Method and apparatus for carbon dioxide snow separation

Claim 1

A method of separating carbon dioxide snow from a mixture of carbon dioxide snow and vapor comprising the steps of: expanding a stream of liquid carbon dioxide to a pressure below the thermodynamic triple point into an inlet end of a continuously increasing rectangular cross-section conduit to form a flowing mixture of carbon dioxide snow and vapor; conducting said mixture at sub-atmospheric pressure in a curvilinear path defined by said conduit to subject said flowing mixture to a uniform field of centrifugal forces, whereby said snow is concentrated in a stream in the region having the largest centrifugal force; and separating said concentrated stream of snow from said vapor by a physical barrier to discharge said concentrated stream of snow from said conduit.

Claim 2

A method of separating carbon dioxide snow from a mixture of carbon dioxide snow and vapor comprising the steps of: expanding a stream of liquid carbon dioxide to a pressure below the thermodynamic triple point into an inlet end of a continuously increasing rectangular cross-section conduit to form a flowing mixture of carbon dioxide snow and vapor; conducting said mixture at sub-atmospheric pressure in a curvilinear path defined by said conduit to subject said flowing mixture to a uniform field of centrifugal forces, whereby said snow is concentrated in a stream in the region having the largest centrifugal force; and separating said concentrated stream of snow from said vapor by a physical barrier to discharge said concentrated stream of snow from said conduit.

Claim 5

An apparatus for separting carbon dioxide snow from a mixture of carbon dioxide snow and vapor comprising: a continuously increasing rectangular cross-section conduit having an inlet end, an outlet end, and a discharge orifice adjacent to said outlet end; means in said inlet end for introducing a mixture of carbon dioxide snow and vapor into said conduit thereby causing a flow of the mixture from said inlet end toward said outlet end; said conduit having a curved portion between said inlet end and said discharge orifice shaped so that the two curved walls of said conduit form a flow path for the mixture such that carbon dioxide snow tends to flow in a concentrated stream through said conduit at or near the surface defined by the larger radius, and blade means attached to said conduit at said discharge orifice establishing the size of said discharge orifice and providing physical separation for siad carbon dioxide snow from said vapor.

Claim 6

An apparatus for separting carbon dioxide snow from a mixture of carbon dioxide snow and vapor comprising: a continuously increasing rectangular cross-section conduit having an inlet end, an outlet end, and a discharge orifice adjacent to said outlet end; means in said inlet end for introducing a mixture of carbon dioxide snow and vapor into said conduit thereby causing a flow of the mixture from said inlet end toward said outlet end; said conduit having a curved portion between said inlet end and said discharge orifice shaped so that the two curved walls of said conduit form a flow path for the mixture such that carbon dioxide snow tends to flow in a concentrated stream through said conduit at or near the surface defined by the larger radius, and blade means attached to said conduit at said discharge orifice establishing the size of said discharge orifice and providing physical separation for siad carbon dioxide snow from said vapor.