WO2004052792A1

WO2004052792A1 - Waste-water filter, waste-water treatment device and method incorporating the waste-water filter

Info

Publication number: WO2004052792A1
Application number: PCT/KR2003/002676
Authority: WO
Inventors: Ju-Hwan Kim
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-12-06
Filing date: 2003-12-06
Publication date: 2004-06-24
Anticipated expiration: 2005-06-06
Also published as: AU2003302915A1; KR100381297B1

Abstract

The present invention provides a device and a apparatus for filtering waste-water and a method using the same, and a apparatus for filtering spectacles lens grinding water employing the same. The device for filtering waste-water comprises: a fiber filter (60); and a vacuum filtering tub (50) imbedded with the fiber filter and into which waste water flows, discharging filtered water and dirt separately; wherein only liquid water passes through ultra-fine pores formed on the fiber (60) while an inside of the vacuum filtering tub (50) maintained to be a vacuum with a drawing pressure so as to filter the waste-water. The apparatus for filtering waste-water having the device comprises: the device for filtering waste-water (1a); a valve means (80) connected with the dirt discharging port (20) and the air drawing port (40) of the vacuum filtering tub (50) used for drawing air and discharging filtered dirt and an air/dirt drawing means (100) connected to the valve means (80), used for vacuumizing the inside and discharging the filtered dirt. The apparatus for filtering spectacles lens grinding water using apparatus comprises: an apparatus (1b) including a clean-water storing tub (110) having a pump (130), and a dirt collecting tub (120); and a spectacles lens grinding device (220) disposed over an accommodating means (210), and having a clean-water supply pipe (140) connected with a clean-water storing tub (110), and a grinding water drain pipe (150) as to drain the grinding water generated while the spectacles lens is being grinded. According to the present invention, as the ultra-fine pores are formed by the drawing pressure applied during the inner vacuum state, and through which only the pure water in the waste-water passes and the solid dirt in the waste-water is filtered, and therefore, the improved effect is achieved the water pollution and floating substances are prevented by a simple construction effectively, and the filtered and collected dirt can be reused to contribute to the recycle of the resource.

Description

WASTE-WATER FILTER, WASTE- WATER TREATMENT DEVICE AND METHOD INCORPORATING THE WASTE- WATER FILTER

FIELD OF THE INVENTION The present invention relates to a filtering device for filtering waste water such as grinding water, a waste-water filtering apparatus and a method of using the same, and a spectacles lens grinding water filtering apparatus employing the same, and more particularly, to a filtering device for filtering waste water such as grinding water, a waste-water filtering apparatus and a method using the same, and a spectacles lens grinding water filtering apparatus employing the same, with which water pollution caused by heavy metal component and floating substance included in discharged waste water is effectively prevented as the efficiency to filter the waste water is enhanced rapidly with a simple construction as well as the filtered and collected dirt such as the grinding powder or the like is recycled so that the resources can be reused.

BACKGROUND OF THE INVENTION

The waste water such as the grinding water that includes impurities, heavy metal component, floating substances, etc. used as the lubricating water in grinding a material such as a spectacles lens is generally filtered by a filter, and then the water is circulated and reused. Environment pollution such as water pollution may be caused if the waste water is discharged as it is through a drain pipe, so the waste water has to be filtered properly.

The conventional filtering apparatus for filtering the waste water filters the waste water by pressing the waste water such as the grinding water with a pump or dropping the waste-water naturally by the gravity in the filtering apparatus so that the waste-water pass through a filtering member in the filtering apparatus. Most of such conventional filtering members filter the waste water through the pores formed previously during the manufacturing process thereof.

However, in such a conventional filtering apparatus, it is almost impossible to form the ultra-fine pores on the filter itself while the filter is being manufactured. Therefore, the fine dirt smaller than the pores formed on the filter cannot be filtered perfectly when the waste water such as the grinding water is filtered, and the efficiency to filter the waste- water is low as the fine dirt is adhered to the fine pores of the filtering member.

If the waste water is pressed to pass through the filter in the conventional filtering apparatus, the pores may be enlarged, by which the filtering efficiency is lowered even through the filtering time is shortened. And, if the waste water is filtered by the natural dropping manner, the time for filtering the waste water becomes too great. Thus, if such a conventional filtering apparatus is used, the waste water is not filtered perfectly, which results in the reuse of the filtered water containing a certain amount of impurities such as the grinding powder, heavy metal component, and floating substances in the grinding operation or the like, thereby causing the rapid lowering of the filtering efficiency.

Meanwhile, a fiber filter that filters the dirt or the like in air has been proposed, which has ultra-fine pores that pass the air and filter the foreign substances such as dirt in the air.

However, such a fiber filter has not been used for filtering the waste water such as the grinding water including the grinding powder. In particular, the filtering apparatus with the fiber filter and the waste-water filtering apparatus have not been proposed, in which the fiber filter is equipped in the vacuum filtering tub and the liquid state pure water in the turbid grinding water passes through the ultra-fine pores formed by the drawing pressure applied to the fiber filter when the vacuum filtering tub is vacuumized and the solid state impurities, heavy metal component, floating substance or the like greater than the ultra-fine pores formed by the vacuumization is filtered perfectly, whereby the waste water is filtered rapidly and efficiently.

The present invention has been proposed to overcome the above-described problems, and it is an object of the present invention to provide a filtering apparatus that the filtering 5 member including the fiber filter is disposed in the vacuum filtering tub, the liquid state pure water passes through the ultra-fine pores formed by the drawing pressure applied to the fiber filter by the vacuum state of the vacuum filtering tub and the solid state impurities are filtered by the fiber filter, whereby the waste-water is filtered rapidly and perfectly.

Another object of the present invention is to provide waste-water filtering method o and apparatus having the waste-water filtering device, in which the fiber filter is equipped to provide the simple construction of the apparatus and increase the efficiency of filtering the waste water such as the grinding water, and in particular, the water pollution caused by the discharge of the waste water is prevented in advance by the perfect filtering of the waste water, and the filtered impurities such as the grinding powder is collected simply and reused5 easily.

Still another object of the present invention is to provide a spectacles lens grinding water filtering apparatus with the convenient and practical waste-water filtering apparatus, in which the grinding water generated by the grinding of the spectacles lens is effectively filtered by the waste-water filtering apparatus and the filtered clean-water is circulated to be o used for grinding the spectacles lens again, by which the amount of water consumed for the grinding water is reduced to preserve the water resources and the water pollution caused by the discharge of grinding water is prevented by the superior filtering performance to filter the heavy metal component such as lead generated by the grinding of the spectacles lens.

