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An electrical submersible well pump installation has a downhole secondary pump for pumping scale inhibiting chemicals below the downhole pumping assembly. The downhole pumping assembly includes a centrifugal primary pump driven by an electrical motor located below the pump and separated by a seal se

An electrical submersible well pump installation has a downhole secondary pump for pumping scale inhibiting chemicals below the downhole pumping assembly. The downhole pumping assembly includes a centrifugal primary pump driven by an electrical motor located below the pump and separated by a seal section for preventing well fluids from entering the motor. The secondary pump is also driven by the motor and is located between the seal section and the primary pump. The secondary pump has an intake connected to a tube that extends upwardly above the intake of the primary pump. The secondary pump has a discharge port connected to a discharge tube that extends downwardly to a point below the motor. Chemicals introduced at the surface into the annulus flow downwardly into the intake of the secondary pump and are discharged below the motor. The secondary pump has an inverted impeller and diffuser that have a discharge on the lower end for discharging fluids downwardly.

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In a well installation having a casing, a string of tubing extending to a downhole centrifugal pumping assembly, defining an annulus between the casing and the tubing and pumping assembly, and means at the surface for introducing inhibiting chemicals into the annulus, the pumping assembly including

In a well installation having a casing, a string of tubing extending to a downhole centrifugal pumping assembly, defining an annulus between the casing and the tubing and pumping assembly, and means at the surface for introducing inhibiting chemicals into the annulus, the pumping assembly including a centrifugal primary pump which has an intake on its lower end and is driven by an electrical motor located below the pump, the improvement being a centrifugal secondary pump adapted to be connected to the pumping assembly, comprising in combination: a tubular housing having an intake port on its upper end adapted to be connected to an intake tube that extends upwardly in the annulus to a point above the intake of the primary pump, and a discharge port on its lower end; a shaft rotatably mounted in the housing and adapted to be driven by the motor; and an impeller and diffuser assembly mounted in the housing, having an intake facing upwardly in the housing and a discharge located below the intake of the impeller and diffuser assembly and facing downwardly in the housing, for pumping inhibiting chemicals drawn from the annulus downwardly into the well, to be then drawn upwardly into the intake of the primary pump.