Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D47/00—Separating dispersed particles from gases, air or vapours by liquid as separating agent
  • B01D47/16—Apparatus having rotary means, other than rotatable nozzles, for atomising the cleaning liquid
  • B01D47/18—Apparatus having rotary means, other than rotatable nozzles, for atomising the cleaning liquid with horizontally-arranged shafts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D47/00—Separating dispersed particles from gases, air or vapours by liquid as separating agent
  • B01D47/02—Separating dispersed particles from gases, air or vapours by liquid as separating agent by passing the gas or air or vapour over or through a liquid bath
  • B01D47/028—Separating dispersed particles from gases, air or vapours by liquid as separating agent by passing the gas or air or vapour over or through a liquid bath by directing the gas through a wetted wire mesh or a perforated plate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
  • B01D53/34—Chemical or biological purification of waste gases
  • B01D53/46—Removing components of defined structure
  • B01D53/68—Halogens or halogen compounds

Definitions

• the present invention relates to a novel waste gas scrubbing apparatus.
• the semi-conductor manufacturing process requires the deposition of a layer of silicon on a silicon wafer.
• the photographic tracing process involves etching away the silicon from around the traced lines. Layers of conductive materials are then layered atop etched areas. Waste gases such as ⁇ ilane, trichlorosilane, tetraethyl orthosilicate, phosphine and the like are produced in such electronics fabrication process and must be safely disposed.
• Toxic gases such as silanes
• Toxic gases such as silanes
• Toxic gases also include particulate matter which form viscid substances tending clog scrubbing machinery used in the prior art.
• toxic gases from the chip making manufacturing plants were diluted with water and transported to a sprinkler treatment plant.
• the sprinklers employed in this scrubbing system were ineffective in capturing a high percentage of the gases.
• mechanical portions of the prior system were easily clogged and rendered, inoperable by the. viscid substances resulting from the solid and gas admixtures heretofore described. Since failure to quickly remove noxious gases from the chip making process extends to spoil the newly manufactured chips, breakdown of a scrubbing system severely interrupts the manufacturing process. Needless to say the prior systems required extensive maintenance and consequential exposure of maintenance personnel to toxic fumes.
• the scrubber of the present invention employs an enclosure forming a chamber therewithin.
• the chamber contains a body of liquid which is used in the scrubbing process.
• the chamber includes a liquid portion and a gas portion thereabove. Consequently, a liquid inlet and outlet connects to the chamber such that the liquid is constantly circulated through the chamber.
• a gas outlet leads from the chamber and extends to the exterior of the chamber or to a recirculation apparatus which feeds a portion of the scrubbed exhaust gas back into the chamber.
• the present invention also includes a rotatable member such as a turbine which turns within the chamber.
• the rotatable member includes means for creating turbulent fluid flow at the periphery of the rotatable member.
• a series of vanes or blades may be formed at the periphery of the turbine to produce this effect.
• Waste gas may be fed into the turbine within the chamber along the axis of the same and pass outwardly through openings to the periphery of the turbine, such that gas where turbulent flow is created by the vanes.
• a turbine motor or driving means may extend into the chamber by the way of a drive shaft.
• the invention may include means for mechanically turning the drive shaft at the outside of the chamber should the drive shaft become clogged due to residual solid material.
• a stator at least partially surrounds the rotatable member within the chamber and forms a channel therebetween.
• the channel includes a first opening which communicates with the body of water and permits liquid to pass into contact with the rotatable member periphery for the purpose of atomization.
• the channel then extends about the periphery of the rotatable member and exits a second opening which generally points or directs the fluid flow back toward the body of liquid.
• gases flowing from the central axial region of the turbine and liquid from the liquid body mix in a turbulent fashion within the channel.
• the turbine may be positioned within the chamber to extend directly into a portion of the liquid body.
• the scrubber of the present invention also includes means for delivering waste gas into the rotatable member which may take the form of a fan which is positioned adjacent the rotatable member within the chamber.
• the fan may be positioned on the drive shaft which also turns the turbine and is, thus, coaxial with the turbine. • The fan prevents liquid from passing from the vicinity of the channel between the stator turbine to the waste gas inlet, which prevents clogging of such inlet.
• Another object of the present invention is to provide a waste gas scrubber which greatly lessens the chance of explosions from the handling of waste gases such as hydrogen.
