New technology to recover oil-based mud overcomes ultrafines challenge

A technology to recover oil-based mud (OBM) has met with success in Canada and North Dakota, saving clients from $1,000 to $10,000 per day by overcoming a shortfall in shaker design, according to Dan Pomerleau, president of FP Marangoni. “With the first external manifolds installed on M-I SWACO Mongoose shakers, the client recovered $6,600 of OBM within the first 24 hours,” Mr Pomerleau said.  The technology was first marketed in June 2010; use of the system has grown to 45 systems in Canada, and in North Dakota use of the system has increased from one to 15 rigs since November 2010.

“The VAC-Screen Drilling Recovery System was borne out of a client request to get control of losses at surface. Prior to developing the system, we first tried a rotary vacuum system from the US to meet the client request, but the recovered mud was so full of ultrafines that when reintroduced into the drilling fluid it ruined the rheological properties of the fluid,” Mr Pomerleau said.

FP Marangoni set out to develop a system that would perform the loss-control function at the shaker. The VAC-Screen Drilling Recovery System, which can recover any type of drilling fluid, requires a vacuum unit and a recovery tank (typically 6-15 bbl) that is rented as part of the package. The vacuum unit is plugged into the rig’s selective catalytic reduction unit for electrical power. The vacuum manifold can be mounted internally or externally, depending on the type of shaker.

“The most important advantage of the system is to recover drilling fluid every day and to give your customer that volume back. One of the major concerns about fluid loss recovery technology is ultrafines. Is the fluid that is recovered going to in any way damage the fluid system?” Mr Pomerleau said. “Our system does not create fines, which addresses this issue.”

According to Mr Pomerleau, his clients generally need to recover only 2 bbl of OBM a day to recover the cost of system rental. “The technologies we compete against cost anywhere from $3,500 to $4,500 a day. Also, we’ve seen that chemical costs on oil muds have gone down as a result of recovering the chemicals off the cuttings. Oil emulsifiers are polar by nature; so when you remove the oil mud from the cuttings in this chemical-rich environment, the chemicals return along with the mud. Further, by removing oil from cuttings, this reduces the need to mix drying materials with oil-mud cuttings to make them stable for transport.”

Operation of the recovery system involves attaching a vacuum manifold under the shaker screen or installing a vacuum manifold that has a shaker screen attached to it. The system is attached to the shaker’s vibrating basket so the manifold vibrates with the shaker as it is running. Attached to the manifold is a vacuum line with a fluid/air separator; this is connected to the vacuum collection tank. The vacuum unit is installed as close as possible to the shaker to keep the distance that the recovered fluid is transported as short as possible.

Mr Pomerleau believes the technology also “gives operators a sizable advantage in meeting progressively more stringent environmental regulations for cuttings disposal.”