Abstract: A process control system for use in movement of slurry material from a first lower level through a vertical flow way to an upper or surface level. In particular, this system is utilized for moving slurried particulate from a subterranean mine level upward through a vertical flow way such as an earth borehole to a surface pumping station or the like. The vertical pump system includes series-connected pumps having variable speed capabilities at the lower level, and the pumps then direct the slurried material through the vertical flow way to an upper level receiving station. The process control monitors the upper level volume, the slurry line pressure in the pipeline underground, and the flow rate in the pipeline underground thereby to select a controller output signal. The output signal is then utilized to control a hydraulic servo mechanism which adjusts the variable speed drive to one or more of the series-pumps thereby to maintain a proper flow rate and pressure through the vertical flow way.

Abstract: A method and apparatus for sequence control of vertical movement of slurried particulates from a lower level to the upper levels, more particularly a vertical hoist system for movement of slurry from a subterranean mine area upward through an earthen or cased borehole to a surface station. The vertical pump system includes series-connected pumps having variable speed capability to transport slurry particulate from an underground sump upward to a surface surge tank or other repository. The logic sequence system exercises control over valving sequence between the underground pumps and the vertical borehole in order to control slurry surges during start-up, shut-down and emergency dump operations. Thus, the pump input to the vertical conduit utilizes energy dissipator units as selectively controlled by automated block and by-pass valves to control flow of fluids from the pumps upward through the vertical conduit.