• a further object of the present invention is to provide a waste gas scrubber which is simple to install and economical to maintain within confined spaces.
• Another object of the present invention is to provide a waste gas scrubber which is not susceptible to being plugged up by solid materials which normally accompany waste gases in certain processes.
• a further object of the present invention is to provide a waster gas scrubber which is capable of operating at a constant inlet pressure and at variable inlet volumes.
• FIG. 1 is a vertical sectional view of the waste gas scrubber of the present invention.
• FIG. 2 is a horizontal sectional view taken along line 2-2 of Fig. 1.
• FIG. 3 is a sectional view taken along line 3-
• FIG. 4 is a sectional view taken along line 4-
• FIG. 5 is a sectional view taken alone line 5-
• FIG. 6 is a sectional view taken along line 6-
• the waste gas scrubber 10 includes as one of its elements a housing 12 which is shown as a metallic member having an inner wall 14 and an outer wall 16. Housing 12 is constructed to be inpervious to the passage of waste gases being treated therewithin. Plate 18 is held to inner wall 14 by fasteners 20. Passage 22 permits the replacement and removal of certain mechanisms within housing 12, which will be described hereinafter. In addition, plate 24 is held to inner wall 14 by fasteners 26. An opening 26 serves the same purpose as opening 22 in the assemblage and maintenance of scrubber 10. It should be noted that although housing 12 is depicted as being metallic, other materials may be employed in this regard such as plastics, which may be visually transparent. Chamber 28 is formed by housing 12.
• Waste gas inlet 30, Fig. 1 connects to a waste gas generating apparatus (not shown) .
• waste gases entering inlet 30 may take the form of phosphine, germanium tetrachloride, hexafluoroethane, silane, tetraethyl orthosilicate and the like, generally exuding from processes in the electronic industries.
• a potential explosive free hydrogen may be passed into waste gas inlet 30 as a result of the same electronics industry processes.
• Port 32 permits injection of the inert gas into chamber 28 to obviate the possibility of outside air entering chamber 28 of scrubber 10 and causing an explosion.
• Waste gas entering inlet 30 is directed 90 degrees and is fed into a fan 34, best shown on Figs. 1 and 6.
• Fan 34 is keyed to shaft 36 which is rotated by motor 38 within chamber 28.
• Motor 38 receives electrical current through conductors 40 which extend through housing 28 in air-tight fashion by the use of seal 42.
• Coupling 44 connects the output shaft 46 of motor 38 to shaft 36 with chamber 28.
• Bearings 48 and 50 are enclosed by caps 52 and 54 which surround shaft 36.
• Cap 52 is fastened to an end plate 56 by the use of fasteners 64.
• End plate 56 further divides chamber 28 into a first portion 58 and a second portion 60.
• First portion 58 includes a provision of body of liquid 62, depicted in Figs. 3, 4, and 6.
• the body of liquid may be water or any other liquid which is employed in the scrubbing process.
• Scrubber 10 further includes as one as its elements, a rotatable member 66, clearly shown in Fig. 4.
• Rotatable member 66 possesses a plurality of vanes 68 at periphery 70 thereof.
• Vanes 68 are depicted in Fig. 4 as being triangular in cross-sectional configuration, however, vanes 68 may take any form consistant with periphery 70 of rotatable member 66 possessing a roughened surface.
• Plurality of vanes 68 are held in circular fashion by a pair of rings.72 and 74.
• Disc member 76 utilizes a hub 78 which keys to shaft 36 by the use of set screw..
• Ring 72 fits into a notch 82 of flange 84 located at the outer edge of fan 34.
• fan 34 and rotatable member 66 turn together on shaft 36, each being coaxial with shaft 36 in this regard.
• fan 34 includes a multiplicity of openings 86, Fig. 6, which permits gas to enter the interior portion 88 of rotatable member 66, yet prevents any liquid from liquid body 62 from passing back through inlet conduit 30. This aspect of the invention precludes the solidification of any waste gases ' within inlet conduit 30 prior to passing into the interior portion 88 of rotatable member 66.
• rotatable member 66 lies within a cylindrical stator 90 having a metallic outer shell 92 and a plurality of ridges 94 which extend inwardly from shell 92.
• Rotatable member 66 and stator 90 form a channel or gap 96 which is roughly annular in configuration.
• Stator 90 includes a first opening 98 which lies within liquid body 62.
• Baffle 100 surrounds another portion of rotatable member 96 and includes a second opening 102.
• Lip 104 serves as a stop for channel 96 creating a dead space 106.
• Means 114 is also provide in the present invention for circulating liquid into and out of the chamber first portion 58, Figs. 1, 3, and 4. Water is introduced into first portion 58 of chamber 28 through inlet 116. Stand pipe 118 serves as the outlet for liquid body 62 from chamber portion 58, Figs. 1 and 3. It should be noted that end plate 119 prevents liquid from liquid body 62 traveling through fan 34 and into rotatable member 66. Gas inlet 30 includes a flared portion 120, Fig. 3, which extends through plate 119 in order to feed waste gas directly into fan 34 and rotatable member 66.
