Abstract: A method of preparing a recycled polymer may include: preparing a mixed solvent including a first solvent and a second solvent and supplying the mixed solvent to each of a dissolution tank and a precipitation tank, supplying a composite resin to the dissolution tank and dissolving the resin to obtain a dissolved mixture, filtering the dissolved mixture to obtain a polymer solution, and supplying the polymer solution to the precipitation tank and performing recrystallization to obtain a precipitated mixture including a recycled polymer.

Abstract: A wearable helmet capable of recording a 3D sound, a 3D sound system using the same, and a method therefor. An exemplary embodiment of the present disclosure provides a wearable helmet capable of 3D sound recording, including: one or more microphones configured to collect surrounding sound sources; and an analog-to-digital converter configured to convert the sound sources collected through the at least one microphone into digital signals and to provide the digital signals to an external signal conversion device.

Abstract: An additive removal apparatus and a method for removal of an additive using the same are provided. The additive removal apparatus comprises a barrel including an inner space and having a polymer inlet on one side and a polymer outlet on the other side; a screw in the inner space of the barrel, which axially rotates; and a solvent discharge unit at one end portion of the barrel, wherein the barrel includes a swelling solvent inlet that is positioned between the polymer inlet and the polymer outlet and adjacent to the polymer inlet and a shrinking solvent inlet that is positioned between the polymer inlet and the polymer outlet and adjacent to the polymer outlet.

Abstract: A method for preparing a recycled polymer is provided. The method includes: bringing a recovered polymer containing an additive into contact with an impregnation solvent in an impregnation tank to obtain a slurry containing a swollen polymer and an eluate; separating the slurry into a solid mixture containing the swollen polymer and a liquid mixture containing the eluate in a solid-liquid separator; and obtaining a recycled polymer from the solid mixture and recovering the additive from the liquid mixture, wherein the impregnation solvent is a mixed solvent of two or more solvents.

Abstract: A wearable helmet capable of recording a 3D sound, a 3D sound system using the same, and a method therefor. An exemplary embodiment of the present disclosure provides a wearable helmet capable of 3D sound recording, including: one or more microphones configured to collect surrounding sound sources; and an analog-to-digital converter configured to convert the sound sources collected through the at least one microphone into digital signals and to provide the digital signals to an external signal conversion device.

Abstract: Provided is a method for preparing a recycled ABS resin including: preparing an extrusion feed including an acrylonitrile butadiene styrene (ABS) base resin including polyurethane and a metal carboxylic acid salt or a hydrate of the metal carboxylic acid salt, and supplying the extrusion feed to an extruder to perform a depolymerization reaction of the polyurethane and extrude the extrusion feed, wherein a master index (M) value satisfies 0.2?M?0.6.

Abstract: The present application relates to a distillation device. When a feedstock containing acetone and methanol is separated using a distillation device according to the present application, a methanol removal distillation column may be located at a position for easily separating methanol to solve a problem due to accumulation of methanol in the process and to lower the methanol content in the acetone product, and thus the lifetime of catalysts can be extended, and moreover, methanol can be removed with good efficiency from a flow of the lower part of the distillation column obtaining the final acetone product by using only the conventional phase separator and one methanol removal distillation column further installed, so that the acetone product obtained from the upper part of the distillation column obtaining the acetone product can be obtained in high purity and the operating cost and the equipment cost of equipments can be greatly reduced.

Abstract: The present application relates to a distillation device. When a feedstock containing acetone and methanol is separated using a distillation device according to the present application, a methanol removal distillation column may be located at a position for easily separating methanol to solve a problem due to accumulation of methanol in the process and to lower the methanol content in the acetone product, and thus the lifetime of catalysts can be extended, and moreover, methanol can be removed with good efficiency from a flow of the lower part of the distillation column obtaining the final acetone product by using only the conventional phase separator and one methanol removal distillation column further installed, so that the acetone product obtained from the upper part of the distillation column obtaining the acetone product can be obtained in high purity and the operating cost and the equipment cost of equipments can be greatly reduced.

