Main parts of this system are two drums, which are heated with steam by the inside and rotate.
As for two drums, a feed-box is made between the drums facing each other and two end-boards attached to this drum ends, and raw liquid is sent here (cf. cross section).
Gap between the drums can be adjusted even during rotation.
Raw liquid supplied in the feed-box is evaporated and concentrated therein, passed through the appropriately adjusted gap between the drums, scraped with the knives mounted to the upper part of the drums respectively, then collected in one area through conveyer. Vapor generated is collected in the hood covering the upper part of the drums to discharge through the exhaust duct.