Methods and apparatus for controlling a characteristic of a cement slurry at a cementing unit, including regulating a characteristic of the cement slurry employing a closed loop feedback arrangement in the cementing unit, and adjusting a gain of the closed loop feedback arrangement in response to sampling an error of the characteristic.

A technique facilitates mixing of cement slurry for use in a cementing application. At least one cement mixer is provided with a tank, e.g. a conical tank, having a powder cement blend inlet and a mixing liquid inlet. A cement slurry discharge may be positioned generally beneath the tank. A mixing assembly also is positioned below the tank and driven by a shaft. The mixing assembly is exposed to an interior of the tank and is used to mix the cement slurry when rotated by the shaft and to direct the cement slurry out through the cement slurry discharge. Additionally, a recirculation system comprises an inlet positioned to receive a portion of the cement slurry mixed in the mixing assembly. The recirculation system also comprises an outlet positioned to direct the portion back into the mixer to enhance mixing effects.

An integrated fluids mixing and delivery system includes one or more mixers configured to receive a cement powder and a flow of a mixing liquid, and to mix the cement powder and the flow of the mixing liquid to form a cementing fluid having respective appropriate characteristics for cementing operations. The one or more mixers are also configured to receive a base drilling fluid and a dry component, and to mix the base drilling fluid and the dry component to form a drilling fluid having respective appropriate characteristics for drilling operations.

A mobile aggregate hopper for a volumetric and gravimetric mixer having arcuate longitudinal walls for holding and isolating aggregate. The mobile aggregate hopper has a base integral with the arcuate longitudinal walls with an aggregate transfer conveyor capable of attachment to a trailer or chassis having wheels. The single sheet structure of the longitudinal arcuate side walls minimizes welding and mechanical joints during manufacturing and provides a hopper with high strength and capacity and low overall weight.

Methods of wellbore cementing are provided. A method of analyzing a solid particulate including: measuring a water requirement of the solid particulate; and determining an approximation of specific surface area of the solid particulate from the water requirement.

Methods of wellbore cementing are provided. A method of designing a cement composition may include: selecting a target heat of hydration for a target time and temperature; selecting one or more cementitious components and a weight percent for each of the one or more cementitious components such that a sum of a heat of hydration of the one or more cementitious components is less than or equal to the target heat of hydration; preparing the cement composition; and allowing the cement composition to set.

Embodiments disclosed provide a pump assembly including a first pump for delivering at least one fluid. The first pump may include a first inlet coupled to the first pump for delivering at least one first fluid to the first pump, a second inlet coupled to the first pump for delivering at least one second fluid to the first pump, a first discharge coupled to the first pump for delivering the at least one first fluid at a first pressure, and a second discharge coupled to the first pump for delivering the at least one second fluid at a second pressure. In some embodiments, the first discharge and the second discharge are isolated from each other.

An ingredient blending apparatus is disclosed which blends a plurality of ingredients into a homogeneous blend. The apparatus includes a container which receives various ingredients in a prescribed amount. A vacuum motor has its intake side in communication with the interior of the container to suck the ingredients from the container and blow the same into a blending chamber. The ingredients blown into the blending chamber are mixed and recycled into the vacuum motor and the blending chamber until the ingredients are properly mixed or blended. When the ingredients are properly mixed or blended, they may be sent to an ingredient collection apparatus.

A mixing apparatus having a processing area that exposes free falling dry materials to a high pressure hydration element and forms slurry with the a mixture of the dray materials and liquid.

An apparatus for backfill paste includes a mixing means configured to produce paste, a storage means configured to store paste, and a feeding means configured to feed paste to a borehole. The mixing means and the storing means is formed of a combined storage and mixing means. The feeding means includes a bottom discharge port configured to feed paste from the combined storage and mixing means. The apparatus includes monitoring means configured to monitor the level of paste in the combined storage and mixing means to maintain the level of paste in the combined storage and mixing means above a setpoint value so as to prevent air from entering the borehole from the combined storage and mixing means.