KR101630223B1 - Oxygen enrichment system - Google Patents

Abstract

An oxygen enrichment system according to an embodiment of the present invention includes a lance for supplying fuel or oxygen; A burner connected to the lance and extending inside the kiln; And a control unit connected to the lance and the burner, respectively.
The oxygen enrichment system according to the embodiment of the present invention has an effect of improving the combustion efficiency by increasing the combustion efficiency in the rotary kiln by connecting the lance to the burner.

Description

OXYGEN ENRICHMENT SYSTEM

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to an oxygen-enriching system, and more particularly, to an oxygen-enriching system having improved combustion performance by reducing the amount of combustion air and the amount of exhaust gas.

Generally, in the case of a calcining furnace or a cement kiln furnace, a rotary kiln is generally used for the treatment of fine ores, and in order to supply a large amount of energy required for calcining ores in the kiln, Use coal and heavy oil burners.

At this time, air is mixed and burned at the front end of the burner as a combustion gas together with the fuel, so that the fuel is supplied so that firing of the ore can be easily performed while maintaining a uniform temperature in the furnace.

The structure of the rotary kiln used for firing ores is such that the burner 11 is horizontally positioned at the center of the firing furnace 10 as shown in FIG. 1, and the fuel and air are supplied to the burner 11, 10 to maintain the temperature at the ore firing temperature, and the ore 1 is moved to the bottom while being rotated at a constant speed in the kiln, and is fired.

At this time, the flue gas is discharged to the inlet of the ore compartment in the direction opposite to the moving direction of the ore and is heat-exchanged while passing through the ore preheater 14, and is then passed through the dust collecting device such as the cyclone 15 and the venturi scrubber 20, chimney: 100). Normally, when the kind of the ore and the production target amount are determined, the required heat amount is calculated, the required heat amount is calculated according to the heat amount of the fuel, and a certain amount of air is injected thereinto. At this time, the gas and the pulverized coal fuel form a flame at the front end of the burner.

At this time, in order to maintain the inside of the calcining furnace 10 at a high temperature atmosphere of 1,000 ° C or more, the shape of the flame is bent upward in the course of burning a large amount of fuel, and the heat transfer to the ore- It is not efficient and the firing of the product is not performed smoothly.

In order to secure the quality of the produced product, excess fuel is supplied in order to give sufficient heat for firing the ore. In this case, there is a problem that a large amount of nitrogen oxide is generated together with a local temperature rise due to the excess fuel.

Here, the quicklime, the light dolomite, and the cement product, which are the product products discharged after completing the firing in the rotary kiln firing furnace, have a high temperature of about 800 ° C. and are supplied to the cooling device 12 for storing the fired product before being taken out. Since air at room temperature is blown into the cooling device 12, the product product can be cooled to about 100 to 150 占 폚.

The product cooling air supplied to the rotary kiln through the product cooler forms the inside of the rotary kiln in an oxidizing atmosphere and the fuel that has not been completely burned by the primary combustion air supplied through the burner 11 As the oxidizing agent for completely burning the fuel.

Therefore, in the case of a rotary kiln in which a heat source is supplied using a gas or a solid fuel, the rotation of the rotary kiln 10 having a certain angle in the process of maintaining the internal temperature of the calcining furnace at a constant temperature of about 1000 ° C. Sufficient heat transfer to the ore sintered body moving to the position of the lower burner 11 can not be achieved.

Accordingly, a large amount of fuel must be supplied and burned. However, when a large amount of fuel is supplied for supplying sufficient energy, the flame temperature of the burner 11 becomes excessively high.

As a result, the flame shape is bent toward the upper wall and the melt of the low-melting-point fine-ore material floating in the furnace adheres to the wall of the furnace and grows. As a result, the flame- There is a problem in that it is necessary to frequently perform the removing operation.

Accordingly, conventionally, in the case of ore burning furnace, as the high production operation or high quality operation is pursued, the formation of deposits increases, and the inefficient operation of lowering the flame temperature by lowering the primary combustion air amount to the fuel cost has been performed , There is a problem that the sintering quality of the product deteriorates with the decrease of the productivity due to the decrease of the thermal efficiency.

