Systems and Methods for Managing Cuttings Using Eddy Pump and Tank

Abstract

Systems and methods for handling fluid discharged from an oilfield drilling operation including cuttings and other waste products are disclosed. An eddy pump is coupled to a tank with a controller for dispensing a predefined quantity of fluid to a truck, dryer, or another suitable receptacle. The controller causes a precise quantity of fluid to be dispensed and can deliver a weight ticket to an operator which reduces the risk of too heavy a load causing a fine or too light a load to cause inefficiencies.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present document is based on and claims priority to U.S. Provisional Application Ser. No. 62/673,105, filed on May 17, 2018, which is incorporated herein by reference in its entirety.

BACKGROUND

Drilling operations produce some waste products, such as cuttings, which require some precise handling and disposal. These cuttings can include shaker cuttings which are typically 20-40% liquid content by volume and/or centrifuge cuttings which are 40-60% liquid by volume due to the small size of the centrifuge cuttings and the high volume of surface area. Solids control technicians typically operate excavators at the drill site, which can compromise their ability to operate the solids control system. Some operators have minimal training which can present a risk for accidents and damaged equipment. Dump trucks with lined beds transport the cuttings to disposal facilities. There is a need for efficient, safe, and effective systems and methods for handling cuttings and other waste products.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an eddy tank system according to embodiments of the present disclosure.

FIG. 2 shows a system for disposing of cuttings and fluid using a dryer according to embodiments of the present disclosure.

FIG. 3 is a top view of a system for handling a fluid-solids mixture using an eddy pump according to embodiments of the present disclosure.

FIG. 4 is a block diagram depicting a method for handling a fluid/solids mixture using an eddy pump according to embodiments of the present disclosure.

DETAILED DESCRIPTION

Below is a detailed description according to various embodiments of the present disclosure. The eddy tank utilizes an eddy pump which has been used in the dredging industry to move solids slurries. The design of the eddy pump efficiently moves the solids without the need for free liquid. The eddy pump may include a housing and an impeller in the housing. The robust impeller creates an eddy in the fluid just in front of the impeller. This vortex pulls low pressure at the suction of the eddy pump which aids in priming the eddy pump. As the solids move through the eddy pump without touching the impeller, the wear is greatly reduced when compared to a centrifugal pump. There is generally between 1-9 inches of clearance between the impeller and the housing which helps to allow a fluid vortex to move the solids/fluid mixture through the pipe and reduces wear and corrosion.

The tank arrangement is designed to hold 200-250 barrels of cuttings waste. This capacity allows for the logistics of trucks to arrive, load, and remove the solids from location in a timely manner. The tank will be designed with a recirculation loop that will allow the pump to homogenize the cuttings and allow for a controlled volume to be diverted from the loop to a truck, bin, or secondary processing loop.

By adding a secondary screening device, grinder, and viscosity control, the system is conducive for feeding an injection system. The Eddy tank is a suitable pump and tank for controlling a slurry utilized for downhole injection.

In some embodiments, the system can include a smaller catch bin and/or pump that is configured to feed a dryer as there would be no need to hold truck load volumes. The systems can be designed with level sensors, flow sensors, and automated control valves that will decrease the need for supervision and labor. Additionally, a PLC (programmable logic controller) can monitor and record performance data for daily and end of well reports. The tank design can be effective in a land market, and a smaller bin design (25-50 barrels) can be used for offshore applications.

In some embodiments, the systems and methods of the present disclosure are configured to automate the system to improve total cost of ownership by providing an automated maintenance control system to reduce the need for personnel. In some embodiments, the systems and methods of the present disclosure enable a solids control technician to operate the unloading and feeding to other systems with a programed control loop that operates, monitors for issues, maintains, and records the data with a minimum effort.

In further embodiments, the systems and methods of the present disclosure can be easily transported with a mobile skid design under the tank or with wheels or other suitable transport mechanisms. In some embodiments the eddy pump can be designed on a porch adjacent to the tank and be fitted with a redundant pump that would engage in the event of an upset that would shut down the first pump.

FIG. 1 shows an eddy tank system 10 according to embodiments of the present disclosure. The system 10 includes an eddy pump 12 and an auger tank 14 with the eddy pump 12 operatively coupled to the auger tank 14 such that the eddy pump 12 moves the fluid in the auger tank 14, including any solid material such as cuttings that may be in the auger tank 14. The system 10 can also include shakers 16 which are positioned over the auger tank 14 to allow fluid to fall into the auger tank 14. There can be any number of shakers 16.

