JPS6112553Y2 - - Google Patents

Description

[Detailed explanation of the idea]

This invention relates to a cupola device, and particularly to a cupola device that supplies a predetermined amount of granular carbonaceous material to the cupola. A cupola used as a foundry melting furnace is one in which scrap or other metals are charged into the furnace along with carbonaceous materials, air is sent through the furnace to burn the carbonaceous materials, and the heat is used to melt the metals. However, due to the high cost of this carbonaceous material in cupola operation, there is a problem in that the melting cost is high, and for this reason, studies have been made to reduce the cost required for the carbonaceous material. The present invention was developed against this background, and in order to reduce melting costs, it uses granular carbon material and feeds the granular carbon material into a furnace for combustion. The purpose is to provide concrete means for achieving this goal. In order to achieve this purpose, the present invention includes (a) a cupola equipped with a ventilation passage for feeding combustion air into the furnace, and (b) a predetermined amount of granular carbon material in the cupola. A granular carbonaceous material supply device for supplying the granular carbonaceous materials; (d) a pressurized chamber formed as a chamber of equal pressure; and (d) communicated with the ventilation passage of the cupola in order to guide the granular carbonaceous material supplied from the granular carbonaceous material supply device into the cupola. (e) an air ejector means disposed on the granular carbon material supply passage and ejecting air toward the ventilation passage side of the cupola in the supply passage; By the ejection action of the air ejector means, the granular carbonaceous material supplied from the granular carbonaceous material supply device and guided to the granular carbonaceous material supply passage is sent into the cupola,
They constructed a cupola device. Embodiments of the present invention will be described in detail below with reference to the drawings. In FIG. 1, the cupola device is cupola 10.
, a granular carbon material supply device 12 for supplying a predetermined amount of granular carbon material, a granular carbon material supply pipe 14 connecting the supply device 12 and cupola 10, and a granular carbon material supply pipe 14 arranged in the supply pipe 14. It is composed of an air ejector 16. The cupola 10 is of a general type used for melting foundry metals, and the furnace 20 has a furnace wall 18 made of refractory material, has an upright cylindrical shape, has a charging port 22 at its upper part, and has a furnace wall 18 made of a refractory material. Bullion, slag material, etc. are charged from there. On the other hand, above the hearth 24, there is a tapping port 26 from which the molten metal is taken out to the outside. A wind box 28 is disposed above the tap 26, and combustion air sent from a blower is introduced here from a blow pipe 30 and is temporarily stored therein. The accumulated air flows into the blast pipe 32 extending from the wind box, and is sent into the furnace 20 through the tip forming the tuyere 34. In addition, in the cupola 10, the lower side of the hearth 24 is the hearth lid 3.
6, and a slag outlet 38 is provided at the bottom of the furnace 20 to take out the slag. As shown in FIGS. 2 and 3, the granular carbonaceous material supply device 12 includes a tank 42 supported by main body legs 40, and contains particles having a particle size of approximately 3 mm or less. Contains granular carbonaceous materials that are considered to be A motor 44 is fixed to the main body leg 40 by a mounting member 46 on the lower side of the tank 42, and the motor shaft 48 extends into the tank 42 and is a rotating shaft supported by a bearing stand 50. 52 by a coupling 54. The rotating shaft 52 is for rotating a stirring member (not shown) disposed in the tank 42, and thereby prevents the granular carbonaceous material contained in the tank 42 from hanging on the shelf. ing. A flexible tube 56 made of rubber is connected to the bottom of the tank 42.
While the granular carbonaceous material inside 2 is taken out to the outside,
Below the flexible tube 56 is a trough 58 for quantitative feeder.
is provided, through which the granular carbonaceous material is guided. The granular carbonaceous material led to the trough 58 is dropped into a hopper 62 by the vibration action of a metering feeder 60 disposed below the trough 58, and then a granular carbonaceous material supply pipe extending from the hopper 62. Sent to 14. Note that the bulge 64 formed at the center of the flexible tube 56 is for vibration absorption. Powdered carbon material supply device 1 composed of each of these elements
2 is entirely surrounded by an enclosing wall 66 as shown in FIGS. 1 to 3, and has a sealed pressurized chamber 68 inside.
This pressurized chamber 68 is connected to a communication pipe 70.
The pipe 3 is connected to the air pipe 32 by a
The pressure inside 2 is directed here. As shown in FIG. 1, the granular carbonaceous material supply pipe 14 has its tip located at the tuyere 34,
It serves as a supply passage for conveying the granular carbonaceous material sent out from the granular carbonaceous material supply device 12 into the furnace 20 . As shown in FIGS. 1 and 4, the granular carbon material supply pipe 14 has a pipe 72 and a pipe 74 in the vicinity of the tuyere
are connected. That is, the connecting end of one tube 72 has a male thread, and the connecting end of the other tube 74 has a male thread.
Female threads are provided at the connecting ends of the pipes 72 and 74, respectively, and these threads are screwed together to connect both the pipes 72 and 74. The inner surface of the tube 74 near this connection part is formed into a stepped shape, and
A cylindrical member 78 is fitted into the large diameter portion 76 . The cylindrical member 78 is held in a fixed position from both sides by the stepped surface 80 of the tube 74 and the distal end surface of the tube 72 at the front and rear (left and right in the figure) end surfaces. The cylindrical member 78 has a passage 82 for passing the granular carbon material inside thereof, and an annular groove 84 continuous in the circumferential direction on the outside thereof.
A large number of ejection holes 86 are provided to communicate with the inside of the pipe 74 and the inside of the pipe 74 . One end of an air supply pipe 88 is connected to the pipe 74 at a position opposite to this groove 84, and air sent out from the air supply source is guided to the groove 84, and then from a jet hole 86 to a granular carbon material supply pipe. It is now being ejected to 14. That is, the air ejector 1 for ejecting air within the granular carbonaceous material supply pipe 14 through each end of the pipes 72 and 74, the cylindrical member 78, and the air supply pipe 88.
