Patent Application
20080083566
A more particular description of embodiments of the invention briefly summarized above may be had by references to the embodiments which are shown in the drawings which form a part of this specification. These drawings illustrate certain preferred embodiments and are not to be used to improperly limit the scope of the invention which may have other equally effective or equivalent embodiments.
Presently preferred embodiments of the invention are shown in the above-identified figures and described in detail below. It should be understood that the appended drawings and description herein are of preferred embodiments and are not intended to limit the invention or the appended claims. On the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims. In showing and describing the preferred embodiments, like or identical reference numerals are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
As used herein and throughout all the various portions (and headings) of this patent, the terms “invention”, “present invention” and variations thereof mean one or more embodiment, and are not intended to mean the claimed invention of any particular appended claim(s) or all of the appended claims. Accordingly, the subject or topic of each such reference is not automatically or necessarily part of, or required by, any particular claim(s) merely because of such reference.
As shown in
A sensor SR on the line A senses moisture content of the material in the line and conveys this information to a control system CS (e.g., but not limited to a control system as disclosed in the co-owned patents and U.S. patent applications listed above) which can shut down flow from the system 12. The control system CS controls the various items, devices and apparatuses in the system 10 and, in one aspect, communicates with a control system CM of a cuttings reinjection system CRI. The control system CS can adjust the flow rate of dried material to a blender 24 using a standard PID algorithm with a setpoint based on acceptable density, feedback for which is obtained from a meter of the CRI system.
Material in a line B is conveyed to the blender 24. Water (or sea water) from a tank 22 is circulated in lines D and C to the blender 24 by a pump 23. The pump 23 pumps liquid from the tank 22 which mixes with the inflowing air flow from the line B in the blender 24. A viscosity/density meter 28 provides the control system CS with information regarding the viscosity and density of the material flowing from the tank 22. The cuttings material and water mix together and are pumped by the pump 23 through a screen 21 into the tank 22 of a first stage 20 of the system 10.
Water (or sea water) as needed is fed into the tank 22 by a pumping system 25. An agitator 26 helps maintain solids in suspension in the tank 22.
Density (and weight) and viscosity of the mixture in the tank 22 are sensed by sensors (e.g. meter 28, sensor ST) which convey sensed levels of density, weight, and viscosity to the control system CS, and, as needed, are adjusted by changing the feed from the system 14 using a control system CS 2 for the system 14 with the control system CS in communication with the control system CS 2. A resulting slurry of the material is pumped by a pump 27 in a line E to a line G to a tank 32 or, optionally, first to a shaker system 34. A control valve 29 selectively controls flow in the line G. When the tank's contents are at an acceptable density and/or viscosity, the valve 29 is opened, flow in Line B ceases, and the tank is emptied into the line G sending a batch of material to the tank 32. The shaker system 34 removes oversize solids returned in a line F back to the tank 22; and drilling fluid with particles of material of an acceptable size (which pass through the shaker's screens) is fed in a line H to the tank 32 of a second stage 30. Sensors SS sense levels of density, weight and viscosity of the material in the tank 32 and convey this information to the control system CS. As needed, weight and viscosity are adjusted. An agitator 36 agitates the contents of the tank 32. A discharge rate of the system 14 is adjustable via adjusting a variable speed metering screw 14a of the system 14.
Drilling fluid is pumped in lines I, J and K by a pump 33 for injection into a wellbore W e.g., for drilling operations employing pumped drilling fluid with valves VA and VB closed and valve VC open. Optionally, the pump 33 pumps material to the cuttings reinjection (“CRI”) system which may include a or several first stage booster pump(s) for a or several triplex pump(s) or similar pump(s) useful in cuttings reinjection.
Optionally, with valves VA and VC closed, the material from the tank 32 is pumped by the pump 33 in the line I, J, L to a storage facility T. Optionally with the valves VA and VC closed, the pump 33 pumps material from the tank 32 in the lines I, J, M back into the tank 32 for storage and/or further processing.
Any suitable known blender or mixer can be used for the blender 24 (e.g. a high shear mixing unit or mixer). In one aspect, as shown in
As shown in
In one particular aspect the dryer 130 is a vortex dryer, e.g. a commercially available National Oilwell Varco Brandt Vortex Dryer which, optionally, can be flushed with liquid material from the holding tank 150 via lines 201, 202, 203. Via lines 201, 202 and 204 material from the tank 150 is fed to the centrifuge 160. Solids output by the centrifuge 160 flow in a line 205 to a conveyor 206 which transfers the solids in a line 207 to the container 140. The holding tank 150 is a weir tank with a middle weir dividing the tank into two sides 151, 152.
The feed conveyor 110 feeds material in a line 208 to the container 140 and in a line 209 to the dryer 130. Recovered material flows from the dryer 130 to the tank 150 in a line 215. Drilling fluid from the centrifuge 160 flows in a line 211 back to the tank 150. Reusable drilling fluid flows from the tank 150 in a line 212 to a rig mud system 210. Optionally, this fluid flows through a filtration system FL prior to introduction to the system 210. Material in a line 214 from a side 151 of the tank 150 is fed back to the centrifuge in a line 201. Material flows in a line 213 to the line 212. A pump 218 pumps material in the line 201.
The system 170, which receives dry material from the dryer 130, including a positive pressure pneumatic conveying system, including, e.g., those disclosed in the two U.S. patents and the pending U.S. patent application referred to above. Dry material from the dryer 130 is fed by the reversible conveyor 220 to the system 170 in lines 223, 224. A moisture meter 230 measures the moisture level of material from the dryer 230 and, if the material's moisture content exceeds a pre-set level (e.g. 10% by weight)—a level at which conveyance by the positive pressure pneumatic conveying apparatus would be impeded or prevented—the reversible conveyor 220 reverses and the material is fed in the lines 221, 222 to the container 140. In one aspect the dryer is a vortex dryer that produces the dry cuttings material as dry powder in lean phase.
