Apparatus for slurrying powdered solids

An apparatus for introducing powdered solids into a liquid stream at a controlled rate to form a slurry, comprising:

• a vessel for storing powdered solids and from which solids flow is assisted by gravity;
• metering means communicating with said storage vessel and controlling the flow rate of said solids from said vessel;
• an eductor through which said liquid stream passes, having a pressure liquid inlet, suction inlet for introduction of said solids into the liquid, and outlet for discharging the slurry formed thereby;
• a conduit for transporting said solids from said metering means to said eductor;
• a first power actuated valve in said conduit;
• a pressure liquid line connected to pressure liquid inlet of eductor;
• a second power actuated valve in said pressure liquid line;
• a first pressure sensor in said pressure liquid line;
• a slurry discharge line from eductor outlet to a slurry using process;
• a second pressure sensor in said slurry discharge line;
• automatic cycle timer-controller means sequentially opening said second power actuated valve for a first predetermined time period, subsequently opening said first power actuated valve and activating said metering means, maintaining both said power actuated valves open and said metering means activated for a first controlled time period, subsequently closing first power actuated valve and deactivating said metering means for a second predetermined time period, subsequently closing said second power actuated valve, maintaining both power actuated valves closed and metering means deactivated for a second controlled time period, and thereafter, repeating automatic timer-controller sequence;
• and
• automatic means for closing both power actuated valves and deactivating said metering means when said first pressure sensor measures pressure lower than a first preset value or when said second pressure sensor measures pressure higher than a second preset valve or when the measured pressure difference between the first and second pressure sensors is less than a third preset value.