US005402857A
`
`.
`
`[11] Patent Number:
`
`5,402,857
`
`[45]
`
`Date of Patent:
`
`Apr. 4, 1995
`
`Dresser Industries, Inc., Roots DVJ Dry Vacuum Whis-
`pair® Blowers, Nov., 1991.
`Dresser
`Industries,
`Inc., Specifications—Roots DVJ
`Whz'spaz'r® Dry Vacuum Pumps (Frames l016J, 1220J
`and Larger), Dec., 1992.
`Chicago Conveyor Corporation, Pneumatic Conveying
`Systems and Specialties, brochure.
`
`Primary Exam1'ner—Ramon S. Britts
`Assistant Exam1'ner—Frank S. Tsay
`Attorney, Agent, or Firm—Pravel, Hewitt, Kimball &
`Krieger
`'
`
`[57]
`
`ABSTRACT
`
`A method of removing drill cuttings from an oil and gas
`well drilling platform includes the steps of separating
`the drill cuttings from the well drilling fluid on the
`drilling platform so that the drilling fluids can be recy-
`cled into the well bore during drilling operations. The
`cuttingsare transmitted via gravity flow to a materials
`trough having an interior defined by sidewalls and a
`bottom portion. The drill cuttings are suctioned from
`the bottom portion of the trough interior with a first
`suction line having an intake portion that is positioned
`at the materials trough bottom. Drill cuttings are trans-
`mitted via the suction line at flow velocities in excess of
`100 feet per second to a holding tank that has an access
`opening. A vacuum is formed within the holding tank
`interior using a blower that is in fluid communication
`with the tank interior via a second vacuum line. Liquids
`and solids flowing in the vacuum lines are separated
`from the vacuum lines before the liquids and solids can
`enter the blower. The blower is powered with an elec-
`tric motor and the tank interior is sealed after being
`filled with drill cuttings to be disposed of. The tank is
`configured to be emptied via gravity flow at a remote
`disposal site by opening the access openings and allow-
`ing the cuttings to flow via gravity from the tank inte-
`rior access openings.
`
`9 Claims, 2 Drawing Sheets
`
`United States Patent
`
`[19]
`
`Dietzen
`
`[54] OIL AND GAS WELL CU'lTINGS DISPOSAL
`SYSTEM
`
`[76]
`
`Inventor: Gary H. Dietzen, P.O. Box 53652,
`Lafayette, La. 70505
`
`[21] Appl. No.: 197,727
`
`[22] Filed:
`
`. Feb. 17, 1994
`
`Int. Cl.‘ ........................ .. F21B 21/06; B09B 5/00
`[51]
`[52] U.S. Cl. .................................... .. 175/66; 175/206;
`175/207; 405/128
`[58] Field of Search ........ .; ............... 175/66, 206, 207;
`134/108
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`5/1988 Dietzen ................................ D34/39
`D. 296,027
`7/1993 Dietzen .............................. D23/202
`D. 337,809
`1/1915 Van Doren .
`1,125,413
`8/1957 Kelly ..................................... 302/17
`2,803,501
`
`..
`9/1968 Burdyn ...........
`3,400,819
`........................ 175/66
`3/1969 Burdyn et al.
`3,433,312
`3,993,359 11/1976 Sweeney ............................... 302/15
`4,019,641
`4/1977 Merz ......................... 214/14
`4,030,558
`6/1977 Morris ........
`. ... ..... 175/206 X
`4,595,422
`6/1986 Hill et al.
`175/206 X
`4,793,423 12/1988 Knol ...........
`....... 175/66
`4,878,576 11/1989 Dietzen ..................
`. 198/494
`4,942,929 7/1990 Malachosky et al.
`.
`175/66
`5,109,933
`3/1992 Jackson ..................
`175/66
`5,190,085
`3/1993 Dietzen ......
`141/98
`5,322,393
`6/1994 Lundquist ......
`406/38
`5,341,856
`8/1994 Appenzeller ...........
`141/67
`5,344,570 9/1994 McLachlan et al.
`............... .. 175/66
`
`
`
`OTHER PUBLICATIONS
`
`Max—Vac Rentals, Vacuum Skid Unit, Spec Sheet (with
`Pictures on Back).
