KR100362684B1 - device for adjusting the differential pressure of distributor in fluidized bed - Google Patents

Abstract

The present invention is composed of a three-stage fluidized bed reactor consisting of a preheating furnace 40, a preliminary reduction reactor 30, the final reduction reactor 20, the melt gasifier 10 connected thereto, the flow of ore and reducing gas A first and second or third ore ore conduits 23, 33 or 43 and first or second or third gas conduits 11 or 22 or 32, and the nozzle member 72 through which the reducing gas passes. The first, second and third blocking plates (24, 34, 44) having a plurality of each in the reactor (20, 30, 40), respectively, while the exhaust gas is finally discharged through the exhaust gas pipe (61) In the equipment for manufacturing molten iron having a wet damper 70 passing therethrough, the nozzle holes 72a of the nozzle member 72 are formed on the upper surfaces of the first, second and third dispersion plates 24, 34, 44. Equipped with a plurality of control plate (1) perforated with a plurality of control holes (3) overlapping with the horizontal movement, the control plate (1) is proportional to the range that the nozzle hole (72a) and the adjustment hole (3) overlap each other By adjusting the outlet diameter of the nozzle hole (72a) Through distribution plate provides a differential pressure regulating device of the fluidized-bed reaction constituting connected to the rod end of the cylinder member (2) to control a pressure difference in the distribution plate.

Description

Device for adjusting the differential pressure of distributor in fluidized bed

The present invention relates to a device that can control the differential pressure of the dispersion plate installed in the fluidized bed reactor in the process of reducing the iron ore using a fluidized bed reactor, more specifically iron ore is preheating, pre-reduction and final reduction In-process reactor to produce molten iron by continuously feeding the ore into the multi-stage fluidized bed reactor consisting of the reactor and supplying the reducing gas generated from the molten gasifier to the lower part of each reactor to interact with the charged ore to continuously perform the reduction reaction. It is possible to perform stable and continuous operation by lowering the differential pressure of the dispersion plate by appropriately adjusting the outlet diameter of the nozzle member of the dispersion plate so as to suppress the unstable operation or interruption of the operation due to the increase in the differential pressure in the dispersion plate installed in the inside. The present invention relates to a dispersion plate differential pressure control device for a fluidized bed reactor.

In general, a method using a blast furnace has been mainly used to produce molten iron by reducing iron ore.

However, the blast furnace method is used through the pre-treatment of the coking and sintering process for the efficiency of the manufacturing process, such a pre-treatment process requires a huge investment cost, pollute the environment, and caused problems in resource supply and demand.

In order to overcome the problems of the blast furnace method and use a molten iron ore and ordinary coal directly without pretreatment, a melt reduction method has recently emerged, and a representative example thereof is U.S. Patent No. 4,978,378. In the method described in US Patent No. 4,978,378, the use of raw iron ore and coal can be used to simplify the process and equipment by omitting the pretreatment of raw materials such as the sintering process and the coking process, compared to the existing blast furnace method.

On the other hand, the general molten iron manufacturing equipment, as shown in Figure 3, a three-stage flow reduction reactor consisting of a preheating furnace 40, preliminary reduction reactor 30 and the final reduction reactor 40 and the coal filling layer is formed It is composed of a molten gasifier (10), the iron ore at room temperature continuously charged to the preheating furnace 40, which is the uppermost reactor through the ore loading pipe 63 of the ore charging bin 60 is the first And the first, second and third gas conduits (11, 22) from the melt gasifier (10) while sequentially passing through the three-stage flow reduction path through the second and third ore conduits (43) (33) (23). By contacting the high temperature reducing air supplied through the (32) is converted to a high temperature reduction spectroscopy which is elevated and more than 90% reduction is discharged, the reduction spectroscopy into the molten gasifier 10 in which the coal-filled layer is formed Continuously charged and melted in the coal packed bed to be melted and melted It is discharged out of the gasifier 10.

In addition, in the molten gasifier 10, the bulky coal is continuously supplied from the upper part of the furnace to form a coal filling layer having a constant height in the furnace, and a plurality of tuyere formed at the lower end of the filling layer outer wall. Oxygen is blown into the packed bed through which coal is burned in the packed bed, and the combustion gas is converted into a high temperature reducing air stream while raising the packed bed.

In addition, the exhaust gas discharged from the preheating furnace 40 is supplied to the wet vacuum cleaner 50 through the exhaust gas conduit 42 to remove dust, and then discharged to the outside through a stack connected to the exhaust pipe 51.

