# US 11,298,644 B2 · Drainage medium for gas filter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,298,644 B2 - Document ID: US11298644B2 - Status: Granted - Kind: B2 - Application number: 16/620,558 - Filed: 2018-06-12 - Published: 2020-05-21 - Granted: 2022-04-12 - Earliest claimed: 2017-06-12 - Assignees: Atlas Copco Airpower, Naamloze Vennootschap - Applicants: Atlas Copco Airpower, Naamloze Vennootschap - Inventors: Ken Goris; Jo Wouters; Evi Marcel J. Bultinck; Isabelle Denise M. De Wolf - Web page: https://patentgrep.com/patent/US11298644B2 ## CPC - B01D 17/045: {with coalescers} - B01D 46/0031: {with collecting, draining means} - B01D 46/0047: {for discharging the filtered gas} - B01D 2201/184: Special form, dimension of the openings, pores of the filtering elements - B01D 2239/0609: Knitted - B01D 2239/0613: Woven - B01D 2239/1208: Porosity - B01D 2239/1216: Pore size - B01D 2239/1258: Permeability - B01D 2258/06: Polluted air - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract A coalescence filter including an inlet for supplying the gas to a filter element present in the coalescing filter, which filter element includes a coalescence medium for coalescing at least one disperse liquid phase during a displacement of a gas through the coalescence medium in a flow direction. The filter element downstream of the coalescence medium includes a drainage medium for draining the at least one coalesced disperse phase leaving the coalescence medium. The filter element contains a barrier layer positioned downstream of the coalescence medium, where the coalescence medium and the barrier layer are held at a distance from each other by one or more spacers to provide a drainage zone in the drainage layer of a drainage medium between a surface of the coalescence medium facing the barrier layer and the barrier layer for draining the coalesced disperse phase in a drainage direction. ## Claims ### Claim 1 A gas filter for coalescing at least one dispersed liquid phase present in a gas, the gas filter comprising: an inlet for supplying the gas to a filter element present in the gas filter, which filter element comprises a coalescence medium for coalescing the at least one dispersed phase during a displacement of the gas through the coalescence medium in a flow direction, wherein the filter element downstream of the coalescence medium comprises a drainage medium for draining the at least one coalesced dispersed phase leaving the coalescence medium in a drainage direction which is transverse to the flow direction, wherein the filter element is composed of a single package of the coalescence medium, the drainage medium and a barrier layer, wherein the barrier layer is located downstream of the coalescence medium, wherein the coalescence medium and the barrier layer are held at a distance from each other by one or more spacers extending in the flow direction to provide a drainage layer in the drainage medium between the barrier layer and a surface of the coalescence medium facing the barrier layer, the coalescence medium, the drainage medium and the barrier layer being layer-like materials positioned adjacent to each other, wherein pores in the drainage medium have an average pore diameter greater than an average pore diameter of pores of the barrier layer and greater than an average pore diameter of pores of the coalescence medium, wherein the drainage medium has a thickness greater than a thickness of the coalescence medium and a thickness of the barrier layer, wherein the drainage medium contains the drainage layer with a drainage surface for receiving and draining the at least one coalesced dispersed phase, the drainage surface facing the coalescence medium, wherein the drainage medium contains an anisotropic porous material having a higher air permeability than the barrier layer, and wherein the barrier layer is positioned downstream of the drainage medium, the drainage medium having a permeability for the at least one coalesced dispersed phase in the drainage direction which is higher than a permeability in the flow direction of the fluid. ### Claim 2 (depends on 1) The gas filter according to claim 1, wherein the drainage medium further comprises a capturing layer for capturing the coalesced dispersed phase from the coalescence medium and guiding the coalesced dispersed phase to the drainage layer, wherein the capturing layer contacts a surface of the coalescence medium which faces the drainage layer. ### Claim 3 (depends on 2) The gas filter according to claim 2, wherein