Influence of moisture and particle size on coal blend bulk density

Abstract

Coal blend bulk density is an important property in the coking process. Some variables, such as moisture and particle size, which are controlled or measured in the coal beneficiation process in steel mills, exert a strong influence on this feature. This study aims to understand the density variation of coal blends by the influence of moisture and particle size when using dry and wet bases. The investigations showed that higher density can be reached when drying the coal blend or even with excess of moisture by an agglomeration process. However, for a coal blend of lower moisture content, such as 4%, the better effects on the coking process are evident. Changes on the density from particle size require care, since they can fall in a region of high density achieved by larger particles or in a region with excess coal fines, where either or both can compromise the coke quality.

Cross-Linked Microencapsulation of CO2 Supercritical Extracted Oleoresins from Sea Buckthorn: Evidence of Targeted Functionality and Stability

“…Bulk density is an important property of powders, since it determines whether the weight of the powder will fit into its package [47]. Bulk and tapped density values of the analyzed powders were low, and between the samples, no significant (p > 0.05) differences were observed (Table 1).…”

“…According to Man et al [53], during freeze drying, large particles are formed. A large particle size means low exposed surface area and low water absorption [47,54]. The presence of WPC in the encapsulation matrix can reduce the hygroscopicity of the powder, due to its film formation characteristics [55].…”

Physico-chemical characteristics of pulverized coals and their interrelations—a spontaneous combustion and explosion perspective

“…The average bulk density of pulverized coals increased from 0.63 to 0.97 g/cm 3 , or increased by 1.54 times, with increase in the particle size from <38 to 425-850 µm. The reason behind decrease in bulk density with decrease in the particle size is attributed to the fact that with decrease in particle size, the total surface area and voids between the particles are increased, which results in decrease of bulk density due to increase in the volume of coal particles (Braga et al, 2019). Elliott (1981) and Braga et al (2019) also demonstrated that for the same moisture content, bigger coal particles have higher bulk density.…”

“…The reason behind decrease in bulk density with decrease in the particle size is attributed to the fact that with decrease in particle size, the total surface area and voids between the particles are increased, which results in decrease of bulk density due to increase in the volume of coal particles (Braga et al, 2019). Elliott (1981) and Braga et al (2019) also demonstrated that for the same moisture content, bigger coal particles have higher bulk density. Moreover, in the coal particles of higher size range, the inert petrographic materials having higher hardness and resistance to crushing are concentrated and thus, the bulk density of pulverized coals increases with increase in the particle size (Silva et al, 2011).…”

“…Bulk density is a useful parameter in the characterization and handling of coal. Under a given processing condition, the bulk density of coal is significantly affected by the particle size distribution and moisture content among many other factors (Yu et al, 1995;Braga et al, 2019). In contrast, coal dust explosion and spontaneous combustion of coal leading to fire are the two major threats to the safety of coal mines, process industries and utilities sector (Amyotte et al, 2003;Yuan et al, 2015;Yong et al, 2019).…”