In addition, in the preheating furnace 40, the preliminary reduction reactor 30, and the final reduction reactor 20, which are fluidized bed reactors, the ore charged into the furnace by the reducing gas supplied from the lower part may be fluidized to a fluidized bed height having a predetermined height. As shown in FIG. 1, the grooves of the assembly grooves 74 are formed in an annular shape on the inner wall of each of the reactors 20, 30, and 40 formed by the refractory bricks, so that the reducing gas can pass therethrough. The outer periphery edges of the dispersion plates 24, 34, 44 in which the nozzle member 72 which penetrated the nozzle hole 72a was attached were attached.

The finely-reduced iron produced in the process of performing a fluid reduction process in the fluidized bed reactor equipped with such dispersion plates 24, 34, 44 contains a large amount of fine powder at the stage of charging into the melt gasifier 10. Therefore, a large amount of fine powder scattered from the molten gasifier 10 is supplied to the upper fluidized bed reactor while being contained in the reducing gas generated in the molten gasifier 10, and each of the dispersion plates 24 installed in the fluidized bed reactor. The nozzle holes 72a of the nozzle members 72 of the nozzles 34 and 44 were blocked, thereby making it difficult to supply the reducing gas through the nozzle holes 72a.

That is, the ore is flow-reduced through the preheating furnace 40, the preliminary reduction path 30 and the final reduction path 20 through the ore charging pipe 63 is charged into the melt gasifier 10, the molten gasifier The reducing gas generated in (10) is introduced into the bottom of the final reduction path 20, the preliminary reduction path 30, and the preheating furnace 40 through the gas lift pipe, so that the first, second, and third dispersion plates 24 of each reactor 24 are reduced. Fines contained in the reducing gas introduced in a series of molten iron manufacturing processes supplied to the fluidized bed through the (34) and (44) and the fluidized bed at the top of the first, second and third dispersion plates 24, 34 and 44. The nozzle holes 72a of the plurality of nozzle members 72 mounted on the distribution plates 24, 34 and 44 are gradually blocked by falling lights from the reactor, thereby increasing the differential pressure in the distribution plate in the reactor. Ore flow and flow becomes impossible and eventually there was a problem to stop the operation.

Accordingly, the present invention has been made in order to solve the above problems, the object of the present invention is to easily adjust the nozzle hole exit size of each nozzle member of the dispersion plate through which the reducing gas passes, The differential pressure at the bottom is always maintained to enable a stable operation of the molten iron manufacturing process and to provide a differential plate pressure control device of the fluidized bed reactor to ensure long-term.

1 is a detailed view showing a blocking plate installed in a fluidized bed reactor;

Figure 2 is a detailed view showing a dispersion plate differential pressure control device of a fluidized bed reactor according to the present invention,

Figure 3 is a schematic diagram showing a molten iron manufacturing equipment employing a dispersion plate differential pressure control device of a fluidized bed reactor.

Explanation of symbols on the main parts of the drawings

1 ..... Adjusting plate 2 ...... Cylinder member

3 ..... Control holes 11, 22, 32 ... 1, 2 and 3 gas conduits

23, 33, 43 ... 1,2,3 or 3 Ore Conduits 24,34,44 ... 1,2,3,3 Block

28,38,48 ... nitrogen valve 29,39,49 ... nitrogen purge gas line

72 .... Nozzle member 72a .... Nozzle hole

As a technical configuration for achieving the above object, the present invention

Three-stage fluidized-bed reactor consisting of preheating furnace, pre-reduction furnace, and final reduction furnace, consisting of molten gasification furnace connected thereto, and the first, second and third ore conduits and the ore and reducing gas flows And a third gas conduit, each having first and second and third blocking plates having a plurality of nozzle members through which the reducing gas passes, and a wet vibration damper through which the exhaust gas discharged through the exhaust gas pipe passes. In the equipment for manufacturing molten iron,

On the upper surfaces of the first, second and third dispersion plates, a control plate having a plurality of control holes perforated with the nozzle holes of the nozzle member is horizontally movable, and the control plate is proportional to a range in which the nozzle holes and the control holes overlap each other. By adjusting the outlet diameter of the nozzle hole is provided by the distribution plate differential pressure control device for a fluidized bed reactor characterized in that it is connected to the rod end of the cylinder member to control the differential pressure in the dispersion plate through it.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a detailed view showing the dispersion plate differential pressure control device of the fluidized bed reactor according to the present invention, Figure 3 is a schematic diagram showing the molten iron manufacturing equipment employing the dispersion plate differential pressure control device of the fluidized bed reactor.

