CN110132020A - A comprehensive treatment device for electric furnace flue gas based on waste tire incineration - Google Patents

Abstract

The invention belongs to the field of industrial kiln flue gas utilization and treatment, and relates to a comprehensive treatment device for electric furnace flue gas based on the incineration of waste tires, which is used to recover the waste heat of the flue gas in the fourth hole of the electric furnace and treat pollutants in the flue gas, including waste steel pretreatment. heating device, flue gas bypass, waste heat boiler, desulfurization tower, powder injection device, bag dust collector and induced draft fan, etc.; the electric furnace flue gas is sprayed through the fourth hole of the electric furnace and divided into two paths, and one path enters the scrap steel preheating device for heating Scrap steel undergoes preliminary waste heat recovery, and the other way directly enters the waste heat boiler for waste heat recovery, and finally enters the desulfurization tower, and is discharged to the atmosphere through the induced draft fan after dust removal through the dust removal pipeline, powder injection device, and bag filter. The present invention comprehensively treats the electric furnace of waste tires added at present, not only can recover the waste heat in the flue gas, but also can jointly remove harmful substances such as sulfur dioxide and dioxin in the flue gas.

Description

A comprehensive treatment device for electric furnace flue gas based on waste tire incineration

technical field

The invention belongs to the field of industrial kiln flue gas utilization and treatment, and relates to an electric furnace flue gas comprehensive treatment device based on waste tire incineration.

Background technique

Electric furnace steel accounts for 30% of the world's total steel, and the proportion of electric furnace steel has been increasing in the past 20 years. In electric arc furnace steelmaking, electrical energy input accounts for 60-65% of the total energy, and chemical energy accounts for 35-40%. The chemical energy is mainly the result of the reaction of oxygen blowing to produce carbon and oxygen. For the sustainable development of electric furnaces, the way to reduce coal consumption is to try potential alternative fuels, and rubber tires and discarded plastic products are substitutes for coal. These are not only good substitutes for electric furnace steelmaking, but burning these substitutes , can also solve environmental problems.

However, the use of high molecular polymers such as waste tires instead of carbon powder will cause pollutants such as sulfides and dioxins in the flue gas to exceed the standard. Therefore, how to control the emission of flue gas pollutants and effectively use the flue gas Waste heat in waste tires has become a major problem in electric furnace flue gas treatment technology based on waste tires.

Contents of the invention

In view of this, the object of the present invention is to provide a comprehensive treatment device for electric furnace flue gas based on waste tire incineration, which is used to recover the waste heat of electric furnace flue gas and remove sulfur and other pollutants in the flue gas.

To achieve the above object, the present invention provides the following technical solutions:

An electric furnace flue gas comprehensive treatment device based on waste tire incineration, comprising an electric furnace body connected to a waste heat boiler through a scrap steel preheating device, connected to a dust collector through a desulfurization reaction tower, and discharged through a chimney.

Optionally, the scrap steel preheating device is connected with the electric furnace body through the fourth hole of the electric furnace.

Optionally, the fourth hole of the electric furnace is also connected with a flue gas bypass connected in parallel with the scrap steel preheating device.

Optionally, a flow regulating valve is arranged on the flue gas bypass.

Optionally, the dust collector includes a powder injection device and a bag dust collector arranged in sequence.

Optionally, a vibrating screening device is also included, the inlet of the powder injection device is connected to the outlet of the vibrating screening device, and the powder is transported from the vibrating screening device to the inlet of the powder injection device by compressed air.

Optionally, the powder injection device is a countercurrent injection.

Optionally, the inlet powder of the rotary nozzle is sodium carbonate or sodium bicarbonate.

Optionally, an induced draft fan is also provided between the dust collector and the chimney.

Optionally, the side of the waste heat boiler facing the scrap steel preheating device is a water-cooled membrane wall, and the side away from the scrap steel preheating device is a convective heat exchange surface.

Optionally, an ash hopper is provided at the bottom of the waste heat boiler.

Optionally, the convective heat exchange surface is vertically arranged and suspended on the top of the waste heat boiler.

Optionally, the desulfurization tower includes a flue gas equalization device disposed on the side of the desulfurization tower facing the waste heat boiler, a rotary nozzle and a Venturi nozzle disposed on the desulfurization tower.

Optionally, the number of Venturi nozzles is 8, arranged in an annular array.

Optionally, a combustion nozzle is provided in the scrap steel preheating device.

The beneficial effects of the present invention are:

The present invention can adjust the preheating temperature of the scrap steel by setting the scrap steel preheating device and the flue gas bypass, combined with the waste heat boiler can further deeply recover the waste heat of the flue gas, and improves the utilization rate of the waste heat of the flue gas. The present invention can also carry out dry desulfurization through the cooperation of the vibrating screening device and the powder spraying device, and remove pollutants such as dioxin in the flue gas, so as to ensure that the flue gas emission meets the standard.

