AN ASSESSMENT OF THE EFFECT OF COAL BLENDING ON HARDGROVE GRINDABILITY INDEX.

Hardgrove Grindability Index (HGI) is a determining factor of energy consumption during grinding. The current study is aimed at investigating the influence of the blending behavior on HGIs of two dissimilar coal samples. In this study, one local coal sample is taken from Lakhra coal deposits and second sample is extracted from Indonesian coal reserves for empirical experiment and analysis. The total number of nine blends with different blending ratios based on the Net Calorific Value (NCV) was made. In addition, the samples were further tested for proximate and ultimate analysis, Gross Calorific Values and HGI respectively. The ASTM D409-D409M standard Hardgrove grindability tester was used for the determination of HGI of cited two coal samples. The main purpose of this study is to determine the blends that specify the optimum results those are appropriate for power sectors and cement industries. According to the above study, the blend no 2 and 3 demonstrate the optimum results for cement factories with approximately HGI 46 and 49 with sulphur content 1.01 and 1.17, whereas blend no 4 and 5 are appropriate for power sectors with approximately HGI 52 and 54 with sulphur content 1.37 and 1.58. Furthermore, the value of the blends for HGI and moisture content shows the inverse relation, as the moisture content increases HGI value decreases. Similarly, research results also determine that there is also inverse relationship between the blend value of volatile matter and total carbon with HGI. Additionally, the GCV also exhibits inverse relationship while ash and fixed carbon reveal direct relationship with the value of blends for HGI. In the same manner, sulfur also exhibits direct relation with HGI value. [ABSTRACT FROM AUTHOR]