 60 ° C. or less and spraying washing water to make sulfuric acid. As a full cone type, which is provided in five stages of about six in the circumferential direction of 20, it can evenly spray the washing water in multiple directions within the spraying radius and the nozzle is not blocked by fine foreign matter. The material is made of Teflon which can prevent corrosion by acid.

In addition, the dust removal and desulfurization apparatus 30 has a structure in which the filling layer 30a having a good contact efficiency between the gas and the liquid is arranged up and down so as to collect dust, and in each section of the filling layer 30a. A plurality of spray nozzles 30b are mounted, and an eliminator 30c having a zigzag shape is disposed above the filler layer 30a at the uppermost end so as to extend a path up and down, and above the eliminator 30c. The demister 30d which laminated | stacked several layers of mesh polypropylenes is arrange | positioned.

In addition, the neutralizing agent to be stored and used in the neutralizing agent storage tank 50 is made of seawater magnesium hydroxide (Mg (OH) ₂ ) which can prevent the secondary sludge generation due to the use of the neutralizing agent.

In addition, the oxidizer 60 has a structure in which an acid pipe formed with a plurality of fine holes in the water in order to maximize the contact between air and water, the water purifier 80 is for removing activated carbon and dust therein It has a structure in which a filter is installed.

Referring to the operation of the facility for dust removal and desulfurization of the exhaust gas during steel production and bunker seed oil combustion according to the present invention made as follows.

First, the dust collector 10 collects and drops coarse dust particles in the dust included in the exhaust gas discharged from the pollutant generating source, and the high temperature exhaust gas containing the fine dust is cooled by using the blower fan 11. Transfer to (20).

In addition, the cooling device 20 is a washing water sprayed through the spray nozzle 20a to quench the exhaust gas containing sulfur oxide (SO ₂ ) at a temperature of about 200 to 250 ° C. to 60 ° C. or less, and remove sulfur components. Change to sulfuric acid (SO ₂ + H ₂ O → H ₂ SO ₃ )

In addition, the vibration suppression and desulfurization apparatus 30 performs dust removal and desulfurization by the washing water injected from the filling layer 30a and the spray nozzle 30b with respect to the exhaust gas quenched by the cooling apparatus 20, and elimine Small droplets containing fine dust are collected and dropped into the coarse droplets from the emitter 30c, and the sprayed water passing through the eliminator 30c and the extremely fine dust or sulfur oxides are removed from the demister 30d. do.

In addition, the water collection tank 40 receives neutralizing agent, that is, magnesium hydroxide, stored in the neutralizing agent storage tank 50 as neutral washing water to the spray nozzle 30b and the eliminator 30c of the dust removal and desulfurization apparatus 30. (Mg (HSO ₃ ) + Mg (OH) ₂ → 2MgSO ₃ + 2H ₂ O)

In addition, the oxidizer 60 is forcibly blown oxygen to oxidize the magnesium sulfite (MgSO ₃ ) remaining in the waste water to magnesium sulfate (MgSO ₄ ) (MgSO ₃ + 1 / 2O ₂ → MgSO ₄ ), the sludge and water By separating, the clean water is recycled to the sump 40.

In addition, the cooling tower 70 circulates the dust removal and desulfurization apparatus 30 to cool the wastewater containing dust and sulfur components.

In addition, the water purifier 80 neutralizes the wastewater by adding the neutralizer supplied from the neutralizer storage tank 50 to the wastewater supplied from the oxidizer 60.

In addition, the dewatering device 90 dehydrates and dries the sludge separated from the water in the water purifying device 80 in a concentrated state to remove moisture and cakes.

On the other hand, the method for dust removal and desulfurization of the flue gas during steel manufacturing and bunker seed oil combustion according to the present invention comprises the steps of: collecting and removing dust of large particles contained in the flue gas primarily by using a dust collector; Quenching the exhaust gas with the cooling water injected through the spray nozzle using the cooling device to produce a humid exhaust gas; Using a dedusting and desulfurization device equipped with a filling layer, a spray nozzle, an eliminator and a demister, dehumidifying and desulfurizing by passing the cleaning water neutralized with a neutralizing agent through humidifying flue gas through the spray nozzle, Fine contaminants in the humid flue gas are dropped into coarse droplets as an eliminator, and the water in the sprayed state and extremely fine dust or sulfur oxides are collected by a demister to purify the flue gas; Cooling the wastewater generated by the purification of the exhaust gas using a cooling tower; Neutralizing the cooled wastewater with a neutralizer using an oxidizer and a purifier, blowing oxygen to oxidize magnesium sulfite into magnesium sulfate, separating sludge from water, and purifying the wastewater to recycle clean water; ; The dewatering device consists of lowering the water content of the sludge to cake the sludge.

