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Flake ice is a loose definition of a group of ice types with irregular particle sizes. These types can be roughly grouped into two main types: ''scale ice'' and ''granular ice''. This can cause confusion as different manufacturers, industries or even geographical areas will say ''flake ice'' and mean different things. ==Scale ice== Scale ice is usually large, flat, thin pieces of ice (1-2 mm) mainly used in the commercial fishing and concrete cooling industries, typically in large quantities. Made on a large vertical or horizontal drums, scale ice is formed on either the inner or outer surface of the drum by pouring a film of water over it, then contact freezing it into a thin sheet of ice. This ice is sub-cooled down to -7°C in order to make it brittle, then cracked off by a harvesting blade. The ice then falls by gravity into the ice store. These large, flat pieces are good for layering, and are available with a single evaporator up to 50 tonnes. The vertical style of drum is usually stationary, with the ice formed on the inner surface. The harvesting blade is motor driven around this surface, cracking it off. The horizontal style of drum is usually rotating, with the ice formed on the outer surface. As the drum rotates, a stationary blade cracks the ice from the surface As the ice is made at -7°C, it can be stored in freezers below zero for prolonged storage. However, this means that the ice is cold enough to condense and freeze moisture from the air and also re-freeze its own melt-water, thus forming lumps if not used quickly during periods of storage at ambient temperature. It is best stored below zero, but in some applications such as fishing it can be stored at +2°C for moderate lengths of time without too many problems. It is mainly used in the fishing industry, particularly by processors with large ice requirements, and in the concrete industry where huge volumes are often required in hot climates, thus requiring cold storage. Most scale ice machines are in the 5 tonne to 30 tonne range, below this they can be very expensive for their size, particularly in very small machines below a tonne. Larger machines up to 50 tonnes are also available, but can be physically large at these capacities. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Flake ice」の詳細全文を読む スポンサード リンク
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