`Dresser Industries, Inc., Specifications—Roots Vacuum
`Boosters (Frames 406DVJ thru 1220DVJ), Feb., 1988.
`
`._uslilllml
`
`-r-‘ji-
`I 53
`5/
`F I
`
`
` _
`
`
`
`DYNAMIC AIR INC.
`
`EXHIBIT 1012
`
`DYNAMIC AIR INC.
`EXHIBIT 1012
`
`

`
`U.S. Patent
`
`Apr. 4, 1995
`
`Sheet 1 of 2
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`75cos204.95
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`QV
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`QV
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`1:mm H
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`\.Q\u\
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`

`
`U.S. Patent
`
`Apr. 4, 1995
`
`Sheet 2 of 2
`
`5,402,857
`
`11-
`|L__'!i
`1'
`
`50
`5
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`i
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`/4
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`J
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`G5
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`66
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`'_sf=_i
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`1576. 2
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`

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`1
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`5,402,857
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`2
`
`OIL AND GAS WELL CUITINGS DISPOSAL
`SYSTEM
`
`BACKGROUND OF THE INVENTION
`1. Field of the Invention
`
`The present invention relates to the disposal of oil
`and gas well cuttings such as are generated during the
`drilling of an oil and gas well using a drill bit connected
`to an elongated drill string that is comprised of a num-
`ber of pipe sections connected together, wherein a fluid
`drilling mud carries well cuttings from the drill bit
`through a well annulus and to a solids removal area at
`the well head for separating well cuttings from the
`drilling mud. Even more particularly, the present inven-
`tion relates to an improved well cuttings disposal sys-
`tem that collects oil and gas well cuttings in a transport-
`able tank that is subjected to a vacuum (l6”-25" mer-
`cury) formed with a motor driven blower that moves
`about 300-1300 cubic feet per minute of air containing
`cuttings, and in relatively small hoses to generate flow
`velocities of between about 100-300 feet/sec.
`2. General Background
`In the drilling of oil and gas wells, a drill bit is used to
`dig many thousands of feet into the earth’s crust. Oil
`rigs typically employ a derrick that extends above the
`well drilling platform and which can support joint after
`joint of drill pipe connected end to end during the dril-
`ling operation. As the drill bit is pushed farther and
`farther into the earth, additional pipe joints are added to
`the ever lengthening “string” or “drill string”. The drill
`pipe or drill string thus comprises a plurality ofjoints of
`pipe, each of which has an internal, longitudinally ex-
`tending bore for carrying fluid drilling mud from the
`well drilling platform through the drill string and to a
`drill bit supported at the lower or distal end of the drill
`string.
`Drilling mud lubricates the drill bit and carries away
`well cuttings generated by the drill bit as it digs deeper.
`The cuttings are carried in a return flow stream of dril-
`ling mud through the well annulus and back to the well
`drilling platform at the earth’s surface. When the dril-
`ling mud reaches the surface, it is contaminated with
`these small pieces of shale and rock which are known in
`the industry as well cuttings or drill cuttings.
`Well cuttings have in the past been separated from
`the reusable drilling mud with commercially available
`separators that are know as “shale shakers”. Some shale
`shakers are designed to filter coarse material from the
`drilling mud while other shale shakers are designed to
`remove finer particles from the well drilling mud. After
`separating well cuttings therefrom, the drilling mud is
`returned to a mud pit where it can be supplemented
`and/or treated prior to transmission back into the well
`bore via the drill string and to the drill bit to repeat the
`process.
`The disposal of shale and cuttings is a complex envi-
`ronmental problem. Drill cuttings contain not only the
`mud product which would contaminate the surround-
`ing environment, but also can contain oil that is particu-
`larly hazardous to the environment, especially when
`drilling in a marine environment.
`In the Gulf of Mexico for example, there are hun-
`dreds of drilling platforms that drill for oil and gas by
`drilling into the subsea floor. These drilling platforms
`can be in many hundreds of feet of water. In such a
`marine environment, the water is typically crystal clear
`and filled with marine life that cannot tolerate the dis-
`
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`posal of drill cuttings waste such as that containing a
`combination of shale, drilling mud, oil, and the like.
