Properties of binderless coal slime briquette via hydrothermal hot pressing dewatering

摘要

Dewatering and binderless briquetting of Liulin coal slime by hydrothermal hot pressing (HHP) method were studied under a wide range of process conditions. Fourier transform infrared spectroscopy and XRD were used for characterization. Results indicated that the optimal conditions were a pressure at 4.2 Mpa, a temperature of 150., and additive NaOH at 3.0%. The increase of temperature caused the loss of absorbed water in clay minerals and also some organic species having functional groups, such as -CH3 and -CH2. The alkalinity caused the loss of oxygen functional groups and the formation of hydroxysodalite, which reduced the water storage capacity and promoted coal particles agglomeration.