5 DETAILED DESCRIPTION OF THE INVENTION To achieve the above object, according to one aspect of the present invention, there is provided a waste-water filtering device comprising: a fiber filter; and a vacuum filtering tub that is imbedded with the fiber filter and into which waste water flows, the vacuum filtering tub for discharging filtered clean water and filtered dirt separately; wherein only liquid state water passes through ultra-fine pores formed on the filter fiber while an inside of the vacuum filtering tub is maintained to a vacuum state with a drawing pressure applied to the filter fiber so as to filter the waste water.

According to another aspect of the present invention, there is provided a waste- water filtering apparatus with a waste-water filtering device, the apparatus comprising: a vacuum filtering tub having a waste-water inflow port, a dirt discharge port, a clean-water discharge port that is covered by a covering member at a vacuum state of inside and discharges filtered pure water, and an air drawing port used for vacuumizing the inside; a fiber filter disposed in the vacuum filtering tub between the dirt discharge port and the air drawing port, the fiber filter by which only liquid state water passes through ultra-fine pores formed by drawing pressure while an inner vacuum state of the vacuum filtering tub is maintained; a valve means connected with the dirt discharging port and the air drawing port of the vacuum filtering tub, the valve means being used for drawing air and discharging filtered dirt outside the vacuum filtering tub; and an air/dirt drawing means connected to the valve means, the air/dirt drawing means being used for vacuumizing the inside of the vacuum filtering tub by drawing air out of the vacuum filtering tub and for discharging the filtered dirt.

According to still another aspect of the present invention, there is provided a method for filtering waste water with the waste-water filtering apparatus as depicted in claim 7, the method comprising: a valve operating step for closing a dirt discharge port of a vacuum filtering tub and opening an air drawing port of the vacuum filtering tub by operating a valve means; a waste-water inflow step that the waste-water flows through the waste-water inflow port of the vacuum filtering tub onto a filtering member in the vacuum filtering tub, the filtering member including a fiber filter; a waste-water filtering step for filtering the waste water so that solid state dirt in the waste water is filtered and liquid state pure water passed through ultra-fine pores formed on a the fiber filter by a drawing pressure applied to the fiber filter while a lower part of the fiber filter of the filtering member in the vacuum filtering tub is vacuumized as an air/dirt drawing means connected with an air drawing port of the vacuum filtering tub via the valve means operates; and a clean-water and dirt collecting step that the filtered clean water is discharged through the lower Ω discharge port of the vacuum filtering tub and the dirt filtered by the filtering member is collected in a collecting tub via the dirt drawing means through the discharge port as the valve means is operated.

Finally, according to still another aspect of the present invention, there is provided an apparatus for filtering spectacles lens grinding water comprising: a waste- water filtering apparatus as depicted in claim 7; a means for accommodating the waste- water filtering apparatus; and a spectacles lens grinding device disposed over the accommodating means, and having a clean-water supply pipe so connected with a clean- water storing tub of the waste water filtering apparatus as to supply clean water while a spectacles lens is being grinded, and a grinding water drain pipe so connected with the vacuum filtering tub of the waste-water filtering apparatus as to drain the grinding water generated while the spectacles lens is being grinded, whereby water pollution caused by the grinding water is prevented.

BREIF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the waste-water filtering apparatus according to the present invention; FIG. 2 is a plan view of the waste-water filtering apparatus according to the present invention;

FIG. 3 is a frontal view of the waste-water filtering apparatus according to the present invention; FIG. 4 is a schematic view of the vacuum filtering tub of the waste-water filtering apparatus according to the present invention;

FIG. 5 is an exploded perspective view of the vacuum filtering tub of the waste- water filtering apparatus according to the present invention;

FIG. 6 is an exploded perspective view of the filtering member employed in the waste-water filtering apparatus according to the present invention;

FIG. 7 is an exploded perspective view of the valve means employed in the waste- water filtering apparatus according to the present invention;

FIG. 8 shows the air drawing means in the waste-water filtering apparatus according to the present invention, in which FIG. 8 a is a partially cutaway perspective view and FIG. 8b is a plan view; and

FIG. 9 is a perspective view showing the overall construction of the spectacles lens grinding water filtering apparatus employing the waste-water filtering apparatus according to the present invention.

<Description of the reference numerals of the main parts in the drawings> la .... Filtering device lb .... Waste-water filtering apparatus

10 .... Waste- water inflow port 20 .... Dirt discharge port

30 .... Clean- water discharge port 40 .... Air drawing port

50 .... Vacuum filtering tub 60 .... Fiber filter

70 .... Filtering member 80 .... Valve means 100 .... Air drawing means 110 .... Clean- water storing tub 120 .. Dirt collecting tub 130 .... Pump 140 .. Clean- water supply pipe 150 .... Waste-water discharge pipe 200 .. Spectacles lens grinding water filtering apparatus 210 .. Waste-water filtering apparatus accommodating means 220 .. Spectacles lens grinding apparatus 230 ... Controller

PREFERRED EMBODIMENT OF THE INVENTION Hereinbelow, the present invention will be described in greater detail with reference to the accompanying drawings.

FIG. 1 shows the overall construction of the waste-water filtering device la according to the present invention. The filtering device la of the present invention is mainly comprised of a fiber filter 60, and a vacuum filtering tub 50 imbedded with the fiber filter 60 to filter the waste water such as the grinding water including the grinding powder used for the lubrication during the grinding of the spectacles lens and divide the waste water into the clean-water passing through the fiber filter 60 and dirt such as grinding powder, and discharge the clean-water and the dirt separately outside.

The characteristics of the constitution of the filtering device la of the present invention to filter the waste- water is as follows: The waste-water such as turbid water flowing into the vacuum filtering tub 50, in which the dirt such as the grinding water and the inflow water are mixed, reaches the fiber filter 60. As the lower area of the fiber filter 60 is vacuumized by drawing the air inside the vacuum filtering tub 50, more particularly, the air at the inside of the vacuum filtering tub 50, ultra-fine pores are formed on the fiber filter 60 by the drawing pressure applied to the fiber filter 60. Thus, only the liquid state pure water passes through the ultra-fine pores by the drawing pressure, and only the fine particles that is the solid state dirt such as the grinding powder or the heavy metal component such as lead of which size is greater than the ultra-fine pores are not passed through the ultra-fine pores of the fiber filter 60 so as to be filtered.

