The Consolidated Incineration Facility at the Savannah River Site is designed without emergency flue gas vents. The main components of this 18 million btu/hr facility are a rotary kiln and secondary combustion chamber, each with a code allowable internal pressure of 15 psig. The facility is designed to treat mixed waste. During the early stages of design it was judged on a qualitative basis that potential eventsthat might produce damaging overpressures were not credible. When these findings were questioned during subsequent design reviews, a probabilistic risk assessment was undertaken to provide a quantitative basis for decision making. The result was identification of design conditions leading to relatively high frequencies for a few event sequences in which the allowable pressure might be exceeded. Risk assessment assumptions and results were reviewed with design engineers and relatively simple improvements were identified that collectively reduced the frequency of overpressure to an acceptable level. This experience showed that the use of formalized risk assessment techniques can provide valuable insight leading to timely and cost-effective improvements in facility design and operating procedures. In this case, the program of analysis and follow-on improvements provided justification for incinerator operation without thermal relief devices.

The Consolidated Incineration Facility at the Savannah River Site is designed without emergency flue gas vents. The main components of this 18 million btu/hr facility are a rotary kiln and secondary combustion chamber, each with a code allowable internal pressure of 15 psig. The facility is designed to treat mixed waste. During the early stages of design it was judged on a qualitative basis that potential eventsthat might produce damaging overpressures were not credible. When these findings were questioned during subsequent design reviews, a probabilistic risk assessment was undertaken to provide a quantitative basis for decision making. The result was identification of design conditions leading to relatively high frequencies for a few event sequences in which the allowable pressure might be exceeded. Risk assessment assumptions and results were reviewed with design engineers and relatively simple improvements were identified that collectively reduced the frequency of overpressure to an acceptable level. This experience showed that the use of formalized risk assessment techniques can provide valuable insight leading to timely and cost-effective improvements in facility design and operating procedures. In this case, the program of analysis and follow-on improvements provided justification for incinerator operation without thermal relief devices.

The pressures in baked an unbaked experimental beam-pipes are calculated as a function of time. These results exclude gas impact desorption effects stemming from, for example, species created by the colliding beams. Three general cases have been calculated: Case {number_sign}1: an unbaked system cryopumped by the 4.2{degree}K apertures of the DO magnets; Case {number_sign}4: an unbaked system pumped by the 4.2{degree}K apertures of the DO magnets, and with a 10,000 L/sec LHe cryopump located proximate to the DX magnets in the DX to D0 beam pipes; Case {number_sign}6: baked beam pipes pumped by the 4.2{degree}K apertures of the D0 magnets and sputter-ion pumps (i.e., SIPs), with non-evaporable getters (i.e., NEGs), bracketing the experimental beam-pipes. The infinite combinations of non-simultaneous system pumpdowns have been excluded as they are impossible to enforce or predict in the heat of operation.

The pressures in baked an unbaked experimental beam-pipes are calculated as a function of time. These results exclude gas impact desorption effects stemming from, for example, species created by the colliding beams. Three general cases have been calculated: Case [number sign]1: an unbaked system cryopumped by the 4.2[degree]K apertures of the DO magnets; Case [number sign]4: an unbaked system pumped by the 4.2[degree]K apertures of the DO magnets, and with a 10,000 L/sec LHe cryopump located proximate to the DX magnets in the DX to D0 beam pipes; Case [number sign]6: baked beam pipes pumped by the 4.2[degree]K apertures of the D0 magnets and sputter-ion pumps (i.e., SIPs), with non-evaporable getters (i.e., NEGs), bracketing the experimental beam-pipes. The infinite combinations of non-simultaneous system pumpdowns have been excluded as they are impossible to enforce or predict in the heat of operation.