Abstract:
Methods and apparatus are provided for the uninterrupted transfer of oil and gas well drill cuttings from a collection point, such as a shale shaker trough, to several types of variously configured on rig and off rig receptacles. Two or more hoppers are arranged for alternating receipt and discharge of cuttings, the cuttings being continuously drawn to the hoppers by a suction force from an upstream blower. The receptacles utilized in the various embodiments are varied, such as barges, box containers, and slurry units. The hoppers are, in some embodiments, moved to remote locations, such as off rig barges, prior to beginning the cuttings transfer.

Description:
BACKGROUND OF THE INVENTION 
     In oil and gas well drilling operations, drilling fluid is circulated through the drill string, returning formation drill cuttings to the surface through the annulus. The formation drill cuttings are removed from the drilling fluid so that the drill fluid may be reused. A &#34;shale shaker&#34; is typically used for this purpose, which results in drill cuttings accumulating in a trough. The accumulated drill cuttings must be removed from the trough and appropriate disposal must be arranged. 
     Several methods for removing drill cuttings from the shale shaker trough are known, including various configurations of conveyors, chutes, suction lines, tanks, and other devices. Industry experience has shown that the utilization of a suction line provides several benefits not found in other methods including easier installation, quicker installation, less moving parts, improved safety, lower maintenance, and reduced expense. 
     Current methods and apparatus utilized in the suction line methods suffer, among other things, from an inability to dispose of the suctioned drill cuttings without interrupting the suction force. This causes substantial delays, and attempts to address this problem have not proven satisfactory. 
     One known method of utilizing a suction line to remove drill cuttings from the shale shaker trough, involves a tank in which a suction is created, drawing drill cuttings into the tank until full. Once full, however, the suction force must be broken, the suction force connection equipment must be removed from the tank, and the tank must be sealed for removal and replacement by an empty tank. This method in particular has been known to cause substantial delays. Another method involves a single hopper in which a suction force is created, again drawing drill cuttings into the hopper until full. This method also suffers in that the suction force must be terminated in order for the hopper to be opened for discharge of the accumulated drill cuttings. 
     Known suction line methods also suffer from an inability to properly and efficiently adapt to various methods of disposing of the drill cuttings once they have been removed from the shale shaker trough. For example, although the suction line method utilizing a single hopper can be configured to discharge from the single hopper into a &#34;slurrification unit,&#34; the method does not appropriately address the presence of two receiving tanks on most of such slurry units. A slurrification unit typically has two circulating systems, each involving the formulation of a slurry consisting of water and the drill cuttings, with the slurry being circulated, and the cuttings ground to a sufficiently small size for ultimate discharge to an injection pump. The injection pump forces the slurry down the well for reintroduction into porous formations. Any suction line method having only a single hopper discharging into only one slurrification unit tank, fails to take full advantage of the capabilities of the two tank slurrification unit dual circulating systems. 
     Methods and apparatus are needed which will provide suction line retrieval of drill cuttings from the shale shaker trough, provide continuous suction force in the system, enable efficient post-suction collection and disposal of the drill cuttings, and fully complement the two tank slurrification unit system. 
     SUMMARY OF THE INVENTION 
     Our invention provides methods and apparatus for suctioning drill cuttings from a shale shaker trough, using a continuous suction force in the system, and further enabling efficient post-suction collection and disposal of the drill cuttings. Such methods and apparatus are fully complementary to a slurrification unit system having two tanks and two corresponding circulation systems. 
     Our suctioning method involves a suction force which pulls cuttings from the shale shaker trough. The cuttings are pulled, in an alternative fashion, to a first hopper and then a second hopper. When a hopper has the appropriate amount of drill cuttings accumulated within it, suction is broken within that hopper only, and the cuttings are discharged into one or more receptacles. In a similar manner, suction is broken in the other hopper when it has received the appropriate amount of drill cuttings, followed by cuttings discharge. These steps are timed such that the first hopper discharges cuttings while the second hopper is filling and the second hopper discharges cuttings while the first hopper is filling. 