Meanwhile, the constitution of the vacuum filtering tub 50 in the waste-water 5 filtering device la of the present invention is as follows: As shown in FIG. 1, it is comprised of an inflow port 10 through which the waste water flows in, a discharge port 20 for discharging the dirt filtered by the fiber filter 60 outside, a clean-water discharge port 30 that has a cover plate 32 closed by the vacuumization of the inside and discharges clean water that is the pure water from which the dirt has been filtered by the fiber filter 60, and 0 an air drawing port 40 for drawing the inside air to vacuumize the inside of the vacuum filtering tub 50.

Accordingly, the waste-water F flows in through the waste-water inflow port 10 formed at the upper part of the vacuum filtering tub 50, and the waste-water F is filled up on the fiber filter 60 that is not formed with the ultra-fine pores at all. In such a situation, the 5 dirt discharge port 30 is in closed state.

As the lower area of the fiber filter 60 is vacuumized by the drawing of air in the vacuum filtering tub 50 through the air drawing port 40 toward the lower side of the fiber filter 60 of the vacuum filtering tub 50, only the pure water W among the waste-water passes through the ultra-fine pores formed by the drawing pressure applied to the fiber filter - 0 60 and the residuary dirt such as the grinding powder is filtered by the fiber filter 60. The dirt T filtered as above is discharged through the dirt discharge port 20, by which the filtering of waste water with the filtering device la of the present invention is performed.

In such a situation, as shown in FIG. 1 as the sectional view of the main part, the fiber filter 60 is comprised of a multilayer fiber filter in which a High Efficiency

^:5 Performance Airfilter medium 62(Hereinbelow, referred to as HAPA medium.), a lypore medium 64, and a polyester foam 66 are piled up. The HAPA medium 62, the lypore medium 64 and polyester foam 66 axe fiber filter materials that are sold commercially in the market.

The reason that the fiber filter 60 is formed as the multilayer in the filtering device la as above is to elongate the life of the fiber filter 60. The fiber filter 60 in which the three fiber filters are piled up has the density of about 32 ib/it , the extension strength of 450 psi, and the tensile strength of 315%, and can be used for more than one month. As shown in FIG. 1, the fiber filter layers 62, 64 and 66 are protected by being enclosed with polyester foam 60a, wherein the lypore medium 64 and the HAPA medium 62 are preferably piled up on the upper and lower side of the dual polyester foam 66, respectively, and in such a case, the fiber filter 60 can be turned upside down after it has been used for some period of time.

Meanwhile, the detailed filtering function of the fiber filter 60 is as follows. The vacuum filtering tub 50 is formed to have the diameter of 10cm and the height of 17cm. The fiber filter 60 has the diameter of 10cm. In such a status, the air in the vacuum filtering tub 50, more particularly, at the lower area of the fiber filter 60 of the vacuum filtering tub 50 is drawn outside to be vacuumized, whereby the drawing pressure of more than 25mmAq, preferably of 25-50mmAq, is applied to the fiber filter 60 to form the ultra- fine pores of 0.01 m-0.12 m on the fiber filter 60. Only the liquid state pure water can pass through the ultra-fine pores, and the solid state dirt such as the grounding powder, the heavy metal component such as lead, and the floating substances do not pass through the ultra-fine pores and are filtered by the fiber filter 60.

In that situation, the ultra-fine pores can be formed as the drawing pressure greater than 25mmAq is applied to the fiber filter 60 in the case of the vacuum filtering tub 50 having the size described above, however, the ultra-fine pores may be to great and the life may be shortened if the drawing pressure is excessive to be greater than 50mmAq through which the dirt may pass through, so it is preferable that the drawing pressure is maintained to the range of 25-50mmAq.

However, if the vacuum filtering tub 50 becomes great and the fiber filter 60 becomes great and thick, the drawing pressure has to be adjusted according to the increasing size. However, the fiber filter 60 is not formed with the ultra-fme pores at all while the drawing pressure is not applied, so the filtering performance can be maintained constant as the size of the ultra-fme pores does not increase abruptly even with the increase of the size of the vacuum filtering tub 50 and the increase of the pressure.

Meanwhile, the examples of the substances having the size smaller than the ultra- fine pores of the range of 0.01/tm-0.12 m are merely the gas molecules, smoke, virus, etc., however, most of the dirt, heavy metal component and floating substances included in the waste water is greater than the above range. Thus, they can be filtered by the fiber filter 60 perfectly as the ultra-fine pores are formed by the drawing pressure applied to the fiber filter 60. In other words, the waste-water is filled up on the fiber filter 60 as the ultra-file pores are not formed at all while the fiber filter 60 is not applied with the drawing pressure, that is, while the lower area of the fiber filter 60 in the vacuum filtering tub 50 is not vacuumized. To the contrary, the waste water is filtered by the ultra-fine pores of the fiber filter 60 during the vacuum state. In other words, most of the conventional filtering members used in filtering the waste water are installed in a casing and then perform the filtering while the waste water is pressed from the upside by a pump or is dropped by the natural gravity to pass through the pores. However, there has not been proposed the waste-water filtering device la that the waste water is filled up on the fiber filter 60 having no ultra-fme pores as the waste water is initially flows into the vacuum filtering tub 50 and the dirt such as the grounding powder, heavy metal component, and floating substance in the waste-water is perfectly filtered by the ultra- fine pores formed when the drawing pressure is applied.

Meanwhile, as shown in FIG. 1 , it is preferable that the filtering member 70 capable of extending the life of the fiber filter 60 and previously filtering the dirt greater than the fiber filter 60 is employed, and such a filtering member 70 is included in the fiber filter 60. That is, as shown in FIG. 1, the filtering member 70 installed in the vacuum filtering tub 50 of the waste-water filtering device la can be installed in the casing member 76 by which a screen net 72, a space mat filter 74, and the fiber filter 60 are fixed in the vacuum filtering tub 50. In such a situation, the screen net 72 and the space mat filter 74 function to filter the great dirt among the foreign substances consecutively, which improves the filtering performance and extends the life of the fiber filter 60. Further, the life of the fiber filer 60 is extended even when the fiber filter 60 is used as being turned over.

The waste-water filtering device 1 a of the present invention can be used for the filtering of the waste water including the dirt such as the grounding powder that has been used in the grinding of spectacles, heavy metal component, and floating substances, as well as for the secondary filtering of the waste water such as the lubricating water used for the various appliances in the industries or the waste water processed by the biological processing method. In such a case, it is sufficient if only the size of the vacuum filtering fiber 50 of the present invention, the fiber filter 60 installed therein, and the filtering member including it is adjusted.

