Apparatus for separating foreign matter from a gas with a heat exchanger

An apparatus for separating foreign matter from a hot gas and transferring heat from the hot gas to a fluid comprising:

• first means having a wall, said wall having opposite ends and a passage, and a gas inlet and a gas outlet surrounded by the opposite ends open to said passage, second means located in the passage to direct gas and foreign matter in a generally helical path into engagement with said wall, said foreign matter being collected on said wall, said collected foreign matter moving along said wall toward the gas outlet, third means fixed with respect to said wall to collect foreign matter that moves from said outlet of the passage and to permit clean gas to pass through said third means, fourth means including a jacket surrounding said wall providing chamber means accommodating a fluid located in engagement with said wall, said jacket having means along the length thereof providing said chamber with a general spiral passage for carrying fluid and directing the flow of fluid around and along the length of said wall whereby the wall is cooled and the temperature of the gas in the passage adjacent the inside surface of the wall is lowered to enhance condensation of gases into liquids which collect on said inside surface of the wall whereby heat from said hot gas in the passage is transferred through said wall to said fluid, and means for supplying fluid to said chamber means and carrying heated fluid from said chamber means.

A hood assembly for use with cooking equipment for collecting gas and foreign matter and separating the foreign matter from the gas and transferring heat from the gas to a fluid comprising:

• housing means having generally horizontal wall structure defining a chamber having an open forward side for receiving gas and foreign matter from the cooking equipment, said wall structure having a plurality of openings, a plurality of gas cleaning units located in said chamber below said openings, each of said units having an uninterrupted fluid impervious heat conducting tubular wall forming a tubular passage, said tubular wall having an inlet end open to said passage and an opening in the wall structure, and an outlet end open to said passage, means mounting said cleaning unit on said wall structure, means for moving gas and foreign matter through said passage of each unit and exhausting said gas externally of the hood assembly, each gas cleaning unit having means located in said passage along the longitudinal length thereof to direct gas and foreign matter flowing through said passage in a generally helical path extended from the gas inlet end to the gas outlet end thereof, said foreign matter entrained in the gas being collected on said wall, said collected foreign matter moving along said wall toward the gas outlet end of the passage, annular means fixed with respect to said wall to collect foreign matter that moves from the outlet end of said passage and permits clean gas to pass centrally thereof, jacket means surrounding the tubular wall providing chamber means accommodating said fluid, said fluid being located in engagement with said tubular wall whereby heat from said wall is transferred to said fluid, said jacket means having opposite ends secured to the tubular wall adjacent the gas inlet and outlet ends thereof, said jacket means having a general spiral shape along the length thereof providing said chamber means with a spiral passage for carrying fluid and directing the flow of fluid around and along the length of the tubular wall whereby the tubular wall is cooled and the temperature of the gas in the passage adjacent the inside surface of the tubular wall is lowered to enhance condensation of gases into liquids which collect on said inside surface of the tubular wall, means for supplying fluid to said chamber means, and means for carrying fluid from said chamber means to a desired location.