Swept surface heat exchanger

In a swept surface heat exchanger having a pair of concentric cylinders forming between them a first passage for throughflow of a first heat exchange medium, the inner cylinder defining a treatment chamber for throughflow of a product to be heated or cooled by said medium, a rotor comprising a shaft mounted for rotation in said chamber substantially on the axis of said inner cylinder, the shaft having a cylindrical outer surface and forming a second passage for throughflow of a second heat exchange medium to heat or cool said outer surface, a plurality of tubes each having opposite ends secured to the shaft and each having an intermediate portion extending outside the shaft in spaced relation to said outer surface thereof, one end portion of the shaft having a medium inlet leading via the shaft to adjacent ends of said second passage and said tubes, the other end portion of the shaft having a medium outlet to which adjacent ends of said second passage and said tubes lead via the shaft, scraper means protruding from the rotor between adjacent tubes and operable to sweep the inner surface of said inner cylinder, and stationary means surrounding said first end portion of the shaft in sealed relation thereto for supplying said second medium to said medium inlet.