Patent Document 1: JP-A-10-0577331

It is an object of the present invention to provide an oxygen-enriching system with improved combustion performance by reducing the amount of combustion air and the amount of exhaust gas.

An oxygen enrichment system according to an embodiment of the present invention includes a lance for supplying fuel or oxygen; A burner connected to the lance and extending inside the kiln; And a control unit connected to the lance and the burner, respectively.

In the oxygen enrichment system according to an embodiment of the present invention, the lance may include a tip portion having a plurality of injection paths inclined at a predetermined angle; A connection pipe connected to the distal end portion; And a stopper provided on the outer side of the connection pipe.

In an oxygen enrichment system according to an embodiment of the present invention, the lance has a tip with at least one injection passage having a diameter smaller than the inner diameter; A connection pipe connected to the distal end portion; And a stopper provided on the outer side of the connection pipe.

In the oxygen enrichment system according to the embodiment of the present invention, the lance may further include an outer pipe surrounding the outer surface of the connection pipe.

In an oxygen enrichment system according to an embodiment of the present invention, the burner comprises an outer housing tube; A plurality of circular tubes concentrically disposed in the outer housing tube; A lance connector to which the lance is connected at a rear center; An air inlet for injecting air into the rear side; And a fuel injection port for injecting fuel of pulverized coal or oil into the rear outer side.

In the oxygen enrichment system according to the embodiment of the present invention, the plurality of circular tubes include a first circular tube, a second circular tube, a third circular tube, a fourth circular tube and a central tube inwardly of the outer housing tube, (I) is formed between the first circular tube and the second circular tube, a second circular tube (II) is formed between the second circular tube and the third circular tube, and the third circular tube and the fourth circular tube A third flow path (III) is formed between the circular tubes, a fourth flow path (IV) is formed between the fourth circular tube and the center tube, and a fifth flow path (V) is formed inside the center tube .

The oxygen enrichment system according to the embodiment of the present invention further comprises a donut-shaped spray plate having a plurality of holes at a tip portion between the fourth circular tube and the center tube.

In the oxygen enrichment system according to the embodiment of the present invention, the control unit moves at least one of the second circular pipe, the third circular pipe and the fourth circular pipe backward.

In the oxygen enrichment system according to the embodiment of the present invention, the second cylindrical tube and the third cylindrical tube are formed in a thickened and inclined shape in the tip direction.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to this, terms and words used in the present specification and claims should not be construed in a conventional, dictionary sense, and should not be construed as defining the concept of a term appropriately in order to describe the inventor in his or her best way. It should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention.

The oxygen enrichment system according to the embodiment of the present invention has an effect of improving the combustion efficiency by increasing the combustion efficiency in the rotary kiln by connecting the lance to the burner.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exemplary view showing the construction of a general rotary kiln type firing furnace. Fig.
2 is an exemplary view for explaining an oxygen enrichment system according to an embodiment of the present invention;
Figure 3a is a side cross-sectional view of a lance making up the oxygen enrichment system in accordance with an embodiment of the present invention.
FIG. 3B is a front perspective front view of a lance constituting an oxygen enrichment system according to an embodiment of the present invention. FIG.
3c is a front perspective front view of a lance constituting an oxygen enrichment system according to another embodiment of the present invention;
4 is a cross-sectional view of a burner constituting an oxygen enrichment system according to an embodiment of the present invention;
5A is a front elevation view of a burner constituting the oxygen enrichment system according to the embodiment of the present invention.
5B is a front side view of the burner constituting the oxygen enrichment system according to the embodiment of the present invention.
FIG. 5C is a cross-sectional front view of the burner constituting the oxygen enrichment system according to the embodiment of the present invention; FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The objects, particular advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements have the same numerical numbers as much as possible even if they are displayed on different drawings. Also, the terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 3 is a cross-sectional side view of a lance constituting the oxygen enrichment system according to the embodiment of the present invention, and FIG. 3B is a side view of the oxygen enrichment system according to an embodiment of the present invention. FIG. 3C is a front perspective front view of a lance constituting the oxygen enrichment system according to another embodiment of the present invention, and FIG. 4 is a front perspective view of a lance constituting the oxygen enrichment system according to an example. Sectional view of a burner constituting the oxygen enrichment system.