As shown in Figs. 2 and 3, the apparatus 200 of the present invention is charged to the bottom of each reactor to reduce the charged ore while charging the ore into each reactor 20, 30, 40 in turn. In the process of manufacturing molten iron by supplying a reducing gas, the nozzle members 72 of the first, second, and third dispersion plates 24, 34, 44 installed in the respective reactors 20, 30, 40 are The outlet diameter of the nozzle hole 72a of the nozzle member 72 to which the reducing gas is supplied is reduced so as to lower the differential pressure that is increased by being blocked by the fine powder which rises together with the reducing gas and the iron ore falling downward in the fluidized bed. As such, the device 200 is composed of a control plate (1) and the cylinder member (2).

That is, the adjusting plate 1 is formed by passing through a plurality of adjusting holes 3 corresponding to the nozzle members 72 mounted on the first, second, and third dispersion plates 24, 34, 44. , 2 and 3 dispersion plate 24, 34, 44 as the disc member assembled on the upper surface to move back and forth, the outer periphery of the throttle plate (1) fluidized bed reactor (20, 30, 40) Is assembled in the ring-shaped upper assembly groove 4 formed in each inner wall of the upper assembly groove 4 is the outer periphery of the first, second and third dispersion plates 24, 34, 44 Equipped with an upper portion of the assembly groove 74 formed on the inner wall of the reactor (20, 30, 40) to be assembled.

Here, the adjustment hole (3) is formed to be punched equal to or larger than the inner diameter of the nozzle hole (72) so as to coincide with the nozzle hole (72) when fully overlapped, the outer diameter size of the upper assembly groove (4) Is preferably formed larger than the outer diameter size of the control plate 1 so that the front and rear movement of the control plate (1) is made smoothly.

The control plate 1 is a range in which the nozzle hole 72a and the control hole 3 of the nozzle member 72 mounted on the first, second and third dispersion plates 24, 34, 44 overlap each other. Cylinder fixedly installed as a non-illustrated fixing member on the outer side of the reactor (20, 30, 40) to adjust the size of the outlet diameter of the nozzle hole 72 is supplied from the bottom according to the size It is connected to the rod end of the member (2).

Accordingly, a differential pressure gauge (not shown) installed in the reactors 20, 30 and 40, respectively, to measure the differential pressure in the upper and lower portions of the first, second, and third dispersion plates 24, 34, 44. By comparing the differential pressure measurement value and the set differential pressure value by the control hole (3) of the control plate (1) capable of moving the exit diameter of the nozzle hole 72 back and forth when it is 0.5 times or more than 0.2 times the normal fluidized bed differential pressure. By widening or narrowing, it is possible to maintain the differential pressure in the upper and lower portions of the first, second and third dispersion plates 24, 34 and 44 in the fluidized bed through which the reduction reaction is carried out to 0.2 to 0.5 times the normal fluidized bed differential pressure. desirable.

In addition, the rod of the cylinder member 2 penetrating the inner wall of the reactor (20, 30, 40) heat-resistant sealing member (9) to prevent the internal pressure through the gap of the connection portion to flow out Is preferably installed.

In addition, the first, second and third gas conduits 11, 22, 32 are completely sealed by differentiation and ore at the outlet diameter of the nozzle member 72, so that the differential pressure increase is rapidly increased or the control plate 1 When normal operation is not performed by this thermal expansion or the like, the charging of the ore is stopped and the shutoff valves 21, 31 and 41 of the first, second and third ore conduits 23, 33 and 43 are closed to close the ore flow. Nitrogen purging having nitrogen valves 28, 38, and 48 to supply nitrogen purging gas at room temperature to the lower side of the first, second and third dispersion plates 24, 34 and 44 in the stopped state. The gas lines 29, 39 and 49 are connected to each other.

At this time, the nitrogen gas supply pressure supplied to the lower side of the first, second, and third dispersion plates 24, 34, 44 through the nitrogen purge gas lines 29, 39, 49 is the reducing gas. It must be greater than the supply pressure of the reducing gas to prevent reverse flow.

The operation and effects of the present invention as described above will be described.

As shown in FIG. 3, the ore is flow-reduced and melted through the preheating furnace 40, the preliminary reduction reactor 30, and the final reduction reactor 20 through the ore charging tube 63 from the charging bin 60. Charged into the gasifier 10, the reducing gas is in turn to the lower portion of the final reduction reactor 20, preliminary reduction reactor 30 and preheating furnace 40 through the gas rise pipe generated in the molten gas furnace 10 As it is introduced, a series of melt reduction processes are supplied to the fluidized bed through the first, second, and third dispersion plates 24, 34, 44 of each reactor.