     Our suctioning method can be accomplished such that the suctioning force is continuously present at the shale shaker trough, and in either the first or the second hopper. It can also be accomplished such that the receipt of cuttings into the first hopper, the breaking of the suction force in the second hopper, and the discharge of cuttings from the second hopper begin simultaneously, or substantially simultaneously, and similarly, that the receipt of cuttings into the second hopper, the breaking of the suction force in the first hopper, and the discharge of cuttings from the first hopper also begin simultaneously, or substantially simultaneously. A blower provides the suction force, and our invention includes the capturing of any liquids in the air after the air leaves the hoppers, but before it reaches the blower. 
     Our invention includes several improved methods of receiving suctioned drill cuttings after the first post-suction accumulation. For example, the two hoppers can be spaced and located in appropriate proximity to a &#34;train&#34; of receptacles, such that the filled receptacle can be moved and replaced by an empty receptacle during a period of non-discharge from our two hopper system. This exchange of receptacles can be accomplished with no cessation of the suctioning force. Embodiments such as this can be readily utilized both onshore and offshore. 
     Our invention also provides for the reception of discharged drill cuttings from the first hopper into a first receptacle and from the second hopper into a second receptacle. With the hopper so configured, a two &#34;train&#34; system for moving and replacing receptacles is provided. 
     Our invention also includes the movement of the two hoppers from a first discharge location to a second discharge location, such that a different receptacle is being filled at each location. This multiple receptacle method allows the movement and replacement of a filled container while the hoppers are above a different container. 
     Also included as a method in our invention is the spacing of the first and second hoppers for even distribution of the discharged drill cuttings into a receptacle. 
     Our invention includes the positioning of the hoppers off of the drilling rig prior to receiving drill cuttings. This allows the discharge of the drill cuttings from the hoppers to occur in a wide variety of receptacles, such as barges, other ships with storage compartments, trucks, etc. 
     Our invention is particularly adaptable to compartmentalized receptacles. The hoppers can be spaced such that the first and second hoppers coincide with pairs of compartments within a single receptacle. Furthermore, the hoppers can be moved in such a fashion as to analogously coincide with additional pairs of compartments. Moving such a receptacle with respect to stationary hoppers is also included. 
     Our invention also provides for the hoppers to be mounted on, and moved along, guide fixtures and combinations of guide frames and guide fixtures. This allows the placement of cuttings in an evenly distributed fashion in single opening receptacles, and also allows movement between compartments on compartmentalized receptacles, e.g. barges. Both lateral and longitudinal movement is provided, as well as, independent movement of the hoppers with respect to each other. Mounting each hopper on an independent guide fixture is also included. 
     Our invention also includes the routing of the discharged cuttings from the two hoppers to a common point for further routing. Such further routing can be along a single path or can be divided into two or more paths, for alternate discharge routing into two or more receptacles. Our invention includes both a redirectable single discharge routing and a dual discharge routing, both of which will be particularly adaptable to the two tank slurrification unit system. In this application, the combined discharged cuttings from both hoppers would be first directed to the slurrification unit first tank, and at an appropriate time, redirected to the slurrification unit second tank. For this purpose our invention includes various configurations of chutes and screw conveyors. Our invention also includes the further treatment of the cuttings with subsequent discharge and injection into porous formations in the wellbore. The slurrification unit operation, can be performed with two isolated circulating systems, as well as, a commingled system, in which case the two slurrification unit circulation systems share either all or part of the slurried cuttings. 
     Furthermore, our invention improves the method of discharging the cuttings from both hoppers into a single slurrification unit tank without subsequent redirection. Prior methods, having only one hopper, required that the suction force at the shale shaker trough be terminated during the discharge of cuttings from the hopper. In our invention, this suction force can be continuous. 
     Our invention also includes the movement of the two hoppers for discharge, first into the slurrification unit first tank, and then to the slurrification unit second tank. 