The oxygen enrichment system according to an embodiment of the present invention will be described with reference to a form applied to a sintering process for producing cement as shown in FIG.

In detail, the oxygen enrichment system according to the embodiment of the present invention includes a preheating unit 300 including a calciner 314, a rotary kiln 10 which is a firing furnace for producing a cement crinker, and a rotary kiln 10 And a cement clinker cooler 400 disposed at an outlet of the cement clinker cooler 400. The cement clinker cooler 400 can be applied to a firing process for producing cement using waste and fuel.

In particular, the oxygen enrichment system according to an embodiment of the present invention includes a lance 100 for supplying fuel or oxygen, a burner 200 connected to the lance 100 and extending inside the rotary kiln 10, 100 and a control unit (not shown) connected to the burner 200. The amount of combustion air and the amount of exhaust gas can be reduced to improve the combustibility.

The lance 100 is a tubular member connected to a liquefied oxygen storage tank and connected to one side of the burner 200 to supply oxygen and has a tip portion 110 A connection pipe 120 connected to the distal end 110 and a stopper 140 provided on the outer side of the connection pipe 120 to support the connection pipe 120. The lance 100 optionally includes an outer tube 130 surrounding the outer surface of the connection pipe 120 so that the refrigerant flows into the space between the connection pipe 120 and the outer pipe 130, Heat exchange can be performed with respect to oxygen flowing in the exhaust gas.

The lance 100 may be selectively connected to the preheater 300, the inlet of the rotary kiln 10 and the burner 200 to supply oxygen and may be connected to the calciner 314 of the preheater 300, So that the salt can be prevented from being deposited.

Specifically, as the combustion gas and the raw material are mixed, lime (CaO) in the raw material and sulfur dioxide (SO ₂ ) in the combustion gas react to form calcium sulfite (CaSO ₃ ). Calcium sulfite is formed in the preheater 300 and in the main electrostatic precipitator of the conduit. On the other hand, if there is sufficient oxygen present in the pre-heating unit 300, the calcium sulfite to form the oxygen reacts with the calcium sulfate (CaSO ₄₎ in the pre-heater. If there is not enough oxygen at the inlet of the rotary kiln 10, calcium sulfate may decompose into lime and sulfur dioxide and remain immersed in the inlet of the rotary kiln. When oxygen is insufficiently present in the rotary kiln 10, calcium sulfate can be decomposed at a temperature of 1200 ° C.

Likewise, in the case where sufficient oxygen is not present in the preheating section 300, calcium sulfite can be decomposed into lime and sulfur dioxide. This decomposition increases the concentration of sulfur dioxide in the gas inside the rotary kiln 10, thereby causing the calcium salt to deposit on the wall inside the preheating unit 300.

The lance 100 is connected to the calcining furnace 314 of the preheating unit 300 so that enough oxygen is supplied to the preheating unit 300 to prevent the calcium salt from being deposited on the wall of the preheating unit 300 Can exist.

As shown in FIG. 3B, the plurality of injection paths 101, 102, and 103 provided at the tip 110 are inclined at a predetermined angle from the inside toward the outside of the tip, It can spread quickly in three dimensions.

3C, the other end portion 110 'can be replaced with the lance 100. The other end portion 110' has one injection passage 101 'having a smaller diameter than the inside diameter, So that the injection pressure of oxygen supplied from the liquefied oxygen storage tank can be improved.

4, the burner 200 includes a plurality of circular pipes concentric to the inside of the outer housing tube 210, and includes a lance connector 201 for connecting the lance 100 to the rear center, , An air inlet (not shown) for injecting air into the rear side, and a fuel inlet 205 for injecting fuel such as pulverized coal or oil at the rear outside.

