Borosilicate glass plant

By virtue of its chemical and thermal resistances, borosilicate glass has superior resistance to thermal stresses and shocks, and is used in the manufacture of a variety of items for process plants. Examples are pipe up to 60 cm in diameter and 300 cm long with wall tliicknesses of 2-10 mm, pipe fittings, valves, distillation column sections, spherical and cylindrical vessels up 400-liter capacity, centrifugal pumps with capacities up to 20,000 liters/hr, tubular heat exchangers with heat transfer areas up to 8 m, maximum working pressure up to 275 kN/m, and heat transfer coefficients of 270 kcal/hz/m C [48,49]. 

Borosilicate glass (known by several trade names, including Pyrex) is used for chemical plant as it is stronger than the soda glass used for general purposes it is more resistant to thermal shock and chemical attack. 

Evolution did not use this element, only in certain plants is it important as a trace element. The element became well-known because of heat-resistant borosilicate glasses. Boranes are chemically interesting as B-H bonds react very specifically. Perborates are used in laundry detergents (Persil). The hardness of cubic boron nitride approaches that of diamond. Amorphous (brown) boron burns very quickly and gives off much heat and is therefore used in solid-propellant rockets and in igniters in airbags. 

AVM [Atelier de Vitrification de Marcoule] A continuous process for immobilizing radioactive waste by incorporation in a borosilicate glass. Developed at Marcoule, France, in 1972, based on the earlier PIVER process. In 1988, two larger vitrification plants were... 

ESTER A batch process for immobilizing nuclear waste in a borosilicate glass for longterm disposal. Developed in Italy in the 1970s and installed at the Euratom Research Centre, Ispra, in 1981. Intended for use in the radioactive pilot plant (Tmpianto Vetrificatione Eurex, IVEX) at the European Extraction Plant (UREX) at Saluggia, Italy. 

WIP [Waste Immobilization Plant] A process for immobilizing nuclear waste by incorporation in a borosilicate glass for long-term disposal. Developed in the 1970s in India for use at the waste immobilization plant at Tarapur. 

Plant samples were dried, ground and then redried for four hours at 90 °C before analysis. The dried sample (1 g) was placed in a borosilicate glass tube and digested with 1 ml of a mixed digestion acid (200 ml 72% m/v perchloric acid and 50 ml 68% m/v nitric acid) plus 5 ml redistilled 72% m/v nitric acid and two drops of kerosene to prevent frothing. The tubes were digested for three hours at 130 °C, and then 2 ml of redistilled 20% m/v hydrochloric acid is added when cold. After treatment with sodium borohydride, the solutions are evaluated at the selenium 196 nm resonance line. 

Characterization of Borosilicate Glass-Containing Savannah River Plant Radioactive Waste... 

An environmental assessment 1) concluding that borosilicate glass is suitable for the immobilization of Savannah River Plant (SRP) waste has recently been published by the Department of Energy. 

High-level radioactive waste (HLW) will be converted from an alkaline slurry to a durable borosilicate glass in the Defense Waste Processing Facility (DWPF) at the Savannah River Plant (SRP) in South Carolina [17]. This waste is the residue from thirty years of reprocessing of irradiated nuclear fuels for national defense purposes and is currently stored in large carbon-steel tanks. 

This paper reviews the Rocky Flats Plant e q)erience in the application of borosilicate-glass Raschig rings as a primary criticality control in fissile-solution handling processes. Included is a history of their introduction at Rocky Flats as well as a record of the problems encountered with their use. 

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