Accordingly, the waste-water filtering device 1 a of the present invention provides the effects that it can filter the dirt such as the heavy metal component, the grinding powder, or floating substances perfectly by the fiber filter 60 formed with the ultra-fine pores and the filtering member 70 enclosing it as the drawing pressure is applied to the fiber filter 60 by vacuumizing the inside of the vacuum filtering tub 50 by drawing air in the vacuum filtering tub 50 through the air drawing port 40 while the vacuum filtering tub 50 is installed at an arbitrary place that generates the waste water and the filtering member 70 including the fiber filter 60 is installed therein.

Next, FIGS. 2 and 3 show the waste-water filtering apparatus lb of the present invention. The waste-water filtering apparatus lb of the present invention basically has the waste-water filtering device la, and additionally has a valve means 80 connected with the dirt discharge port 20 and the air drawing port 40 of the vacuum filtering tub 50 so as to make it possible to draw air and dirt by turns, an air/dirt drawing means 100 connected with the valve means 80 to draw air and discharge dirt, a clean- water storing tub 110, and a dirt collecting tub 120. The detailed constitution of such elements is as follows.

At first, as shown in FIGS. 2 and 3, the clean- water storing tub 110 and the dirt collecting tub 120 at the side thereof are attached and fixed integrally, and the vacuum filtering tub 50, a valve means 80, and air and dirt drawing means 100 are disposed in the clean- water storing tub 110, and a pump 130 is additionally installed on the clean- water storing tub 110. A washing- water drain pipe for washing the ventilation ports and the inside, which are not designated by reference numerals in the figure, are respectively installed in the storing tub 110 and collecting tub 120.

Next, FIGS. 4 and 5 show the vacuum filtering tub 50 used in the waste-water filtering apparatus lb of the present invention. The vacuum filtering tub 50 is mainly comprised of a lower casing 52 and an upper casing 54. A casing 76 of the filtering member 70 that will be described below is screwedly assembled between the upper and lower casings 54 and 53.

In other words, the lower casing 52 is integrally formed with a clean-water discharge port 30 at the lower portion thereof and a fixing portion 55a fixed through the clean-water inflow port 112 of the clean- water storing tub 110 at the outside thereof, and a cover 32 for vacuumizing the vacuum filtering tub 50 automatically by being pulled by the drawing of air is installed at the clean-water discharge port 30 of the lower casing 52.

In such a situation, as shown in FIG. 5, the cover 32 is disposed at the clean-water discharge port 30 of the lower casing 52 while a fixing bolt 32c assembled with the fixing member 32b at an end thereof is assembled with the fixing plate 32a fixed at the clean-water discharge port 30 of the lower casing 52. An extended portion 55b inserted into the clean- water storing tub 110 is integrally formed at the fixing portion 55a of the lower casing 52.

Next, as shown in FIGS. 4 and 5, the waste- water inflow port 10 is integrally formed on the upper part of the upper casing 54, and the dirt discharge port 20 is integrally formed on a side thereof. Screw portions 54a and 52a screwed with the screw portions 77a and

77b formed on the upper and lower portions of the casing 76 of the filtering member 70 are integrally formed on the lower and upper inner circumferences of the upper and the lower casings 54 and 52.

As shown in FIG. 4, it is preferable that a nozzle head 59 connected with the dirt discharge port 20 for discharging the dirt such as the grinding powder filtered on the filtering member 70 outside easily is arranged at the upper side of the filtering member 70.

A plurality of drawing nozzles 59a are installed downward of which lengths reach uniformly in the cylindrical vacuum filtering tub 50.

Accordingly, the vacuum filtering tub 50 used in the waste-water filtering apparatus lb of the present invention is assembled upward and downward with the casing 76 of the filtering member 70 at the middle position thereof, and the fixing portion 55a of the casing 52 is fixed and installed on the inflow port 112 of the clean- water storing tub 110.

In such a situation, the dirt discharge port 20 and the air drawing port 40 are connected with a dirt discharge pipe 82 and an air drawing pipe 84 that are respectively connected with the valve means 80 which will be described later. Accordingly, in the waste-water filtering apparatus 1 of the present invention, the valve means 80 closes the dirt discharge port 82 when the waste-water initially flows in through the waste-water inflow port 10. As the air in the lower casing 52 at the lower part of the fiber filter 60 is drawn through the air drawing pipe 84 by the operation of the valve means 80, the cover 32 is closed to make a vacuum state. Then, the drawing pressure is applied to the fiber filter 60 in the filtering member 70 to form the ultra-fine pores, and the filtered pure water, that is, the clean water, opens the cover 32 by the dropping force thereof so that the clean water flows into the clean- water storing tub 110 at the lower side.

In such a situation, the filtered water, that is, the clean water, that has passes through the fiber filter 60 flows through the gap between the cover 32 and the clean-water discharge port 30 of the lower casing 52 of the vacuum filtering tub while it flows to the cover 32 during the drawing of the air through the air drawing port 40. Then, the clean- water continuously closes the gap to maintain the vacuum state, and the clean water is dropped through the clean-water discharge port 30 and then flows into the clean- water storing tub 10 as the inner pressure is removed when the air drawing is stopped.

Next, as the air drawing pipe 84 is closed and the dirt discharge pipe 82 is opened by the operation of the valve means 80 so as to draw air, the dirt remaining on the filtering member 70 is collected in the dirt collecting tub 120 through the dirt discharge pipe 82, the valve means 80, and the dirt drawing means 100. In this situation, the dirt, floating substances, on the filtering member 70 is drawn and collected smoothly with the help of the nozzle head 50.

Meanwhile, as shown in FIG. 5, a screen net 56 having the shape of a cone for filtering the great dirt included in the waste water is disposed in the upper casing 54 of the vacuum filtering tub 50 of the waste-water filtering apparatus lb according to the present invention, and a partitioning wall 58 for preventing the reflow of clean water that has passed through the filtering member 70 by the drawing of air is integrally formed at the air drawing port 40 in the lower casing 52.

Next, FIGS. 4 and 6 show the filtering member 70 of the waste- water filtering apparatus lb of the present invention. As described above, the casing 76 of the filtering member 70 of the present invention is comprised of a lower casing and an upper casing 76a and 76b that are attached to and detached from each other and are imbedded with more than one layer of the screen net 72, space mat filter 74 and fiber filter 60 of filtering member 70 piled up on each other therein.