The burner 200 includes a plurality of circular tubes provided inside the outer housing tube 210 and a first circular tube 212, a second circular tube 220, A first circular pipe (230), a fourth circular pipe (240) and a central pipe (260), and a first flow path (I) is formed between the first circular pipe (212) and the second circular pipe A second flow path II is formed between the two cylindrical tubes 220 and the third cylindrical tube 230 and a third flow path III is formed between the third cylindrical tube 230 and the fourth cylindrical tube 240 A fourth flow path IV may be formed between the fourth cylindrical pipe 240 and the central pipe 260 and a fifth flow path V may be formed inside the central pipe 260.

Here, air is injected into the first flow path I, the second flow path II and the fourth flow path IV, and the third flow path III is injected with fuel such as pulverized coal or oil, , And the fifth flow path (V) injects the oxygen introduced through the lance (100).

At this time, a donut-shaped spray plate 250 having a plurality of holes 255 is mounted at a tip portion between the fourth cylindrical pipe 240 and the central pipe 260, and the air introduced through the fourth flow pipe IV May be injected through the plurality of holes (255).

The outer ends of the second cylindrical pipe 220 and the third cylindrical pipe 230 are formed to be thicker and tapered in the tip direction so that the first flow path I and the second flow path II The swirling air can be swirled in the direction of the leading end so that swirling air having a directional outward direction through the tip of the second flow path II can be formed.

Since the flame generated through the burner 200 raises the temperature of the raw material and increases volatilization of the sulfur, the burner 200 adjusts and aligns the tip end positions of the raw material in the rotary kiln 10 so as to avoid flame, .

In addition, the burner 200 can move the second cylindrical pipe 220, the third cylindrical pipe 230 and the fourth cylindrical pipe 240 rearward according to the control of the control unit, The outside of the tip having a thick thickness of the second cylindrical tube 220 is abutted against the inside of the first cylindrical tube 212 to close the first flow path I and the third cylindrical tube 230 having a thick thickness The tip end outer side abuts against the inside of the second cylindrical pipe 220 to close the second flow path II.

The control unit may close the first flow path I or the second flow path II of the burner 200 and regulate the injection of air for generating the flame through the burner 200. [

The central pipe 260 diffuses and injects the oxygen introduced through the lance 100 connected to the lance connection port 201. Oxygen is mixed with the fuel such as pulverized coal or oil introduced through the third flow path III, Lt; / RTI >

That is, the oxygen introduced through the lance 100 is formed into a vortex by the plurality of injection passages 101, 102, and 103, diffuses through the central pipe 260 in three dimensions, and can generate flames by mixing with fuel.

The oxygen hatching system according to the embodiment of the present invention configured as described above can easily convert the firing atmosphere in the rotary kiln 10 into the firing atmosphere while reducing the fuel through the lance 100 and the burner , And the combustion property can be improved.

Hereinafter, the effects of the connection position of the lance 100 in the oxygen enrichment system according to the embodiment of the present invention will be described with reference to experimental examples.

Experimental Example  One

In Experimental Example 1, the lance 100 was connected to the calcining furnace 314 of the preheater 300 in the form of the calcining process for producing the cement shown in FIG. 2, and the calcining furnace 314 was charged with 400 to 500 Nm 3 / h Of oxygen.

Experimental Example  2

2, the lance 100 was connected to the inlet of the rotary kiln 10 in a form applied to the firing process for producing cement shown in FIG. 2, and 400 to 500 Nm 3 / h of oxygen was supplied to the rotary kiln 10 do.

Experimental Example  3

In Experimental Example 3, the lance 100 was connected to the burner 200 in a form applied to the cement manufacturing process shown in FIG. 2, and 400 to 500 Nm 3 / h of oxygen was supplied to the burner 200, .

As a result of the experiments according to Experimental Examples 1 to 3, Experimental Example 1 has an effect of preventing the salt from being deposited on the walls inside the preheating portion 300, but as shown in the following Table 1, There is no effect.

