Compressor(s) in air distillation unit supplies gas(es) to industrial unit which produces steam and are driven using steam from industrial unit and auxiliary source

摘要

The means of expanding the steam has two inlets for different inlet pressures (high and medium), and during at least one phase of operation of the industrial unit, the means of expansion is at least partially supplied by an auxiliary steam supply from an auxiliary source (21) introduced at the other inlet in the means of expansion. Process for driving at least one compressor (7, 8) in an air distillation unit (3), which supplies oxygen and/or nitrogen and/or argon to an industrial unit (1) producing steam, in which the compressor is driven at least partly by means (13) of expanding the steam with production of external work, fed by the steam from the industrial unit. This steam is introduced at an inlet (15, 16) to the means of expansion. The auxiliary source is used during start-up, and in established operation, the majority of the steam is supplied by the industrial unit. The high pressure inlet is permanently supplied and the auxiliary steam is at the medium pressure. The auxiliary steam is sent to both inlets, then the steam from the industrial unit is supplied to the high pressure inlet while the auxiliary steam supplies the medium pressure inlet, and then the industrial unit supplies at least the high pressure inlet. Alternatively, the auxiliary steam is at the high pressure and the industrial unit supplies medium pressure steam, so auxiliary steam is sent to both inlets, then the steam from the industrial unit is supplied to the medium pressure inlet while the auxiliary steam supplies the high pressure inlet and then the industrial unit supplies both inlets. Two compressors are driven using the same axle, with a principal air compressor (7) and another gas compressor (8), in particular an air suppressor for the air distillation unit. The means of expansion comprises a steam turbine with two inlets. An Independent claim is included for an installation for carrying out the above process.