RHEOLOGICAL PROPERTIES AND STABILITY OF COAL-ORGANIC-WATER DISPERSED SYSTEMS BASED ON COAL OF DIFFERENT METAMORPHIC GRADES

As a result of studying the rheological properties of coal suspensions with a water-glycerol dispersion media, it was established that with an increase of the stage of coal metamorphism, that is, from the transition from lignite coal to anthracite, the suspensions are characterized by lower values ​​of effective viscosity with the same mass content of the dispersed phase. Dependence of granulometric composition of coal suspensions depending on concentration of glycerol in them was determined. Coal suspensions of varying degrees of metamorphism have been obtained using as a dispersion media glycerol, pyrolysis products of  high molecular weight polymers and water in various ratios with a maximum content of coal of 60% by weight. and permissible viscosity (up to 1.5 Pa · s). It is important that water-glycerol suspensions of coal do not decompose within a week when stored in static conditions, even in the absence of stabilizing reagents. In this case, water-cooled suspensions under the same conditions are stable for no more than 24 hours. The structure of the sedimentation of coal suspensions also depends on the nature of the dispersion media. If in systems with glycerol content it is rather loose, then in the case of coal-water suspensions - a dense. In the case of hermetic storage, the viscosity of water-glycerol suspensions after stratification is easy to restore by simple mixing. Also, the advantage of preparing of coal disperse systems with the content of glycerol is much higher values ​​of it caloric content, compared with coal-water. It iwas shown that these fuel disperse systems have high stability and caloric content, which at high solids content and pyrolysis products is close to or exceeds the output coal. The resulting suspensions have a much higher caloric content than similar coal-water, and are characterized by low emissions of harmful gases during combustion.