WO2008020674A1

WO2008020674A1 - A centrifugal dehydrator

Info

Publication number: WO2008020674A1
Application number: PCT/KR2007/002075
Authority: WO
Inventors: Jae Sun Kim
Original assignee: Hwa Yang Machinery Co. Ltd
Priority date: 2006-08-16
Filing date: 2007-04-27
Publication date: 2008-02-21
Also published as: KR100688036B1

Abstract

The present invention is related to a centrifugal dehydrator for sludge extraction which does not use a coagulant. The centrifugal dehydrator of the present invention comprises a bowl having an inner surface in which at least one crush unit is disposed; and a screw conveyor disposed inside the bowl, and having a fan making a certain gap with the crush unit. The crush unit disposed above may be four (4) or eight (8), which may be disposed with a same space in the inner surface of the bowl, and the gap between the fan and the crush unit may be no more than 1mm. Also, the gap between the fan and the inner side of the bowl may be in the range of 1mm to 3mm.

Description

Description A CENTRIFUGAL DEHYDRATOR

[I] TECHNICAL FIELD

[2] The present invention relates to a centrifugal dehydrator for sludge extraction which does not use a coagulant. [3]

[4] BACKGROUND ART

[5] In a conventional sludge extracting method, generally, sludge produced from the process of treating foul water or waste water of livestock farming is inserted to a centrifugal separator in order to concentrate and dehydrate by physical centrifugal force. [6] A conventional centrifugal separator extracts sludge inserted by operation of a screw conveyor as illustrated in Korean Patent No. 407896. The centrifugal separator inserts sludge containing water and solid to a rotating bowl, and then separates the water and solid by applying centrifugal force with low power. During this process, specific coagulant is inserted to extract the sludge. [7] This process is illustrated in Fig. 1 in more detail. Motors are disposed on either side of the centrifugal separator, and a pulley connected to the motor is linked with the other pulley through a V belt. [8] Sludge inputted from a sludge input unit shown in the right side is transmitted through a pipe disposed inside the screw conveyor, and the sludge makes friction with an inner plate of the screw conveyor, and is extracted through holes of the screw conveyor. [9] During the above extraction process, separate chemicals such as coagulant should be added to increase cohesion of the sludge, whereby the operation becomes inefficient, and the sludge cannot be used as barnyard manure. [10]

[II] DISCLOSUREOFTHEINVENTION

[12] The present invention intends to solve the above problems of a conventional centrifugal separator. [13] Thus, one object of the present invention is to provide a centrifugal dehydrator comprising a bowl having an inner surface in which at least one crush unit is disposed; and a screw conveyor disposed inside the bowl and having a fan making a certain gap with the crush unit and the inner surface of the bowl. [14] Another object of the present invention is to provide a centrifugal dehydrator separating and extracting celluloid, optical fiber, sebum, etc., which are main components of sludge through a plurality of partitions by different specific gravities. [15] Another object of the present invention is to provide a centrifugal dehydrator having a bowl and a screw conveyor which are rotated with backlash, wherein the velocities of the bowl and the screw conveyor may be 2500-7000RPM.

[16] For achieving the above objects, the centrifugal dehydrator of the present invention comprises a bowl having an inner surface in which at least one crush unit is disposed; and a screw conveyor disposed inside the bowl, and having a fan making a certain gap with the crush unit. Here, four crush units may be disposed with a same space in the inner surface of the bowl, and the gap between the fan and the crush unit may be no more than lmm. Also, the gap between the fan and the inner surface of the bowl may be in the range of lmm to 3mm.

[17] A first screw shaft is connected to one end of the bowl, and a second screw shaft is connected to one end of the screw conveyor, wherein the screw conveyor includes a pipe acceptance part, and a pipe passing through the first screw shaft is accepted to the pipe acceptance part via slide connection.

[18] A first rotor shaft is connected to one end of the first screw shaft, and a first pulley is connected to one end of the first rotor shaft. A second rotor shaft is connected to one end of the second screw shaft, and a second pulley is connected to one end of the second rotor shaft. A power transmitted from the first pulley rotates the bowl, and a power transmitted from the second pulley rotates the screw conveyor.