     In the many configurations involving the slurrification unit, our invention also includes the step of filtering the discharge from such slurry units, catching oversized particles and recirculating them for further grinding. 
     Our invention includes the use of more than two hoppers, with method and apparatus variations and adaptations which correspond to analogous variations and adaptations described for two hoppers. 
     Our invention includes apparatus for moving drill cuttings from a cuttings collection point to one or more receptacles, which comprises a first and second hopper, each hopper having a cuttings inlet, an air outlet, and a cuttings discharge outlet, a common suction line having a first end and a second end, a first independent suction line and a second independent suction line, the first independent suction line being in suction communication with the first hopper cuttings inlet and a common suction line second end, the second end suction line being in suction communication with the second hopper cuttings inlet and the common suction line second end, suction force means (or suction force introduction means), a common exit line, having a first and a second end, the common exit line first end being in suction communication with the suction force means such that the suction force means creates a suction force in the common exit line, a first independent exit line and a second independent exit line, the first independent exit line being in suction communication with the common exit line second end and the first hopper air outlet, the second independent exit line being in suction communication with the common exit line second end and the second hopper air outlet, suction alternating means such that the suction force means repeatedly creates a suction force in one of the first or second hoppers, then the other of the first or second hoppers, but in only one of such hoppers at any one instant, the suction force drawing drill cuttings through the common suction line first end, when the common suction line first end is placed in proximity to drill cuttings in the cuttings collection point, and a first hopper discharge valve and a second hopper discharge valve for allowing cuttings to be respectively discharged from the first and second hoppers during intervals in which no suction force is present in the discharging hopper. 
     Our invention also includes such apparatus wherein the first hopper discharge valve, the second hopper discharge valve, and the suction alternating means are coordinated such that the opening of the first hopper discharge valve and the termination of the suction force in the first hopper begin simultaneously, or substantially simultaneously, and the opening of the second hopper discharge valve and the termination of the suction force in the second hopper begin simultaneously, or substantially simultaneously. 
     Preferred embodiments of our invention include the configuration of the suction alternating means such that the suction force is continuously present in either the first or second hopper; or, in another embodiment, that the suction force is continuously present at the cuttings collection point, i.e. at the common suction line first end. 
     In a preferred embodiment of our invention, the suction alternating means includes a diverter valve positioned on the common suction line such that suction communication between the common suction line and either of the first or the second independent suction lines can be broken, the diverter valve being interconnected with the first independent exit line valve, the second independent exit line valve, the first hopper discharge valve, and the second hopper discharge valve, such that, when the first independent exit line closes, the second independent exit line valve opens, the first hopper discharge valve opens, the second hopper discharge valve closes, and the diverter valve breaks suction communication with the first independent suction line, and further such that, when the first independent exit line valve opens, the second independent exit line closes, the first hopper discharge valve closes, the second hopper discharge valve opens, and the diverter valve breaks suction communication with the second independent suction line. 
     In another embodiment, the first independent exit line valve, the second independent exit line valve, the first hopper discharge valve, and the second hopper discharge valve are interconnected such that, when the first independent exit line closes, the second independent exit line valve opens, the first hopper discharge valve opens, and the second hopper discharge valve closes, and further such that, when the first independent exit line valve opens, the second independent exit line valve closes, the first hopper discharge valve closes, and the second hopper discharge valve opens. 
     In another embodiment, the suction alternating means includes a suction-operated first independent suction line valve and a suction-operated second independent suction line valve, the first independent suction line valve closing the first independent suction line when a suction force is in the second independent suction line, the second independent suction line valve closing the second independent suction line when a suction force is in the first independent suction line. 
     In another embodiment, the first and second hopper discharge valve, each comprised a hinged flap, hinge with respect to the hopper cuttings discharge outlets, such that the hinge flap closes the hopper cuttings discharge outlet when a suction force is present within the hopper. 
