Industrial & Engineering Chemistry Research, Vol.58, No.16, 6830-6840, 2019
Oil-Filled Cryogels: New Approach for Storage and Utilization of Liquid Combustible Wastes
A method of preparing oil-filled cryogels on the basis of an aqueous solution of poly(vinyl alcohol) (PVA) has been elaborated. The stability of primary oil emulsions and their rheological properties were analyzed for 30 days, as well as the mechanical properties of gel fuel pellets (obtained after 15 cycles of freezing/thawing of oil emulsions) with size of 20 mm for a group of compositions: 100-20 vol % aqueous solution of PVA (5, 10 wt %) + 0-80 vol % oil. The theological behavior of non-Newtonian oil emulsions is described by the Herschel-Bulkley model. The elastic moduli and the tensile strength of fuel pellets of different component compositions range from 0.7 to 7.6 kPa and from 2.5 to 60 kPa, respectively. The oleophilic properties are more distinct for gel fuel prepared from oil emulsions with a higher content of the dispersed phase and lower concentrations of the polymer in the dispersion medium. The ignition mechanism and combustion characteristics have been established for processes occurring under the conditions of a radiant heat supply. Gel fuels, unlike combustible liquids, are characterized by a longer induction period, but a multicomponent structure of fuel caused microexplosions that enhance the combustion process.