Multiple tub mobile blender

A dual tub blending apparatus for use in well servicing operations, said blending apparatus comprising:

• a) a pair of blending tubs, each of said tubs having a particulate matter inlet means, a fluid inlet means, a slurry outlet means, and a mixing means, the particulate matter inlet means including a distribution bin for storing the particulate matter and feeding the particulate matter to the individual blending tubs as needed, said bin being filled by a loading means which maintains an adequate supply of particulate matter in said bin;
• b) said fluid inlet means on each tub being connected by pipe sections having approximately the same length to an inlet manifold pipe which is connected to a source of fracturing fluid which is used in the well servicing operations;
• c) said slurry outlet means including a pair of individual pipe sections having approximately the same length connected to a slurry discharge manifold pipe for combining the discharges from the pair of blending tubs, balancing the outlet pressures of said blending tubs and delivering a slurry of fracturing fluid and particulate matter from said blending tubs at a constant outlet pressure to said discharge manifold pipe;
• d) said blending tubs each having an impeller which rotates about a vertical axis and is suspended from above leaving an open plenum space below said impeller, said slurry outlet means for each tub being attached to the tub in the general area adjacent to said plenum space;
• and
• e) connector means for connecting said slurry discharge manifold pipe to an inlet of a downhole pump apparatus, wherein the slurry constant outlet pressure from the discharge manifold pipe supports and stabilizes the inlet pressure of the downhole pump during well servicing operations.

In a multiple blending tub apparatus for use in well servicing operations, each of said blending tubs comprising:

• a) a cylindrical tub having a side wall, an enclosed bottom and a partially open top;
• b) a particulate matter inlet means provided through said top;
• c) a fluid inlet means positioned in the side wall of said tub;
• d) a slurry outlet means positioned in the side wall and below the fluid inlet means;
• e) said tub having a centrally positioned impeller which rotates about a vertical axis and is suspended from above leaving an open plenum space between said impeller and the bottom of the tub, said impeller being driven by a suitable drive means;
• and
• f) the particulate matter is introduced into the tub through the top of the tub and into the impeller, wherein the particulate matter is mixed with a fluid entering the tub through the fluid inlet means producing a slurry of fluid and particulate matter which descends into the open plenum space and is discharged through the slurry outlet means which is adjacent the plenum space, whereby the outlet flow of the slurry is stabilized and balanced by said open plenum space.