• a gas outlet 122 is found in first portion 58 of chamber 28 located at a position higher and transversely from elbow 112 associated with opening 102 of channel 96.
• Gas outlet 122 extends through means 124 for generating pressure on chamber portion 58.
• Means 124 may be a turbin fan or blower which sucks scrubbed gas from chamber portion 58 and sends the same to gas outlet 126.
• Means 124 may take the form of a regenative blower Model No. DR083BC9Y, manufactured by EG. & G. Rotron, Industrial Division, Saugerties, N.Y., which also provides motor 38.
• gases such as oxygen, nitrogen, and some free hydrogen pass through gas outlet 126. It has been found that the free hydrogen readily quickly combines with oxygen to form water vapor, which is considered to be harmless.
• Scrubber 10 is further provided with means 128 for recirculating a portion of the scrubbed gas exiting outlet 122, Figs. 1, 2 and 5.
• Means 128 includes an offset conduit 130 which feeds into an air tight compartment 132.
• Flapper valve 134 includes a seat 136 which swings open and shut on pivot 138.
• Spring 140 attaches to seat 136 and a threaded screw 142 which adjust the tension on spring 140 and, thus, the ability of flapper valve seat 136 to open and shut.
• Seal 144 maintains the air tight integrity of chamber 128.
• pass conduit 146 feeds scrubbed gas from air tight compartment 132 which passes through plate 118 and directly into fan 34. Adjustment of threaded screw 142 maintains a relatively constant pressure at fan 34 with any changes in waste gas volume passing through inlet 30. It may be apparent that by pass conduit 144 passes through liquid body 62 prior to entry into chamber 28 first portion 58 via fan 34.
• Means 146 is also included in the present invention for mechanically turning shaft 36, Fig. 1.
• Means 148 takes the form of a knob 150 found on the end of shaft 36 within compartment 152. Coupler 154 fixes knob to shaft 36, in this regard. Thus, if any clogging prevents the temporary turning of shaft 36 or output shaft 46 of motor 38, knob 50 may be turned to loosen such clogging and initiate the normal operation of motor 38.
• waste gases are fed into inlet 30 with or without inert gases being injected through port 32. Importantly outside atmospheric does not enter the workings of scrubber 10 within compartment 28. Gases passing through inlet port 30 make a 90 degree turn and pass through the multiplicity of openings 86 of fan 34 and into the interior portion 88 of rotatable member 66. Fan 34 and rotatable member 66 turn on shaft 36 which is motivated by motor 38. Gases are then forced to the periphery 70 of rotatable member 66 and into channel 96 between periphery 70 of rotatable member 66 and stator 90, directional arrows 110. Fan 34 prevents moisture from passing from channel 96 back toward inlet 30 and by-pass conduit 144.
• Rotatable member 66 and fan 34 rotate at a very high rate.
• inlet gas is subjected to a very high turbulence at the periphery 70 of rotatable member 66 within channel 96.
• the plurality of vanes 68 on the periphery 70 of the rotatable member 66 and ridges 94 of stator 90 create such turbulence.
• rotatable member 66 lies in the vicinity of liquid body 62, which causes rotatable member 66 to move liquid into channel 96.
• the combination of turbulent gases and forced liquid creates a fine fog of atomized liquid, such as water, which scrubs the waste gases.
• the waste gases travel around rotatable member 66 and are directed by baffle 100 through outlet 102 of channel 96.
• Elbow 112 directs the gases back into liquid body 62.
• releasable gases such as oxygen, hydrogen, and nitrogen start to separate from the liquid body 62 and pass through air outlet 122.
• the scrubbed gases and solids within liquid body 62 are circulated by means 114 through liquid outlet 118 for disposal.
• Purified gases exiting as outlet 122 travel through means 124 for generating a negative pressure on first portion 58 of chamber 28 and are either passed to gas outlet stack 126 or recirculated by means 128 into fan 34.
• the amount of gas recirculated through means 128 is determined by adjusting flapper valve 134 by the use of threaded screw 142.
• Means 146 may be employed to mechanically turn shaft 36, holding fan 34 and rotatable member 66. In such a case, knob 150 is located to free shaft or output shaft 46 of motor 38 if any clogging occurs thereat.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Health & Medical Sciences (AREA)
• Biomedical Technology (AREA)
• Environmental & Geological Engineering (AREA)
• Analytical Chemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Gas Separation By Absorption (AREA)
• Treating Waste Gases (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=25113439

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (12)

Citations (1)

Family Cites Families (3)

• 1991
  • 1991-10-16 US US07/778,466 patent/US5185016A/en not_active Expired - Fee Related
• 1992
  • 1992-10-15 AU AU28718/92A patent/AU2871892A/en not_active Abandoned
  • 1992-10-15 JP JP5507828A patent/JPH07500282A/ja active Pending
  • 1992-10-15 WO PCT/US1992/008853 patent/WO1993007951A1/en active Application Filing
• 1993
  • 1993-02-05 TW TW082100779A patent/TW218357B/zh active

Patent Citations (1)

Also Published As

Similar Documents

Legal Events