Thesis for the Degree of Master of Science


Year 2011
Maruf Hasan

Optimization of an industrial scale jet mill operation

The importance of jet milling is increasing in the process industries due to the high demand of the fine powder, especially in the paper, paint and ceramic industries. The high energy requirement for jet mill operation is creating a need for producing fine powder in an energy efficient way.

The aim of the Master’s Thesis work is to optimize operation of an industrial scale, new type of the jet grinding system. An optimized process would improve the production rate of the jet mill by maintaining a certain product size. An improvement in the production rate means a smaller use of energy and time to achieve a certain production target. Hence it would save both the energy as well as man-hour costs.

In the literature part of the jet mill, types of the jet mills and their operating procedures are studied. The literature part also studies the design and the process parameters of the jet mill. A new type of the jet mill named as “micropulva jet mill” is introduced in the literature part along with its basic operation principle.

The objective of the experimental part is to optimize the jet grinding system through a micropulva jet mill with respect to the solid feed rate and the classifier rotational speed by using the full factorial design. The quadratic models are developed in order to connect the response functions of the jet mill (the production rate, the product size and the recycling load) to the grinding variables (the solid feed rate and the classifier rotational speed). Another model is developed to connect the pre-feeding tank screw speed with the grinding variables of the jet mill. Finally, optimization for the production rate versus the product size is made with the help of those models.

It has discovered that an increase in the solid feed rate and a decrease in the classifier rotational speed result a higher production rate in the jet mill.

This info last modified 24 Sep 2017 by Jerri Kämpe-Hellenius