In this process, the fine powder contained in the reducing gas introduced into the lower side of the first, second, and third dispersion plates 24, 34, 44, and falling from the fluidized bed above the respective dispersion plates 24, 34, 44. When the nozzle holes 72a of the nozzle members 72 of the distribution plates 24, 34 and 44 are gradually blocked by a fall light, the pressure difference in the distribution plates 24, 34 and 44 increases. In this case, normal ore flow and flow becomes impossible.

During the melt reduction process while monitoring the differential pressure as a differential pressure gauge for measuring the differential pressure in each of the dispersion plates 24, 34 and 44, the differential pressure value measured as the differential pressure gauge and the preset normal fluidized bed differential pressure are compared with each other. When the difference is more than 0.5 times, the nozzle hole by moving the control plate (1) installed on the upper surface of the dispersion plates 24, 34, 44 of the corresponding reactor (20, 30, 40) The outlet diameter of the nozzle hole formed while the control hole 3 of 72a and the distribution plate 1 overlap each other is enlarged, and the differential pressure in a distribution plate is reduced.

That is, when it is detected that the differential pressure value in the distribution plates 24, 34, 44 increases by more than 0.5 times the normal fluidized bed differential pressure, the cylinder member is installed in the corresponding reactor (20) (30) (40) (2) is operated to move the control plate 1 assembled on the corresponding dispersion plates 24, 24, 44 so as to be movable back and forth to the left in the drawing. In this case, since the overlapping area between the adjusting hole 3 formed in the adjusting plate 1 and the nozzle hole 72a of the nozzle member 72 corresponding thereto can be enlarged, the outlet diameter of the nozzle hole can be enlarged. The differential pressure in the upper and lower parts of the dispersion plates 24, 34 and 44 is lowered, whereby the differential pressure can be lowered normally.

On the other hand, when the differential pressure measured by the first, second and third dispersion plates 24, 34 and 44 falls below 0.2 times the normal fluidized bed differential pressure, reverse the operation of the corresponding cylinder member 2 in reverse. By moving the control plate 1 connected to the right side in the drawing to reduce the overlap between the control hole 3 of the control plate 1 and the nozzle hole 72a of the nozzle member 72 to reduce the exit diameter of the nozzle hole. Reduce the size In this case, the upper and lower differential pressure in the dispersion plate can be increased to adjust to a normal value.

Thus, the throttle plate 1 is operated back and forth by the cylinder member 2 so that the differential pressure of the dispersion plates 24, 34, 44 can be maintained at 0.2 to 0.5 times the normal fluidized bed differential pressure, and the cylinder member 2 ) Is an operating member whose front and rear motions are controlled by a controller that compares the measured differential pressure measured by the differential pressure gauge with the normal differential pressure value.

In addition, during the melt reduction process, the control plate 1 is thermally expanded by a high temperature reducing gas for a long time, so that the back and forth operation is not performed smoothly, or the pressure difference between the dispersion plates 24, 34, 44 increases rapidly. When increasing to approximately the same value as the normal fluidized bed differential pressure, the ore loading is interrupted and the shutoff valves 21, 31 and 41 of the first, second and third ore conduits 23, 33 and 43 are operated to ore flow. In the stopped state, the nitrogen purging gas line branched from the first, second and third gas conduits 11, 22, 32 installed in communication with the lower part of the reactor 20, 30, 40 ( 29. The valves 28, 38 and 48 of the valves 39 and 49 are opened.

In this case, the nitrogen gas at room temperature is supplied to the lower side of the corresponding distribution plates 24, 34, 44, and supplied through the nozzle member 72 into the fluidized bed, thereby smoothly moving back and forth by the cylinder member 2. Cool the heat-expanded throttle plate 1 to be made. When the control plate 1 is normally cooled by the nitrogen purge gas continuously, the nitrogen valves 28, 38 and 38 are closed to stop the supply of further nitrogen gas and close the shutoff valve 21. Open (31) (41) to resume ore supply flow to allow normal operation to resume.

<Example>

1) Fluidized bed reactor specifications and conditions

end. Preheating Furnace, Preliminary Reduction Furnace, Final Reduction Furnace

-Reduction part (distribution plate) inner diameter: 0.3m

-Enlarged part inner diameter: 0.7m

-Conical bottom angle: 4 degrees

-Slope height (on the surface of the dispersion plate): 4.0m

-Cylindrical upper height: 2.5m

-Depth of dispersion plate: 3.0m

I. Nozzle

-Nozzle outlet inner diameter: 10 mm

-Nozzle Outlet Diameter Control Range: 7 ~ 10mm

All. Raw material

Iron ore (-8mm)