`Therefore, there is a need for a simple, yet workable
`solution to the problem of disposing of oil and gas well
`cuttings in an offshore marine environment and in other
`fragile environments where oil and gas well drilling
`occurs.
`
`Traditional methods of cuttings disposal have been
`dumping, bucket
`transport, cumbersome conveyor
`belts, and washing techniques
`that
`require large
`amounts of water. Adding water creates additional
`problems of added volume and bulk, messiness, and
`transport problems. Installing conveyors requires major
`modification to the rig area and involves many installa-
`tion hours and very high cost.
`
`SUMMARY OF THE INVENTION
`
`The present invention provides an improved method
`and apparatus for removing drill cuttings from an oil
`and gas well drilling platform that uses a drill bit sup-
`ported with an elongated, hollow drill string. Well dril-
`ling fluid (typically referred to as drilling mud) that
`travels through the drill string to the drill bit during a
`digging of a well bore. The method first includes the
`step of separating well drilling fluid from the waste drill -
`cuttings on the drilling platform so that the drilling fluid
`can be recycled into the well bore during drilling opera-
`tions. The drill cuttings fall via gravity from solid sepa-
`rators (e.g. shale shakers) into a material trough. At the
`material trough, cuttings are suctioned with an elon-
`gated suction line having an intake portion positioned in
`the materials trough to intake well cuttings as they
`accumulate.
`
`The drill cuttings are transmitted via the suction line
`to a holding tank that has an access opening. A vacuum
`is formed within the holding tank interior using a
`blower that is in fluid communication with the tank
`interior via a second vacuum line.
`
`Liquids (drilling mud residue) and solids (well cut-
`tings) are separated from the vacuum line at the tank
`before the liquids and solids can enter the blower.
`The blower is powered with an electric motor drive,
`to reach a vacuum of between about sixteen and twenty-
`five inches of mercury. The vacuum line is sized to
`generate speeds of between about one hundred and
`three hundred feet per second.
`The tank is sealed after the interior is filled with drill
`cuttings to be disposed of. The tank is emptied of drill
`cuttings at a desired remote disposal site by opening the
`access opening to allow gravity flow of the cuttings
`from the tank interior via the access opening.
`In the preferred embodiment, three suction lines are
`used including a first line that communicates between
`the materials trough and the holding tank, a second
`suction line that extends between theholding tank and
`a separator skid, and a third suction line that communi-
`cates between the separator skid and blower.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`65
`
`For a further understanding of the nature and objects
`of the present invention, reference should be had to the
`‘following detailed description,
`taken in conjunction
`with the accompanying drawings, in which like parts
`are given like reference numerals, and wherein:
`FIG. 1 is a schematic view of the preferred embodi-
`ment of the apparatus of the present invention; and
`
`

`
`3
`FIG. 2 is a schematic view of an alternate embodi-
`ment of the apparatus of the present invention.
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`
`In FIG. 1, there can be seen a well cuttings disposal
`system 10 of the present invention. Well cut1:ings dis-
`posal system 10 is used in combination with a material
`trough that collects solids falling via gravity from a
`plurality of solids separator units. Material troughs per
`second are known in the art, typically as a catch basin
`for cuttings. The material trough 11 defines an area that
`is a receptacle for solids containing some residual dril-
`ling mud. Cuttings have been collected from the well
`bore after the drilling mud has been transmitted through
`the drill string to the drill bit and then back to the sur-
`face via the well armulus.
`-
`
`At the material trough, there are a plurality of coarse
`shakers 12, 13 and a plurality of fine shakers 14, 15. The
`shakers 12, 13, and 14, 15 are commercially available.
`Coarse shakers 12, 13 are manufactured under and sold
`under the mark “BRANDT” and fine shakers are sold
`under the mark “DERRICK”. Shakers 12-15 channel
`away the desirable drilling mud to a mud pit. The well
`cuttings fall via gravity into trough -11. It is known in
`the prior art to channel away drilling mud that is to be
`recycled, and to allow well cuttings to fall from shale
`shakers via gravity into a receptacle. Such as been the
`case on oil and gas well drilling rigs for many years.
