Flotation separation of Shenfu coal macerals and low temperature pyrolysis characteristics of different maceral concentrate

The flotation separation of Shenfu coal macerals and the low temperature pyrolysis characteristics of its concentrates were carried out. The effect of pulp pH value on flotation separation and the impact of maceral enrichment ratio on low temperature pyrolysis were studied. A contrastive analysis was conducted on the characteristics of maceral concentrates in low temperature pyrolysis, providing theory guidance for classifying utilization of coal macerals. The results show that the separation effect of macerals can be manipulated through adjustment of pulp pH value. The more vitrinite exists in the coal sample, the higher the tar yield in low temperature pyrolysis is. But the more inertinite existing in the coal sample highers the semicoke yield. The surface of semicoke from vitrinite concentrates shows clear holes and cracks, and the semicoke structure of inertinite concentrates becomes more dispersive and fragile and an increase in small particles is found. Shenfu coal and its various macerals concentrates show a relative high content of phenols in its tar from low temperature pyrolysis. More phenols, naphthalenes and hydrocarbons exist in the tar from vitrinite concentrates, whereas more cyclophanes and benzenes are found in inertinite tar. The gas compositions of Shenfu coal and its concentrates in low temperature pyrolysis are CH₄, H₂, CO₂ and a bit of C_2~5. The relative cumulative yield of CH₄, H₂, and C_2~5 in low temperature pyrolysis gas from vitrinite concentrates is higher than those from inertinite, but the CO and CO₂ is lower than that from inertinite. The relative cumulative yield of CH₄ and H₂ is higher in pyrolysis gas of Shenfu raw coal than that from vitrinite and inertinite.