Abstract: A speaker device for a vehicle includes a speaker unit, an enclosure mounted to a vehicle body accommodating the speaker unit, and provided with an inner space which is divided into a front space into which a front sound of the speaker unit is radiated and a rear space into which a rear sound of the speaker unit is radiated by a division member, a first path connecting the front space to a first division space provided in the vehicle body, a second path connecting the rear space to a second division space provided in the vehicle body, and a front sound outlet connecting the front space to an indoor space of the vehicle.

Abstract: A speaker device for a vehicle includes a speaker unit, an enclosure mounted to a vehicle body accommodating the speaker unit, and provided with an inner space which is divided into a front space into which a front sound of the speaker unit is radiated and a rear space into which a rear sound of the speaker unit is radiated by a division member, a first path connecting the front space to a first division space provided in the vehicle body, a second path connecting the rear space to a second division space provided in the vehicle body, and a front sound outlet connecting the front space to an indoor space of the vehicle.

Abstract: Provided are a method of and a device for purifying isopropyl alcohol. Water may be effectively removed from a feed including water and isopropyl alcohol while consuming a minimum amount of energy, and therefore, a high-purity isopropyl alcohol may be obtained.

Abstract: Provided are an apparatus and a method for preparing bisphenol A. In the present invention, all or some of a mother liquid stream is circulated to a flash rector through a bypass line after crystallization in a process of preparing bisphenol A so as to increase a conversion rate of bisphenol A in a reactor, reduce energy, and use a heating source of phenol to be discharged to an upper side of the flash reactor, and thus the reaction efficiency of the whole process can be increased.

Abstract: Provided are a method of and a device for purifying isopropyl alcohol. Water may be effectively removed from a feed including water and isopropyl alcohol while consuming a minimum amount of energy, and therefore, a high-purity isopropyl alcohol may be obtained.

Abstract: Provided are a method of and a device for purifying isopropyl alcohol. Water may be effectively removed from a feed including water and isopropyl alcohol by consumption of the minimum amount of energy, and therefore, a high purity isopropyl alcohol may be obtained.

Abstract: Provided are a method of and a device for purifying isopropyl alcohol. Water may be effectively removed from a feed including water and isopropyl alcohol while consuming a minimum amount of energy, and therefore high-purity isopropyl alcohol may be obtained.

Abstract: Provided are an apparatus and a method for preparing bisphenol A. In the present invention, all or some of a mother liquid stream is circulated to a flash rector through a bypass line after crystallization in a process of preparing bisphenol A so as to increase a conversion rate of bisphenol A in a reactor, reduce energy, and use a heating source of phenol to be discharged to an upper side of the flash reactor, and thus the reaction efficiency of the whole process can be increased.

Abstract: Discloses is a disk for a horn of a vehicle. The disk of the horn has a shape in which the whole region of the disk is divided into a plurality of regions having different vibration characteristics and has a structure in which the plurality of regions are disposed along a circumferential direction of the disk.

Abstract: Discloses is a disk for a horn of a vehicle. The disk of the horn has a shape in which the whole region of the disk is divided into a plurality of regions having different vibration characteristics and has a structure in which the plurality of regions are disposed along a circumferential direction of the disk.

Abstract: The present invention relates to a method for purifying terephthalaldehyde which comprises a first step of dissolving terephthalaldehyde containing impurities in an aromatic solvent at high temperature to prepare a solution; and a second step of quenching the solution to re-crystallize it into terephthalaldehyde. In accordance with the present invention, high pure terephthalaldehyde may be economically prepared.

Abstract: The present invention relates to a method for preparing an aromatic dialdehyde, comprising, a) a step of gas phase oxidation reaction for preparing aromatic dialdehyde from dimethyl benzene; b) a step of separation for selectively recovering crude aromatic dialdehyde of molten phase from the reaction product of the step (a); and c) a step of purification for obtaining highly pure aromatic dialdehyde by purifying said crude aromatic dialdehyde, and a manufacturing system used for the preparation method. The method for preparation of the aromatic dialdehyde according to the present invention is simple, effective, and advantageous in that highly pure aromatic dialdehyde can be continuously prepared.