-Chemical composition: T. Fe: 62.17%, FeO: 0.51%, SiO ₂ : 5.5%, TiO ₂ : 0.11%,

Mn: 0.05%, S: 0.012%, P: 0.65%, Number of crystals: 2.32%

-Particle size distribution: -0.05mm: 4.6%, 0.05 ~ 0.15mm: 5.4%, 0.15 ~ 0.5mm: 16.8%,

0.5-4.75mm: 59.4%, 4.75-8mm: 13.8%

Reducing gas

-Chemical composition

CO: 65%, H ₂ : 25%, CO ₂ : 5%, N ₂ : 5%

-Temperature in the fluidized bed

Final Reduction Furnace: 850 ℃, Preliminary Reduction Furnace: 770 ℃, Preheating Furnace: 680 ℃

-Flow rate

1.3 to 1.5 m / s (based on Reactor 1 dispersion plate)

- pressure

2.5 to 3.0 bar, g

-Fine addition amount

100 g / N㎥

When the experiment was performed by adding a large amount of fine powder (100 g / Nm3) in the inlet gas during the experiment with the fluidized bed reactor and the experimental conditions as described above, the differential pressure of the dispersion plate was increased with the passage of time. As a result of adjusting the exit diameter of the nozzle hole of the nozzle member 72 by moving back and forth as the cylinder member 2, it was detected that the dispersion plate differential pressure was lowered from 250 mbar to 100 mbar or less.

In addition, when the experiment was conducted by adding only a large amount of fine powder (100 g / Nm 3) without using the control plate 1, the experiment duration was about 40 hours, but the control plate 1 was used to adjust the differential pressure of the dispersion plate. In the case of progressing the experiment was possible to continue for more than 60 hours. Particularly, when the experiment was conducted by connecting the nitrogen purging gas lines at the bottom of each reactor, it was found that the control plate 1 was not only smooth in operation but also extended in the experiment duration, which allowed 70 hours or more.

According to the present invention as described above, the nozzle hole outlet size of the nozzle member overlapped with the adjustment hole by having a control plate having a plurality of control holes on the upper surface of the dispersion plate installed in the reactor and a cylinder member for moving back and forth By maintaining the differential pressure of the dispersion plate is kept constant, the molten iron manufacturing process can be stably performed without interruption of operation, and the effect of ensuring long-term operation is obtained.

While the invention has been shown and described with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit or scope of the invention as set forth in the claims below. I would like to clarify that knowledge is easy to know.

Claims (3)

The three-stage fluidized-bed reactor consisting of a preheating furnace 40, a preliminary reduction reactor 30, and a final reduction reactor 20, consisting of a melt gasifier 10 connected thereto, the flow of ore and reducing gas flow 1, 2, 3 ore conduits 23, 33, 43, and 1, 2, 3 gas conduits 11, 22, 32, and a plurality of nozzle members 72 through which the reducing gas passes. The first, second, and third blocking plates 24, 34, and 44 having the reactors 20, 30, and 40 are respectively provided while the exhaust gas discharged through the exhaust gas pipe 61 passes. In the equipment for manufacturing molten iron equipped with a wet vibration damper (70), On the upper surfaces of the first, second, and third dispersion plates 24, 34, 44, a control plate 1 which drills a plurality of control holes 3 overlapping with the nozzle holes 72a of the nozzle member 72. Equipped with a horizontally movable, the control plate 1 is adjusted to the outlet diameter of the nozzle hole (72a) in proportion to the overlapping range of the nozzle hole (72a) and the adjustment hole (3) through the dispersion plate Dispersion plate differential pressure control device for a fluidized bed reactor, characterized in that connected to the rod end of the cylinder member (2) to adjust the differential pressure of the upper and lower parts. The method of claim 1, The size of the outlet diameter of the nozzle hole 72 is such that the pressure difference between the first, second, and third dispersion plates 24, 34, 44 can be maintained at 0.2 to 0.5 times the normal fluidized bed differential pressure. Dispersion plate differential pressure control device for a fluidized bed reactor, characterized in that the widened or narrowed by the control hole (3) of the control plate (1) moved back and forth by. The method of claim 1, The first, second, and third gas conduits 11, 22, and 32 are completely sealed by differentiation and ore in the outlet diameter of the nozzle member 72, so that the differential pressure increase is increased sharply, or the control plate 1 is thermally expanded. Stop ore loading and close the shutoff valves 21, 31 and 41 of the first, second and third ore conduits 23, 33 and 43 when the ore flow is stopped. Nitrogen purging gas line 29 having nitrogen valves 28, 38, and 48 to supply nitrogen purging gas at room temperature to the lower side of the first, second, and third dispersion plates 24, 34, 44. Dispersion plate differential pressure control device for a fluidized bed reactor characterized in that the connection (39) (49).