     Our invention also includes a vibrator for both hoppers, which causes the cuttings to discharge more freely. Similarly, one or more air jets are included for agitating and dislodging cuttings from the interior walls of the first and second hoppers. Such air jets can be postponed to effect a circumferential pattern. 
     A clean out access hatch is also provided for both the first and second hoppers. 
     Our invention also comprises a hopper guide frame, the hopper guide frame being configured to support and secure the first and second hoppers, the hopper guide frame further having one or more tracks with the first and second hoppers being movable along these tracks. The movement of the first and second hoppers may be independent. 
     Another embodiment of our invention includes a hopper support frame where the hopper support frame is configured to support and secure one or more hoppers, and a hopper support frame guide fixture which is sized and configured such that it supports the hopper support frame. This hopper support frame guide fixture has one or more tracks and the hopper support frame is attached to such tracks such that the hopper support frame is movable along the hopper support frame guide fixture tracks. Our invention also includes additional hopper support frames on the hopper support frame guide fixture, as well as, two or more hopper support frames on two or more hopper support frame guide fixtures. Powered movement and direction of the hoppers and the hopper support frame is also provided. 
     In another embodiment, longitudinally expandable first and second independent suction lines and exit lines are also included which will allow a variable space between the first and second hoppers. 
     In our invention, when the formation drill cuttings have collected in the shale shaker trough, a suction force is created in a common suction line having an end in such drill cuttings, the common suction line then dividing into a first independent suction line and a second independent suction line, these lines being in suction communication with a first hopper and a second hopper respectively, the first and second hoppers being in suction communication with a first independent exit line and a second independent exit line respectively, the first and second independent exit lines joining to form a common exit line which extends ultimately to a suction-creatingblower, the first and second exit lines, common exit line and blower being in suction communication. The suction force in the first hopper is removed by closing a first independent exit line valve and breaking suction communication between the first independent suction line and the common suction line. The suction force in the second hopper is initiated by opening a second independent line valve. Drill cuttings are then received from the common suction line, through the second independent suction line, into the second hopper, until the desired amount of drill cuttings are in the second hopper. The suction force is then removed from the second hopper by closing a second independent exit line valve and breaking suction communication between the second independent suction line and the common suction line. Drill cuttings are discharged from the second hopper through a second hopper discharge opening by opening a second hopper discharge opening valve. The suction force in the first hopper is initiated by opening the first independent exit line valve and restoring suction communication between the first independent suction line and the common suction line. Drill cuttings are received from the common suction line, through the first independent suction line, into the first hopper, until the desired amount of drill cuttings are in the first hopper. The suction force is removed from the first hopper by closing the first independent exit line valve and isolating the first independent suction line from the common suction line. Drill cuttings are discharged from the first hopper through a first hopper discharge opening by opening a first hopper discharge opening valve. These steps are repeated for as many cycles as necessary to accommodate the volume of drill cuttings which must be addressed. 
     Our invention includes, in a preferred embodiment, that the steps of closing the first independent exit line valve, breaking suction communication between the first independent suction line and the common suction line, opening the first hopper discharge opening valve, and opening the second independent exit line occur simultaneously, or substantially simultaneously, and that the steps of closing the second independent exit line valve, breaking suction communication between the second independent suction line and the common suction line, opening the second hopper discharge opening valve, and closing the first independent exit line valve occur simultaneously, or substantially simultaneously. 
     In another embodiment the common suction line is eliminated and the first independent suction line and the second independent suction line both extend to the cuttings collection point, i.e. the shale shaker trough. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic representation of the drill cuttings transfer system. 
     FIG. 2 is a top view of the dual hopper portion of the system. 
     FIG. 3 is a side view of the dual hopper portion of the system. 
     FIG. 4 is a schematic representation of an embodiment of the system in use on a jack-up rig, with a barge for a receptacle. 
     FIG. 5 is a side view of the rig and barge in FIG. 4 
     FIG. 6 is an end view of the barge with the dual hopper portion of the system in place. 