[19] The first pulley is linked with a third pulley connected onto shaft of the first motor through a V belt, and the second pulley is linked with a fourth pulley connected onto shaft of the second motor through a V belt, wherein the first motor and the second motor rotate with backlash.

[20] A plate is formed in the center of the pipe acceptance part, and a projection part is protruded onto the front side of the plate, and a sludge extracted from an outlet of the pipe is guided to the projection part.

[21] A plurality of partitions are formed inside the pipe acceptance part, and a plurality of holes formed outside the partitions pass through the screw conveyor.

[22]

[23] EFFECT OF THE INVENTION

[24] Compared with the conventional centrifugal separator, the centrifugal hydrator according to the present invention can have the following advantages.

[25] First, the centrifugal dehydrator of the present invention comprises at least one crush unit disposed on an inner surface of a bowl, and the gap of between a fan of a screw conveyor and a crush unit is different from that of between a fan of the screw conveyor and the inner surface of the bowl. Thus, in case the bowl and the screw conveyor rotate, sludge particles may be separated and extracted by gravity differences, and the sludge particles may be crushed minutely by centrifugal force. [26] Second, the centrifugal dehydrator of the present invention does not need a separate coagulant. Thus, the present process is simpler, and can reduce environmental pollution by waste from using coagulant, and the present sludge may be used as a barnyard manure.

[27] Third, the centrifugal dehydrator of the present invention may set the percentage of water content of the sludge to 30% lower than that of the conventional sludge.

[28]

[29] BRIEF DESCRIPTION OF DRAWINGS

[30] The above and other objects, features and advantages of the present invention will become apparent from the following descriptions of preferred embodiments given in conjunction with the accompanying drawings, in which:

[31] Fig. 1 is a sectional view of a conventional centrifugal separator;

[32] Fig. 2 is a sectional view of a combined state of the centrifugal dehydrator according to one embodiment of the present invention;

[33] Fig. 3 is a sectional view of a disassembled state of the centrifugal dehydrator of Fig.

2 ;

[34] Fig. 4 is a side view of a first rotor shaft;

[35] Fig. 5 is a perspective view of the first rotor shaft;

[36] Fig. 6 is a side view of a second rotor shaft; and

[37] Fig. 7 is a perspective view of the second rotor shaft.

[38]

[39] BEST MODE FOR CARRYING OUT THE INVENTION

[40] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[41] Fig. 2 is a sectional view of a combined state of the centrifugal dehydrator according to one embodiment of the present invention.

[42] Referring to Fig. 2, a bowl 1 is inserted into a housing 5, and a screw conveyor 2 is combined into the bowl 1. At least one crush unit 14 is disposed on the inner surface of the bowl 1 according to the length direction of the bowl 1. The number of the crush unit 14 is not limited specifically, and four crush units 14 or eight crush units 14 may be disposed with a same space in the inner surface of the bowl 1.

[43] A gap exists between the crush unit 14 and a spiral fan 20 formed on the outer surface of screw conveyor 2, for example, no more than lmm. Also, the inner surface on which crush unit 14 is not disposed is gapped with the fan 20 of the screw conveyor 2. For example, the gap is in the range of lmm to 3mm.

[44] An enlarged view for the upper side of the bowl 1 illustrates the crush unit 14 disposed on the inner surface of the bowl 1.

[45] The screw conveyor 2 includes a pipe acceptance part 23, and a pipe 3 passing through the first screw shaft 12 is accepted to the pipe acceptance part 23 via a slide connection. [46] A plate 24 is formed in the center of the pipe acceptance part 23, and a projection part 25 is protruded onto the front side of the plate 24. [47] A sludge extracted from an outlet 31 of the pipe 3 is guided to the projection part 25, and makes friction with the projection part 25 as shown by arrow in Fig. 2. [48] Then, the screw conveyor 2 and bowl 1 make a backlash, and a centrifugal separating operation occurs, and by gravity differences, molecules having different gravities are guided to a plurality of partitions 26a and 26b. That is, during the centrifugal separating operation, each molecule in the sludge may be separated to celluloid whose gravity is light, optical fiber, sebum, grease oil, etc., and each molecule may be guided to different partitions 26a and 26b. According to one embodiment of the present invention, the velocities of the bowl 1 and the screw conveyor 2 may be

2500-7000RPM. [49] Then, the molecules are extracted from holes 27a, 27b and 27c passing through the screw conveyor 2. [50] And, the molecules are crushed minutely by the crush unit 14 and the fan 20 of the screw conveyor 2, and are extracted through an aperture 13. [51] Fig. 3 is a sectional view of a disassembled state of the centrifugal dehydrator of Fig.

