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Patent roundup
Patents
Filtration+Separation April 2005
Patent roundup M
arten Terpstra outlines some interesting patent applications that have emerged this month, including a novel way of using DNA – acting as a tobacco filter...
Steve Benesi, a filter apparatus designer based in California, USA, has developed a new slurry filtering system (see figure 1). The filter apparatus (32) includes a slurry input port (34); an upper plate (36) with an internal cavity; a lower plate (38) with an internal cavity that together forms a filter chamber (40) through connection of the plates and their internal cavities; and filter media (42) between the upper and lower plates.
T P
Wash fluids, gases passing through the slurry, and liquids separated from the slurry as filtrate, all pass through the surface and exit through the filtrate exit port attached to the
To &from fig
iLq uid clearing or cak e forming gas
(International Patent Application WO 2005/007270.)
0 5 a Wsh fluids 2 5
team S
Drying or conditioning gas
Mark Lyles from Illinois, USA, has created a filter for removing carcinogens from a gas or a liquid. The filter contains nucleic acids, for example DNA or apurinic acid, with which carcinogens may react. In specific embodiments the filters are used for tobacco or industrial pollutants.
9 4 late(s) P movement apparatus 2 3
4 5
The filter media is a porous filter belt – stationary and supported on a suitable surface (43) when the plates are closed, and able to travel through the chamber when the plates are separated. The filter media collects the solids of the prepared input slurry (44) when the filter is operated with the plates closed, and carries the collected filter cake out of the chamber when the plates are separated.
lower plate, which carries the liquids separated from the slurry to selected locations.
6 1 ontroller C
6 4
0 1 7 5
6 5 eVnt
2 3
s( lurry 3 ) from fig 1
8 5
4 3 6 3
0 4
2 4
8 4 3 4
4
Figure 1 – WO 2005/007270.)
8 3
Lyles has discovered that DNA may serve as a good filter or filter coating for the removal of polyaromatic hydrocarbons from tobacco smoke. In its current form, the filter may be of a size and shape that permits its use as a tobacco smoke filter. When used as a cigarette filter, the nucleic acid is generally DNA. The size of this cigarette filter is about 19 to 25 mm in length and about 7.8 mm in diameter. The amount of DNA in the filter is an amount provided by applying about 0.3 ml of an aqueous saturated DNA solution onto the filtering material of the cigarette filter. The aqueous solution is
37
38
Patents
Filtration+Separation April 2005
liquid, super-buoyant media produce a highlyadvantageous means of naturally and gravimetrically separating both clean and contaminated filter media, and process liquid, into separate ‘phases’.
7
40a 45 56wu 28
23
25
46
24
To regenerate the filter media, the housing is drained and a nozzle creates a backwash spray that washes the particulate material from the filter media. During the backwash process, the filter media rises past the nozzle as the level of the backwash liquid in the housing rises, so that the entire filter media is regenerated.
41 56ru 28 50
h
4
40
43
Under normal filtering operation, the filter media is contained within a filter housing by a bed support near the top of the filter housing, and particulate material is filtered from a process liquid that passes through the housing.
5
49b 49 49a 62 3
40 42 27
58w
62a 22
58r
Figure 3 shows a schematic representation of the respective apparatus, showing the superbuoyant filter particles (14), and the washing nozzle (44).
61 51r
56w
51w
56r
6
13
56wb 56rb
12 57
H 26
(US Patent Application 2005/0029204.) 63
61
Yi-Lang Ku of the Taiwan Semiconductor Manufacturing Co Ltd in Miao-Li-Hsien, has designed a Y strainer which has an automatic flushing capacity (see figure 4).
21 2
In the fabrication process for semiconductor devices, numerous fabrication steps must be executed on a silicon wafer in order to complete integrated circuits on the wafer.
Figure 2 – European Patent Application 1 508 618
preferably applied by injection into the approximate midpoint of the filter. The amount of DNA distributed on the filtering material is about 5-7 mg.
Since the processing of silicon wafers requires extreme cleanliness in the processing environment in order to minimise the presence of contaminating particles or films, the surface of the silicon wafer is frequently
majority of the medium to float on top of the process liquid. Due to the significant differences in specific gravity between the media and the process
Lyles suggests that, as well as being used in the removal of carcinogens in tobacco, other systems such as exhaust gas purifiers can have DNA as a filtering agent.
26
27 S
(US Patent Application 2005/016555.)
31 28
Yoshihiro Seto and others, all working for the Fuji Photo Film Co Ltd based in Kanagawaken, Japan, have designed a device which can extract nucleic acid from a sample liquid, preventing problems with contamination.
