Filtration media
AssigneeDonaldson Company, Inc.
InventorsDerek O. Jones, Klenton T. Willis
Life of this patent
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Abstract
This disclosure describes a filtration medium that is preferably glass-free or substantially glass-free. In some embodiments, the filtration medium preferably exhibits capacity and efficiency comparable to or better than similar glass-containing filtration media. The filtration medium includes bicomponent fibers, efficiency fibers (for example, PET fibers), and microfibrillated fibers. The efficiency fibers include fibers having a fiber diameter in a range of 1 micron to 5 microns and fibers having a fiber diameter of at least 0.1 micron and less than 1 micron.
Claims18
A nonwoven filtration medium comprising:
- 25 wt-% to 75 wt-% of a bicomponent fiber having a fiber diameter in a range of 5 microns to 25 microns and a fiber length of 0.1 cm to 15 cm;
- 10 wt-% to 25 wt-% of a small efficiency fiber comprising a meltable polymer and having a fiber diameter of at least 0.6 micron and less than 1 micron;
- 10 wt-% to 50 wt-% of large efficiency fiber having a fiber diameter in a range of 1 micron to 4 microns;
- and
- 10 wt-% to 25 wt-% of a microfibrillated cellulosic fiber, having a different chemical composition than the small efficiency fiber, wherein a majority of the microfibrillated cellulosic fibers have a lateral dimension of 0.5 micron to 2 microns;
- wherein the nonwoven filtration medium is substantially free of glass fiber.
A method of filtering a liquid stream, the method comprising:
- passing a liquid stream comprising a contaminant through a nonwoven filtration medium, the nonwoven filtration medium comprising:
- 25 wt-% to 75 wt-% of a bicomponent fiber having a fiber diameter in a range of 5 microns to 25 microns and a fiber length of 0.1 cm to 15 cm;
- 10 wt-% to 25 wt-% of a small efficiency fiber comprising a meltable polymer and having a fiber diameter of at least 0.60 micron and less than 1 micron;
- 10 wt-% to 50 wt-% of large efficiency fiber having a fiber diameter in a range of 1 micron to 4 microns;
- and
- 10 wt-% to 25 wt-% of a microfibrillated cellulosic fiber, having a different chemical composition than the small efficiency fiber, wherein a majority of the microfibrillated cellulosic fibers have a lateral dimension of 0.5 micron to 2 microns;
- wherein the nonwoven filtration medium is substantially free of glass fiber, and removing the contaminant from the liquid stream.
A nonwoven filtration medium comprising:
- 25 wt-% to 50 wt-% of a bicomponent fiber having a fiber diameter in a range of 10 microns to 20 microns and a fiber length of 0.1 cm to 15 cm, the bicomponent fiber comprising PET and a binder polymer selected from a group consisting of copolymer PET, polyethylene, PET, nylon, polypropylene, polytetrafluoroethylene, polyethersulfone, polyphenylene sulfide, a meta-aramid, a para-aramid, poly lactic acid, ethylene vinyl alcohol, polyvinyl chloride, polyvinylidene fluoride, or a combination thereof;
- 10 wt-% to 25 wt-% of a small efficiency fiber having a fiber diameter of at least 0.6 micron and less than 0.8 micron, the small efficiency fiber comprising a meltable polymer selected from a group consisting of nylon, an acrylic, rayon, polypropylene, polyethylene, ethylene vinyl alcohol, poly lactic acid, polyvinyl alcohol, polyvinyl chloride, polytetrafluoroethylene, or a combination thereof;
- 10 wt-% to 50 wt-% of large efficiency fiber having a fiber diameter in a range of 1 micron to 4 microns, the large efficiency fiber comprising a meltable polymer selected from a group consisting of nylon, an acrylic, rayon, polypropylene, polyethylene, ethylene vinyl alcohol, poly lactic acid, polyvinyl alcohol, polyvinyl chloride, polytetrafluoroethylene, or a combination thereof;
- and
- 10 wt-% to 25 wt-% of a microfibrillated cellulosic fiber, wherein a majority of the microfibrillated cellulosic fibers have a lateral dimension in a range of 0.5 micron to 1.5 micron;
- wherein the nonwoven filtration medium is substantially free of glass fiber.
Dependencies are inferred from the claim text.