     FIG. 7 is a top view of the barge with the dual hopper portion of the system in place. 
     FIG. 8 is a schematic representation of an embodiment of the invention where the system is utilized on a jack-up rig with a barge. 
     FIG. 9 is a side view of the rig and barge in FIG. 8. 
     FIG. 10 is a top view schematic representation of an embodiment of the invention utilized on an offshore rig, with several barges in position to be serviced. 
     FIG. 11 is a top view schematic representation of an on rig utilization of the system, with containers depicted. 
     FIG. 12 is a top view of the dual hopper portion of the system with the related structure for servicing the containers in FIG. 11. 
     FIG. 13 is a side view of the application depicted in FIG. 13. 
     FIG. 14 is a top view schematic representation of the on rig utilization of the system in FIG. 11, with the equipment reoriented in order to fill two containers simultaneously. 
     FIG. 15 is a side view of the application in FIG. 14. 
     FIG. 16 is a side view schematic representation of an embodiment of the invention in which the structure allows movement of the hoppers with respect to each other. 
     FIG. 17 is a schematic representation of an embodiment of the invention in which two tanks of a slurrification unit receive cuttings from the dual hopper portion of the system. 
     FIG. 18 is a schematic representation of an embodiment of the invention in which two tanks of a slurrification unit receive cuttings from the dual hopper portion of the system. 
     FIG. 19 is a schematic indicating the electrical and pneumatic circuits which control the valves and vibrators in the dual hopper portion of the system. 
    
    
     DESCRIPTION 
     A drill cuttings transfer system 10 is depicted in FIG. 1. Drill cuttings accumulate in a cuttings collection point 12, normally the trough associated with a shale shaker. The suction force in a common suction line 14 draws the cuttings into the common suction line 14 first end 16. At the common suction line 14 second end 18, the cuttings are diverted to either of a first independent suction line 20 or a second independent suction line 22. In a preferred embodiment shown in FIG. 1, the common suction line 14 is flexible. 
     A first and second hopper 24,26 each have a cuttings inlet 28,30, air outlets 32,34, and cuttings discharge outlets 36,38. Air and cuttings are received into the first and second hoppers 24,26 through the cuttings inlets 28,30. Within the hopper, the cuttings are cyclonically separated. The air exits the first and second hoppers 24,26 through the air outlets 32,34, while the cuttings accumulate within the first and second hoppers 24,26 through the cuttings discharge outlets 36,38. 
     The FIG. 1 embodiment includes a pneumatically operated common suction line diverter valve which allows cuttings to enter only one of the first or second independent suction lines 20,22 at a time. The DGP Pneumatic diverter valve by Bush &amp; Wilton Valves, Inc., is a satisfactory choice to accomplish this result, although simpler combinations of flaps, check valves, and even manually operated ball valves, gate valves, etc., can also accomplish the same result. First and second independent exit lines 42,44 receive air from the air outlets 32,34, and in the embodiment depicted in FIG. 1, a pneumatically operated three-way valve 46 is situated with respect to such exit lines 42,44 such that air is being withdrawn from only one of the first and second hoppers 24,26, at a time. FIGS. 2-3 provide additional views showing the placement of the three-way valve 46 with respect to air outlets 32,34. The first and second independent exit lines 42,44 merge to form a common exit line 48. The common exit line 48, in the embodiment depicted in FIG. 1, is in suction communication with a scrubber 50 for a final separation of solids in the form of fines, from the air, prior to the air being drawn into the blower 52. 
     The three-way valve function an be executed by several well-known combinations of valves and actuating cylinders. In the embodiment shown in FIG. 1, they three-way valve 46 includes two butterfly valves, an actuating cylinder, pneumatic lines, and T-linkage linking the valves. 
     The scrubber 50 provides a vertical path for the air allowing any liquid to fall to the bottom. A scrubber outlet valve is connected to a float which closes the valve when liquids in the scrubber 50 reach a predetermined level. 
