Selective hydrocracking of total coolant was found to be an efficient and economic method for reconstitution of high boiler in the coolant to usable product. Such a process could eliminate the expense of vacuum distillation and disposal of high boilers produced in a nuclear reactor power plant. The selective conversion was possible since polyphenyls were found to be more susceptible towards hydrocracking as the phenyl chain length increased. Both cobalt molybdate on alumina and nickel oxide on alumina (50 to 80 square meters per gram) were found to be efficient catalysts at conditions of 900 deg F and 1000 psig with the latter giving more selective conversion to terphenyls. Continuous flow hydrocracking tests on OMRE Core II cool ant (containing 23% high boiler) resulted in 90 to 100% conversion of high boiler at product recoveries of 85 to 95 wt%. Average molecular weights of the products (biphenyl and heavier) were in the range 205 to 225 compared to 270 for Core II coolant. High boiler in Core III-A coolant which contained mainly first-generation polymers (hexaphenyls) was slightly more refractory toward hydrocracking than Core II high boiler, and conversion decreased slightly with increasing on-stream time. However, at optimum condition for processing …

The detailed description includes flow measuring methods, flow rate calculations, operating pressure constants, crossheader number, header elevation corrections, and header pressures for the reactor record. The unit records include: tube number, header number, flow zone, trip dial readings, effective range, taps, corrosion index, rib type, rear fitting type, Panellit pressure, date, calculation methods, tube flow rate, tube class, load type, charge date, and header pressures. The reactor operating limits include: tube number and class, tube flow rate, Panellit pressure, boiling limits, base pressure, adjustment date, limit codes, load type, and flow factors.

Reduction of the reactor process water pH from 6.9 to 6.6 at 100-B, D, DR, KF, and H currently is proposed in order to reduce the aluminum corrosion rate and the resultant outage time for water leaks, fuel ruptures, and process tube replacement. This document reviews the current knowledge of the effect of reducing the pH to 6.6 on aluminum corrosion. An estimate of the expected costs and benefits is included.

Studies were initiated at Hanford in 1961 and 1962 toward the development of an alternate assembly process for the production of I&E fuel elements for the eight existing Hanford reactors. Of the processes considered, hot die sizing, a diffusion bonding process, offered the greatest incentives in terms of improved quality and potentially cheaper unit cost of fuel elements compared to the currently used AlSi braze process. This interim report presents the results of initial process variables tests designed to establish optimum process parameters for producing good diffusion bonds on the lateral external and internal surfaces of I&E fuel elements during the sizing step of the hot die size process. In a subsequent step, the end bonds are formed. Optimization studies for producing good end bonds will be reported in future interim reports.

This report is applicable to the eight operating production reactors, B, C, D, DR, F, H, KE, and KW. It covers the following: operating parameter limitations; reactivity limitations; control and safety systems; reactor fuel loading; coolant requirements with irradiated fuel in reactor; reactor confinement; test facilities; code compliance; safety instrumentation and set points; and control criteria. Also discussed are administrative procedures for process control, training, audits and inspection, and reports and records.

Hot die sizing is one of three solid state diffusion bonding (SSDB) processes that has been proposed as an alternate manufacturing process for fabricating HAPO metallic uranium, aluminum-clad fuel elements. This document establishes the provisional process specifications for the assembly of fuel elements by the hot die sizing process. These specifications were developed for the CDB2N model fuel element (CSN equivalent AlSi model) and do not necessarily apply to any other model.

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Additional data from the 3.2-msec-period destructive test were analyzed. Recovery and cleanup operations in the Spert I area were completed. Each of the 270 highly enriched, aluminum-clad fuel plates in the core was found to have experienced melting to some degree. The available data on the nature of the pressure pulse and on the condition of the core fuel plates at the time of the pulse are consistent with the hypothesis that the observed destructive effects were produced by a self-propagating steam explosion resulting from the dispersal of molten fuel plates into the water throughout the core. A series of tests was initiated to determine the response of the Spert IV plate-type core to step- inputs of reactivity at ambient temperature, for various initial system conditions of hydrostatic head above the core, and forced coolant circulation rate. Power excursion tests with initial reactor periods in the range from 1 sec to 8.5 msec were performed with an 18-ft hydrostatic head above the core and no forced coolant circulation. Tests with periods of 20, 12, and 8.5 msec were also performed with a 2-ft head. No significant change was observed in the peak power, power burst shape, energy release, or transient …