23 110 111
V
32 V
38
109
33
22
17
V
16
108 21
34 S
14 43
41
36
The device, shown in figure 2, extracts a nucleic acid from a sample liquid using an extracting filter cartridge. The cartridge comprises a tubular main body having an opening at its top end, as well as a filter member, which is held within, and at the base of, the tubular main body.
42
P 29
S
V
37
107 18
44 S
13 19 105
39 104
106 12
3
(European Patent Application 1 508 618.) Steven Schwartzkopf, a US, Californian filter specialist has overcome the disadvantages encountered with prior bed filtration systems, by developing a filter incorporating a super-buoyant filter medium with specific gravity substantially lower than that of the process liquid being filtered. This enables the
112
24
8 6
V P
2
7
Figure 3 – US Patent Application 2005/0029204
47
11
4 9 103 101
46 102
V 48
54
Patents
Filtration+Separation April 2005
53
54
69
55
52
51
53
97 62
15 57
63
58 68
67
Figure 4 – US Patent Application 2005/0023196
cleaned after each processing step. For example, the surface is cleaned after the deposition of a surface coating layer such as oxide, or after the formation of a circuit, by a processing step such as etching. The filter-flushing operation can be monitored during the continuous operation of a water cooling system. An intake pressure monitor and an outlet pressure monitor can be provided on the intake and outlet sides (respectively) of the Ystrainer to monitor the pressure of water flowing through the water drain line and water return line, and indicate the need to clean or replace the filter (58) when the water pressure measured by the intake pressure monitor exceeds that measured by the outlet pressure monitor by a predetermined value – typically about 5 psi. A power supply and a controller may be connected to the drain valve (62) of the Ystrainer (51), the intake pressure monitor and the outlet pressure monitor, to automatically flush the filter when the water pressure measured by the intake pressure monitor exceeds the water pressure measured by the outlet pressure monitor. (US Patent Application 2005/0023196.)
About the author Marten Terpstra is a technological and scientific publicist and literature researcher, specialising in patent literature. He has written or co-written a large number of books on subjects such as wastewater purification by means of flocculants or by biological processes, immunoassay, exhaust gas purifying, and new materials. He has made several literature searches for clients all over the world, to determine the validity of existing patents or patent applications.
39
Filtration+Separation April 2005
Patent roundup M
arten Terpstra outlines some interesting patent applications that have emerged this month, including a novel way of using DNA – acting as a tobacco filter...
Steve Benesi, a filter apparatus designer based in California, USA, has developed a new slurry filtering system (see figure 1). The filter apparatus (32) includes a slurry input port (34); an upper plate (36) with an internal cavity; a lower plate (38) with an internal cavity that together forms a filter chamber (40) through connection of the plates and their internal cavities; and filter media (42) between the upper and lower plates.
T P
Wash fluids, gases passing through the slurry, and liquids separated from the slurry as filtrate, all pass through the surface and exit through the filtrate exit port attached to the
To &from fig
iLq uid clearing or cak e forming gas
(International Patent Application WO 2005/007270.)
0 5 a Wsh fluids 2 5
team S
Drying or conditioning gas
Mark Lyles from Illinois, USA, has created a filter for removing carcinogens from a gas or a liquid. The filter contains nucleic acids, for example DNA or apurinic acid, with which carcinogens may react. In specific embodiments the filters are used for tobacco or industrial pollutants.
9 4 late(s) P movement apparatus 2 3
4 5
The filter media is a porous filter belt – stationary and supported on a suitable surface (43) when the plates are closed, and able to travel through the chamber when the plates are separated. The filter media collects the solids of the prepared input slurry (44) when the filter is operated with the plates closed, and carries the collected filter cake out of the chamber when the plates are separated.
lower plate, which carries the liquids separated from the slurry to selected locations.
6 1 ontroller C
6 4
0 1 7 5
6 5 eVnt
2 3
s( lurry 3 ) from fig 1
8 5
4 3 6 3
0 4
2 4
8 4 3 4
4
Figure 1 – WO 2005/007270.)
8 3
Lyles has discovered that DNA may serve as a good filter or filter coating for the removal of polyaromatic hydrocarbons from tobacco smoke. In its current form, the filter may be of a size and shape that permits its use as a tobacco smoke filter. When used as a cigarette filter, the nucleic acid is generally DNA. The size of this cigarette filter is about 19 to 25 mm in length and about 7.8 mm in diameter. The amount of DNA in the filter is an amount provided by applying about 0.3 ml of an aqueous saturated DNA solution onto the filtering material of the cigarette filter. The aqueous solution is
37
38
Patents
Filtration+Separation April 2005
liquid, super-buoyant media produce a highlyadvantageous means of naturally and gravimetrically separating both clean and contaminated filter media, and process liquid, into separate ‘phases’.
