Horizontal Emery Roller Rice Whitener

Horizontal Emery Roller Rice Whitener

Shijiazhuang Xinlu Technology Co., Ltd. – Technical Overview of Horizontal Emery Roller Rice Whitener

The Horizontal Emery Roller Rice Whitener is a central machine in the rice milling process, responsible for removing the bran layers from brown rice to produce white rice. This process, known as whitening or milling, directly impacts the appearance, nutritional content, and commercial grade of the final product. Shijiazhuang Xinlu Technology Co., Ltd. designs these whiteners to achieve a balance between high milling efficiency, low breakage rate, and controllable whitening degree.

The core component of the whitener is a horizontal shaft on which one or more emery rollers are mounted. These rollers are cylinders coated with a layer of synthetic or natural emery (silicon carbide), which provides a hard and abrasive surface. This assembly rotates at a high speed inside a stationary cylindrical screen, often made of perforated steel sheet or woven wire mesh. The gap between the rotating emery roller and the stationary screen is adjustable.

Brown rice is fed into one end of the machine and is propelled along the length of the chamber by the action of the roller and/or internal spirals. As the rice grains are forced through the narrow gap between the roller and the screen, they are subjected to a combination of friction and mild pressure. This abrasive action scrapes off the outer bran layers from the surface of the kernels. The removed bran, being fine and small, passes through the perforations of the surrounding screen and is collected separately. The whitened rice is discharged from the opposite end of the machine.

A critical aspect of the whitening process is temperature control. The friction generated during milling produces heat, which can lead to cracked kernels and a gelatinized, cloudy appearance on the rice surface, negatively affecting quality. To mitigate this, the machine is equipped with a ventilation system. The rotating shaft or the chamber design often incorporates air channels that draw ambient air through the milling chamber. This airflow serves to cool the rice and simultaneously carry the milled bran away through the screen, preventing it from building up and causing excessive heat and pressure.

The degree of whitening is controllable. Operators can adjust several parameters to achieve the desired whiteness and finish. The primary adjustment is the pressure at the rice outlet, typically controlled by a counter-weighted or spring-loaded gate. Increasing the back pressure slows the outflow of rice, increasing its residence time in the milling chamber and resulting in a higher degree of bran removal and whiter rice. Conversely, reducing the pressure produces a lighter mill. The condition of the emery roller, which wears over time, also affects milling performance and consistency, necessitating periodic inspection and replacement. The Horizontal Emery Roller Rice Whitener from Shijiazhuang Xinlu Technology Co., Ltd. is therefore a precision tool that allows millers to produce white rice that meets specific market requirements for whiteness and finish while striving to maximize the whole kernel yield.