JP2001263947A - Drying equipment - Google Patents

Abstract

(57) [Summary] PROBLEM TO BE SOLVED: To blow out internal air from an opening of a housing or to open air.
Reduce the suction of air, maintain the surrounding environment well and save
Achieve energy. A supply of dry air communicatively connected to a housing is provided.
Blower F to supply duct 42 ₁Is provided, and the blower F₁Luck
By rotating, dry air is supplied to the space S of the housing 40.
You. Blower F₁Supply duct 42 upstream of the installation position of
In addition, the intake air whose supply amount of dry air into the space S can be adjusted
An adjustment damper 44 is provided. Of the outlet 40b of the housing 40
On the outside, a blowout amount sensor 58 is provided. Blowing volume
The detection signal from the sensor 58 is input to the controller 46.
The controller 46 adjusts the intake air based on the detection signal.
The opening of the damper 44 is adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying apparatus for preliminarily drying an object to be charged in a rotary hearth furnace as a metal reduction processing apparatus.

[0002]

2. Description of the Related Art A metal oxide (iron oxide, nickel oxide, etc.), a reducing agent (coal, coke, etc.) and a binder are mixed and granulated, such as steelmaking dust or scrap chips from scrapped cars, to form a particle having a diameter of 6 mm. By forming a green pellet (object to be processed) of ~ 30 mm, charging the green pellet into a rotary hearth furnace and heating it to a high temperature of about 1200 ° C,
It is known to reduce and recover metal oxides in pellets. The green pellets are previously dried by a drying device before being charged into a rotary hearth furnace.

Referring to FIG. 4, a schematic configuration of the drying device is described. The drying device 10 includes a green pellet transport conveyor 14 inside a space S covered by a housing 12. The green pellets supplied to the charging hopper 16 are configured to be supplied to the transport conveyor 14 from the entrance of the housing 12 via the supply conveyor 18. The green pellets conveyed by the conveyor 14 are the case 1
The outlet 2 discharges toward the discharge conveyor 20.

[0004] The space S of the housing 12 is divided into four zones allowing the transfer of the green pellets by the transfer conveyor 14, and a circulation duct 22 communicating with the space S is provided for each zone. A circulation device 28 including a burner 24 and a hot air circulation fan 26 disposed in the duct 22 is disposed. Then, by operating the hot air circulation fan 26, the internal air sucked from the space S through the suction port of the circulation duct 22 is heated by the burner 24,
By blowing the obtained hot air toward the green pellets conveyed by the conveyor 14 from the outlet, the pellets are dried.

[0005] In the drying apparatus 10, if the internal air is circulated only in the space S, the humidity increases with time and the drying efficiency decreases, so the sub-supply duct 32 branched from the main supply duct 30 is connected to the sub-supply duct 32. Connected to each circulation duct 22,
Dry air is supplied through the supply ducts 30 and 32. A sub exhaust duct 34 communicating with each zone is connected to the main exhaust duct 36 so as to exhaust excess air in the space S through the exhaust ducts 34 and 36.

[0006]

In the drying apparatus 10, a change in the temperature of the dry air, a change in the temperature of the excess air, a change in the heating temperature of the internal air by the burner 24, and a dust collector (not shown) provided in the main exhaust duct 36 are provided. Due to various factors such as filter clogging, the supply amount of the dry air and the exhaust amount of the excess air change. In this case, if the balance between the supply amount of the dry air and the exhaust amount of the excess air is lost, the pressure inside the space S fluctuates greatly. When the internal pressure of the space S increases, dirty internal air blows out from the entrance and the exit of the housing 12, causing a problem of polluting the surrounding environment. Conversely, when the internal pressure of the space S decreases, low-temperature outside air is sucked into the space S from the inlet and the outlet of the housing 12, and the internal temperature decreases, so that the drying efficiency decreases and the burner 24 decreases.
Causes a problem of increased energy consumption. Then, space S
It is conceivable to reduce the blowing of the internal air and the suction of the outside air by adjusting and balancing the supply amount of the dry air and the exhaust amount of the excess air based on the result of measuring the internal pressure of the air. However, in the space S, since the internal air is forcibly circulated by the hot air circulating fan 26, the pressure difference is large depending on each position (for example, 15 degrees).
(Approximately 0 Pa) and there are pressure fluctuations, so there is no representative pressure measurement point that can be used stably, and it is extremely difficult to perform highly accurate adjustment based on pressure measurement. That is, there is a need for a means capable of accurately controlling and controlling the supply amount of the dry air and the exhaust amount of the excess air to reduce the blowing of the internal air and the suction of the outside air.