In other words, as shown in FIG. 6, the upper and lower casings 76a and 76b are formed integrally with a protruding portion 79a that protrudes between the upper and the lower casings 54 and 52 of the vacuum filtering tub 50, the screw portions 77a and 77b screwed with the screw portions 54a and 54b of the casings 54 and 52 of the vacuum filtering tub, and apertures 78a and 78b through which the waste-water and water pass, whereby the great dirt in the waste- water is filtered. The protruding portions 79a and 79b of the casing 76 of the filtering member are formed integrally with the screw portions 75a and 75b that are assembled with each other. Since the casings of the filtering member 70 can be attached to and detached from each other, the screen net 72, the space mat filer 74, and the fiber filter 60 in the filtering member 70 can be exchanged easily with new ones. Therefore, the user disassemble or assemble the upper and lower casings 54 and 52 of the vacuum filtering tub 50 with the casings 76a and 76b of the filtering member 70 respectively, and detaches the casings 76a and 76b of the filtering member if he needs to exchange the screen net 72, the space mat filter 74 and the fiber filter 60 with new ones, which makes it convenient to use the waste-water filtering apparatus lb of the present invention. Next, FIGS. 2 and 7 show the valve means 80 of the waste-water filtering apparatus 1 of the present invention. The valve means 80 is one of the characteristics of the waste- water filtering apparatus lb of the present invention. The conventional valves have the problem that the valving operation thereof is not performed smoothly as the dirt, the fine powders such as the grounding powder, generated during the filtering of the waste-water permeates into the valve. Therefore, the present invention proposes the valve means 80 that passes the fine dirt such as the grinding powder and operates smoothly.

Particularly, the valve means 80 is comprised of a casing 86, a rotating member 90 and a cover 92, of which detailed construction is as follows.

As shown in FIGS. 2 and 7, the casing 86 is vacant and is connected with the dirt discharge pipe 82 connected with the dirt discharge port 20 of the vacuum filtering tub 50 along the circumference thereof. Further, the casing 86 is formed integrally with dirt and air inflow ports 86a and 86b that are connected to the air drawing pipe 84 at the opposite sides thereof, respectively, and is formed integrally with the air drawing port 86c connected with a connection pipe 104 that are described later, at the central area thereof.

A rotating member 90 is installed at the inside of the casing 86 and is rotated by a motor 88. The rotating member 90 has closing members 90a and 90b for opening/closing the inflow ports 86a and 86b while the motor is operating. A lid 92 is fixed on the upper side of the casing 86 via a sealing 95 and fixed thereon airtightly.

In greater detail, as shown in FIG. 7, the motor 88 is accommodated in the accommodating portion 89b formed on the casing 86 and the driving shaft 94b thereof is inserted to and held by the holding bar 92a of the lid 92. And, a driving gear 94b engaged with a driven gear part 96b formed integrally with a side of the rotating member 90 is installed on the driving shaft 94b, and the a vertical shaft 96a inserted to and held by a holding recess 89a and holding bar 92a of the casing 86 and the lid 92 is installed on a side of the driven gear part of the rotating member 90.

Accordingly, as shown in FIG. 7, as the motor 88 operates to rotate the driving gear 94a in a clockwise direction, the rotating member 90 formed on the driven gear part 96b engaged with it is rotated in a counterclockwise direction around the vertical shaft 96a so that the dirt inflow port 86a of the casing 86 is closed by one closing member 90a. And consequently, as the air drawing means 100 that will be described later operates, the air in the vacuum filtering tub 50 is drawn through the air drawing port 86c of the valve means 80, the air inflow port 86b, and the air discharge port 40 of the vacuum filtering tub 50, whereby the lower area of the filtering member 70 of the vacuum filtering tub 50 is vacuumized. As the fiber filter 60 in the filtering member 70 is applied with the drawing pressure of about 25mmAq, the ultra-fine pores are formed on the fiber filter 60, whereby the filtering of the waste water is performed as describe above.

Next, as the motor 88 of the valve means 80 is rotated reversely, the rotating member 90 rotates reversely so that the other closing member 90b closes the air drawing port 86b, and consequently, the dirt such as the grinding powder remaining on the filtering member 70 of the vacuum filtering tub 50 moves through the discharge pipe 82, and the dirt inflow port 86a and the air drawing port 86c of the casing 86 of the valve means 80, and then is collected in the collecting tub 120 through the drain pipe 104 by the air drawing means 100 that will be described later. In such a situation, fixing bars 87a and 87b assembled by the fixing bolts 87 are respectively formed on the lid 92 and the casing 86 of the valve means 80 of the present invention, and a rubber blocking membranes 97a and 97b for blocking the movement of the dirt such as the fine grinding powder toward the motor 88 while they are overlapped on each other near the driven gear 96b of the rotating member 90 are installed on the central area of the lid 92 and the casing 86. Next, FIG. 8 shows the air and dirt drawing means 100 of the waste-water filtering apparatus lb of the present invention. The air drawing means 100 of the present invention is comprised of a casing 106 connected with the connection pipe 104 that is connected with the air drawing port 86c of the valve means 80 at a side thereof and connected with the drain pipe 102 that is connected with the dirt collecting tub 120 at the other side thereof, and a drawing fan 108 installed in the casing 106 and rotated by the motor 108a installed in the casing 106.

Accordingly, the driving fan 108 is rotated as the motor 108a operates, and consequently, the air is discharged outside as the air in the vacuum filtering tub 50 is drawn by the operation of the valve means 80 and the dirt is discharged into the dirt collecting tub

120 through the drain pipe 102 as the dirt is drawn. In such a situation, it is preferable that the power of the motor 108a is adjusted to 80-150 watt.

In that situation, if the power of the motor 108a is lower than 80 watt, the drawing pressure applied to the fiber filter 60 becomes too small, and the waste-water is hardly filtered through the fiber filter 60. Meanwhile, if the power of the motor is greater than

150 watt, the power becomes greater than needed and too much electrical power is consumed, and the life of the filter is shortened since the fiber filter 60 is applied with the drawing pressure greater than needed. Moreover, the ultra-fine pores formed on the fiber filter 60 becomes too great, and the great dirt may pass through the ultra-fine pores, by which the waste-water filtering efficiency is lowered.

Next, the filtermg process performed by the waste-water filtering apparatus lb having he waste-water filtering device la of the present invention is described with reference to FIGS. 2 through 8. At first, the valve operating step is performed in which the valve means 80 is operated to close the dirt discharge port 20 of the vacuum filtering tub 50, and to open the air drawing port 10 of the vacuum filtering tub 50. Then, a waste- water inflow step is performed in which the waste-water flows onto the filtering member 70 including the fiber filter 60 in the vacuum filtering tub 50 through the waste-water inflow port 10 of the vacuum filtering tub 50.