     It is anticipated that the blower 52 will be sized at approximately 3,000 cfm and be powered by a 125 HP electric motor. It is anticipated that the blower 52, or other suction creating devices, will be sized to form a continuous vacuum at 15 inches of mercury, and an intermittent vacuum at 22 inches of mercury. The Roots 624 RCS positive rotary lobe blower will satisfactorily perform this function. 
     In the embodiment depicted in FIG. 1, the accumulated cuttings in first and second hoppers 24,26 exit through cuttings discharge outlets 36,38 when such outlets 36,38 are opened using cuttings discharge outlet valves 54,56. The pneumatically operated SB Series, SBT-Pneumatic (twin cylinder) slide valve by Bush &amp; Wilton Valves, Inc., is satisfactory for this application. The cuttings discharge is enhanced by the use of pneumatically operated vibrators 58,60 placed in the vicinity of the cuttings discharge outlets 36,38 on each of the first and second hoppers 24,26. The &#34;MARTIN&#34; &#34;VIBROLLER&#34; vibrator, Model UCVR4-.05 is satisfactory for this application. 
     The common exit line 48 is flexible in the embodiment depicted in FIG. 1. 
     The first and second hoppers 24,26 are secured by a frame 58 in the embodiment depicted in FIG. 1. This frame 58 can be shaped and configured to enable numerous configurations and applications of this system 10. 
     In the embodiment depicted in FIG. 1, the first and second hoppers 24,26 are generally cyclonic and can-shaped, having a cone-shaped discharge and an elliptical head. 
     A timer, or manual operation, can be utilized to coordinate the operation of the three-way valve 46, the cuttings discharge outlet valves 54,56 and the common suction line diverter valve 40 in a manner such that the suction force is continuously present in either the first or the second hopper 24,26 continuously present at the cuttings collection point 12, and at the required openings and closings of such valves 40,46,54,56 occur simultaneously, or substantially simultaneously. A preferred embodiment is shown in the FIG. 19 schematic in which the valves 40,46,54,56 are coordinated such that the system 10 is in one of two modes of operation, at all times, but not simultaneously. In the first mode, the common suction line diverter valve 40 opens the first independent suction line 20 and closes the second independent suction line 22, the three-way valve 46 opens the first independent exit line 42 and closes the second independent exit line 44, the first hopper cuttings discharge outlet valve 54 is closed and the second hopper cuttings discharge outlet valve 56 is open. In this first mode, cuttings are being drawn through the first independent suction line 20 into the first hopper 24, where they accumulate as the air exits through the first independent exit line 42. Any cuttings in the second hopper 26 will fall, or will have fallen, through the open second hopper cuttings discharge outlet 38. 
     In the second mode, the common suction line diverter valve 40 closes the first independent suction line 20 and opens the second independent suction line 22, the three-way valve 46 closes the first independent exit line 42 and opens the second independent exit line 44, the first hopper cuttings discharge outlet valve 54 is open and the second hopper cuttings discharge outlet valve 56 is closed. In this second mode, cuttings are being drawn through the second independent suction line 22 into the second hopper 26, where they accumulate as the air exits through the second independent exit line 44. Any cuttings in the first hopper 24 will fall, or will have fallen, through the open first hopper cuttings discharge outlet 36. 
     Although most embodiments are readily adaptable to interconnected and fully automated valve combinations, it is also contemplated within our invention, that manual operation of some or all of the valves is feasible. 