2. [52] Referring to Fig. 3, a third pulley 43 and a fourth pulley 44 are connected to shaft of a first motor Ml and shaft of a second motor M2, respectively, and are linked with a first pulley 41 and a second pulley 42 connected to shafts of the bowl 1 and screw conveyor 2, respectively, through V belts 411 and 421. [53] A power supplied from the first motor Ml and the second motor M2 is transmitted to the first pulley 41 and the second pulley 42, respectively. [54] Fig. 4 is a side view of a first rotor shaft; and Fig. 5 is a perspective view of the first rotor shaft. [55] One end of the first rotor shaft 11 is connected to the first pulley 41, and the other end of the first rotor shaft 11 is connected to the first screw shaft 12, whereby a power transmitted from the first pulley 41 rotates the bowl 1. [56] Fig. 6 is a side view of a second rotor shaft; and Fig. 7 is a perspective view of the second rotor shaft. [57] One end of the second rotor shaft 21 is connected to the second pulley 42, and the other end of the second rotor shaft 21 is connected to the second screw shaft 22, whereby a power transmitted from the second pulley 42 rotates the screw conveyor 2. [58] [59] INDUSTRIAL APPLICABILITY [60] The above embodiments were described as preferred embodiments of the present invention. However, the scope of the present invention is not limited by the specific embodiments. Further, it should be understood by those skilled in the art that various changes and modifications can be made to this invention without departing from the scope and spirit of the present invention.

Claims

[ 1 ] L A centrifugal dehydrator comprising : a bowl having an inner surface in which at least one crush unit is disposed; and a screw conveyor disposed inside the bowl and having a fan making a certain gap with the crush unit.

[2] 2. The centrifugal dehydrator according to claim 1, wherein four crush units or eight crush units are disposed with a same space in the inner surface on the bowl.

[3] 3. The centrifugal dehydrator according to claim 1, wherein the gap between the fan and the crush unit is no more than lmm.

[4] 4. The centrifugal dehydrator according to claim 1, wherein the gap between the fan and the inner surface of the bowl is in the range of lmm to 3mm.

[5] 5. The centrifugal dehydrator according to claim 1, wherein a first screw shaft is connected to one end of the bowl, and a second screw shaft is connected to one end of the screw conveyor, wherein the screw conveyor comprises a pipe acceptance part, and wherein a pipe passing through the first screw shaft is accepted to the pipe acceptance part via a slide connection.

[6] 6. The centrifugal dehydrator according to claim 5, wherein a first rotor shaft is connected to one end of the first screw shaft, and a first pulley is connected to one end of the first rotor shaft, and a second rotor shaft is connected to one end of the second screw shaft, and a second pulley is connected to one end of the second rotor shaft, and wherein a power transmitted from the first pulley rotates the bowl, and a power transmitted from the second pulley rotates the screw conveyor.

[7] 7. The centrifugal dehydrator according to claim 6, wherein the first pulley is linked with a third pulley connected to shaft of a first motor through a V belt, and the second pulley is linked with a fourth pulley connected to shaft of a second motor through a V belt, wherein the first motor and the second motor rotates with backlash.

[8] 8. The centrifugal dehydrator according to claim 5, wherein a plate is formed in the center of the pipe acceptance part, and a projection part is protruded onto the front side of the plate, and a sludge extracted from an outlet of the pipe is guided to the projection part.

[9] 9. The centrifugal dehydrator according to claim 5, wherein a plurality of partitions are formed inside the pipe acceptance part, and a plurality of holes formed outside the partitions pass through the screw conveyor.