Online analytical systems for the uranium solidification facility at SRS

A new Uranium Solidification Facility (USF) is scheduled for completion in the latter part of 1990. This facility will convert liquid uranyl nitrate product from the Savannah River Site reactor reprocessing plant to solid uranium trioxide for shipment to Oak Ridge Y-12 plant. High- and low-level online uranium measurement systems have been developed to provide nuclear safety, process control, material control, and accountability information to the facility operator. The low level uranium concentration will be determined by an improved online alpha monitoring system for aqueous streams developed at the Savannah River Site. High uranium concentrations will be measured by a fiber-optic-based diode array absorption spectrophotometer. The online alpha monitor (OLAM-100S) consists of a 5-in. circular sample chamber and an alpha particle detector (a thin film of polyvinyl toluene plastic scintillation material) attached to a light guide and processing electronics. The light guide is optically coupled to a photomultiplier tube. Processing electronics include: amplifier/single channel analyzer, a dual counter/timer, and a high and low level alarm module. In order to implement the system online, a cell drain, automatic flushing mechanism, heat exchanger, temperature readout, and flow monitor will be used. The absorption spectrophotometer system consists of a xenon arc lamp, a nine-position fiber optic multiplexer (to allow a single system to monitor up to nine process locations), automated process samplers, diode array spectrometer, and a central computer system. 5 refs., 10 figs., 1 tab