Next, the air and dirt drawing means 100 connected with the air drawing port 40 of the vacuum filtering tub 50 via the valve means 80 begins to operate to vacuumize the lower area of the filtering member 70 in the vacuum filtering tub 50, by which the waste-water filtering step is performed in which the waste water is filtered by passing only the pure water in the waste water through the ultra-fine pores formed by the drawing pressure applied on the fiber filter 60. Finally, the. filtered clean water is discharged through the lower discharge port 30 of the vacuum filtering tub 50, and the dirt on the filtering member

70 is discharged by the operation of the valve means 80 toward the dirt collecting tub 120 through the dirt discharge port 20 by the dirt drawing means 100, which is the step for discharging the dirt, by which the filtering of the waste water such as the grinding water is completed. Next, FIG. 9 shows the spectacles lens grinding water filtering apparatus 200 using the waste-water filtering apparatus lb of the present invention. The spectacles lens grinding water filtering apparatus 200 of the present invention is comprised the waste- water filtering apparatus lb, an accommodating means 210 for accommodating the waste- water filtering apparatus lb, a clean- water supply pipe 140 connected with the clean- water storing tub 110 of the waste-water filtering apparatus lb to provide the clean water during the grinding of the spectacles lens, and a spectacles lens grinding device 220 having a grinding water drain pipe 150 connected with the vacuum filtering tub 40 of the waste water filtering apparatus lb so that the grinding water is discharged during the grinding of the spectacles lens. The spectacles lens filtering apparatus 200 of the present invention having the above construction basically employs the waste- water filtering apparatus lb of the present invention as shown in FIGS. 2 and 3, which includes the valve means 80 installed in the clean- water storing tub 110 of the apparatus lb, the air drawing means 100, and a controller 230 that is connected electrically with the driving motors respectively installed on the pumps 130 and operates the waste- water filtering apparatus lb at a certain period in response to the grinding of the lens.

The operation of the spectacles lens grinding water filtering apparatus 200 of the present invention is described with reference to FIG. 9. As a user pushes a start switch for beginning the operation of the grinding device 220, the controller 230 operates the inner motor of the pump 130 and simultaneously operates the motor 108a of the air drawing means 100 and the motor 88 of the valve means 80.

In such a situation, the clean water in the clean- water storing tub 110 is supplied to the spectacles lens grinding device 220 located over the accommodating means 210 through the supply pipe 140 via the pump 130, whereby the spectacles lens is grinded by the grinding roll 220a of the grinding device 220. Such a grinding device 220 has been known publicly, which grinds one spectacles lens while it is operating for one minute and fifty seconds, and in such a situation, the amount of the supplied clean water is about 7.7 liters.

Accordingly, as one spectacles lens is grinded^' for one minute and fifty seconds by the grinding device 220, more than 7.5 liters of grinding water including a great amount of grinding powder, heavy metallic component, and floating substances are is generated. The grinding water including such grinding powder is filled up on the filtering member 70 of the vacuum filtering tub 50 through the inflow port 10 of the vacuum filtering tub 50 of the waste-water filtering apparatus lb of the present invention through the drain pipe 150 connected with the grinding device 220. In such a situation, the size of the vacuum filtering tub 50 is such that the diameter is about 10cm and the height is about 17cm for example, however, the size is not restricted to the example.

Next, one closing member 90a of the rotating member 90 closes the dirt inflow port 86a as the motor 88 of the valve means 80 is operated by the controller 230. The air at the inside of the lower casing 52 is drawn through the air drawing port 86b of the casing 86 of the valve means 80, the air drawing port 86c and the connection pipe 104 toward the lower area of the filtering member 70 of the vacuum filtering tub 50 until it reach the air drawing fan 108, by the drawing fan 108 driven by the motor 108a.

Simultaneously, the inside of the lower casing 52 is vacuumized at an instance as the cover 32 of the lower casing 52 of the vacuum filtering tub 50 is pulled upward by force. Then the fiber filter 60 is formed with ultra-fine pores of 0.01 m-0.12 m as the drawing pressure of greater than 25mmAp, preferably 25-50mmAq, is applied. Only the liquid state pure water passes through the filtering member 70 including the fiber filter 60 since the dirt such as the solid state grinding powder, heavy metal component, and float substances having the size greater than the ultra-fine pores are filtered by the filtering member 70. The filtered clean water opens the cover 32 of the lower discharge port 30 and is dropped and stored into the clean- water storing tub 110.

Accordingly, the clean water is recycled and circulated to the spectacles lens grinding device 220 when the pump 130 operates, whereby the grinding of the spectacles lens is continuously performed.

In such a situation, the clean water filtered by the fiber filter 60 flows to the cover 32 while the air is drawn through the air drawing port 40, and flows through the gap between the cover 32 and the clean-water discharge port 30 of the lower casing 52 of the vacuum filtering tub continuously to close the gap to maintain the vacuum state. And, as the drawing of air is finished, the inner pressure vanishes, and the filtered water is dropped through the clean-water discharge port 30 so as to flow into the clean-water storing tub 110. Next, the controller 230 shown in FIG. 9 drives the motor 108a of he air drawing means 100 and the driving motor in the valve means 80, that is, the stepping motor, in five seconds by counting the time with a timer (not shown) equipped in the controller 230. Then, the rotating member 90 of the valve means 80 is rotated so that the other closing member 90b closes the air drawing port 86b and opens the dirt inflow port 86a at the opposite side, and the controller 230 drives the motor 108a of the air drawing means 100 for ten seconds.

Accordingly, the dirt such as the grinding powder remaining on the filtering member 70 of the vacuum filtering tub 50 passes through the dirt inflow port 86a of the valve means 80, the air drawing port 86c, the connection pipe 104, and the drawing fan 108 of the air drawing means by the air drawing force generated in such a situation, and then is collected in the dirt collecting tub 120 through the drain pipe 102 connected with the drawing fan 108.

In other words, the spectacles lens grinding water filtering step is as follows. The controller 230 drives the pump 130, the driving motor 108a of the air and dirt drawing means 100, and the stepping motor 88 of the valve means 80. The dirt inflow port 86a is closed by the rotating member 90, and the air drawing port 86b is opened, by which the lower area of the fiber filter 60 is vacuumized. The clean water that has passed through the fiber filter 60 is dropped and stored into the storing tub 110 for one minute and fifty seconds. The operation is stopped for five seconds, and after five seconds, the controller

230 operates the drawing means 100 and the valve means 80 again to close the air drawing port 86b and open the dirt inflow port 86a, whereby the dirt is collected in the collecting tub 120 for ten minutes and then the spectacles lens filtering process is completed.

Next, the controller 230 stops operating the motor of the air drawing fan 100, and the user loads a new spectacles lens on the grinding device 220. As the pump 130 is driven by the controller 230 again, the clean water is supplied again to perform a new grinding operation of the spectacles lens, and the grinding water generated in such a situation is filtered again.

