Porous media to separate gases liquid droplets and/or solid particles from gases or vapors and coalesce entrained droplets

Abstract

Gas-vapor treating and filter mats composed of glass fibers intermixed with micro-bits of any of an expanded thermoplastic styrene-polymer or expanded thermoplastic lower polyolefin or flexible foam polyurethane and a suitable organic bonding agent, which mat may contain any of fibers of a fiber-forming terephthalate polyester, activated carbon, and gas-vapor adsorbent crystalline zeolite molecular sieve particles.

What is claimed is: 
     
       1. A gas-vapor treating mat which comprises (a) glass fibers, of about 6.3 millimeters long and below a length at which they are prone to roping and from about 3 to about 12 microns in diameter, intermixed .[.in the range of from about 4 to about 45 parts.]. with (b) from about 5 to about 50.Iadd.% .Iaddend..[.parts.]. of the micro-bits of .[.any of an expanded, thermoplastic styrene-polymer, an expanded lower polyolefin selected from polyethylene to poly-methylpentene, and.]. and a flexible foamed polyurethane .Iadd.which are in the form of tripodal particles having generally uneven length legs, said particles comprising broken and inter-connected strand portions from adjacent cells of said flexible foamed polyurethane, said strand portions being substantially free of intact cell windows and having hook-like projections, indentations and flutes extending therefrom, said hook-like projections, indentations and flutes having been formed by the destruction of the cell windows of said flexible foam.Iaddend., .[.each said polymer being non-brittle in its initial expanded form;.]. said intermixed glass fibers and polymer micro-bits being held together in sheet or elongated web form and permeable to any of a gaseous and vaporous fluid stream by (c) a binding agent distributed throughout the intermixture of the glass fibers and micro-bits in an amount and manner sufficient to hold them together in the herein noted form and without destroying their permeability, which agent is selected from (i) a compatible organic binder insoluble in cold water and soluble in hot water and inert to the glass fibers, the micro-bits and any other mat constituent as well as to any gas or vapor or entrained droplets or aerosols and fine particles that are to contact the mat and (ii) a cobeat of cotton fibers and any of the micro-bits; whereby the mat has tensile strength from about 0.2 to about 5.3 kilograms per centimeter. 
     
     
       2. A gas-vapor treating mat as claimed in claim .[.1,.]. .Iadd.35 .Iaddend.wherein the micro-bits are those of a styrene-polymer. 
     
     
       3. A gas-vapor treating mat as claimed in claim 2, wherein the micro-bits are of polystyrene. .[.4. A gas-vapor treating mat as claimed in claim 1, 
     
     
        wherein the micro-bits are those of a polyurethane..]. 5. A gas-vapor treating mat as claimed in claim .[.1,.]. .Iadd.35 .Iaddend.wherein the 
     
     
        micro-bits are those of a lower polyolefin. 6. A gas-vapor treating mat as 
     
     
        claimed in claim 5, wherein the polyolefin is polyethylene. 7. A gas-vapor treating mat as claimed in .[.any of claims 1 to 5 or 6.]. .Iadd.claim 1 or 34.Iaddend., wherein the binding agent is polyvinyl alcohol at least 
     
     
        98% hydrolyzed. 8. A gas-vapor treating mat as claimed in .[.any of claims 1 to 5 or 6.]. .Iadd.claim 1 or 34 .Iaddend.wherein the binding agent is a 
     
     
        cobeat of the cotton fibers and .[.any of.]. the micro-bits. 9. A gas-vapor treating mat as claimed in claim .[.7,.]. .Iadd.35, .Iaddend.which contains by weight 77.2% of glass fibers, 15.8% of polystyrene micro-bits and about 6.97% of the polyvinyl alcohol, and wherein the glass fibers are about 6.35 millimeters long and 6.3 microns 
     
     
        in diameter. 10. A gas-vapor treating mat as claimed in claim 1, which in addition to its content of glass fibers, the micro-bits and the binding agent, contains by weight of the overall content of the mat, intermixed therein (i) a particulate additive selected from any of activated carbon and gas-vapor adsorbent crystalline zeolite molecular sieve particles, and in an amount from about 2% to that amount beyond which more than insignificant dusting of carbon or molecular sieve particles from the mat would occur, (ii) a fiber-forming terephthalate polyester in a amount from about 5 to about 10%, and (iii) the cobeat in an amount of from about 2 to 
     