Other advantages, objects and features of the present invention will be set forth in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the investigation and research below, or can be obtained from It is taught in the practice of the present invention. The objects and other advantages of the invention may be realized and attained by the following specification.

Description of drawings

In order to make the purpose of the present invention, technical solutions and advantages clearer, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

Figure 1 is a schematic diagram of the overall structure of the present invention.

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the diagrams provided in the following embodiments are only schematically illustrating the basic concept of the present invention, and the following embodiments and the features in the embodiments can be combined with each other in the case of no conflict.

Wherein, the accompanying drawings are for illustrative purposes only, and represent only schematic diagrams, rather than physical drawings, and should not be construed as limiting the present invention; in order to better illustrate the embodiments of the present invention, some parts of the accompanying drawings may be omitted, Enlargement or reduction does not represent the size of the actual product; for those skilled in the art, it is understandable that certain known structures and their descriptions in the drawings may be omitted.

In the drawings of the embodiments of the present invention, the same or similar symbols correspond to the same or similar components; , "front", "rear" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred devices or elements must It has a specific orientation, is constructed and operated in a specific orientation, so the terms describing the positional relationship in the drawings are for illustrative purposes only, and should not be construed as limiting the present invention. For those of ordinary skill in the art, the understanding of the specific meaning of the above terms.

Please refer to Figure 1, the component numbers in the accompanying drawings represent: electric furnace body 1, electric furnace fourth hole 2, scrap steel preheating device 3, flue gas bypass 4, waste heat boiler 5, desulfurization reaction tower 6, powder injection device 7, Bag filter 8, induced draft fan 9, chimney 10, vibrating screening device 11, flow regulating valve 12, combustion nozzle 13, water-cooled membrane wall 14, convective heat exchange surface 15, flue gas equalization device 16, rotating nozzle 17, Venturi nozzle 18.

The present invention relates to an electric furnace flue gas comprehensive treatment device based on waste tire incineration, comprising an electric furnace body 1, the electric furnace body 1 is connected to a waste heat boiler 5 through a scrap steel preheating device 3, and is connected to a dust collector through a desulfurization reaction tower 6, It is discharged through the chimney 10.

Optionally, the scrap steel preheating device 3 is connected to the electric furnace body 1 through the fourth hole 2 of the electric furnace; the fourth hole 2 of the electric furnace is also connected with a flue gas bypass 4 connected in parallel with the scrap steel preheating device 3; The flue gas bypass 4 is provided with a flow regulating valve 12 .

Specifically, the dust collector includes a powder injection device 7, a bag filter 8, and a vibratory screening device 11 arranged in sequence. The inlet of the powder injection device 7 is transported from the vibratory screening device 11; the powder injection device 7 is a countercurrent injection; the powder at the inlet of the rotary nozzle 17 is sodium carbonate or sodium bicarbonate; between the dust collector and the chimney 10 Also be provided with induced draft fan 9.

In this embodiment, the side of the waste heat boiler 5 facing the scrap steel preheating device 3 is a water-cooled membrane wall 14, and the side away from the scrap steel preheating device 3 is a convective heat exchange surface 15; There is an ash hopper; the convective heat exchange surface 15 is vertically arranged and suspended on the top of the waste heat boiler 5 .

Optionally, the desulfurization tower includes a flue gas equalizing device 16 arranged on the side of the desulfurization tower facing the waste heat boiler 5, a rotating nozzle 17 and a Venturi nozzle 18 arranged on the desulfurization tower; the number of the Venturi nozzles 18 is 8, arranged in an annular array; the scrap steel preheating device 3 is provided with a combustion nozzle 13 .

In the specific operation process, the flue gas smelted by the electric furnace body 1 enters the scrap steel preheating device 3 through the fourth hole 2 of the electric furnace. The flue gas from the preheating device 3 enters the waste heat boiler 5, and the front section of the waste heat boiler 5 is a radiant wide channel heat exchange surface (water-cooled membrane wall 14), where the unburned CO in the flue gas is burned and settle large particles of dust, and then enter the convective heat exchange surface 15 of the waste heat boiler 5 for further heat exchange and cooling to 150°C. There is an ash hopper at the bottom of the waste heat boiler 5, and the dust settled and accumulated in the waste heat boiler 5 is collected in the ash hopper.

