“…The average value of the group is 17.6%. High values of ash in briquettes, higher than 20%, have also been found in other papers [ 22 , 23 ]. The presence of such a high value is due to the use of binding agents added to this product, for example corn starch or clay, needed to improve the compaction of the briquette and that may represent up to 5.0% of the material [ 4 , 34 , 38 ].…”