What is the principle of roller mill?

What is the principle of roller mill?

This mill works on the principle of compression by applying stress. Stress is applied by rotating heavy wheels or rollers. Roller mill consist of two cylindrical rollers made up of stone or metal where rollers have diameter ranging from few mm to a meter.

What is VRM in cement plant?

Vertical roller mills have long been recognised as the industry standard for raw mills – and are quickly gaining ground as cement grinders. The vertical roller mill (VRM) is well known as the preferred mill for grinding of raw materials.

How does a cement mill work?

Cement manufacturing – brief description of a cement mill This is essentially a large rotating drum containing grinding media – normally steel balls. As the drum rotates, the motion of the balls crushes the clinker. The drum rotates approximately once every couple of seconds.

How much moisture can you feed in VRM?

Raw Materials (Raw Mix) Input Size & Product (Raw Meal) Size. Generally, Roller mills can accommodate high size (up to 80–100 mm) and high moisture (20 %); whereas Ball Mills can normally accommodate (up to 25 mm) & moisture up to 12 %.

What is the size reduction?

Size reduction is a process in which particles with smaller size and large surface areas are formed, which ultimately eases the processing. The chapter explains the size reduction mechanism during compression, impact, cutting, shearing, and attrition.

What is the difference between VRM and ball mill?

Operation of a ball mill is relatively simple, with no moving mechanical parts within the mill itself. The system is tolerant to variations in both mill feed quality and quantity. By contrast, the VRM is a more complex piece of equipment with a sophisticated hydraulics system that operates the rollers.

What is preheater in cement plant?

Preheaters are used industrial dry kiln cement production plants to heat the raw mix and drive off carbon dioxide and water before it is fed into the kiln. An analytical model of a generalized four-stage suspension cyclone preheater system is presented.

What is the formula for cement?

Chemical Formulas of Cement Materials

What is mill differential pressure?

Differential Pressure. The mill differential pressure is the difference between pressure at mill inlet and mill outlet.

What is size reduction principle?

Size reduction is a mechanical process of breakdown of solids into smaller size particles without altering the state of aggregation of solids. Many solid materials exists/present in sizes that are too large to be used directly. Thus such material must be reduced in size before use. 13.1 Necessity of size reduction.

What are the types of size reduction?

Size reduction is a unit operation process and the operations include grinding, compression and impact forces. The types of forces involved are compression, impact and attrition forces.