     The drill cuttings transfer system 10 is readily adaptable to numerous applications in both the onshore and offshore drilling environments. FIGS. 4-7 depict various views of an offshore drilling environment involving a jack-up rig 100, a barge 102, and several compartments 104 for storing cuttings on the barge 102, the compartments 104 being open-topped. Symbolic representations of certain components of the system 10 are also depicted. In this preferred embodiment, the hopper frame 58 is positioned on cross members 106 which span the width of the barge 102, the cross members 106 having rollers 108, the rollers 108 being situated along tracks 110, such that the cross members 106 can move along the length of the barge 102. In other embodiments, it is also contemplated that a similar roller and track arrangement could be provided to allow lateral movement of the frame 58 with respect to the length of the barge 102. In all cases, a variety of common devices could be utilized to power the movement of the hoppers 24,26 with respect to the barge 102, with remote control operation included. Freestanding diesel motors, electric motors, and other power sources can be readily adapted through ordinary automotive coupling arrangements. The frame 58, or the cross member 106 and frame 58 combination, can be placed and removed by a crane. FIG. 10 is an example of the adaptability of the system 10 to a multi-barge 102 situation, where the barges can be conveniently placed adjacent the rig 100 and still be filled due to the flexibility of the system 10. FIG. 10 also depicts variations contemplated with respect to the position of the frame 58, the cross members 106, and the barge 102. 
     FIGS. 8-9 depict embodiments of the invention in which the first and second hoppers 24,26 are independently movable along the tracks 110 in a barge 102 application. 
     FIGS. 11-13 depict an additional embodiment in which the system 10 fills containers on the rig surface in an offshore drilling environment. In this embodiment, the frame 58 is placed upon a elevated structure which allows containers 152 to be moved to a position beneath the frame 58 such that the cuttings can be discharged into the containers 152. The containers 152 can be skidded or rolled into appropriate positions beneath the structure 150 and the frame 58 to enable an efficient distribution of the cuttings within the container 152. The containers 152 can be of the type with open tops, sliding door tops, etc. When removed from the other end of the structure 150 the containers 152 can be removed by a crane. 
     FIGS. 14-15 depict an embodiment of the invention in which the frame 58 and structure 150 are oriented such that two containers 152 can be positioned beneath the structure 150, each container 152 being filled by a different hopper 24,26. 
     FIG. 16 depicts an embodiment of the invention in which the first and second hoppers 24,26 can be moved with respect to each other, the variable spacing of the hoppers 24,26 allowing optimum distribution of the cuttings within a container 152. 
     FIGS. 17-18 depict embodiments whereby the system 10 is coordinated with a two-tank slurrification unit 200. Slurry units 200 receive cuttings into one or more tanks 202,204 form a slurry using a liquid, usually salt water, circulating the slurry, and grinding the cuttings in the slurry during the circulation process. The slurry containing the appropriately ground cuttings is discharged from the slurrification unit 200 for disposal into the wellbore for injection into an appropriate subsurface formation. One or more holding tanks 206 usually receive the slurry in preparation for injection pumping. 
     In a slurrification unit 200 application, FIG. 17 depicts the discharge chutes 208,210 which receive cuttings from the first and second hopper cuttings discharge outlets 36,38. A cuttings discharge chute diverter 212 diverts the cuttings to either or both of the slurrification unit tanks 202,204. FIG. 18 depicts the application whereby the cuttings discharge chutes 208,210 direct the cuttings to a common articulated chute 214, the common articulated chute 214 being positioned to direct the cuttings to either of the slurrification unit tanks 202,204. 
     In another embodiment, both the first and second hoppers 24,26 can be positioned to discharge directly into only one of the slurrification unit tanks 202,204. Similarly, in another embodiment, both the first and second hoppers 24,26 discharge cuttings into either one of the slurrification unit tanks 202,204, or a screw conveyor apparatus for directing all or part of the cuttings to the other slurrification unit tank 202,204. 
     The reader&#39;s attention is directed to all papers and documents which are filed concurrently with or previous to this specification, in connection with this application, and which are open to public inspection with this specification. The contents of all such papers and documents are incorporated herein by reference. 
     Although the present invention has been described in considerable detail with reference to certain preferred and alternate embodiments thereof, other embodiments are possible. Accordingly, the spirit and scope of the claims should not be limited to the description of the embodiments contained herein.