Abstract: The subject matter of the invention is dextrans which have between 95% and 99% of ?-1,6 glucosidic bonds, a weight-average molar mass Mw at least equal to 0.7×109 g.mol?1, and a dispersity index D of between 1.3 and 3. The invention also relates to a dextran saccharase which makes it possible to produce such dextrans, and to a method for producing said dextrans.

Abstract: The subject matter of the invention is dextrans which have between 95% and 99% of ?-1,6 glucosidic bonds, a weight-average molar mass Mw at least equal to 0.7×109 g.mol?1, and a dispersity index D of between 1.3 and 3. The invention also relates to a dextran saccharase which makes it possible to produce such dextrans, and to a method for producing said dextrans.

Abstract: Process and installation for the production of gaseous oxygen and/or gaseous nitrogen under pressure, of the type in which air is distilled in a double distillation column (11) comprising a low pressure column (13) operating under a so-called low pressure, and a medium pressure column (12) operating under a so-called medium pressure. All the air to be distilled is compressed (in 1, 3, 7)to at least one high air pressure substantially greater than the medium pressure, and the compressed air is cooled to an intermediate temperature, and a portion of it is expanded in a turbine (8) to the medium pressure, before introducing it into the medium pressure column (12). The air which has not been expanded is liquefied, then introduced after expansion (in 20, 21), into the double column. At least one liquid product withdrawn from the double column is brought to the production pressure, and this liquid product is vaporized by heat exchange with at least one portion of the air to be distilled in the course of cooling.

Abstract: A process for simultaneously providing both high and low purity oxygen from a double column, double reboiler apparatus, the double columns being high and low pressure columns, the low pressure column having a lower and upper reboiler with an intermediate outlet in between, which process entails extracting a low purity oxygen stream at the intermediate outlet and a high purity liquid oxygen stream from a bottom portion of the low pressure column.

Abstract: In this process of the liquid nitrogen/rich liquid HPN swing type, the connection between the head of the column (4) and the liquid nitrogen holding tank (7) is effected, for the two flow directions of the liquid nitrogen, by a single conduit (12) equipped with a pressure reducing device (13). The direction and the flow rate of the liquid nitrogen flow are controlled by the variations of the pressure of the column, and the holding tanks of liquid nitrogen and rich liquid are maintained at constant pressures.

Abstract: An apparatus for simultaneously producing both high and low purity oxygen, which contains a double rectification column having therein a lower pressure fractionating column with two reboilers therein, and a higher pressure fractionating column, wherein an intermediate outlet is provided between the two reboilers of the lower pressure fractionating column for extracting a lower purity oxygen stream therefrom, and a high purity liquid oxygen stream from a bottom portion of the column simultaneously.

Abstract: A column for production of nitrogen by the distillation of air, adapted to produce high purity nitrogen at its head, is associated with an external source of medium purity liquid nitrogen that is fitted with a device for the liquid phase adsorption of carbon monoxide, and with a reservoir for the storage of high purity liquid nitrogen. The column produces medium purity gaseous nitrogen and high purity gaseous nitrogen by direct withdrawals, optionally supplemented by vaporization of liquid nitrogen.

Abstract: A process for simultaneously providing both high and low purity oxygen from a double column, double reboiler apparatus, the double columns being high and low pressure columns, the low pressure column having a lower and upper reboiler with an intermediate outlet in between, which process entails extracting a low purity oxygen stream at the intermediate outlet and a high purity liquid oxygen stream from a bottom portion of the low pressure column.