Patent ID: 6979116

Claim:
An apparatus for introducing dry powderous material into an external fluid stream to maintain a predetermined mixture level in said stream comprising: a. a vertically oriented silo for storing said dry material in bulk form, said silo having an inlet and an outlet for, respectively, receiving and discharging said material; b. a surge hopper located gravitationally downstream from the storage silo, said hopper being separated from the silo by a control valve; c. a volumetric feeder located gravitationally downstream from the hopper, said feeder including a horizontally oriented metering auger coupled with an intromitter for conditioning and feeding said dry material; d. a processor controlled variable speed motor for driving said metering auger and said intromitter for precise metering of said dry material; e. a mixing tank for receiving the dry material from said feeder and mixing it with a fluid to form a slurry, said tank including at least one mixer; f. a pump for removing slurry from said tank through an outlet and introducing it into said external fluid stream through an injection line connected between said pump and said external fluid stream; g. an inlet in said tank in communication with a source of fluid, and a float valve adjacent to said tank inlet for maintaining a desired level of slurry in said tank; and h. and a processor in communication with said motor and with at least one sensor in said external fluid stream, wherein said processor varies the speed of said motor to vary the quantity of dry material metered into said tank in accordance with readings from said at least one sensor so as to introduce slurry from said tank containing variable quantities of said material to maintain a desired volume of said material in said external fluid stream.