JP2008002768A - Cast iron chip drying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve productivity and to reduce product costs by directly returning cast iron chips not to a steel mill but to a foundry when carrying out recycling of turnings. <P>SOLUTION: The cast iron chips are sent to an upstream side of a transverse drum rotating at a certain inclination angle, a drum interior is formed into a hot air passage, and in a process of the turnings passing through the drum interior from the upstream side to a downstream side, about 100% of moisture and 60-80% of oil contents attached to the turnings are removed. Spiral fins are attached to a lengthwise wall surface in the transverse drum, suitable intervals between adjacent fins are partitioned by shuttering boards, and a composition is comprised wherein the cast iron chips are transferred while being lifted to a certain height and dropped in a drum internal space following rotation of the drum. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for drying dairy powder.

Dalai powder (shaving chips, chips) generated in the casting manufacturing process is returned to the steel mill as a raw material for recycling and reused, but it contains a lot of moisture and oil (at least 70% to 90%), and the treatment is troublesome. That is, when this is directly brought into the steelworks, it is necessary to take measures against environmental pollution problems caused by oil and water spills.
JP-A-5-34067

  In view of the above-mentioned present situation, the present invention allows the dairy powder to be dried under certain conditions to be returned directly to the foundry, enabling melting in an electric furnace, improving productivity and reducing costs. It will contribute to the transformation.

  The present invention feeds the Dalai powder generated in the product manufacturing process of the cast casting to the upstream side of the horizontal drum that rotates at a fixed inclination angle, and forms the inside of the drum in a hot air passage, and the Dalai powder upstream in the drum. In the process of passing from the side toward the downstream side, the moisture adhering to the dairy powder is removed to 100%, and the oil content is removed to about 60% to 80%. At this time, the hot air temperature is set so that the downstream side is hot and the upstream side is low, and the spiral fins are attached to the wall surface in the longitudinal direction in the horizontal drum, and an appropriate interval between adjacent fins is blocked. The plate is partitioned by a plate, and the dairy powder is transported while being dropped when the drum space is lifted to a certain height as the drum rotates.

  The present invention does not simply remove oil by applying dairy powder generated at a grinding work site to a press or a centrifuge, but removes 100% of moisture and 60% to 80% of oil by hot air drying. In this way, the horizontal rotation drum is used for simple and efficient operation, thereby contributing to reduction of product cost and improvement of productivity.

  FIG. 1 is a partially broken front view of an apparatus for carrying out the method of the present invention, and FIG. 2 is a side view. In the drawings, 1 is a hopper for supplying dairy powder, 2 is a screw conveyor for feeding provided on the bottom surface thereof, 3 is a hot air drying drum arranged in front of the hopper, and a fixed inclination angle onto the gantry 4 And a rotary kirin that allows hot air to pass from the downstream side (b) to the upstream side (a) in the drum. Specifically, the gear bands 5 are attached to a plurality of (two in the illustrated example) peripheral body portions in the length direction of the drum 3, and each of the gear bands 5 is placed on both sides across the width of the mount 4. A small gear 6 that meshes with the small gear 6 is arranged, and the small gear 6 is supported via a pair of support shafts 7 and its bearing means 8. Thus, 9 is a drive motor provided inside the gantry 4, and this rotation is transmitted to the chain ring 12 fixed to one of the support shafts 7 via the chain ring 10 and the chain 11, and approximately 1 A slow rotation of one revolution per minute is performed. At this time, the drum diameter and length can be arbitrarily designed. In this embodiment, the drum radius is 45 cm and the length dimension is 3 m.

  On the other hand, 13 is a blower disposed in the gantry 4, and 14 is a boiler device disposed adjacent to the outside thereof. Hot air from the boiler device is operated along with the operation of the blower 13 through the pipes 15 a and 15 b. Thus, it is fed to the downstream side (b) in the drum 3, and this feeding does not interfere with the discharge of the dairy powder, that is, it is discharged from above the drum toward the inside thereof. is there. At this time, reference numeral 16 denotes a hood chamber provided so as to cover a certain range on the downstream side including the pipe line 15b and the outlet end of the drum 3, and an exhaust port 17 is attached to the upper portion of the hood chamber 16. .

  On the other hand, 18 is another hood chamber provided so as to cover a certain range including the outlet side of the screw conveyor 2 on the upstream side of the drum 3, and an exhaust port 19 is attached to the upper portion thereof. It is.

