Experimental Investigation on the Influence of Ultrahigh Pressure Cold Briquetting Characteristics with Binders for Pulverized Coal in Hami Area

Briquetting is a crucial component of clean coal technology. Pulverized coal from Naomao Lake coal mine in Hami area was selected as experimental sample to investigate the effects of binder and moisture content on briquette quality. The results show that binders can enhance relax density, compressive strength, hydrophobicity and durability. And, binder type has a significant impact on energy consumption during briquetting process. For cement and clay, as addition ratio increases, briquetting energy consumption also increases. For bentonite and sodium humate, addition ratio has a small impact on briquetting energy consumption. In addition, compressive strength, hydrophobicity and durability of briquettes gradually increase with the enhancement of moisture content. Moisture can provide effective lubrication during moulding process, reducing friction between raw materials and between raw materials and mold. Afterward, by using the PCA method, a new comprehensive evaluation index was established to investigate the influence of binder type and binder ratio on the quality characteristics of pulverized coal briquetting. The results show that comprehensive evaluation index of briquettes gradually increases with the enhancement of binder ratio, and the briquette containing 15% sodium humate has the highest comprehensive evaluation index, which confirms the reliability of the proposed evaluation method for briquette quality.