Study on molding characteristic of binder of upgraded fine lignite

Using the upgraded fine lignite as research object,studied the relationship between the molding process factors and the strength of briquetted upgraded lignite based on the cold press forming process with composite binders,and analyzed the molding mechanism of binder by FT-IR and scanning electron microscopy.The results indicated that when the mass percentage of 1#and 2#lignite is 3 ∶ 2,the water content is 20% and the pressure is 25 MPa,the compressive strength and the dropping strength of upgraded lignite can reached to 10.45 k N and 91.34% respectively.During the molding process,the associating hydroxyl bond and chemical bond were formed by-OH and-COOH in upgraded lignite and additives made the binding powers between lignite and additives more stronger; meanwhile under the effect of molding pressure,the mechanical meshing force between coal particles increased,so increased the strength of briquetted lignite.