`_
`Interior 16 of trough 11 catches cuttings that have
`fallen from shakers 12, 15. The trough 11 thus defines an
`interior 16 having a plurality of inclined walls 17, 18
`that communicate with a trough bottom 19. Walls 17, 18
`can be teflon covered to enhance travel of material to
`bottom 19.
`
`Trough bottom 19 includes a discharge opening 20
`that communicates with discharge conduit 21. The
`opening 20 is typically sealed during operation with a
`closure plate (not shown).
`A first suction line 22 is positioned to communicate
`with the interior 16 portion of trough 11. First suction
`line 22 thus provides an inlet 23 end portion and an
`opposite end portion that communicates with collection
`tank 24. Tank 24 collects solid material and some liquid
`(e.g. residual drilling mud on the cuttings) as will be
`described more fully hereinafter.
`Collection tank 24 has a bottom 25, a plurality of four
`generally rectangular side walls 27, and a generally
`rectangular top 28. A pair of spaced apart fork lift sock-
`ets 26 allow tank 24 to be lifted and transported about
`the rig floor and to a position adjacent a crane or other
`lifting device.
`A plurality of lifting eyes 29, 31 are provided includ-
`ing eyes 29, 30 on the top of tank 24 and lifting eye 31
`on the side thereof near bottom 25.
`
`The lifting eyes 29 and 30 are horizontally positioned
`at end portions of the tank top 28. This allows the tank
`to be lifted with a crane, spreader bar, or other lifting
`means for transferral between a marine vessel such as a
`work boat and the drilling rig platform. In FIG. 1, the
`tank 24 is in such a generally horizontal position that is
`the orientation during use and during transfer between
`the rig platform and a remote location on shore, for
`example.
`The lifting eyes 30, 31 are used for emptying the tank
`24 after it is filled with cuttings to be disposed of. When
`the tank is to be emptied, a spreader bar and a plurality
`of lifting lines are used for attachment to lifting eyes 30,
`
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`5,402,857
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`4
`31. This supports the tank in a position that places lifting
`eye 29 and lifting eye 30 in a vertical line. In this posi-
`tion, the hatch 34 is removed so that the cuttings can be
`discharged via gravity flow from opening 30 and into a
`disposal site.
`During a suctioning of well cuttings from materials
`trough 11, the suction line 22 intakes cuttings at inlet 23.
`These cuttings travel via line 22 to outlet 38 which
`communicates with coupling 36 of tank 24. Flow takes
`place from inlet 23 to outlet 38 because a vacuum is
`formed within the hollow interior of tank 24 after
`hatches 34, 35 are sealed. The vacuum is produced by
`using second suction line 40 that communicates via
`separators 43, 45 with third suction line 51 and blower
`57.
`
`Second suction line 41 connects at discharge 39 to
`coupling 37 of hatch 35. The opposite end of suction
`line 40 connects at end portion 41 via coupling 42 to fine
`separator 43. A second fines separator 45 is connected
`to separator 43 at spoolpiece 44. The two separators 43
`and 45 are housed on a structural separator skid 46 that
`includes lifting eyes 47, 48 and fork lift sockets 49 for
`transporting the skid 46 in a maimer similar to the trans-
`port of tank 24 as aforedescribed.
`Third suction line 51 connects to effluent line 50 that
`is the discharge line from separator 45. End portion 52
`of third suction line 51 connects to effluent line 50 at a
`flange, removable connection for example. The three
`suction lines 22, 40, 51 are preferably between three and
`six inches in internal diameter, and are coupled with
`blower 57 generating about 300-1500 CFM of air flow,
`to generate flow desired velocities of about 100-300 feet
`per second that desirably move the shale cuttings
`through suction line 22. The suction lines are preferably
`flexible hoses of oil resistant PVC or can be Teflon
`coated rubber. Quick connect fittings are used to con-
`nect each suction line at its ends.
`End portion 53 of third section line 51 also connects
`via a flanged coupling, for example,
`to blower 57.
