Control of the size and compositional distributions in a milling process by using a reverse breakage matrix approach

A method based on the reverse breakage matrix approach is proposed for controlling the effects that milling has on the particle size distribution and composition of the comminuted material. Applicability, possibilities, and limitations of the proposed method are tested on examples related to the process of wheat flour milling. It has been shown that the reverse matrix approach can be successfully used for defining the particle size distribution of the input material leading to the desired, predetermined particle size and compositional distribution in the output material. Moreover, we have illustrated that it is possible to simultaneously control both, input and output particle size distribution, together with the composition of the output material.

Comparative analysis of milling results on the tail-end reduction passages of the wheat flour milling process: Conventional vs. eight-roller milling system

Introduction of the eight-roller mill into the wheat flour milling process significantly reduces the investment costs and overall energy requirements compared to the conventional milling system. However, the conditions for controlled milling are less favorable and could result in deterioration of flour yield and quality. Paper compares milling results obtained using a conventional process and process with an eight-roller mill employed on the tail-end passages of the reduction system. At the same roll gap and under the same sieving conditions, the flour release was lower in the process with the eight-roller mill compared to the conventional milling system. By decreasing the roll gap and increasing the upper size limit (granulation) of flour in the process with the eight-roller mill it is possible to increase flour yield and decrease milling energy consumption per unit mass of flour produced. This can be achieved without deterioration of flour quality as determined by ash content.

Reduction of wheat middlings using a conventional and eight-roller milling systems

Possibilities for the rationalization of the wheat flour milling process using the eightroller mill on the 1M and 2M passages of the reduction system have been investigated. At the same roll gaps and under the same sieving conditions, the lower flour yield has been obtained using an eight-roller mill compared to the conventional milling system (5-8 %) followed by a higher energy requirements for grinding. By decreasing the roll gap setting and increasing the upper size limit of flour in the process with the eight-roller mill it is possible to increase flour yield and therefore decrease milling energy consumption per unit mass of flour produced without deterioration of flour quality as determined by ash content. With appropriate adjustments of the processing parameters in the eight-roller milling system it is possible to achieve similar milling results to those in the conventional system, while the overall investment, energy and maintenance costs are significantly lower.