Air-treatment apparatus and methods

An air-treatment apparatus, comprising:

• housing means enclosing an interior space, said housing means defining air-intake-opening means for allowing passage of air into the interior space for treatment in the interior space, and air-output-opening means for allowing treated air to exit the interior space;
• gas-filter means, situated within the interior space, for receiving air entering through said air-intake-opening means, said gas-filter means comprising dual-media-filter means including a matrix of fibers and particles of activated carbon adhered to the fibers of the matrix at mutual points of contact without using an extraneous binder, the particles of activated carbon being configured to adsorb compounds including volatile organic compounds from the air as the air passes through said gas-filter means;
• and
• at least one electrostatic 3-dimensional (E3D) filter means situated within the interior space downstream of the gas-filter means so as to receive and pass air that has passed through the gas-filter means, each E3D filter means comprising respective charging-element means sandwiched between respective dielectric-fiber-matrix means that are sandwiched between respective electrically grounded screen means, said charging-element means being electrically conductive and being connected to a source of high-voltage DC power so as to impose electrical potentials on fibers of the dielectric-fiber-matrix means sufficient to polarize and attract particles in the air passing through the at least one E3D filter means.

An apparatus for treating air, comprising:

• a housing enclosing an interior space, the housing defining an air-intake opening through which air enters the interior space for treatment, and an air-output opening through which treated air exits the interior space;
• a gas-filter assembly situated within the interior space so as to receive air entering through the air-intake opening, the gas-filter assembly being permeable to air-flow therethrough and comprising an upstream pre-filter and a downstream dual-media filter element, the pre-filter comprising a matrix of fibers sufficient for removing large particulate matter from air passing through the pre-filter, the dual-media filter element comprising a matrix of fibers to which particles of activated carbon are adhered at mutual points of contact without using an extraneous binder, the particles of activated carbon being configured to adsorb compounds including volatile organic compounds from the air as the air passes through the dual-media filter element;
• at least one electrostatic 3-dimensional (E3D) filter assembly situated within the interior space downstream of the gas-filter assembly so as to receive and pass air that has passed through the gas-filter assembly, each E3D filter assembly comprising a respective charging element sandwiched between two respective dielectric-fiber filters that are sandwiched between two respective electrically conductive screens that are electrically grounded, the charging element comprising a porous matrix coated with electrically conductive carbon and being electrically connected to a source of high-voltage DC power so as to electrically charge the charging element and thus impose electrical potentials on the fibers of the dielectric-fiber filters sufficient to polarize and attract particles in the air passing through the at least one E3D filter assembly;
• a UV lamp situated and configured to illuminate a respective upstream surface of the at least one E3D filter assembly with UV light comprising a germicidal wavelength but not an ozone-generating wavelength;
• and
• at least one fan situated and configured to urge a flow of air into the air-intake opening, through the gas-filter assembly, past the UV lamp, through the at least one E3D filter assembly, and out through the air-output opening.

A method for treating air, comprising:

• removing volatile organic compounds from the air by passing the air through a dual-media filter element including a matrix of fibers to which particles of activated carbon are adhered at mutual points of contact without using an extraneous binder;
• after passing the air through the dual-media filter element, removing particulate matter and microorganisms from the air by passing the air through an electrostatic 3-dimensional (E3D) filter assembly comprising an air-permeable, electrically conductive charging element sandwiched between upstream and downstream dielectric-fiber filters that are sandwiched between upstream and downstream electrically conductive screens that are electrically grounded, while the charging element is being energized with high-voltage DC power so as to impose electrical potentials on the fibers of the dielectric-fiber filters, thereby causing the fibers to polarize and attract particles in the air passing through the E3D filter assembly;
• and
• while passing the air through the E3D filter assembly, irradiating the upstream screen and upstream dielectric-fiber filter of the E3D filter assembly with a germicidal wavelength of UV light so as to kill microorganisms trapped on said screen and filter.

A method for treating air, comprising:

• providing a housing defining an interior space, an air-intake opening, and an air-output opening;
• situating in the interior space a dual-media filter element relative to the air-intake opening so as to receive air from the air-intake opening, the dual-media filter element including a matrix of fibers to which particles of activated carbon are adhered at mutual points of contact without using an extraneous binder;
• situating in the interior space an electrostatic 3-dimensional (E3D) filter assembly relative to the dual-media filter element and air-output opening so as to receive air from the dual-media filter element and to discharge air, passing through the E3D filter assembly, through the air-outlet opening, the E3D filter assembly comprising an air-permeable, electrically conductive charging element sandwiched between upstream and downstream dielectric-fiber filters that are sandwiched between upstream and downstream electrically conductive screens that are electrically grounded, while the charging element is being energized with high-voltage DC power so as to impose electrical potentials on the fibers of the dielectric filters that cause the fibers to polarize and attract particles in the air passing through the E3D filter assembly;
• introducing air into the interior space through the air-intake opening;
• removing volatile organic compounds from the air by passing the introduced air through the dual-media filter element;
• after passing the air through the dual-media filter element, removing small particulate matter and microorganisms from the air by passing the air through the E3D filter assembly;
• and
• while passing the air through the E3D filter assembly, irradiating the upstream screen and upstream dielectric-fiber filter of the E3D filter assembly with a germicidal wavelength of UV light so as to kill microorganisms trapped on said screen and filter.