`Blower 57 and its motor drive 58 are contained on
`power skid 54. Power skid 54 also includes a control
`box 59 for activating and deactivating the motor drive
`58 and blower 57. The power skid 54 provides a plural-
`ity of lifting eyes 55, 56 to allow the power skid 54 to be
`transported from a work boat or the like to a well dril-
`ling platform using a lifting harness and crane that are
`typically found on such rigs.
`Each of the units including tank 24, separator skid 46,
`and power skid 54 can be lifted from a work boat or the
`like using a crane and transported to the rig platform
`deck which can be for example. 100 feet above the water
`surface in a marine environment.
`In FIG. 2, an alternate embodiment of the apparatus
`of the present invention is disclosed designated gener-
`ally by the numeral 60. In FIG. 2, the tank 24 is similarly
`constructed to that of the preferred embodiment of
`FIG. 1. However, in FIG. 2, the well cuttings disposal
`system 60 includes a support 61 that supports a screw
`conveyor 62 and its associated trough 63. The trough 63
`and screw conveyor 62 are sealed at opening 70 in
`trough 63 using hatch 71. Trough 63 is positioned at an
`intake end portion of screw conveyor while the oppo-
`site end portion of screw conveyor 62 provides a dis-
`charged end portion 64 that communicates with dis-
`charge shoot 69. Chute 69 empties into opening 32
`when hatch 34 is open during use, as shown in FIG. 2.
`The screw conveyor 62 is driven by motor drive 65
`that can include a reduction gear box 66 for example,
`
`

`
`5,402,857
`
`-continued
`PARTS LIST
`Description
`Part Number
`drive belt
`67
`arrow
`68
`discharge chute
`69
`opening
`70
`hatch
`71
`top
`72
`side wall
`73
`bottom
`74
`screw conveyor outer wall
`75
`
`76 spring loaded door
`
`
`
`Because many varying and different embodiments
`may be made within the scope of the inventive concept
`herein taught, and because many modifications may be
`made in the embodiments herein detailed in accordance
`with the descriptive requirement of the law, it is to be
`understood that the details herein are to be interpreted
`as illustrative and not in a limiting sense.
`What is claimed as invention is:
`
`1. A method of removing drill cuttings from an oil
`and gas well drilling platform that uses a drill bit sup-
`ported with a drill string and a well drilling fluid during
`a digging of a well bore, comprising the steps of:
`a) separating drill cuttings from the well drilling fluid
`on the drilling platform so that the drilling fluid can
`be recycled into the well bore during drilling oper-
`ations;
`b) transmitting the cuttings via gravity flow to a
`materials trough having an interior defined by side
`walls and a bottom portion;
`c) suctioning the separated drill cuttings with a first
`suction line having an intake end portion that is
`positioned at the materials trough bottom portion;
`(1) transmitting the drill cuttings via first the suction
`line to a holding tank that has at least one access
`opening for communicating with the tank interior;
`e) forming a vacuum within the holding tank interior
`with a blower that is in fluid communication with
`the tank interior via a second vacuum line;
`f) separating liquids and solids from the first and sec-
`ond vacuum lines before said liquids and solids can
`enter the blower;
`g) powering the blower with an electric motor;
`h) sealing the tank after the interior is filled with drill
`cuttings to be disposed of; and
`i) emptying the tank of drill cuttings at a desired
`disposal site by opening the access opening to
`allow gravity flow of the cuttings from the tank
`interior via one of the access openings.
`2. The method of claim 1 wherein in step “d”, the
`holding tank access opening is covered with a hatch
`that has inlet and outlet fittings connectable respec-
`tively to the first and second suction lines.
`3. The method of claim 1 wherein the flow velocity in
`the first suction line is about one hundred to three hun-
`dred (100-300) feet per second.
`4. The method of claim 1 further comprising the step
`of transporting the tank to and from the well drilling
`platform using a forklift.
`5. The method of claim 1 further comprising the step
`of transporting the holding tank to and from the drilling
`platform using a lifting device that attaches to lifting
`eyes on the outside surface of the holding tank.
