Abstract: A process is provided for treating a water to reduce its hardness by performing a series of sequential stages including a primary chemical reaction stage, a secondary chemical reaction stage and a scale removal stage. The primary chemical reaction stage includes the steps of adding a first hydroxide ion donor in the form of lime to an initial water having an initial hardness and reacting the first hydroxide ion donor to form a first portion of a scale and an intermediate water having an intermediate hardness substantially less than the initial hardness. The secondary chemical reaction stage includes the steps of adding a second hydroxide ion donor in the form of caustic to the intermediate water and reacting the second hydroxide ion donor to form a second portion of the scale and a product water having a product hardness substantially less than the intermediate hardness.

Abstract: A multi-stage process is provided for treating a water to reduce its hardness. The feed water is initially heated to a thermal reaction temperature in a heating stage. The heated water is then maintained at or near the thermal reaction temperature for a sufficient residence time to thermally react the water, producing a first portion of a scale from the scale-forming ions in the water while discharging dissolved gases from the water. After the thermal reaction stage, one or more chemical additives in the form of a hydroxide ion donor and optionally a bicarbonate ion donor are added to the heated water in a chemical reaction stage. The chemical additive is chemically reacted with the water in the chemical reaction stage, producing a second portion of the scale from the scale-forming ions in the water.

Abstract: A means for taking pressure readings in a bottom-hole zone of a well without interfering with an operation in which solid material is moving through a tubing string. A pressure recorder is enclosed in a carrier attached to the outer surface of a tubing sub near the end of the tubing string. The carrier walls include ports which expose the pressure recorder to the fluid in the bottom-hole zone. This arrangement allows operations such as sand fracture stimulations and rod pumping to be unimpeded by a pressure recorder.