[0007]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks inherent in the prior art drying apparatus, and has been proposed in order to preferably solve the problem. It is an object of the present invention to provide a drying apparatus capable of reducing blow-out of air and suction of outside air, maintaining a favorable surrounding environment, and achieving energy saving.

[0008]

In order to overcome the above-mentioned problems and to achieve the initial object, a drying apparatus according to the present invention is provided with a means for conveying an object to be processed in a space covered by a housing. ,
While the object to be processed supplied from the inlet of the housing is conveyed to the outlet by the conveying means, the object is dried by hot air circulating inside the space, and dry air is supplied to the inside of the space via a supply duct. A drying device in which excess air in the space is exhausted through an exhaust duct, wherein the supply duct detects the amount of internal air blown from an opening of the housing; And a control means for adjusting and controlling the intake adjusting means based on a detection signal from the blowing amount detecting means, the intake adjusting means being capable of adjusting a supply amount of dry air to the inside of the space. It is characterized by the following.

[0009] In order to overcome the above-mentioned problems and achieve the initial object, a drying apparatus according to another invention of the present application is provided with a means for transporting an object to be processed in a space covered by a housing. The object to be processed supplied from the inlet of the body is dried by hot air circulating inside the space while being conveyed to the outlet by the conveying means, and the inside of the space is supplied with dry air via a supply duct, A drying device in which excess air in the space is exhausted through an exhaust duct, wherein the exhaust duct is provided in the exhaust duct, and a blowout amount detecting means for detecting a blowout amount of internal air blown out from an opening of the housing. And exhaust control means for adjusting an exhaust amount of surplus air in the space, and control means for adjusting and controlling the exhaust control means based on a detection signal from the blowout amount detecting means. And

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a drying apparatus according to the present invention will be described in detail by way of preferred embodiments with reference to the accompanying drawings.

[0011]

First Embodiment FIG. 1 shows a schematic configuration of a drying apparatus according to a first embodiment, and the same conveyor (transport means) 14 and circulating device 2 as those described in the above-mentioned prior art are used.
8 and the like (see FIG. 4), a casing 40 of the drying device 38 is provided with an inlet 40a for the object to be processed and an outlet 40b for the object to be conveyed by the conveyor 14 to be processed. While the object is conveyed from the entrance 40a to the exit 40b, the circulation device 28 is configured to be dried by the hot air circulated through the space S in the housing 40. A dry air supply duct 42 is connected to the casing 40 and a blower F ₁ is provided in the duct 42. By operating the blower F ₁ , the inside of the space S It is configured to supply dry air. Further, on the upstream side of the arrangement position of the fan F _1, dry air tunable intake control damper the supply amount of (intake adjusting means) 44 to the internal space S is disposed, said damper 44 as a control means The opening / closing control (adjustment control) is performed by the controller 46. Note that a heat exchanger 48 and a first throttle 50 are disposed in a supply duct 42 facing between the blower F ₁ and the housing 40.

[0012] The together with the exhaust duct 52 to the housing 40 are communicatively connected, it is exhauster F ₂ is disposed at the exhaust duct 52, by operating the exhaust fan F _2, the housing 4
It is configured to exhaust excess air from the inside of the space S of zero. The exhaust duct 52 between the casing 40 and the exhaust fan F ₂
In addition, a second restrictor 54 and a dust collector 56 are disposed.

