ESTUDO DA PRODUÇÃO DE BRIQUETES COM RESÍDUOS DA INDÚSTRIA DE CARVÃO COM AGLUTINANTES

Abstract

The main objective of this research was to evaluate the energetic properties of briquettes made from charcoal fines and waste glycerin from biodiesel production, coal dust was agglutinated with corn starch using glycerin as a plasticizer. In the briquettes composition, the mixture of corn starch and plasticizer was added in the proportion 20, 30, 35, 40 and 60 parts by weight to 100 parts of charcoal. The mixtures made were taken to a hydraulic briquetter laboratory, where a pressure of 105.5 kgf.cm-² and temperature of 115 ° C for 15 minutes was applied. The produced briquettes, that had the best mechanical resistance characteristics and is not fragmented when removed from the briquetter, were B15: 15 (15 g crude glycerin, 15 g starch) and B30: 10 (30 g crude glycerin, 10 g starch ). In the friability test, the briquettes showed a breaking rate along with good mechanical abrasion resistance; essential property in the transportation and storage process. The moisture content of 8% charcoal did not increase with the binders’ adding and the briquettes did not require drying after production. The gross calorific value (PCS) due to the immediate analysis showed a positive association between the calorific value and the fixed and negative carbon in the ash content. Due to the low PCS charcoal used, the PCS of the briquettes was around 20.93 MJ / kg, the analysis of the ash content was around 19%. The thermal stability of the briquettes, as determined by TGA and DSC showed a similar behavior, with a slight decrease thermal stability compared to briquette produced with pure glycerin. EDS analysis for the coal fines showed that the material does not contain heavy metals. Characterization by infrared and mass spectrometry also showed no presence of toxic aromatic compounds in the residual glycerol. This study showed possible to produce coal briquettes crude glycerin and starch, these residues can be used as an energy source.