Process and apparatus for scrubbing a gas stream
AssigneeL'Air Liquide, Societe Anonyme pour I'Etude et I'Exploitation des Procedes Georges Claude
InventorsGian Luigi CALORO, Martin Raventos, Francois Fuentes
Life of this patent
Estimating the term…
Abstract
In a process for the scrubbing of a gas stream, liquid (7) from the scrubbing tower (K) is vaporized (E1) in order to cool ambient air (19) which is subsequently used to cool water (25), producing cooling water (27) to be used upstream or downstream of the scrubbing process.
Claims14
A process for scrubbing a gas stream, in which:
- i) a gas stream comprising at least one NOx and/or at least one SOx and/or suspended matter and at least 15 mol % of CO2 on a dry basis is sent to a scrubbing tower where it is cooled and scrubbed with water and/or with an alkaline liquid in order to produce a gas enriched in CO2 at the top of the tower and a bottom liquid enriched in the at least one NOx and/or the at least one SOx and/or suspended matter at the bottom of the tower,
- ii) at least a part of the bottom liquid is filtered and/or demineralized in order to produce a purified liquid,
- iii) at least a part of the bottom liquid of stage i) or the purified liquid of stage ii), if present, is used to cool an air flow by evaporation in direct contact or by indirect heat exchange, forming a cooled air flow, and
- iv) the cooled air flow is used to cool a water flow by indirect or direct heat exchange, forming a cooled water flow.
An apparatus for scrubbing a gas stream comprising a scrubbing tower, a treatment unit, a storage facility, an evaporator, a heat-exchange means, a means for sending a gas stream comprising at least one NOx and/or at least one SOx and/or suspended matter and at least 15 mol % of CO2 on a dry basis to the scrubbing tower in order to cool it and to scrub it by means of water and/or of an alkaline liquid in order to produce a gas enriched in CO2 at the top of the tower and a bottom liquid enriched in the at least one NOx and/or the at least one SOx and/or suspended matter at the bottom of the tower, a means for exiting the bottom liquid from the tower, a means for sending at least a part of the bottom liquid to the evaporator in order to be evaporated by direct or indirect heat exchange with an air flow, after having treated the at least a part of the bottom liquid in the treatment unit in order to purify it and/or after having stored the at least a part of the bottom liquid in the storage facility, a means for sending the air flow cooled in the evaporator to the heat-exchange means for indirect or direct heat exchange with a water flow to be cooled, forming a cooled water flow.
Dependencies are inferred from the claim text.