Solute gas-absorbing procedure

A method for the removal of a solute gas, which is an acid gas selected from the group consisting of SO.sub.2, H.sub.2 S, Cl.sub.2, ClO.sub.2, NO.sub.x, HCl, HF, SO.sub.2, CO.sub.2 and mixtures thereof, from a gas stream containing the same using an absorbing medium for said solute gas, which is a regenerable alkaline aqueous medium, which comprises:

• passing said gas stream through an elongate conduit having an inlet thereto and an outlet therefrom;
• feeding said absorbing medium in parallel to at least two dual-fluid spray nozzles located in longitudinally spaced-apart relationship in said conduit;
• injecting said parallel-fed absorbing medium from each of said spray nozzles by atomizing gas to form a spray pattern of said absorbing medium in said conduit from each nozzle and containing liquid droplets ranging in size from about 5 to about 150 microns;
• absorbing solute gas from said gas stream into said liquid droplets of absorbing medium in each said spray pattern in said conduit;
• and
• agglomerating said liquid droplets containing absorbed solute gas at said outlet of said conduit to remove entrained liquid droplets from said gas stream and form a liquid stream containing absorbed solute gas.

A method for the removal of a solute gas, which is SO.sub.2, from a gas stream containing the same, which is substantially saturated with water vapor, using an absorbing medium for said solute gas, which is a regenerable aqueous solvent, which is an aqueous solution of an amine, diamine or monosalt of a diamine in which the SO.sub.2 may be dissolved and from which the SO.sub.2 may be subsequently desorbed, which comprises:

• passing said gas stream through an elongate conduit having an inlet thereto and an outlet therefrom;
• feeding said absorbing medium in parallel to at least two dual-fluid spray nozzles located in longitudinally spaced-apart relationship in said conduit;
• injecting said parallel-fed absorbing medium from each of said spray nozzles by atomizing gas to form a spray pattern of said absorbing medium in said conduit from each nozzle and containing liquid droplets ranging in size from about 5 to about 150 microns;
• absorbing solute gas from said gas stream into said liquid droplets of said absorbing medium in each said spray pattern in said conduit;
• and
• agglomerating said liquid droplets containing absorbed solute gas at said outlet of said conduit to remove entrained liquid droplets from said gas stream and form a liquid stream containing absorbed solute gas.

A method for the removal of a solute gas comprising cl.sub.2 and ClO.sub.2 contained in a pulp mill bleach plant emission stream using an absorbing medium for said solute gas, which is selected from pulp mill E filtrate, weak wash, white liquor and mixtures thereof, which comprises:

• passing said gas stream through an elongate conduit having an inlet thereto and an outlet therefrom;
• feeding said absorbing medium in parallel to at least two dual-fluid Spray nozzles located in longitudinally spaced-apart relationship in said conduit;
• injecting said parallel-fed absorbing medium from each of said spray nozzles by atomizing gas to form a spray pattern of said absorbing medium in said conduit from each nozzle and containing liquid droplets ranging in size from about 5 to about 150 microns;
• absorbing solute gas from said gas stream into said liquid droplets of absorbing medium in each said spray pattern in said conduit;
• and
• agglomerating said liquid droplets containing absorbed solute gas at said outlet of said conduit to remove entrained liquid droplets from said gas stream and form a liquid stream containing absorbed solute gas.

A method for the removal of a solute gas, which is selected from H.sub.2 S, CO.sub.2 and mixtures thereof, from a gas stream containing the same using an absorbing medium for said solute gas which is a regenerable aqueous alkanolamine solution, which comprises:

• passing said gas stream through an elongate conduit having an inlet thereto and an outlet therefrom;
• feeding said absorbing medium in parallel to at least two dual-fluid spray nozzle located in longitudinally spaced-apart relationship in said conduit;
• injecting said parallel-fed absorbing medium from each of said spray nozzles by atomizing as to form a spray pattern of said absorbing medium in said conduit from each pattern of containing liquid droplets ranging in size from about 5 to about 150 microns;
• absorbing solute from said gas stream into said liquid droplets of absorbing medium in each said spray pattern in said conduit;
• and
• agglomerating said liquid droplets containing absorbed solute gas at said outlet of said conduit to remove entrained liquid droplets from said gas stream and form a liquid stream containing absorbed solute gas.

A method for the removal of a solute gas, which is SO.sub.2, from a gas stream containing the same, which is substantially saturated with water vapor, using an absorbing medium for said solute gas, which comprises an aqueous solution of an amine, diamine or monosalt of a diamine in which the SO.sub.2 may be dissolved and from which the SO.sub.2 may subsequently be desorbed, which comprises:

• passing said gas stream through an elongate conduit having an inlet thereto and an outlet therefrom;
• feeding said absorbing medium in parallel to a first at least two dual-fluid spray nozzles located in longitudinally spaced-apart relationship in a downstream solute gas-absorbing zone in said conduit;
• injecting said parallel-fed absorbing medium from each of spray nozzles by atomizing gas to form a spray pattern of said absorbing medium in said downstream solute gas-absorbing zone from each nozzle and containing liquid droplets ranging in size from about 5 to about 150 microns;
• absorbing solute gas from said gas stream into said liquid droplets in each said spray pattern in said downstream solute gas-absorbing zone;
• agglomerating said liquid droplets contain absorbed solute gas at said output of said conduit to remove entrained liquid droplets from said gas stream and form a partially-loaded absorbing means;
• feeding said partially-loaded absorbing medium in parallel to a second at least two dual-fluid spray nozzles located in longitudinally spaced-apart relationship in an upstream solute gas-absorbing zone in said conduit;
• injecting said parallel-fed partially-loaded absorbing medium from which said spray nozzle in said second at least two spray nozzles to form a spray pattern from each nozzle of said partially-loaded absorbing medium in said upstream solute gas-absorbing zone in said conduit and containing liquid droplets ranging in size from about 5 to about 150 microns;
• absorbing solute gas from said gas stream into said liquid droplets of partially-laden absorbing medium in each said spray pattern in said upstream gas-absorbing zone;
• and
• agglomerating said liquid droplets of partially-laden absorbing medium at the downstream end of said upstream gas-absorbing zone to remove entrained liquid droplets from said gas stream exiting said upstream gas-absorbing zone and form a fully-loaded absorbing medium.