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Case Study: RHE-USE System Reduces Waste Volume and Saves USD 1 Million in Project Costs, Canada

Chemically enhanced centrifugation method efficiently treats and reconditions drilling fluid to remove low-gravity solids before reuse

Challenge: Develop a cost-effective method for reusing drilling fluids by reducing or removing performance-limiting low-gravity solids.

Solution: Use the RHE-USE two-stage centrifuge system to chemically treat and efficiently remove low-gravity solids from drilling fluid.

Result: Reduced waste volume by more than 3,125 bbl [500 m3] with a 67% cost savings and drilling fluid treatment savings greater than 47% per cubic meter for a combined project savings of more than USD 1 million.

Decrease oilfield waste and improve fluid quality for reuse

Offshore St. John’s, Newfoundland, an operator sought a more efficient and economical method for eliminating low-gravity solids from drilling fluid and handling oilfield waste. When looking to reuse drilling fluid, if an oil- or synthetic-base fluid cannot be reused, the operator must dispose of the fluid by reinjection, properly discharge it offshore, or transport it to a shore-based waste management facility for disposal.

The greatest challenge in reusing drilling fluid is the accumulation of colloidal low-gravity solids. Any solids not removed will be circulated through the downhole assembly, where they will be reduced in size, making them more difficult to be removed mechanically. This process can impair tool function and mobility and add to the wear and tear on tools and pumps. Storage is an alternative but can be costly because the fluid must periodically be agitated to keep the solids suspended before reuse.

Deploy RHE-USE system to significantly reduce low-gravity solids content

To meet solids management requirements, M-I SWACO recommended using the RHE-USE system, which combines staged centrifugation and chemically enhanced treatment. The treatment enables enhanced flocculation and separation of extremely low-gravity solids so that the fluid can be cleaned more efficiently by centrifugation. With minimal chemical additions, and coupled with the RHE-USE system performing solids removal, fluid is circulated through the system and solids less than 2 um are removed.

A mud plant at the M-I SWACO facility in St. John’s was used to treat the fluid from the RHE-USE system and laboratory testing of the treated fluid was performed throughout the project. An initial fluid volume (Set A) was used for testing to perfect treatment concentrations, temperature, and centrifuge settings. This 950-bbl [152-m3] fluid volume was treated with different concentrations of water, brine, and base oil in 15 batches through a 518 HV high-volume, high-speed decanting centrifuge.

Communication between the laboratory, wellsite, and office personnel enabled quick and seamless alterations of treatment between batches, resulting in a quick solution for efficient treatment and reconditioning of the drilling fluid. The mixing procedure was applied to a second batch (Set B) of fluid, 806 bbl [129 m3], which was treated through a CD-500 HV high-volume, high-speed precision-balanced centrifuge in 14 batches. This procedure improved the efficiency of chemical use while providing consistent results with only two circulations through the system. To complete the project, a third batch (Set C) of fluid, 2,500 bbl [400 m3], was treated through a CD-500 HV centrifuge.

Reduced cost per cubic meter of drilling fluid and waste volume

At the conclusion of the project, the combined fluid from each batch was mixed and tested in the laboratory. Fluid volume Set A was found to contain 4.28% low-gravity solids after treatment, while fluid volume Set B contained 3.34% and fluid volume Set C contained 3.71%. The percent change in low-gravity solids, based on each volume of fluid and the corresponding baseline, was approximately 7%.

Data analysis indicated the waste volume was reduced by more than 3,125 bbl with a 67% cost savings in waste management. Optimization of the treatment process saved more than an estimated 47% per cubic meter of drilling fluid. When combined with the waste volume reduction, the overall cost savings exceeded USD 1 million.


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RHE-USE System Reduces Waste Volume and Saves USD 1 Million in Project Costs, CanadaRHE-USE System Reduces Waste Volume and Saves USD 1 Million in Project Costs, CanadaRHE-USE System Reduces Waste Volume and Saves USD 1 Million in Project Costs, Canada
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Reduced Waste Equals Reduced Well Cost

RHE-USE technology allows operators to reuse invert emulsion drilling fluids over multiple wells without relying on reclamation through high rates of dilution. Visit RHE-USE Fluid Processing System page