Therefore, according to the spectacles lens grinding water filtering apparatus 200 of the present invention, a superior filtering function with respect to the grinding water is provided. Thus, in comparison with the spectacles lens grinding water filtering process with the conventional filter, there are provided the effects that the cleanness degree of the filtered clean water is superior and the water pollution caused by the sewage containing the grinding water is prevented. The following table 1. shows the result of filtering the spectacles lens grinding water with the spectacles lens grinding water filtering apparatus 200 having the waste-water filtering apparatus of the present invention, in which 1.5 liter of the grinding water achieved after grinding one spectacles lens with 7.5 liters of water for one minute and fifty seconds is compared with clean water filtered by passing through the filtering member 70 including the fiber filter 60 of the vacuum filtering tub 50. This testing has been performed by Korea

Testing and Research Institute for Chemical Industry (Receipt No. TAS-019973, August. 30, 2002).

[Table 1. Testing result of the spectacles lens grinding water and the filtered water thereof]

According to table 1, 7.5 liters of grinding water is generated when one spectacles lens is grinded in a spectacles store, however, if the grinding water is filtered by the spectacles lens grinding water filtering apparatus 200 using the waste-water filtering apparatus lb of the present invention, the floating substances and hazardous copper and lead components are filtered perfectly, the water quality is improved from acid water to alkaline water, and the turbidity of water is remarkably improved below the standard amount of city water, which shows the superior filtering efficiency.

Furthermore, as shown in table 1, the chromaticity according to the floating substances and turbidity are improved. Thus, if the waste water of the livestock industry that is generated by the biological process on the waste water and has been wasted excessively is firstly filtered by the waste- water filtering apparatus lb of the present invention, the floating material can be filtered perfectly and the turbidity can be improved.

Consequently, according to the spectacles lens filtering apparatus 200 using the waste-water filtering apparatus lb of the present invention, the grinding water is filtered immediately to be used as a clean water and the dirt such as the grinding water is separately collected, so the water pollution caused by the spectacles lens grinding water is prevented perfectly and the collected grinding powder can be reused easily.

Meanwhile, the news program on SBS TV in Korea has broadcasted the news that the water is polluted by the sewage without filtering the grinding water generated by the grinding of the spectacles lens, including the heavy metal such as lead. The applicant of the present invention has developed the waste-water filtering device la, the waste-water filtering apparatus lb, and the spectacles lens grinding water filtering apparatus 200 employing the same that can prevent the water pollution caused by the spectacles lens grinding water effectively.

INDUSTRIAL APPLICABILITY According to the waste-water filter and the waste-water filtering apparatus and method using the same, since the filtering member including the fiber filter is installed in the vacuum filtering tub and the drawing pressure is applied to the fiber filter, the waste water such as the grinding water can be filtered perfectly.

Moreover, since the filtering apparatus has a simple construction and provides superior filtering efficiency, it is easy to manufacture and use the apparatus. In particular, the water pollution and environmental pollution caused by the waste water can be prevented in advance since it provides high filtering efficiency with respect to the waste water.

Finally, according to the spectacles lens filtering apparatus of the present invention, most of the grinding water generated by the grinding of the spectacles lens can be filtered easily with the waste-water filtering apparatus, and the filtered clean water can be circulated to be reused in grinding the spectacles lens. Therefore, the water pollution by the grinding water can be prevented and the collected spectacles lens grinding powder can be recycled.

The preferred embodiments have been illustrated and described so far, however, it will be understood by those skilled in the art that various changes and modifications can be made within the spirit and the scope of the present invention, and accordingly, the scope of the present mvention is not limited within the described range but the following claims and the equivalents thereof.

Claims

WHAT IS CLAIMED IS:

1. A waste-water filtering device comprising: a fiber filter 60; and a vacuum filtering tub 50 that is imbedded with the fiber filter 60 and into which waste water flows, the vacuum filtering tub 50 for discharging filtered clean water and filtered dirt separately; wherein only liquid state water passes through ultra-fine pores formed on the filter fiber 60 while an inside of the vacuum filtering tub 50 is maintained to a vacuum state with a drawing pressure applied to the filter fiber 60 so as to filter the waste water.

2. The waste- water filtering device of claim 1, wherein a filtering member 70 including the fiber filter 60 is disposed in the vacuum filtering tub 50.

3. The waste-water filtering device of claim 2, wherein the filtering member 70 comprises a screen net 72, a space mat filter 74, and the fiber filter 60 that are piled up in a casing 76 attached in the vacuum filtering tub 50.

4. The waste-water filtering device of claim 1, wherein the fiber filter 60 is comprised of a multilayer fiber filter in which a HAPA medium 62, a lypore medium 64, and a polyester foam 66 are piled up.

5. The waste-water filtering device of claim 1, wherein the fiber filter 60 is so constructed that solid-state dirt is filtered through ultra- fine pores of 0.01-0.12 m formed by the drawing pressure caused by the inner vacuum state formed while air at a lower area of the fiber filter 60 is being drawn, and only pure water of liquid state passes through the ultra-fine pores to filter the waste water.

6. The waste-water filtering device of claim 1, wherein the vacuum filtering tub 50 has: an inflow port 10 through which the waste water flows in; a discharge port 20 for discharging the dirt filtered by the fiber filter 60 toward an outside; a clean-water discharge port 30 with a covering member 32 closed at the inner vacuum state, the clean water discharging port 30 for discharging pure water filtered by the fiber filter 60; and an air drawing port 40 for drawing air in the vacuum filtering tub 50 so as to apply the drawing pressure onto the fiber filter 60 while the inside of the vacuum filtering tub 50 is maintained to the vacuum state.

7. A waste-water filtering apparatus with a waste-water filtering device, the apparatus comprising: a vacuum filtering tub 50 having a waste-water inflow port 10, a dirt discharge port 20, a clean-water discharge port 30 that is covered by a covering member 32 at a vacuum state of inside and discharges filtered pure water, and an air drawing port 40 used for vacuumizing the inside; a fiber filter 60 disposed in the vacuum filtering tub 50 between the dirt discharge port 20 and the air drawing port 40, the fiber filter 60 by which only liquid state water passes through ultra-fine pores formed by drawing pressure while an inner vacuum state of the vacuum filtering tub 50 is maintained; a valve means 80 connected with the dirt discharging port 20 and the air drawing port 40 of the vacuum filtering tub 50, the valve means 80 being used for drawing air and discharging filtered dirt outside the vacuum filtering tub 50; and an air/dirt drawing means 100 connected to the valve means 80, the air/dirt drawing means 100 being used for vacuumizing the inside of the vacuum filtering tub 50 by drawing air out of the vacuum filtering tub 50 and for discharging the filtered dirt.