Each step described above is replaced with the description of the configuration and operation of the facility for dust removal and desulfurization of the exhaust gas during the manufacturing and bunker seed oil combustion according to the present invention described above.

As described above, according to the present invention and a method for dust removal and desulfurization of the exhaust gas during the production of steel and bunker seed oil according to the present invention, by removing dust and sulfur oxides in the exhaust gas generated during steelmaking and steelmaking Emitted as a clean air, and can be reused after the water treatment at this time, it has the effect of doing a good job of environmental conservation.

Claims (4)

A dust collecting device 10 for collecting and removing large particles of dust from the pollutant generating source; A cooling device 20 in which a plurality of spray nozzles 20a are disposed to quench and receive the high-temperature exhaust gas passed through the dust collector 10; A filling layer 30a for dedusting and desulfurizing the humidified exhaust gas quenched by the cooling device 20 and a spray nozzle 30b for spraying washing water between the filling layer 30a; An eliminator (30c) that collects and drops fine contaminants in humid exhaust gas with coarse droplets, and a demister (removal of sprayed water and extremely fine dust or sulfur oxides) passing through the eliminator (30c). A dust removal and desulfurization apparatus 30 provided with 30d; A water collecting tank 40 for supplying washing water to the spray nozzle 30b and the eliminator 30c of the vibration removing and desulfurization apparatus 30; A neutralizer storage tank 50 for supplying a neutralizer to the water collection tank 40 by storing a neutralizing agent for increasing the hydrogen ion concentration of the washing water contained in the water collection tank 40; An oxidizer 60 forcibly drawing oxygen from the outside to oxidize magnesium sulfite remaining in the waste water into magnesium sulfate, separating sludge from water, and recycling clean water to the sump 40; A cooling tower (70) for cooling the waste water generated by circulating the dust removal and desulfurization apparatus (30) of the washing water of the water collecting tank (40); A water purifier (80) for supplying wastewater from the oxidizer (60) and receiving a neutralizer from the neutralizer storage tank (50) to neutralize the wastewater; Equipment for dust removal and desulfurization of the exhaust gas during bunker-seed oil combustion and consisting of a dewatering device (90) for feeding the sludge from the oxidizing device (60) to lower the water content of the concentrated sludge to cake the sludge. The method of claim 1, wherein the filling layer (30a) of the dust removal and desulfurization device 30 is arranged in a multi-layered up and down, a plurality of spray nozzles (30b) are mounted in the section of each of the filling layer (30a), The uppermost eliminator 30c is zigzag-shaped so as to extend the path up and down, and is disposed above the uppermost filling layer 30a, and the demister 30d is formed by stacking multiple layers of mesh polypropylene. And an apparatus for dust removal and desulfurization of exhaust gases during steel production and bunker seed oil combustion, which is disposed above the eliminator. The apparatus for dust removal and desulfurization of exhaust gas during steel production and bunker seed oil combustion according to claim 1, wherein the neutralizing agent used in the neutralization storage tank (50) is seawater magnesium hydroxide. Collecting and removing the large particles of dust contained in the flue gas firstly; Quenching the exhaust gas with cooling water to produce a humid exhaust gas; Dehumidification and desulfurization through the filling layer while injecting the neutralized washing water into the humidified flue gas as a neutralizing agent. Or sulfur oxides are collected and removed with a demister to purify the exhaust gas; Cooling the wastewater generated by the purification of the exhaust gas; Neutralizing the cooled wastewater, blowing oxygen to oxidize magnesium sulfite in the wastewater to magnesium sulfate, separating the sludge from the water to purify the wastewater, and recycling the clean water; A method for dedusting and desulfurization of flue-gas during steelmaking and bunker seed oil combustion, comprising the step of lowering the water content of the sludge to cake the sludge.