the capturing layer contains a material selected from a knitted fabric, a crocheted material, a tufted material, a woven fabric or a combination of two or more of the aforementioned materials. ### Claim 4 (depends on 1) The gas filter according to claim 1, wherein the pores in the drainage layer have an average pore diameter which is greater in the drainage direction than in the flow direction. ### Claim 5 (depends on 1) The gas filter according to claim 1, wherein a maximum of 10% of the pores of the drainage medium have a diameter which is smaller than 5 μm, and at least 50% of the pores of the drainage medium have an average diameter which is greater than 500 μm. ### Claim 6 (depends on 1) The gas filter according to claim 1, wherein the pores in the drainage medium have a diameter which ranges between 5.0 and 20000.0 μm. ### Claim 7 (depends on 1) The gas filter according to claim 1, wherein the drainage layer is configured to have an average pore diameter of the pores in the drainage direction greater than an average droplet size of the at least one coalesced dispersed phase. ### Claim 8 (depends on 1) The gas filter according to claim 1, wherein the drainage medium has a thickness between 0.5 and 20.0 mm. ### Claim 9 (depends on 2) The gas filter according to claim 2, wherein the barrier layer has a lower permeability in flow direction for the coalesced dispersed phase than the drainage medium and the capturing layer. ### Claim 10 (depends on 1) The gas filter according to claim 1, wherein the barrier layer comprises a material with pores whose diameter is situated between 5.0 and 1000.0 μm. ### Claim 11 (depends on 1) The gas filter according to claim 1, wherein the barrier layer has a thickness between 0.01 and 20.0 mm. ### Claim 12 (depends on 2) The gas filter according to claim 2, wherein the pores of the capturing layer have a diameter in the range of 5.0 to 20000.0 μm. ### Claim 13 (depends on 2) The gas filter according to claim 2, wherein the capturing layer has a thickness between 0.1 and 20.0 mm. ### Claim 14 (depends on 1) The gas filter according to claim 1, wherein the drainage medium comprises a material selected from a knitted fabric, a crocheted material, a tufted material, a fabric, a polymeric foam, or a combination of two or more of the aforementioned materials, wherein at least a portion of the surface is facing and preferably in contact with the surface of the coalescence medium facing the drainage medium. ### Claim 15 (depends on 1) The gas filter according to claim 1, wherein the drainage medium comprises a material selected from the group consisting of a spacer textile, a spacer fabric, a spacer knitting, a polymer foam, or a combination of two or more of the aforementioned materials. ### Claim 16 (depends on 2) The gas filter according to claim 2, wherein the capturing layer comprises a material selected from a knitted fabric, a crocheted material, a tufted material, a woven fabric, a polymeric foam, or a combination of two or more of the aforementioned materials. ### Claim 17 (depends on 16) The gas filter according to claim 16, wherein the capturing layer comprises a plurality of protrusions which extend towards the coalescence medium. ### Claim 18 (depends on 16) The gas filter according to claim 16, wherein at least a part of fibers forming the capturing layer extend in the drainage direction. ### Claim 19 (depends on 2) The gas filter according to claim 2, wherein the drainage medium comprises a polymer foam, in particular a polyurethane foam, with a first foam layer for providing the drainage layer, the drainage layer containing pores which are open in the drainage direction, wherein on a downstream side of the drainage medium a second layer of a polymeric foam is provided for providing the barrier layer containing pores which are closed in the flow direction of the gas. ### Claim 20 (depends on 1) A method for separating a dispersed phase present in a fluid from a carrier using the gas filter according to claim 1, said method comprising the steps: supplying the fluid to the gas filter with the coalescence medium for coalescing the at least one dispersed phase, contacting the at least one coalesced dispersed phase when leaving the coalescence medium through a downstream exit surf ace of the coalescence medium, with the drainage medium contained in the gas filter, draining the coalesced dispersed phase along the drainage surface or through the drainage medium, and collecting the carrier present in the fluid downstream of the drainage medium.