A blow-out amount sensor 58 as blow-out amount detecting means is provided outside the outlet (opening) 40b of the housing 40. As shown in FIG. 2, the blowout amount sensor 58 includes a detection plate 60 rotatable by the internal air of the housing 40 blown out from the outlet 40b, and a rotation shaft 62 that rotates integrally with the detection plate 60. Angle detector 64 for detecting the rotation angle of
And a detection signal from the angle detector 64 is input to the controller 46. The controller 46 compares the detection angle from the angle detector 64 with a preset optimum angle of the detection plate 60, and adjusts the opening degree of the intake adjustment damper 44 so that the detection angle becomes the optimum angle. It is configured to adjust.
Note that the optimum angle of the detection plate 60 is set to a value such that the amount of internal air blown is within an allowable range without sucking outside air from the outlet 40b.

[0014]

Next, the operation of the drying apparatus according to the first embodiment will be described. Entrance 4 to the housing 40
The workpiece supplied from Oa is transported toward the outlet 40b via the transport conveyor 14 disposed inside the space S. The object to be processed is dried by hot air circulated by the circulating device 28 provided in the housing 40, and the outlet 4
Ob is discharged to the subsequent process.

A predetermined amount of dry air is supplied to the housing 40 through the supply duct 42 by the operation of the blower F ₁ , so that the humidity inside the space S is prevented from increasing, and the blower F By the operation of ₂ , the excess air inside the space S is exhausted through the exhaust duct 52. Even if the first throttle 50 and the second throttle 54 are fixed, the supply amount of the dry air and the exhaust amount of the excess air change due to the above-described various factors, and the openings such as the inlet 40a and the outlet 40b. In some cases, the amount of internal air blown from the air and the amount of external air sucked in may increase.

That is, from the outlet 40b, an amount of internal air is blown out in accordance with a change in the supply amount of the dry air and the exhaust amount of the surplus air, and the detection plate 60 rotates according to the blowout amount. The rotation angle is detected by the angle detector 64, and this detection signal is input to the controller 46. Then, the controller 46 compares the preset optimum angle with the detected angle, and adjusts the opening degree of the intake adjustment damper 44 so that the detected angle becomes the optimum angle.
That is, when the detection angle is rotating in the forward direction (in the direction of increasing the blowing amount) with respect to the optimum angle, the opening degree of the intake adjustment damper 44 is reduced to reduce the supply amount of the dry air,
On the other hand, when the intake air is rotating in the negative direction (the direction in which the amount of air is decreased), the opening degree of the intake adjustment damper 44 is increased so as to increase the supply amount of dry air. Thereby, the supply amount of the dry air and the exhaust amount of the surplus air are balanced, so that the amount of the internal air blown out from the outlet 40b is not significantly increased, or a large amount of the low-temperature outside air is not sucked. It can prevent environmental pollution and achieve energy saving.

Further, since the amount of internal air blown out from the outlet 40b is representative of the entire space S of the housing 40, stable control is possible, and the structure of the blowout amount sensor itself is simple. It can be provided at low cost.

[0018]

Second Embodiment FIG. 3 shows a drying device 66 according to a second embodiment.
Since the basic configuration is the same as that of the first embodiment, only different parts will be described, and the same members as described above will be denoted by the same reference numerals.

That is, the exhaust duct 52 has a second
An exhaust adjustment damper (exhaust adjusting means) 6 between the restrictor 54 and the dust collector 56, which is capable of adjusting the exhaust amount of excess air in the space S.
The damper 68 is controlled to be opened and closed by the controller 46. Note that, similarly to the first embodiment, a detection signal from a blowout amount sensor 58 that detects a blowout amount of internal air from the outlet 40b of the housing 40 is input to the controller 46.

In the drying device 66 of the second embodiment, the detection angle of the detection plate 60 detected by the blowing amount sensor 58 and the optimum angle are compared by the controller 46, and the detection angle is adjusted so that the detection angle becomes the optimum angle. The opening of the exhaust adjustment damper 68 is adjusted. That is, when the detection angle is rotating in the forward direction (in the direction of increasing the blowing amount) with respect to the optimum angle, the opening degree of the exhaust adjustment damper 44 is increased to increase the exhaust amount of the excess air, and conversely. In the case of turning in the negative direction (the direction in which the blowout amount decreases), the adjustment control is performed so that the opening degree of the exhaust adjustment damper 68 is reduced to reduce the exhaust amount of the excess air. Thereby, the supply amount of the dry air and the exhaust amount of the surplus air are balanced, so that the amount of the internal air blown out from the outlet 40b is not significantly increased, or a large amount of the low-temperature outside air is not sucked. It can prevent environmental pollution and achieve energy saving.

