Method and plant for producing an air gas with a variable flow rate
AssigneeL'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
InventorsDarredeau Bernard, Guillard Alain
Life of this patent
Estimating the term…
Abstract
A plant which, when used to produce pressurized oxygen gas, includes a switch, e.g. a liquid oxygen/liquid air switch, for meeting relatively long-term peak demand as well as short-term, high-amplitude peak demand, and a circuit (13,30) for compressing oxygen to a pressure higher than the production pressure. This circuit leads to a buffer (15) at least partially meeting short-term, high-amplitude peak demand.
Claims21
Process for producing a gas from air at a variable flow rate by air distillation in an air distillation unit, in which at least some of the gas to be produced is stored, in the form of a first liquid, in a first storage tank;
- a variable flow of said first liquid is drawn off from said storage tank and brought to gaseous form and to a production pressure, said variable flow being vaporized by condensing a corresponding variable flow of a second fluid;
- said condensed second fluid is stored, in the form of a second liquid, in a second storage tank;
- and a. controlled flow of said second liquid is sent to said. distillation unit, wherein an auxiliary flow of said gas to be produced is brought to gaseous form and to a high pressure greater than said production pressure and then stored in an auxiliary tank under said high pressure, and, during certain peaks in demand of the said gas, at least some of the demanded excess gas is bled off from said auxiliary tank, after having expanded said excess gas to said production pressure.
Plant for producing a gas from air at a variable flow rate, comprising:
- an air distillation unit;
- a heat-exchanger for cooling the air to be distilled by heat exchange with products coming from said distillation unit;
- a first storage tank for storing said gas in the form of a first liquid;
- first means for drawing off a variable flow said first liquid from the first storage tank and bringing of said variable flow to gaseous form and to a production pressure, said first means comprising second means for vaporizing said variable flow by condensing a corresponding variable flow of a second fluid in the form of a second liquid;
- a second storage tank for storing the second liquid;
- third means for bringing an auxiliary flow of the gas to be produced to gaseous form and to a high pressure greater than said production pressure, and then letting said auxiliary flow into an auxiliary tank;
- and a line provided with an expansion and flow-regulating valve and connecting said auxiliary tank to a production line of the plant.
Dependencies are inferred from the claim text.