Dryer temperature control
AssigneePhillips Petroleum Company
InventorRobert J. Perry
Life of this patent
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Abstract
A slurry of particulate material, such as polypropylene, and a fluid, such as propylene diluent, is introduced into a flash tank to remove a substantial amount of the fluid. The resulting particulate material is passed from the flash tank through a heated dryer to elevate the temperature of the particulate material and remove additional fluid. The temperature of the particulate material removed from the dryer is controlled by measuring the temperature of the removed material and adjusting the rate at which vapor is removed from the dryer in response to the measured temperature.
Claims10
A method of drying particulate material to remove volatile fluid therefrom comprising passing the material through a heated dryer, venting vaporized fluid from the dryer, measuring the temperature of the particulate material removed from the dryer, and controlling the rate at which the fluid is vented so as to maintain the measured temperature at a preselected value, said fluid being vented at an increased rate when the measured temperature falls below a preselected value and being vented at a decreased rate when the measured temperature rises above the preselected value.
Apparatus for drying particulate material comprising a dryer having an inlet and an outlet, conduit means communicating with said dryer to remove gases evolved from the particulate material, a valve in said conduit means, temperature sensing means positioned to measure the temperature of particulate material removed from the dryer, and control means responsive to said temperature sensing means to regulate the flow of gases through said conduit means, said control means moving said valve toward an open position when the measured temperature falls below a preselected value and moving said valve toward a closed position when the measured temperature rises above the preselected value.
Dependencies are inferred from the claim text.