The distribution of ash-forming elements in dried vinasse was characterized by sequentially leaching it in H2O, NH4Ac, and HCl. In addition, the release of inorganics during combustion and CO2 gasification of the vinasse at 900 degrees C in a single particle reactor was determined. Furthermore, the vinasse was ashed at 500 degrees C, and the melting behavior of the ash as a function of temperature was first predicted using FactSage thermodynamic calculations and then validated using differential scanning calorimetry (DSC)-thermogravimetric analysis (TGA) measurements. The fuel fractionation results revealed that almost all of the ash-forming elements, except Si, Al, and Fe, in the vinasse were completely water-soluble. Moreover, unlike other solid fuels, significant portions of Si, Al, and Fe in the vinasse were water-soluble, owing to its origin, juice from water extracted cane stalks, and acidic nature. Analysis results of the ashes from the combustion and gasification experiments showed that none of the water- and acetate-soluble Si, AI, Fe, and P in the vinasse was released during combustion and gasification. However, significant levels of the water- and acetate-soluble K, Na, Ca, Mg, S, and Cl were released during the vinasse thermal conversion in both gas conditions, with the release levels being higher in CO2 than in O-2. The thermodynamic calculation and DSC-TGA measurement results showed that the initial melting temperature of the vinasse ash was 640-645 degrees C, and the temperatures corresponding to 15 and 70% melt fractions were 650 and 670-690 degrees C, respectively. The low-temperature melting ash and the release of significant amounts of water- and acetate-soluble alkali and alkali chlorides during thermal conversion suggest that vinasse is a challenging fuel for combustion and gasification in conventional boilers and gasifiers.