Modeling of coal breakage in a double-roll crusher considering the reagglomeration phenomena

To represent the particle behaviors and to predict the product size distributions of coal breakage products by a double-roll crusher, a new combined breakage–agglomeration model has been constructed. The model utilizes a fair combination of individual models for two distinct phenomena, the breakage and the agglomeration which occur simultaneously in the double-roll crusher process. Thus, it is capable of representing the complicated reduction and growth in the particle size during the process. Model parameters were estimated from experimental data from single-size crushing tests. Using these parameters, product size distributions with distributed-size feed were predicted from the simulation and were compared to the experimental results. The simulated results show fairly close agreement with the experimental results with an acceptable degree of accuracy. The basic concept can be used for a description of the simultaneous breakage–agglomeration process, which involves particle shape changes during the process of agglomeration.

Graphical abstractReducing the gap of the roll crusher produces agglomerates causing size enlargement rather than size reduction.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A combined breakage-agglomeration model has been developed. ► Agglomeration takes places as the gap of the roll crushers is reduced. ► Shape of agglomerates was considered in the development of the dual-size model. ► Agglomeration probability was deduced by considering the rate of compression. ► The proposed model is potentially applicable to various types of mills.