Suitable valves, check valves, filters, flow controllers and controls for them are used on the lines of the system 100.
Dry material from the system 170 is moved, in one aspect, to a suitable storage and processing system, e.g. a tank system 180 which may be any tank or vessel (or tanks or vessels) disclosed in the two U.S. patents and the U.S. patent application referred to above, including a vessel (land-based; on a rig; on a ship) which doses material to an apparatus or system (e.g. to the system 190 or to the system 196). The reinjection systems 190 and 196 may be like that of
In one particular aspect, if the moisture sensor 230 indicates that screens in the dryer 130 are blinding (indicating the moisture content of the material is too high for the conveying system to convey or to effectively convey the material), material from the dryer 130 is directed in the line 222 to the container 140. Optionally, material from the system 170 is fed to a thermal treatment system 197 (from which it can then be transferred to the system 190 or to a transport for transfer to the system 196. As with the transfer of material to the system 190, material can be sent directly from the system 170 to the system 197, or to the system 180 and then to the system 197.
The present invention, therefore, provides in some, but not necessarily all, embodiments a method for reclaiming component materials from a drill cuttings mixture of drilling fluid and cuttings material, the method including: flowing a drill cuttings mixture of drilling fluid and cuttings material to a dryer; producing with the dryer dry cuttings material; and conveying with a conveyor system the dry cuttings material to a secondary system, the conveyor system including a positive pressure pneumatic conveying apparatus for conveying the dry cuttings material to the secondary system. Such a method may include one or some, in any possible combination, of the following: wherein the secondary system is a cuttings reinjection system, the method further including reinjecting the dry cuttings material into a wellbore using the cuttings reinjection system; sensing moisture content of the dry cuttings material; if the moisture content indicates that the dry cuttings material will impede conveyance by the conveyor system, diverting the dry cuttings material away from the positive pressure pneumatic conveying apparatus; producing with the dryer a drilling fluid mixture with some solids from the drill cuttings mixture, and flowing the produced drilling fluid mixture from the dryer with some solids to a holding system; flowing the drilling fluid mixture from the holding system to a rig mud system; flowing drilling fluid mixture from the holding system to a centrifuge for processing by the centrifuge to produce centrifuged solids and centrifuged drilling fluid; flowing the centrifuged drilling fluid to the holding system; the conveyor system including a reversible conveyor, the method further including reversing the reversible conveyor to prevent dry drill solids from the dryer from flowing to the positive pressure conveying apparatus; wherein the secondary system is a thermal treatment system, the method further including treating the dry cuttings material with the thermal treatment system; dosing material from the positive pressure pneumatic conveying apparatus to the secondary system; wherein a primary control system controls operations of the system and a secondary control system controls the cuttings reinjection system, the secondary control system in communication with the primary control system, the method further including adjusting using the primary control system a rate of feed of material to a mixer, and feeding material from the mixer to the cuttings reinjection system; wherein the secondary control system provides density measurements from a density meter to the primary control system, the primary control system taking said measurements into account in said adjusting; wherein the cuttings material includes pieces of material, each piece having a size, the method further including the dryer reducing the size of said pieces; and/or wherein the dryer reduces the pieces to powder.
The present invention, therefore, provides in some, but not necessarily all, embodiments a method for reclaiming component materials from a drill cuttings mixture of drilling fluid and cuttings material, the method including: flowing a drill cuttings mixture of drilling fluid and cuttings material to a dryer; producing with the dryer dry cuttings material; conveying with a conveyor system the dry cuttings material to a reinjection system, the conveyor system including a positive pressure pneumatic conveying apparatus for conveying the dry cuttings material; reinjecting the dry cuttings material into a wellbore using the reinjection system; sensing moisture content of the dry cuttings material; the conveyor system having a reversible conveyor, the method further including if the moisture content of the dry cuttings material is of such a level that conveyance by the conveyor system would be impeded, reversing the reversible conveyor to prevent dry cuttings material from the dryer from flowing to the positive pressure conveying apparatus.
The present invention, therefore, provides in some, but not necessarily all, embodiments a system for separating drilling mixture components and for reinjecting cuttings material into a wellbore, the system including: a dryer for producing dry cuttings material from a cuttings mixture of drilling fluid and cuttings material; a conveying system for conveying the dry cuttings material to a reinjection apparatus, the conveying system having positive pressure pneumatic conveying apparatus; and a thermal treatment apparatus or a reinjection apparatus for reinjecting the dry cuttings material into a wellbore. Such a method may include one or some, in any possible combination, of the following: a moisture sensor for sensing moisture content of the dry cuttings material, and the conveyor system further having a reversible conveyor, the reversible conveyor for feeding the dry cuttings material to the positive pressure pneumatic conveying apparatus and for reversing, if the moisture content of the dry cuttings material is such that conveyance by the positive pressure pneumatic conveying apparatus would be impeded, so that the dry cuttings material do not flow to the positive pressure pneumatic conveying apparatus; a centrifuge for receiving a drilling fluid stream from the dryer, the drilling fluid stream containing reclaimable drilling fluid, and the centrifuge for processing the drilling fluid stream from the dryer producing reusable drilling fluid; and/or wherein the dryer is for reducing in size the size of pieces of cuttings material, in one aspect, to powder.
In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited herein is to be understood as referring to the step literally and/or to all equivalent elements or steps. This specification is intended to cover the invention as broadly as legally possible in whatever form it may be utilized. All patents and applications identified herein are incorporated fully herein for all purposes.