8. The waste- water filtering apparatus of claim 7, wherein a filtering member 70 including the fiber filter 60 is disposed in the vacuum filtering tub 50.

9. T e waste-water filtering apparatus of claim 8, wherein the filtering member

70 comprises a screen net 72, a space mat filter 74, and the fiber filter 60 that are piled up in a casing 76 attached in the vacuum filtering tub 50.

10. The waste- water filtering apparatus of claim 7, wherein the fiber filter 60 is comprised of a multilayer fiber filter in which a HAPA medium 62, a lypore medium 64, and a polyester foam 66 axe piled up.

11. The waste-water filtering apparatus of claim 7, wherein the fiber filter 60 is so constructed that solid-state dirt is filtered through ultra-fine pores of 0.01-0.12 m formed by the drawing pressure caused by the inner vacuum state formed while air at a lower area of the fiber filter 60 is being drawn, and only pure water of liquid state passes through the ultra-fme pores to filter the waste water.

12. The waste-water filtering apparatus of claim 7, wherein a dirt discharge pipe 82 and an air drawing pipe 84 that are separately connected with the valve means 80 are respectively connected to the dirt discharge port 20 and the air drawing port 40 of the vacuum filtering tub 50, and a drain pipe 102 for draining dirt discharged from the vacuum filtering tub 50 is connected with the air/dirt drawing means 100.

13. The waste-water filtering apparatus of claim 7, wherein the vacuum filtering tub 50, the valve means 80 and the air/dirt drawing means 100 are disposed on a clean- water storing tub 110 that is disposed under the vacuum filtering tub 50 and to which the clean-water discharge port 30 of the vacuum filtering tub 50 is connected therein; a dirt collecting tub 120 connected with the drain pipe 102 is prepared on a side of the clean- ater storing tub 110, and a pump 130 for supplying clean water from an outside is provided on the clean- water storing tub 110.

14. The waste-water filtering apparatus of claim 7, wherein the valve means 80 comprises: a casing 86 that are integrally formed with dirt/air inflow ports 86a and 86b respectively connected with the dirt discharge pipe 82 and the air drawing pipe 84, and air drawing port 86c connected with a connection pipe 104 of the air drawing means 100; a rotating member 90 so installed in the casing 86 as to be rotated by a motor 88, the rotating member 90 having closing members 90a and 90b for opening/closing the inflow ports 86a and 86b by turns; and a lid 92 fixed on the casing 86 so as to close and seal the casing 86.

15. The waste-water filtering apparatus of claim 7, wherein the air/dirt drawing means 100 comprises: a casing 106 respectively connected with the drain pipe 102 and the connection pipe 104 connected with the valve means 80; and an air drawing fan 108 installed in the casing 106 and rotated by a motor 108a installed in the casing 106.

16. The waste-water filtering apparatus of claim 7, wherein the vacuum filtering tub 50 comprises: a lower casing 52 formed with the clean-water discharge port 30 on a lower part thereof, and fixed through a clean-water inflow port 112 of the clean- water storing tub 110; and an upper casing 54 fixed on a casing 76 of the filtering member 70 and formed integrally with the waste-water inflow port 10 and the dirt discharge port 20, wherein the upper casing 54 further comprises an upper screen net 56.

17. The waste-water filtering apparatus of claim 9 or claim 16, wherein the casing 76 of the filtering member 70 comprises upper and lower casings 76a and 76b respectively imbedded with more than one layer of a screen net 72, a space mat filter 74, and the fiber filter 60 of the filtering member 70 consecutively piled up therein, the upper and lower casings 76a and 76b being attached to and detached from each other, wherein the upper and lower casings 54 and 52 are respectively assembled with the upper and lower casings 76, and the upper and lower casings 76a and 76b are formed with apertures 78a and 78b.

18. A method for filtering waste water with the waste-water filtering apparatus as depicted in claim 7, the method comprising: a valve operating step for closing a dirt discharge port 20 of a vacuum filtering tub 50 and opening an air drawing port 40 of the vacuum filtering tub 50 by operating a valve means 80; a waste-water inflow step that the waste-water flows through the waste-water inflow port 10 of the vacuum filtering tub 50 onto a filtering member 70 in the vacuum filtering tub 50, the filtering member 70 including a fiber filter 60; a waste-water filtering step for filtering the waste water so that solid state dirt in the waste water is filtered and liquid state pure water is passed through ultra-fine pores formed on a the fiber filter 60 by a drawing pressure applied to the fiber filter 60 while a lower part of the fiber filter 60 of the filtering member 70 in the vacuum filtering tub 50 is vacuumized as an air/dirt drawing means 100 connected with an air drawing port 40 of the vacuum filtering tub 50 via the valve means 80 operates; and a clean- water and dirt collecting step that the filtered clean water is discharged through the lower discharge port 30 of the vacuum filtering tub 50 and the dirt filtered by the filtering member 70 is collected in a collecting tub 120 via the dirt drawing means 100 through the discharge port 20 as the valve means 80 is operated.

19. The method for filtering waste- water of claim 18, wherein the fiber filter 60 is comprised of a multilayer fiber filter in which a HAPA medium 62, a lypore medium 64, and a polyester foam 66 are piled up; and the fiber filter 60 is so constructed that solid-state dirt is filtered through ultra-fine pores of 0.01-0.12 m formed by the drawing pressure caused by the inner vacuum state formed while air at a lower area of the fiber filter 60 is being drawn, and only pure water of liquid state passes through the ultra-fine pores to filter the waste water.

20. An apparatus for filtering spectacles lens grinding water comprising: a waste-water filtering apparatus lb as depicted in claim 7; a means 210 for accommodating the waste-water filtering apparatus; and a spectacles lens grinding device 220 disposed over the accommodating means 210, and having a clean- water supply pipe 140 so connected with a clean-water storing tub 110 of the waste water filtering apparatus lb as to supply clean water while a spectacles lens is being grinded, and a grinding water drain pipe 150 so connected with the vacuum filtering tub 50 of the waste-water filtering apparatus lb as to drain the grinding water generated while the spectacles lens is being grinded, whereby water pollution caused by the grinding water is prevented.

21. The apparatus for filtering spectacles lens grinding water of claim 20, further comprising a controller 230 disposed on the clean-water storing tub 110 of the waste-water filtering apparatus lb and is connected electrically with driving motors respectively installed on a valve means 80, an air drawing means 100, and a pump 130 in the waste- water filtering apparatus lb, the controller 230 for operating the waste-water filtering apparatus lb in response to a grinding operation of spectacles lens performed by the grinding apparatus 220.