6. Note that the cylindrical member 7
A seal ring 92 is disposed between the stepped surface 80 of the tube 74 and the end surface of the tube 72 to maintain airtightness. In the cupola device configured as above, the combustion air sent from the blower (not shown) is once stored in the wind box 28 and brought to a constant pressure, and then
Air is evenly blown into the furnace 20 from the tuyere 34 through the blast pipe 32. On the other hand, the granular carbonaceous material stored in the tank 42 is smoothly supplied to the quantitative feeder trough 58 through the flexible tube 56 by the stirring action based on the rotation of the motor 44, and further by the vibration action of the quantitative feeder 60. He is then dropped into Hoppa 62. The amount supplied to the hopper 62 can be set to a desired constant amount by adjusting the vibration intensity of the quantitative feeder 60. The granular carbonaceous material dropped into the hopper 62 is then guided to the granular carbonaceous material supply pipe 14.
Since the tip of the supply pipe 14 is located at the tuyere 34, the blow pipe 32 is located inside the tip of the supply pipe 14.
The internal pressure builds up and tries to prevent the smooth flow of carbonaceous materials. On the other hand, granular carbon material supply device 12
Since the same pressure as the pressure in the pressurizing chamber 68, that is, the pressure in the blast pipe 32, is acting on the hopper 62 or the granular carbon material supply pipe 14 on the side of the device 12, the two pressures cancel each other out. Air pipe 32
The internal pressure does not hinder the feeding of granular carbonaceous material. Now, air from an air supply source is sent through the supply pipe 88 to the groove 84 of the cylindrical member 78 located inside the granular carbonaceous material supply pipe 14, and this air flows from the jet hole 86 to the pipe 74. It is made to erupt forcefully. Then, the granular carbonaceous material sent out from the granular carbonaceous material supply device 12 to the pipe 72 by the action of the ejected air is sucked toward the pipe 74 side, and
The tuyeres 34 are
pushed out, and further into Kyupora's furnace 20
It is sent inside. In such equipment, the granular carbonaceous material injected into the Kyupora furnace has high combustion efficiency and the temperature inside the furnace is high, so the amount of carbonaceous material used is reduced, and the coal as granular carbonaceous material is Since it is possible to use low-quality charcoal such as scrap, the melting cost can be reduced in combination. In addition, the method described above in which granular carbonaceous material is fed into the furnace by air injection has the advantage that the amount of carbonaceous material supplied can be easily adjusted, and as the temperature inside the furnace increases, the amount of pig iron used as a raw material can be reduced. Instead, it becomes possible to increase the amount of steel scrap mixed, which has the effect of reducing raw material costs accordingly. Moreover, when granular carbonaceous material is used, the CO gas in the furnace is enriched and the reducing ability is increased, so the above-mentioned apparatus has the secondary effect of improving the yield of ferrosilicon. In other words, ferrosilicon is added to the Kyupora furnace in order to adjust the composition of the molten metal, but since this ferrosilicon is oxidized and depleted during metal melting in the furnace, the amount of depletion is anticipated in advance when blending. However, as the reducing atmosphere becomes stronger, the amount of depletion decreases, and the yield improves accordingly. By the way, in the above device, it is not necessarily necessary to provide the pressurizing chamber 68 in the granular carbon material supply device 12. However, in this case, the pressure inside the blast pipe 32 that is applied to the tuyere 34 of the powder supply pipe 14 causes the powder carbon material to be transferred to the carbon material supply device 1.
It acts as a force that causes the flow to flow backwards to the second side. Therefore, in order to send the carbonaceous material in the carbonaceous material supply pipe 14 into the furnace 20, it is necessary to overcome this pressure and blow out air, and the feeding force based on this blowout and the above pressure are The difference with the return force becomes the driving force for sending the carbonaceous material into the furnace 20, and there will be a corresponding loss in the amount of air. On the other hand, in the above device, the backflow effect of the internal pressure of the blast pipe 32 is canceled by the pressurizing action of the pressurizing chamber 68, and the jetting force from the jetting hole 86 in the cylindrical member 78 is used to send out the granular carbonaceous material as is. It has the excellent feature of being a propulsion force and causing no loss in air volume. Furthermore, the carbon material supply device 12 is
Since the entire pressure chamber 68 is configured to be housed within the pressurizing chamber 68, unlike the case where pressure is applied only to the tank 42, etc. that accommodates the carbonaceous material, for example,
The granular carbonaceous material is not leaked from the joint between the tank 42 and the flexible tube 56, and the granular carbonaceous material is not blown away from the metering feeder trough 58 or the metering feeder 60. That is, quantitative feeder 60
can reliably perform the function of supplying the set amount of carbon material to the hopper 62, and thereby the furnace 2
Therefore, combustion conditions within the range 0 can be easily and reliably adjusted. Next, test examples conducted using such an apparatus will be described below, and one and two of the above-mentioned effects will be specifically shown. Test Example A running test was conducted using the equipment and blending conditions shown in Tables 1 and 2 and the carbon material injection conditions shown in Table 3. The resulting furnace temperature (vertical axis) one hour (horizontal axis) curve is shown in Figure 6, and the carbon content (%)
The (vertical axis) one hour (horizontal axis) curve is shown in FIG. 7, and the ferrosilicon yield (vertical axis) one hour (horizontal axis) curve is shown in FIG. 8, respectively. Note that A in the figure indicates the time when the blowing of granular coke starts.

