Filter system

Claim 3

The method of claim 3 comprising the additional steps of sensing the pressure drop across the filter bag, terminating the flow of air into the filter bags as the pressure drop reaches a preselected level and thereafter removing the particles from the bags.

Claim 5

An electrically conductive woven fabric hollow filter bag containing a filter cake of particulate matter said filter bag having an electrostatic charge thereon sufficient to impart an electrostatic charge to said particulate matter and having a fabric weave such as to substantially prevent passage of particulate matter therethrough and through which gases readily pass and wherein said filter cake comprises electrostatically charged and mutually repulsed particulate matter.

Claim 6

The filter bag of claim 6 wherein the fabric comprises an electrically conductive carbon fiber cloth having a carbon content of at least about 90 percent.

Claim 7

The filter bag of claim 6 wherein the fabric comprises graphite cloth.

Claim 8

The filter bag of claim 6 wherein the carbon fabric is coated with up to about 10 percent by weight lubricant comprising a material selected from the group consisting of silicone, fluoroethylene polymers, graphite and mixtures thereof.

Claim 9

An improved filter bag system for extracting particulate matter from flowing gases, comprising: at least one hollow filter bag element having a longitudinal axis, an open end and a closed end, said filter bag having its longitudinal axis disposed substantially parallel to and in the path of a gasflow such that said gas enters said open end of said filter bag; said filter bag element comprising an electrically conductive woven fabric material having a weave which substantially restricts the flow of particulate matter therethrough while permitting the flow of gas therethrough; means coupled to said filter bag element for establishing a substantial electrical potential relative to electrical ground thereon; said filter bag element having an electrical charge thereon sufficient to impart an electrostatic charge to particulate matter present within said filter bag; and said filter bag containing therein a filter cake of electrostatically charged and mutually repulsed particulate matter.

Claim 10

The device as defined in claim 10 wherein said electrically conductive fabric comprises a carbon fiber cloth having a carbon content of at least about 75 percent.

Claim 11

The filter bag system of claim 10 wherein said filter bag contains an electrode substantially centrally located within the hollow portion of said filter bag and extending along said longitudinal axis thereof said electrode being at ground potential relative to said filter bag.

Claim 12

An improved filter bag system for extracting particulate matter from flowing gases, comprising: a housing member, a plurality of elongated filter bag elements mounted within the housing member, the filter bag elements each having an open end and a closed end and mounted in substantially parallel relation with their open ends lying substantially in a common plane, the filter bag elements comprising a woven textile of fibers having a high carbon content and wherein the weave substantially prevents the flow of particulate matter therethrough while permitting the flow of gas therethrough, and means coupled to said filter bag elements for establishing an electrostatic charge thereon.

Claim 13

The filter bag system of claim 13 comprising: means defining gas flow paths within said housing for passing particle-containing gases from an inlet region through said filter bag elements; a controllably variable source of electrical potential coupled to said filter bag elements, means disposed in the inlet region of said housing for sensing gas flow rate, and servo means responsive to said means for sensing and controlling said source of electrical potential to tend to maintain the gas flow rate substantially constant.

Claim 14

The filter bag system of claim 14 wherein said source of electrical potential varies between approximately 3,000 volts and 60,000 volts.

Claim 15

An improved filter bag system for extracting particulate matter from flowing gases, comprising: a substantially enclosed housing member having separate inlet and outlet regions; a wall member separating the inlet and outlet regions within said housing member, the wall member including a plurality of apertures therein; a plurality of first and second electrical insulator elements; a plurality of electrically conductive filter bag elements, each mounted between individual ones of said first and second insulator elements and each having an open end communicating with the associated aperture of said wall member, said filter bag elements comprising carbon cloth material having a weave which substantially restricts the passage of particulate matter therethrough; a source of controllably adjustable electrical potential; means coupled to the inlet portion of said housing member for defining therewith a settling chamber for particulate matter; means for sensing the flow rate of gases in said inlet portion; means respoNsive to the means for sensing for controlling said source of electrical potential; and cleaning means responsive to a predetermined electrical potential for cleaning the system.

Claim 16

The filter bag system of claim 16 wherein the cleaning means comprises an actuable mechanical actuator means mounted within the outlet portion of said housing and spaced apart from said wall member.

Claim 17

The filter bag system of claim 16 which includes an electrode centrally located within said filter bag elements and spaced apart therefrom which is maintained at electrical ground relative to the electrical potential of said filter bag elements.

Claim 18

The filter bag system of claim 16 wherein the cleaning means comprises means for reversing the gas flow within the system.