The system 10 can be used in place of an excavator (not shown) and the day/night operators who man the excavator. The eddy pump 12 is mounted to the auger tank 14 and can be configured to remove cuttings in the 60-70% dry range in some embodiments. In some embodiments, the eddy pump 12 can be configured to remove cuttings in the 60-80% dry range. The eddy tank 12 can include a housing 11 and an impeller 13 in the housing 11. In some embodiments, there is between 1 inch and 9 inches of clearance between the impeller 13 and the housing 11. The auger tank 14 can include an auger 15 that can push the cuttings into the eddy pump 12. The eddy pump 12 has an output line 13 into which the eddy pump 12 delivers the fluid-cuttings mixture. The output line 13 can be positioned to deliver the fluid-cuttings mixture to any desired location for further handling and processing.

In some embodiments, the system 10 further includes a recirculation loop 18 that can remix with the cuttings in the fluid, resulting in a homogenous blend. In some embodiments, the system 10 is to be used to feed a cuttings dryer or other component with a limited intake capacity. For example, some dryers have a limit of 50 gallons per minute. A valve 20 can be added to the recirculation loop 18 to divert a certain flow toward the dryer and recirculate the remainder or to direct the remainder to another treatment option.

In some embodiments, the system 10 includes a programmable logic controller (PLC) 22 and several measuring and control devices such as automated control valves, flow sensors, torque monitors, density monitoring, and a weigh station. The PLC 22 can be configured to interface with these devices via a wired or wireless connection to precisely control how the system 10 operates. For example, the PLC 22 may be configured to interface with one or more sensing mechanisms 23 (e.g., flow sensors, density sensors, etc.) to sense fluid properties of the mixture. The sensing mechanisms 23 may be located at various points in the system 10.

Conventional techniques require an operator and/or excavator to load trucks. The truck is loaded and many times the individual responsible for loading the truck will not have precise information about the weight of the load and will therefore err on the side of caution and under-load the truck because the driver is afraid of getting stopped and fined for being overweight. The operator is charged for a full load and throughout the course of the well the difference in these missed loads can be thousands of dollars. The systems and methods of the present disclosure ensure the operator is paying for a full load and the driver has a weigh ticket and is assured of a legal load on the highway.

The PLC 22 and associated sensors, and scales can be automated and the solids control technician only has to initiate the sequence once the solids control technician is assured the truck and loading boom are in alignment. Daily records are kept and end of well performance recaps are tabulated to assure performance to the operator. Many operators don't know the waste volume on their well as sometimes trucking companies bill 30 days late which is after the well is drilled and the books are closed.

The electrical motors, controls, and sensors can be designed to Class 1 Division 2 standards. The auger tank 14 can be equipped with load hitches that allow the auger tank 14 to be quickly loaded and moved to a new location. Hose sections that are equipped with jet lines and can be quickly purged if a sensor determines a line plugging incident is occurring. Minimal jetting of fluid is required to unplug lines as automated sensors catch bridging faster than control room human counterparts. The flush liquid is only added to the plugging line.

Grating with ingress hatches are mounted to the surface of the auger tank 14 to prevent items being dropped into the tank and or personnel entry. Handrails are mounted around the auger tank 14 to prevent falls with kick plate to prevent dropping of parts and tools. Any maintenance of the eddy pump 12 or auger tank 14 involves a lockout tagout procedure to prevent accidental starting of the system.

The system 10 can include a loading boom 24 that directs fluid output from the auger tank 14. The loading boom 24 can deliver the fluid to any desired location, such as an external receptacle (e.g., truck) or another piping system or another treatment solution. The truck shown in FIG. 1 is positioned on a load scale 26 which weighs the truck and the contents of the load. Automating the fluid delivery and weighing the truck will result in a more accurate and therefore efficient waste disposal system.

FIG. 2 shows a system 30 for disposing of cuttings and fluid using a dryer 32 according to embodiments of the present disclosure. The system 30 can include an auger tank 14, an eddy pump 12, and shakers 16 similar to the system shown in FIG. 1. The output line 13 in this embodiment is coupled to the dryer 32 which receives the fluid-solids mixture. In some embodiments, a valve 20 directs a portion of the mixture to the dryer as limited by the capabilities of the dryer. A recirculation loop 18 can direct the remainder of the fluid into the auger tank 14. The dryer 32 can include a centrifuge 33, a cuttings dryer 34, and a dry solids holding tank 35. These components can further process the cuttings and dispose of them as desired.