[0021]

[Modification] In each of the embodiments described above, the blowout amount sensor constituted by a detection plate and an angle detector has been described as the blowout amount detecting means. However, the detecting means is limited to this structure. For example, a thermocouple may be used. That is, the temperature in the vicinity of the outlet also changes in accordance with the change in the amount of high-temperature internal air blown out. Therefore, it is possible to detect this temperature change with a thermocouple and control the opening and closing of the intake adjustment damper and the exhaust adjustment damper. . The position of the blowout amount detection means is
The opening is not limited to the outlet as long as the internal air blows from the housing, and may be a position corresponding to the inlet or another opening. The interior of the housing may be divided into a plurality of zones as described in the related art, or may be a single room.

[0022]

As described above, according to the drying apparatus of the present invention, the amount of internal air blown out from the opening of the housing is detected, and the amount of dry air supplied or the amount of excess air exhausted is detected. Since the adjustment is made so that both can be balanced, it is possible to reduce the amount of outflow of dirty internal air from the opening and prevent contamination of the surrounding environment. Further, since the amount of inflow of low-temperature outside air from the openings can be reduced, it is possible to prevent the drying efficiency from lowering due to the lowering of the internal temperature, and to reduce the heat energy consumption.
Furthermore, the structure of the blowing amount detecting means is simple, and the manufacturing cost of the drying device can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a drying apparatus according to a first preferred embodiment of the present invention.

FIG. 2 is a schematic configuration diagram illustrating a blowout amount sensor of the drying device according to the first embodiment.

FIG. 3 is a schematic configuration diagram of a drying apparatus according to a second preferred embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a drying apparatus according to a conventional technique.

[Explanation of symbols]

 14 Conveyor (Conveying Means) 40 Case 40a Inlet 40b Outlet (Opening) 42 Supply Duct 44 Intake Adjustment Damper (Intake Adjustment Means) 46 Controller (Control Means) 52 Exhaust Duct 58 Blowing Amount Sensor (Blowing Amount Detecting Means) 68 Exhaust adjustment damper (exhaust adjustment means) S space

Continued on the front page F term (reference) 3L113 AA02 AA03 AB02 AB05 AC01 AC20 AC36 AC45 AC46 AC67 BA19 CA11 CB12 CB23 DA02 DA06 DA26 4K012 DE01 DE08 4K063 AA02 BA02 BA13 CA01 CA02 GA03 GA33 GA39

Claims (2)

[Claims] A means (14) for transporting an object to be processed is provided inside a space (S) covered by a housing (40), and an entrance (4) of the housing (40) is provided.
0a), while conveying the object to be processed to the outlet (40b) by the conveying means (14), while drying by hot air circulating inside the space (S), and inside the space (S) A drying device in which dry air is supplied through a supply duct (42) and surplus air inside the space (S) is exhausted through an exhaust duct (52). (40b) a blowing amount detecting means (58) for detecting a blowing amount of internal air blown from the supply duct (42), and a supply amount of dry air into the space (S) can be adjusted. Based on the detection signal from the intake adjustment means (44) and the blowout amount detection means (58),
A drying device, comprising: a control means (46) for adjusting and controlling the intake adjusting means (44). 2. A transfer means (14) for an object to be processed is disposed inside a space (S) covered by a housing (40), and an entrance (4) of the housing (40) is provided.
0a), while conveying the object to be processed to the outlet (40b) by the conveying means (14), while drying by hot air circulating inside the space (S), and inside the space (S) A drying device in which dry air is supplied through a supply duct (42) and surplus air inside the space (S) is exhausted through an exhaust duct (52). (40b) a blowing amount detecting means (58) for detecting a blowing amount of the internal air blown from the air duct (52), which is provided in the exhaust duct (52), and is capable of adjusting an exhaust amount of surplus air inside the space (S). Exhaust adjusting means (68), based on a detection signal from the blowing amount detecting means (58),
A drying device, comprising: a control unit (46) for adjusting and controlling the exhaust adjusting unit (68).