7
40a 45 56wu 28
23
25
46
24
To regenerate the filter media, the housing is drained and a nozzle creates a backwash spray that washes the particulate material from the filter media. During the backwash process, the filter media rises past the nozzle as the level of the backwash liquid in the housing rises, so that the entire filter media is regenerated.
41 56ru 28 50
h
4
40
43
Under normal filtering operation, the filter media is contained within a filter housing by a bed support near the top of the filter housing, and particulate material is filtered from a process liquid that passes through the housing.
5
49b 49 49a 62 3
40 42 27
58w
62a 22
58r
Figure 3 shows a schematic representation of the respective apparatus, showing the superbuoyant filter particles (14), and the washing nozzle (44).
61 51r
56w
51w
56r
6
13
56wb 56rb
12 57
H 26
(US Patent Application 2005/0029204.) 63
61
Yi-Lang Ku of the Taiwan Semiconductor Manufacturing Co Ltd in Miao-Li-Hsien, has designed a Y strainer which has an automatic flushing capacity (see figure 4).
21 2
In the fabrication process for semiconductor devices, numerous fabrication steps must be executed on a silicon wafer in order to complete integrated circuits on the wafer.
Figure 2 – European Patent Application 1 508 618
preferably applied by injection into the approximate midpoint of the filter. The amount of DNA distributed on the filtering material is about 5-7 mg.
Since the processing of silicon wafers requires extreme cleanliness in the processing environment in order to minimise the presence of contaminating particles or films, the surface of the silicon wafer is frequently
majority of the medium to float on top of the process liquid. Due to the significant differences in specific gravity between the media and the process
Lyles suggests that, as well as being used in the removal of carcinogens in tobacco, other systems such as exhaust gas purifiers can have DNA as a filtering agent.
26
27 S
(US Patent Application 2005/016555.)
31 28
Yoshihiro Seto and others, all working for the Fuji Photo Film Co Ltd based in Kanagawaken, Japan, have designed a device which can extract nucleic acid from a sample liquid, preventing problems with contamination.
23 110 111
V
32 V
38
109
33
22
17
V
16
108 21
34 S
14 43
41
36
The device, shown in figure 2, extracts a nucleic acid from a sample liquid using an extracting filter cartridge. The cartridge comprises a tubular main body having an opening at its top end, as well as a filter member, which is held within, and at the base of, the tubular main body.
42
P 29
S
V
37
107 18
44 S
13 19 105
39 104
106 12
3
(European Patent Application 1 508 618.) Steven Schwartzkopf, a US, Californian filter specialist has overcome the disadvantages encountered with prior bed filtration systems, by developing a filter incorporating a super-buoyant filter medium with specific gravity substantially lower than that of the process liquid being filtered. This enables the
112
24
8 6
V P
2
7
Figure 3 – US Patent Application 2005/0029204
47
11
4 9 103 101
46 102
V 48
54
Patents
Filtration+Separation April 2005
53
54
69
55
52
51
53
97 62
15 57
63
58 68
67
Figure 4 – US Patent Application 2005/0023196
cleaned after each processing step. For example, the surface is cleaned after the deposition of a surface coating layer such as oxide, or after the formation of a circuit, by a processing step such as etching. The filter-flushing operation can be monitored during the continuous operation of a water cooling system. An intake pressure monitor and an outlet pressure monitor can be provided on the intake and outlet sides (respectively) of the Ystrainer to monitor the pressure of water flowing through the water drain line and water return line, and indicate the need to clean or replace the filter (58) when the water pressure measured by the intake pressure monitor exceeds that measured by the outlet pressure monitor by a predetermined value – typically about 5 psi. A power supply and a controller may be connected to the drain valve (62) of the Ystrainer (51), the intake pressure monitor and the outlet pressure monitor, to automatically flush the filter when the water pressure measured by the intake pressure monitor exceeds the water pressure measured by the outlet pressure monitor. (US Patent Application 2005/0023196.)
About the author Marten Terpstra is a technological and scientific publicist and literature researcher, specialising in patent literature. He has written or co-written a large number of books on subjects such as wastewater purification by means of flocculants or by biological processes, immunoassay, exhaust gas purifying, and new materials. He has made several literature searches for clients all over the world, to determine the validity of existing patents or patent applications.
39