Patent ID: 7207376

Claim:
An apparatus for heating and cooling a liquid by exposing said liquid to an annulus between two scraped surfaces, each having a substantially different temperature relative to said liquid, said apparatus comprising: an outer body having a first surface, and having first and second ends each closed by a gate wall; an inner body having a wall with a second surface and arranged within said outer body with said second surface facing said first surface to create said annulus forming an annular transfer passage having an inner wall defined by said second surface and an outer wall defined by said first surface of said outer body for receiving said fluid to undergo heat exchange; means for effecting heat exchange with said annular passage from inside a cavity in the inner body and from outside a cavity in the outer body; inlet and outlet passages communicating with said annular passage to allow for introduction and removal of said fluid to undergo heat exchange; means for scraping said first and second surfaces comprising one or more strands of longitudinal scrapers protruding from longitudinal grooves in said inner wall and said outer wall; and means for applying a reciprocal angular movement of said inner body and said outer body in relation to each other in such a way that the relative angular movement of said first and second surfaces is implemented without collision between said scrapers in said inner wall and said scrapers in said outer wall, such angular movement being a function of the number of scraper elements in each respective body wall.