【table】

[Table] These results show that by feeding a small amount of granular carbonaceous material, the temperature inside the furnace increases quickly, the yield of ferrosilicon increases, and the amount of carbon in the gun also increases. has been shown to increase rapidly. It should be noted that the above-mentioned embodiments are merely examples of the present invention, and the present invention can be configured and implemented in various other ways. For example, it is desirable to connect the granular carbonaceous material supply pipe to the tuyere of the cupora, but it is not necessarily limited to this, and it should be connected to any part of the ventilation passage consisting of the ventilation pipe, wind box, etc. In addition, the ejector means is such that a pipe having an air jet nozzle formed at the tip thereof is inserted into the coke supply pipe, and the granular carbonaceous material is sucked into the coke supply pipe.
In addition to being configured to perform extrusion, it is also possible to implement it in various ways depending on the conditions of use and the like. As described in detail above, the cupola device according to the present invention includes a granular carbon material supply device that supplies granular carbon material,
hermetically surrounding the granular carbonaceous material supply device;
There is a pressurized chamber in which pressure is applied in the ventilation passage to Kyupora, a granular carbon material supply passage that guides the carbon material into the Kyupora furnace, and a granular carbon material supply passage that blows out air in the same passage to feed the granular carbon material into the furnace. and air ejector means for feeding the air into the air. In such an apparatus, a desired amount of granular carbonaceous material can be fed into the furnace during metal melting, and the temperature inside the furnace rises relatively quickly, making temperature control easy. In addition, the combustion efficiency of granular carbonaceous material is high, and therefore the temperature rise is also high, so the amount of carbonaceous material used is reduced.
Furthermore, it becomes possible to use low-quality charcoal, resulting in a reduction in melting costs. Furthermore, if the temperature inside the furnace is raised, it becomes possible to mix a large amount of steel scrap, which reduces raw material costs, and the yield of ferrosilicon increases due to the enrichment of CO gas inside the furnace. It has some excellent features.

[Brief explanation of the drawing]

FIG. 1 is a side view (partially sectional view) showing a cupola device as an embodiment of the present invention, and FIGS. 2 and 3 are a front view and a side view, respectively, of the granular carbonaceous material supply device in FIG. 1. It is a diagram. FIG. 4 is a side sectional view of the main part showing the ejector in FIG.
The figure is a perspective view of the cylindrical member in FIG. 4. FIGS. 6 to 8 are graphs showing the test results. 10: Kyupora, 12: Powdered carbon material supply device, 1
4: Powder carbon material supply pipe, 16: Air ejector, 2
0: Furnace, 28: Wind box, 30, 32: Air pipe, 6
6: Surrounding wall, 68: Pressurized chamber, 70: Communication pipe, 78:
Cylindrical member, 84: Groove, 86: Nozzle hole, 88: Air supply pipe.

Claims (1)

[Scope of Claim for Utility Model Registration] A cupola equipped with a ventilation passage for sending combustion air into a furnace, a granular carbon material supply device that supplies a predetermined amount of granular carbon material to the cupora, and the granular carbon material. a pressurized chamber formed as a sealed chamber surrounding the entire supply device, the sealed chamber communicated with the ventilation passage, and formed as a chamber having a pressure equal to the pressure within the ventilation passage; and the powder particles. A granular carbonaceous material supply passage communicating with the ventilation passage of the cupola in order to guide the granular carbonaceous material supplied from the carbonaceous material supply device into the cupola, and disposed on the granular carbonaceous material supply passage. and includes an air ejector means for ejecting air toward the blowing passage side of the cupola in the supply passage, and the air ejector means is configured to eject air from the granular carbon material supplying device by the ejection action of the air ejector means. A cupola device characterized in that the powdery carbonaceous material guided through the powdery carbonaceous material supply passage is fed into the cupola.