`6. The method of claim 1 wherein in step “i”, liquids
`and solids are separated from the first suction line at the
`
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`5
`and a drive belt 67. Arrow 68 in FIG. 2 shows the flow
`path of coarse cuttings that are discharged via first
`suction lines 22 into opening 70 and trough 63. The
`sidewall and bottom 74 of trough 63 communicate and
`form a seal with screw conveyor outer wall 75 so that
`when a vacuum is applied using second suction line 40,
`cuttings can be suctioned from trough 11 at intake 23 as
`with the preferred embodiment. The -conveyor 62
`forcebly pushes the drill cuttings toward discharge end
`64. A spring activated door 76 is placed in chute 69.
`When material backs up above door 76,
`the door
`quickly opens under the weight of cuttings in chute 69.
`Once the cuttings pass door 76, the door shuts to main-
`tain the vacuum inside trough 73, and screw conveyor
`62, thus enabling continuous vacuuming.
`The following table lists the parts numbers and parts
`descriptions as used herein and in the drawings attached
`hereto.
`
`
`
`Part Number
`10
`11
`12
`13
`14
`15
`16
`17
`18
`19
`20
`21
`22
`23
`24
`25
`26
`27
`28
`29
`30
`31
`32
`33
`34
`35
`36
`37
`38
`39
`40
`41
`42
`43
`44
`45
`46
`47
`48
`49
`50
`51
`52
`53
`54
`55
`56
`57
`58
`59
`60
`61
`62
`63
`64
`65
`66
`
`PARTS LIST
`Description
`well cuttings disposal system
`material trough
`coarse shaker
`coarse shaker
`fine shaker
`fine shaker
`reservoir
`inclined wall
`inclined wall
`trough bottom
`discharge opening
`conduit
`first suction line
`inlet
`collection tank
`bottom
`fork lift socket
`side wall
`top
`lifting eye
`lifting eye
`lifting eye
`opening
`opening
`hatch
`hatch
`coupling
`coupling
`outlet
`discharge
`second suction line
`end
`coupling
`separator
`spoolpiece
`separator
`separator skid
`lifting eye
`lifting eye
`fork lift socket
`effluent line
`third suction line
`end
`end
`power skid
`lifting eye
`lifting eye
`blower
`motor drive
`control box
`well cuttings disposal system
`support
`screw conveyor
`trough
`discharge end portion
`motor drive
`gearbox
`
`

`
`7
`holding tank and liquids and solids are separated from
`the second suction line at a separator that is positioned
`in fluid communication with the second vacuum line
`upstream of the blower.
`7. The method of claim 1 wherein in step “g”, the
`blower generates fluid flow in the vacuum lines of be-
`tween about
`three hundred and fifteen hundred
`(300-1500) cubic feet per minute.
`8. The method of claim 1 where in the vacuum
`formed within the tank in step “e” is between about
`sixteen and twenty-five (16-25) inches of mercury.
`9. A method of removing drill cuttings from an oil
`and gas well drilling platform that uses a drill bit sup-
`ported with a drill string and a well drilling fluid during
`a digging of a well bore, comprising the steps of:
`a) separating drill cuttings from the majority of the
`well drilling fluid on the drilling platform so that
`the drilling fluids can be recycled into the well
`bore during drilling operations;
`b) transmitting the cuttings via gravity flow to a
`materials trough having an interior defined by side
`walls and a bottom portion wherein the cuttings
`
`8
`are at least partially coated with some residue of
`the well drilling fluid;
`c) suctioning the separated drill cuttings with a first
`suction line having an intake end portion that is
`positioned at the materials trough bottom portion;
`d) transmitting the drill cuttings via the first suction
`line at a flow velocity in excess of one hundred feet
`per second to a holding tank that has at least one
`access opening for communicating with the tank
`interior;
`e) forming a vacuum within the holding tank interior
`with a blower that is in fluid communication with
`the tank interior via a second vacuum line;
`f) separating the drill cuttings and at least some of the
`drilling fluid residue from the first and second vac-
`uum lines before same can enter the blower;
`g) powering the blower with an electric motor;
`h) sealing the tank after the interior is filled with drill
`cuttings to be disposed of; and
`i) emptying the tank of drill cuttings at a desired
`disposal site by opening the access opening to
`allow gravity flow of the cuttings from the tank
`interior via one of the access openings.
`*
`*
`*
`*
`*
`
`5,402,857
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`45
`
`50
`
`55
`
`60
`
`65