December 2004 Supplement    Rig Floor Equipment

Bulk mixer system eliminates hopper

The Bulk Mixer System (BMS), provided by Bulk Mixer Inc., West Monroe, Louisiana, eliminates the need for a hopper in bulk mud applications, following industry’s continued re-engineering around the hopper.

The BMS technology addresses multiple rig problems resulting from use of a hopper to prepare drilling fluids. Present methods for mixing mud on rigs consist of hands-on lifting and cutting of 50-lb paper sacks of dry chemicals. Sacks are emptied into a hopper device intended to combine the dry chemical powders with liquid additives at the bottom of a funnel-shaped receptacle. However, a choke point at the bottom of the hopper is created as volume/ viscosity of the drilling fluid increases, and resulting mixing is slow and incomplete. The mud produced does not perform at the rig as it does in the lab; waste is created; and workers are exposed to unnecessary health/ safety risks.

The new system employs a large, sealed, self-cleaning mixing tank – similar to a kitchen blender, but with a 200-bbl capacity. Bulk barite, gel and cement can be added directly to the mixer and be downhole, to the active mud pit or to the cementing unit, in a matter of minutes.

The BMS rolls over the entire contents three times per minute, completely shearing and mixing all material inside the tank, ensuring both quality and speed of delivery – as much as 10 times faster than the hopper method, and with lab-quality results. This mixing technology makes drilling more efficient, cutting days off drilling time and substantially cutting costs, particularly on deepwater rigs.

The system is dust-free. All transfers of dry powders into the mixer are enclosed in piping. There is no need for dust collection add-on equipment. Moving of the dry product to and from the mixer is automated, so there is no worker lifting of heavy sacks or buckets. The rig stays cleaner, so slip-and-fall hazards are eliminated.

Bulk Mixer provides dust-free rig floor environment, with no hands-on, dry-sack handling.

Cost savings have been shown in: reducing idle rig time (by more effectively meeting lost circulation challenges), better-performing drilling fluids (through more thorough mixing technology), reduction of waste-to-shore materials (eliminating paper sacks, wooden pallets and shrink-wrap), and improved worker health and safety.

Operators have recognized that buying mud products in bulk presents a large benefit in cost reduction. The Bulk Mixer System incorporates the efficient handling of bulk materials transported to the rigs in one-ton bulk bags. Another patent by the developer deals with protective, space-saving baskets designed to protect bulk bags during transfer from shore to rigs.