It should be noted that a combustion nozzle 13 is provided at the bottom of the scrap steel preheating device 3. When the flue gas temperature is not enough during the non-smelting period of the electric furnace, the scrap steel is preheated through natural gas supplementary combustion to increase the scrap steel entering the electric furnace to reach the specified temperature, and at the same time control the temperature of the scrap steel The temperature of the flue gas at the outlet of the preheating device 3 is not lower than 800°C, which reduces the formation of dioxins at low temperatures and ensures the stable operation of the waste heat boiler 5 .

On the other hand, a flue gas bypass 4 is provided on the pipe connecting the fourth hole 2 of the electric furnace to the scrap steel preheating device 3, and a flue gas flow regulating valve 12 is arranged on it, and the waste steel preheating is distributed by controlling the flue gas flow regulating valve 12. Flue gas volume in unit 3. During the smelting period, the flue gas temperature of the fourth hole 2 of the electric furnace is high, so the flue gas flow rate of the scrap steel preheating device 3 is increased to improve the preheating effect; during the non-smelting period, the flue gas temperature of the fourth hole 2 of the electric furnace is low, and the scrap steel is reduced The flue gas flow rate of the preheating device 3 is enhanced by supplementary combustion of natural gas for preheating.

The cooled electric furnace flue gas enters the desulfurization tower. A flue gas equalization device 16 is installed at the entrance of the desulfurization tower. A rotating nozzle 17 is installed at the lower part of the desulfurization tower. After the flue gas is mixed with the sodium bicarbonate powder ejected from the rotating nozzle 17, it enters the The Venturi nozzle 18 in the middle of the desulfurization tower accelerates to form a turbulent state, fully reacts with the desulfurization agent in the upper part of the desulfurization tower, and then exits from the top of the desulfurization tower into the bag filter 8. There is a powder injection device 7 on the inlet pipe of the bag filter 8, and the activated carbon from the powder injection device 7 is sprayed into the flue gas in reverse, and the flue gas containing activated carbon enters the bag filter 8 and is collected and loaded on the bag-coated filter material Above, the dioxins in the flue gas are adsorbed and removed by the activated carbon and then enter the chimney 10 to meet the emission standards.

There is a vibrating screening device 11 under the ash hopper at the bottom of the bag filter 8. The collected activated carbon and desulfurization by-products are sent to the powder injection device 7 at the inlet of the bag filter 8 as circulating materials, and other electric furnace ash enters the residual material bin. transport.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements, without departing from the spirit and scope of the technical solution, should be included in the scope of the claims of the present invention.

Claims (10)

1. a kind of electric furnace flue gas Integrated Processing Unit burned based on waste tire, it is characterised in that: described including electric furnace ontology Electric furnace ontology is connected to waste heat boiler by scrap preheater, and is connected to deduster by desulfurization reaction tower, arranges through chimney Out.

2. the electric furnace flue gas Integrated Processing Unit burned as described in claim 1 based on waste tire, it is characterised in that: institute Scrap preheater is stated to be connected by the 4th hole of electric furnace with electric furnace ontology.

3. the electric furnace flue gas Integrated Processing Unit burned as described in claim 2 based on waste tire, it is characterised in that: institute It states the 4th hole of electric furnace and is also connected with the gas bypass in parallel with the scrap preheater.

4. the electric furnace flue gas Integrated Processing Unit burned as described in claim 1 based on waste tire, it is characterised in that: institute Stating deduster includes the pulvis injection apparatus and bag filter being sequentially arranged.

5. the electric furnace flue gas Integrated Processing Unit burned as described in claim 4 based on waste tire, it is characterised in that: also Including vibration screening device, the import of the pulvis injection apparatus is connected with vibration screening device outlet, and pulvis is empty by compression Gas is delivered to the import of pulvis injection apparatus from vibration screening device.

6. the electric furnace flue gas Integrated Processing Unit burned as described in claim 1 based on waste tire, it is characterised in that: institute It states and is additionally provided with air-introduced machine between deduster and chimney.

7. the electric furnace flue gas Integrated Processing Unit burned as described in claim 1 based on waste tire, it is characterised in that: institute It is water cooled membrane wall that waste heat boiler, which is stated, towards the side of scrap preheater, and the side far from scrap preheater is heat convection Face.

8. the electric furnace flue gas Integrated Processing Unit burned as described in claim 1 based on waste tire, it is characterised in that: institute Stating desulfurizing tower includes the flue gas flow equalizing device being arranged in desulfurizing tower towards waste heat boiler side, the rotation spray that is arranged on desulfurizing tower Mouth and Venturi nozzle.

9. the electric furnace flue gas Integrated Processing Unit burned as described in claim 8 based on waste tire, it is characterised in that: institute Stating Venturi nozzle quantity is 8, annular array arrangement.

10. the electric furnace flue gas Integrated Processing Unit burned as described in claim 1 based on waste tire, it is characterised in that: Burner noz(zle) is equipped in the scrap preheater.