Powder coating booth with improved cyclone separator

A cyclone separator comprising:

• a cyclone separator housing with a cylindrical portion and a frustoconical converging portion;
• a powder laden air inlet mounted in substantially tangential orientation to said cylindrical portion;
• a tubular member having a first end extending into said cylindrical portion and a second opposite end terminating outside of said cyclone separator housing;
• and
• a perforated thimble formed of a cylindrical wall with an inner surface free of inwardly facing protrusions, said cylindrical wall having a clean air outlet end secured to said first end of said tubular member within said separator housing and a clean air inlet end of said cylindrical wall closer to said frustoconical converging portion, said perforated thimble having a plurality of openings through said cylindrical wall permitting air transfer between an outer vortex of powder laden air flowing along an outer surface of said cylindrical wall and an inner vortex of clean air flowing along the inner surface of said cylindrical wall.

The process of recovering powder with a cyclone recovery system including the steps of:

• providing a cyclone separator housing with a cylindrical portion, a frustoconical converging portion mounted to said cylindrical portion, a tubular member having a first end extending into said cylindrical portion and mounted to one end of a perforated thimble, said perforated thimble formed of a cylindrical wall with a plurality of openings therethrough and having an open opposite end disposed in said cyclone separator housing;
• directing an outer vortex of powder laden air spiraling in a first direction between said tubular member, said perforated thimble and said cyclone separator housing for separating said powder laden air into powder and cyclone cleaned air;
• directing said cyclone cleaned air into the open opposite end of the perforated thimble so that an inner vortex of said cyclone cleaned air is spiraling in a second direction opposite to said first direction through said perforated thimble and then into said tubular member;
• and
• establishing the location of the boundary between said outer vortex of powder laden air spiraling in said first direction and said inner vortex of cyclone cleaned air spiraling in said second direction with said plurality of openings through said cylindrical wall.

A cyclone recovery system, said system comprising:

• a cyclone module containing at least one cyclone separator for extracting powder from a stream of powder laden air, said at least one cyclone separator having a cyclone inlet to draw said stream of powder laden air into said cyclone separator, a cyclone powder outlet through which powder is removed from said cyclone separator, and a cyclone air outlet through which cyclone cleaned air is exhausted from said cyclone separator;
• a final filter section having at least one final filter element for separating said cyclone cleaned air from remaining powder and exhausting final filter cleaned air;
• and
• a fan section between said cyclone module and said final filter section, said fan section having at least two serially arranged fan assemblies to direct said cyclone cleaned air from said cyclone module, through said fan section, and through said final filter section.

A powder coating system comprising:

• a booth, said booth having at least one powder spray gun opening, at least one booth exhaust opening for oversprayed powder coating material conveyed in a stream of powder laden air, and entrance and exit openings for articles to be conveyed through said booth to be powder coated;
• a cyclone module including at least one substantially non-vertically disposed cyclone separator for extracting powder from the stream of powder laden air, said at least one cyclone separator including a cyclone separator housing having a cylindrical portion and a frustoconical converging portion terminating at a cyclone powder outlet mounted in a substantially tangential orientation to said cyclone separator through which powder is removed from said cyclone separator, a cyclone inlet disposed in tangential relation to said cylindrical portion and through which said stream of powder laden air is drawn through said booth exhaust opening into said cyclone separator, and a cyclone air outlet through which cyclone cleaned air is exhausted from said cyclone separator;
• and
• a pump attached to said cyclone powder outlet.

A process for recovering oversprayed powder coating material from a powder coating operation in a powder coating booth with a cyclone recovery system, including the steps of:

• transporting articles to be powder coated into the powder coating booth;
• spraying powder coating material toward the articles with some powder coating material adhering to the articles and some powder coating materials not adhering to the articles and forming oversprayed powder;
• drawing oversprayed powder out of the powder coating booth as a stream of powder laden air and into the cyclone recovery system;
• extracting powder from the stream of powder laden air, said step of extracting powder from the stream of powder laden air including the steps of:
• drawing said stream of powder laden air through a cyclone module containing at least one substantially horizontally disposed cyclone separator for removing powder and discharging powder separated from said stream of powder laden air through a tangential powder outlet of said cyclone separator and exhausting cyclone cleaned air through a cyclone air outlet of said at least one cyclone separator;
• and
• separating residual powder from said cyclone cleaned air with a filter module containing a plurality of filter cartridges and exhausting filter cartridge cleaned air.