     
        about 30% as the binding agent. 11. A gas-vapor treating mat as claimed in 
     
     
        claim 10, wherein the particulate additive is activated carbon. 12. A gas-vapor treating mat as claimed in claim 10, wherein the particulate additive is the crystalline zeolite molecular sieve particles. .[.13. A gas-vapor treating mat as claimed in claim 11 or 12, wherein the micro-bits are those of any of an expanded styrene-polymer, a flexible 
     
     
        polyurethane, and an expanded lower polyolefin..]. 14. A gas-vapor treating mat as claimed in claim .[.13,.]. .Iadd.10, .Iaddend.wherein the polyester is any of (a') polyethylene terephthalate and (b') the dimethyl 
     
     
        terephthalate of 1,4-cyclohexane dimethanol. 15. A gas-vapor treating mat as claimed in claim 10, wherein the fiber-forming polyester is the polyethylene terephthalate polyester which is readily water dispersible, semi-dull, optically whitened, in 1.27 cm. long fibers of 1.5 denier, having a finish compatible with most anionic, cationic or nonionic binders and providing rapid and excellent dispersion with a wide variety of furnish systems and additives, and a solution viscosity at 25° C. of 770±20 of 1/2 gram when dissolved in 50 ml. of a solvent consisting by weight of 40 parts of tetrachloroethane and 60 parts of phenol; a melting point of 48.67° C., being non-shrinkable in boiling water, 
     
     
        and having elongation of 45% at break. .Iadd.16.  A fluid-permeable gas-vapor treating mat which comprises a sheet or elongated web formed from a mixture of: (a) glass fibers from 6.35 millimeters long to below a length at which said fibers are prone to roping, and from 3 to 12 microns in diameter;   (b) micro-bits of an expanded, thermoplastic polymer which is non-brittle in its initial expanded form, and is selected from a styrene polymer, and a polyolefin, selected from polyethylene, polypropylene, polybutene and polymethylpentene, said polymer micro-bits being from about 40 to about 325 microns long and from about 20 to about 325 microns wide, from substantially completely to entirely completely free of intact cells of the expanded polymer from which said micro-bits were produced, substantially without any uniformity in outline of the individual micro-bits particles, and having density from about 85 percent of, to about substantially the same as, the specific unexpanded polymer from which there was provided said expanded polymer from which said micro-bits are produced, and said micro-bits comprising from about 2 to about 50% by weight of the finished mat; and   (c) a binding agent selected from (a) a compatible organic binder insoluble in cold water and soluble in hot water and inert to the glass fibers, the micro-bits and any other mat constituent, or (b) a cobeat of cotton fibers, and any of said micro-bits, said binding agent being distributed throughout said mat, and comprising from about 2% to about 10% by weight of the finished mat when the organic binder (a) is used, or from about 5.8% to about 11% by weight of the finished mat when the cobeat (b) is   
     
     
        used. .Iaddend. .Iadd.17.  A gas-vapor treating mat as claimed in claim 16, wherein the micro-bits are those of a styrene-polymer. .Iaddend. .Iadd.18. A gas-vapor treating mat as claimed in claim 17, wherein the styrene-polymer is polystyrene. .Iaddend. .Iadd.19. A gas-vapor treating mat as claimed in claim 16, wherein the micro-bits are those of a lower polyolefin. .Iaddend. .Iadd.20. A gas-vapor treating mat as claimed in claim 19, wherein the polyolefin is polyethylene. .Iaddend. .Iadd.21. A fluid-permeable gas-vapor treating mat which comprises a sheet or elongated web formed from a mixture of: (a) glass fibers from 6.35 millimeters long to below a length at which said fibers are prone to roping, and from 3 to 12 microns in diameter;   (b) micro-bits of a flexible foamed polyurethane which are in the form of tripodal particles having generally uneven length legs, said particles comprising broken and inter-connected strand portions from adjacent cells of said flexible foamed polyurethane, said strand portions being substantially free of intact cell windows and having hook-like projections, indentations and flutes extending therefrom, said hook-like projections, indentations and flutes having been formed by the destruction of the cell windows of said flexible foam, said micro-bits comprising from about 2 to about 50% by weight of the finished mat; and   (c) a binding agent selected from (a) a compatible organic binder insoluble in cold water and soluble in hot water and inert to the glass fibers, the micro-bits and any other mat constituent, or (b) a cobeat of cotton fibers, and any of said micro-bits, said binding agent being distributed throughout said mat, and comprising from about 2% to about 10% by weight of the finished mat when the organic binder (a) is used, or from about 5.8% to about 11% by weight of the finished mat when the cobeat (b) is used. .Iaddend. .Iadd.22. A gas-vapor treating mat as claimed in claim 21   
     
