Abstract: The present invention relates to a reaction or separation device, wherein the materials circularly flow in a container and a pipe. Said device contains a container and an external circular pipe, wherein the container is a double-chamber structure. The inner chamber consists of an outer cylinder and an inner cylinder with the latter being jacketed by the former, and there is a space between the walls of the outer cylinder and the inner cylinder. The lower end of the outer cylinder is open and higher than the bottom of the container, and the outer cylinder is fixed to the wall or bottom of the container. The upper end of the inner cylinder is open and its lower end connects with the external circular pipe through the feed outlet.