- For other uses see Mill (disambiguation)
A grinding mill is a tool that is designed to break a solid material into smaller pieces. There are many different types of grinding mills and many types of materials processed in them. Small mills can be powered by hand, such as a mortar and pestle or a pepper grinder. Large grinding mills were usually powered by working animals, wind (windmill) or water (watermill) in the past. In the 2000s, most large grinding mills are powered by electricity.
Types of grinding mills[change | change source]
Mortar and pestle[change | change source]
People who need to grind a small amount of a food, such as spices or grain, for their own cooking often use a hand-powered mortar and pestle or a hand-powered grinder, such as a pepper grinder. In the 2000s, many people also used electric-powered grinding mills. These kitchen appliances have a metal blade that grinds the food into small pieces. Electric-powered grinding mills are often used for grinding nuts or coffee.
Grain mills[change | change source]
For thousands of years, humans have ground their grains (such as wheat or corn) into flour using grain mills powered by working animals (such as oxen or horses), wind (windmills) or the running water of a stream or river (watermill). In the 2000s, most grain mills are powered by electricity.
Mechanical process[change | change source]
The grinding of solid matters occurs under exposure of mechanical forces that trench the structure by overcoming of the interior bonding forces. After the grinding the state of the solid is changed: the grain size, the grain size disposition and the grain shape.
For process engineering, several factors are important:magnification of the surface area of the solid; manufacturing of solid with wanted grain size; andthe material to the desired state.
A windmill has large sails that use the force of the wind to turn heavy stone grinding surfaces, to grind grains into flour
A watermill uses the force of running stream or river water to turn heavy stone grinding surfaces
A treadmill uses the force of a working animal to turn the stone grinding surfaces