Experimental Example 2 has an effect on the combustion of the recycled fuel in the preheater 300 without increasing the combustion efficiency in the rotary kiln 10. However, it is difficult to control the temperature of the preheating unit 300 due to the temperature deviation and hunting at the lowermost end of the preheating unit 300, which is caused by the increase of the amount of the recycled fuel, when the oxygen is excessively injected at 500 Nm 3 / h or more .

On the other hand, Experimental Example 3 increases the combustion efficiency in the rotary kiln 10, reduces the fuel consumption of the preheating portion 300, and is effective in the combustion of the recycled fuel. Thus, in Experimental Example 3, it is possible to easily convert an ovoid atmosphere into an isotonic atmosphere.

The amount of fuel reduction in the rotary kiln 10 (tonnes / h) The fuel reduction amount (ton / h) of the preheating unit 300 Increase in recycled fuel (ton / h) Experimental Example 1 - - - Experimental Example 2 - 0.4 to 0.6 0.4 to 0.7 Experimental Example 3 0.4 to 0.7 0.4 to 0.6 0.4 to 0.8

Therefore, in the oxygen enrichment system according to the embodiment of the present invention, the lance 100 may be connected to the burner 200 to increase the combustion efficiency in the rotary kiln 10 to improve the combustibility.

Although the technical idea of the present invention has been specifically described according to the above preferred embodiments, it is to be noted that the above-described embodiments are intended to be illustrative and not restrictive.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

100: Lance 110:
120: connector 130: outer tube
140: stopper 200: burner
210: outer housing tube 212: first cylindrical tube
220: second round pipe 230: third round pipe
240: fourth circulation tube 250: spray plate
255: hole 260:
300: preheating part 314: calcined furnace

Claims (9)

A lance for oxygen supply;
A burner connected to the lance and extending inside the kiln; And
And a control unit connected to the lance and the burner, respectively,
The burner includes:
Outer housing tube; And
A first circular pipe, a second circular pipe, a third circular pipe, a fourth circular pipe and a central pipe provided inside the outer housing pipe,
A first flow path I into which air is injected is formed between the first circular pipe and the second circular pipe and a second flow path II through which air is injected between the second circular pipe and the third circular pipe is formed , A third flow path (III) in which pulverized coal or oil is injected is formed between the third circular pipe and the fourth circular pipe, and a fourth flow path (IV) through which air is injected between the fourth circular pipe and the center pipe A fifth passage (V) through which oxygen is injected through the lance is formed inside the center pipe,
Wherein the second cylindrical pipe and the third cylindrical pipe are formed to be movable backward, are thickened in a tip direction and are inclined,
Wherein,
Closing the first flow path by bringing the outside of the tip of the second cylindrical pipe into contact with the inside of the first cylindrical pipe by moving the second circular pipe backward to regulate the air injected from the first flow path, And the third circular tube is moved rearward to regulate the air injected from the second flow passage so that the outer side of the tip of the third circular tube abuts against the inside of the second circular tube so as to close the second flow path . ≪ / RTI >
The method according to claim 1,
The lance
A tip end portion having a plurality of injection paths inclined at a predetermined angle;
A connection pipe connected to the distal end portion; And
A stopper provided outside the connection pipe;
And an oxygen-enriched system.
The method according to claim 1,
The lance
A tip end having at least one injection passage having a diameter smaller than an inner diameter;
A connection pipe connected to the distal end portion; And
A stopper provided outside the connection pipe;
And an oxygen-enriched system.
The method according to claim 2 or 3,
Wherein the lance further comprises an outer tube enclosing the outside of the connection tube.
The method according to claim 1,
The burner
A lance connector to which the lance is connected at a rear center;
An air inlet for injecting air into the rear side; And
A fuel injection port for injecting fuel of pulverized coal or oil into the rear outer side;
And an oxygen-enriched system.
delete The method according to claim 1,
Further comprising a donut-shaped spray plate having a plurality of holes at a tip portion between the fourth circular tube and the center tube.
delete delete

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