     
        or 16, wherein the organic binder (a) is employed. .Iaddend. .Iadd.23.  A gas-vapor treating mat as claimed in claim 22, wherein the organic binder is polyvinyl alcohol at least 98% hydrolyzed. .Iaddend. .Iadd.24. The gas-vapor treating mat as claimed in claim 23 wherein the micro-bits are polystyrene. .Iaddend. .Iadd.25. The gas-vapor treating mat as claimed in claim 23 wherein the micro-bits are polyethylene. .Iadd.26. A gas-vapor treating mat as claimed in claim 24, which contains 77.2% of glass fibers, 15.8% of polystyrene micro-bits and about 6.97% of the polyvinyl alcohol, and wherein the glass fibers are about 6.35 millimeters long and 6.3 microns in diameter. .Iaddend. .Iadd.27. A gas-vapor treating mat as claimed in claim 22 which also includes: (i) a particulate additive selected from finely divided activated carbon or gas-vapor adsorbent crystalline zeolite molecular sieve particles, in an amount from about 2% by weight to below that at which more than insignificant dusting of the particulate additive from the finished mat would occur,   (ii) a fiber-forming terephthalate polyester in an amount of from about 2% to about 12.2% by weight of the finished mat, and   (iii) cobeat in an amount from about 2 to about 30% by weight of the   
     
     
        finished mat. .Iaddend. .Iadd.28.  The gas-vapor treating mat, as claimed in claim 27, wherein said particulate additive is activated carbon and comprises no more than 50% by weight of said finished mat. .Iaddend. .Iadd.29. The gas-vapor treating mat, as claimed in claim 27, wherein said particulate additive is gas-vapor adsorbent crystalline zeolite molecular sieve particles, and comprises no more than 75% by weight of said finished mat. .Iaddend. .Iadd.30. A gas-vapor treating mat as claimed in claim 27, wherein the polyester is polyethylene terephthalate. .Iaddend. .Iadd.31. A gas-vapor treating mat as claimed in claim 30, wherein the polyethylene terephthalate polyester is in the form of readily water dispersible, semi-dull, optically whitened, fibers having a finish compatible with most anionic, cationic or nonionic binders and providing rapid and excellent dispersions with a wide variety of furnish systems and additives, and a solution viscosity at 25° C. of 770+ 20 of 1/2 gram when dissolved in 50 ml. of a solvent consisting by weight of 40 parts of tetrachloroethane and 60 parts of phenol; a melting point of 48.67° C., being non-shrinkable in boiling water, and having elongation of 45% at 
     
     
        break. .Iaddend. .Iadd.32.  A gas-vapor treating mat as claimed in claim 21 or 16, wherein the cobeat binder (b) is employed. .Iaddend. .Iadd.33. The gas-vapor treating mat as claimed in claim 24, wherein the cobeat binder comprises cotton fibers, prepared by wet lapping, and polystyrene 
     
     
        micro-bits. .Iaddend. .Iadd.34.  A gas-vapor treating mat which comprises (a) glass fibers, of about 6.3 millimeters long and below a length at which they are prone to roping and from about 3 to about 12 microns in diameter, intermixed with (b) from about 5 to about 50% of micro-bits of thermoplastic styrene-polymer, or an expanded lower polyolefin selected from polyethylene to poly-methylpentene, each said polymer being non-brittle in its initial expanded form; said polymer micro-bits being from about 40 to about 325 microns long and from about 20 to about 325 microns wide, from substantially completely to entirely completely free of intact cells of the expanded polymer from which said micro-bits are produced, substantially without any uniformity in outline of the individual micro-bits particles, and having density from about 85 percent of, to about substantially the same as, the specific unexpanded polymer from which there was provided said expanded polymer from which said micro-bits are produced, said intermixed glass fibers and polymer micro-bits being held together in sheet or elongated web form and permeable to any of a gaseous and vaporous fluid stream by (c) a binding agent distributed throughout the intermixture of the glass fibers and micro-bits in an amount and manner sufficient to hold them together in the herein noted form and without destroying their permeability, which agent is selected from (1) a compatible organic binder insoluble in cold water and soluble in hot water and inert to the glass fibers, the micro-bits and any other mat constituent as well as to any gas or vapor or entrained droplets or aerosols and fine particles that are to contact the mat and (ii) a cobeat of cotton fibers and any of the micro-bits; whereby the mat has tensile strength from about 0.2 to about 5.3 kilograms per centimeter. .Iaddend.