FIG. 3 is a top view of a system 40 for handling a fluid-solids mixture using an eddy pump according to embodiments of the present disclosure. The system 40 includes shakers 16, an eddy pump 12, an auger tank 14, and an output line 13. A disposal system 42 is coupled to the output line 13 and is configured to receive and treat the cuttings and fluid mixture.

FIG. 4 is a block diagram depicting a method 50 for handling a fluid/solids mixture using an eddy pump according to embodiments of the present disclosure. The method 50 can be executed using the systems and methods shown and described elsewhere herein such as in FIGS. 1-3. At 52, a truck operator arrives with a truck to be filled with a fluid/solids mixture. The operator can initiate the process using a button or another suitable initiation mechanism which may include passing the capacity of the truck as a parameter. In some embodiments, the loading station can be equipped with measuring capabilities that can measure the truck's capacity on the spot. In still other embodiments, the loading station can communicate with the truck via RFID or other wireless or wired communication mechanisms by which the loading station can receive a capacity parameter.

At 54, the fluid/solids mixture is deposited into the truck. At 56, the truck continues to be filled while one or more of the following conditions is met. One condition is that the truck capacity is not yet reached (truck not full). This condition can be based on the capacity parameter achieved through one of the various ways described above at 52. Another condition is that sufficient fluid/solids mixture remains in the tank to be delivered. Yet another condition is that the fluid parameters are within tolerance. The systems delivering the fluid/solids mixture to the truck can include various sensors and measuring components such as level sensors, fluid/solid mixture concentration sensing mechanisms, scales, metering valves, etc. Virtually any parameter can be monitored and the filling of the truck can be dependent upon the parameters. For example, if a truck needs to have a certain percentage of solids in the mixture, if the mixture deviates from this percentage by more than a predetermined amount, the delivery can be halted and/or a warning can be given.

At 58, once the conditions for terminating delivery are met, the loading station can terminate delivery of fluid/solids mixture. At 60, a weight ticket can be printed or otherwise delivered to the operator to enable the operator to know precisely the weight of the load. This helps to avoid costly fines for overages, and the inefficiency of under-loading the truck. These systems can be automated and run by a controller such as a PLC or other suitable computing device which can be local to the loading station or can be managed via a remote communication link.

Claims

1. A system, comprising:

a tank configured to receive a mixture of fluids and solids from an oilfield drilling operation, wherein the mixture is between 60% and 80% dry;

an eddy pump operatively coupled to the tank and configured to move the mixture from the tank into an external receptacle;

an auger in the tank configured to move the mixture toward the eddy pump;

sensing mechanisms configured to sense fluid properties of the mixture; and

a controller operatively coupled to the eddy pump, the auger, and the sensing mechanisms, wherein the controller is configured to operate the eddy pump and the auger to deliver a desired quantity of the mixture to the external receptacle.

2. The system of claim 1, wherein the eddy pump comprises a housing and an impeller in the housing, wherein there is between 1 inch and 9 inches of clearance between the impeller and the housing.

3. The system of claim 1, wherein the controller is configured to receive instructions for a quantity of fluid to deliver to the external receptacle.

4. The system of claim 1, wherein the external receptacle comprises a dryer.

5. The system of claim 1, further comprising a recirculating loop operatively coupled to the eddy pump, wherein the recirculating loop is configured to direct a predefined portion of the fluid pumped by the eddy pump back into the tank.

6. A method, comprising:

storing a mixture of fluids and solids received from an oilfield drilling operation containing cuttings that is between 60% and 80% dry;

receiving a parameter for a quantity of the mixture to be delivered to an external receptacle;

monitoring a fluid property of the mixture;

while the fluid property of the mixture is within a predetermined acceptable range, delivering the mixture to the external receptacle using an eddy pump until the quantity of mixture has been delivered to the external receptacle; and

delivering a weight ticket describing a weight of the mixture delivered to the external receptacle.

7. The method of claim 6, wherein the weight of the mixture is derived from the fluid property and the quantity of the mixture.

8. The method of claim 6, wherein the eddy pump comprises a housing and an impeller in the housing, wherein there is between 1 inch and 9 inches of clearance between the impeller and the housing.