Abstract: An optoelectric detector having transparent tubes separated by a thin opaque barrier with LEDs in one tube adjacent one side of the barrier and a photoconductor in the other tube adjacent to the opposite side of the barrier. The LEDs and photoconductor being in close proximity with the photoconductor with the photoconductor only receiving light emitted by the LEDs which is reflected from the solids in medium in which the detector is used.

Abstract: A control system having optoelectric detectors responsive to different solids concentrations and character of the solids of a slurry, the signal of the detectors being input to a process controller which adjusts the rate of addition of chemicals to the feed stream of a froth cell to control the separation of solids from impurities. The impurities pass out of the cell as tailings. The controller calculates a feedforward output from the signals from detectors sensing different slurry conditions in the process feed stream, and the controller output adjusts the addition of different chemicals (additives) to the processing cell. The controller also calculates a feedback output after receiving a signal from a third detector in the tailings which monitors the extent of separation and recovery of solids from the processing cell.

Abstract: A control system having opto-electric detectors responsive to different solids concentrations and character of the solids of a slurry, the output of the detectors controlling the addition of a flocculants to the slurry to optimize coagulation of the materials in the slurry. The detectors having outputs sensing different slurry conditions with the detector outputs being processed to control the addition of different flocculants to the cell.

Abstract: A control system having opto-electric detectors responsive to different solids concentrations and character of the solids of a slurry, the output of the detectors controlling the addition of a flocculants to the slurry to optimize coagulation of the materials in the slurry. The detectors having outputs sensing different slurry conditions with the detector outputs being processed to control the addition of different flocculants to the cell.