The food chambers 16 and 18 are for collecting the oil and water vapor generated during the hot air drying process of the Dalai powder, which will be described below, without diffusing outwardly. The ports 17 and 19 are separately connected to a dust collector (not shown) through a connecting pipe.
In the present invention, a spiral fin 20 is formed on the inner peripheral surface of the drum 3 from the upstream side (A) to the downstream side (B). 20 has a blade height h of about 10 cm so that a relatively large internal space 21 is formed in the drum 3, and an appropriate interval in the circumferential direction is set between adjacent fins (examples). In this case, the weir plate 22 is provided so as to straddle between the two.

  In the apparatus having the above-described configuration, the dairy powder generated in the casting casting manufacturing process is fed into the supply hopper 1 and the dairy powder is quantitatively detected upstream of the drum 3 by the drive of the screw conveyor 2. It is made to be sent continuously. By the way, the drum 3 is rotated by driving of the drive motor 9, and hot air from the boiler device 14 is moved into the drum 3 downstream of the drum 3 through the duct 15 b along with the operation of the blower 13. Therefore, the hot air flows to the upstream side (a) through the relatively large internal space 21 formed in the drum 3 and temporarily stays in the hood chamber 18. In this way, the chamber is discharged from a discharge port 19 to a dust collector (not shown) while maintaining a constant temperature necessary for preheating and drying. At this time, the temperature in the hood chamber 16 is controlled to 180 ° C. to 200 ° C., and the temperature in the hood chamber 18 is controlled by control means (not shown) so as to be maintained at a temperature of 80 ° C. to 100 ° C. .

  By the way, the dairy powder fed from the screw conveyor 2 to the upstream side (b) of the drum 3 is moved downstream (b) through the spiral fins 20 provided on the inner peripheral surface of the drum 3 as the drum 3 rotates. In this case, the drum 3 is disposed at a constant inclination angle that descends as shown in the example toward the downstream side, and between the adjacent spiral fins 20. Since the weir plates 22 are provided at appropriate intervals so as to straddle the drum 3, the dairy powder transferred along the spiral fins 20 in the drum 3 can be rotated upward while being dammed up at the respective weir plate locations. It is made to pass over the weir plate and fall downward. That is, it is always lifted upward by a certain height in the drum 3 by the dam plate 22 and dropped to the bottom surface side, whereby the dairy powder is made in a preferred spraying state in the length direction in the drum 3, In addition, the drying process under the set conditions is performed by the hot air flowing through the internal space 21.

  The drying treatment according to the present invention is such that the moisture of the Dalai powder is suddenly removed to 100% and the oil content is removed to 60% to 80% in the horizontal rotary drum 3 described above. The sample collection port is provided near the exit end, and control is performed so that regular measurement is performed, and the change based on the measurement value can be made to vary the number of revolutions of the drum 3 as appropriate, or the hot air temperature can be changed. Or is done. Thus, these can be provided as separate devices provided with automatic control means such as a sequence circuit.

  The removal of the oil adhering to the dairy powder in the present invention so as to be 60% to 80% was obtained from the results of many experiments by the present inventor. In use, a large amount of gas is generated in the melting furnace (electric furnace), or the melting temperature rises too much, causing a problem of component change (quality deterioration). There is a problem of rust generation due to oxidation and the like, and as described above, it causes a problem that causes a reduction in the quality of recycled castings. Note that the water removal is performed to 100% in order to prevent a water vapor explosion during the dissolution.

  In the present invention, as described above, the dry treatment is performed so that the moisture of the dairy powder is removed by 100% and the oil content is removed between 60% and 80%, so that the dairy powder can be directly returned to the foundry to be efficiently recycled. In the drying process, the horizontal rotating drum is used to perform the process simply and quickly. In addition, since it can be used by regenerative melting at a foundry, it contributes to reducing manufacturing costs and improving productivity.

It is a partially broken front view of the apparatus which enforces this invention method. It is said partially broken side view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Supply hopper 2 Screw conveyor 3 Drum 4 Mount 5 Gear belt 6 Small gear 7 Support shaft 8 Bearing means 9 Drive motor 13 Blower 14 Boiler device 16 Food chamber 18 Food chamber 20 Spiral fin 21 Internal space path 22 Dam plate

Claims (3)

  Dalai powder is fed to the upstream side of a horizontal drum that rotates at a fixed inclination angle, and the inside of the drum is formed as a hot air passage. Dalai powder passes through the drum from the upstream side to the downstream side in the process. A method for drying dairy powder characterized by removing water adhering to the powder to 100% and oil to about 60% to 80%.   The hot air temperature is high in the downstream side and low in the upstream side. Spiral fins are attached to the wall surface in the lengthwise direction in the horizontal drum, and appropriate intervals between adjacent fins are partitioned by a weir plate. 3. The dairy powder drying treatment method according to claim 1, wherein the dairy powder is transferred while being dropped.

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