Aiming to use lignocellulosic biomass as energy source, one of the process that may aggregate values is the densification process, which allows the production of bioenergy using solid fuels, mainly for reducing transportation costs. In this research, solid fuel from co-briquetting of wood residues from sawmill using commercial kraft lignin as binder was investigated. The effects of compression pressure (900, 1200 and 1500 PSI) and briquette formulation (varying wood and kraft lignin proportion) on the quality and characteristics of briquettes were evaluated. The main findings were that briquetting of wood residues with kraft lignin resulted in an improvement of bulk density, strength rupture modulus, low heating value (LHV) and high heating value (HHV). The briquettes using 4% and 6% of kraft lignin, and submitted to 1200 to 1500 PSI, presented higher bulk density and strength resistance, respectively. On the other hand, the heating values showed the highest results with the addition of 2% lignin at 900 PSI, being the legal range for additives in briquettes for many countries such as in European Union.

Aim of study: Fast and reliable wood identification solutions are needed to combat the illegal trade in native woods. In this study, multivariate analysis was applied in near-infrared (NIR) spectra to identify wood of the Atlantic Forest species.Area of study: Planted forests located in the Vale Natural Reserve in the county of Sooretama (19 ° 01'09 "S 40 ° 05'51" W), Espírito Santo, Brazil.Material and methods: Three trees of 12 native species from homogeneous plantations. The principal component analysis (PCA) and partial least squares regression by discriminant function (PLS-DA) were performed on the woods spectral signatures.Main results: The PCA scores allowed to agroup some wood species from their spectra. The percentage of correct classifications generated by the PLS-DA model was 93.2%. In the independent validation, the PLS-DA model correctly classified 91.3% of the samples.Research highlights: The PLS-DA models were adequate to classify and identify the twelve native wood species based on the respective NIR spectra, showing good ability to classify independent native wood samples.Keywords: native woods; NIR spectra; principal components; partial least squares regression.

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The exploitation of valuable native timber species in forest restoration projects has emerged as a promising strategy to make restoration financially viable. There are few studies regarding the quality of timber from restoration plantations. The aim of this study was to analyze growth stresses by determining the longitudinal residual strain (LRS) and evaluate their correlation with the growth variables in the species Peltophorum dubium (Spreng.) Taub in a 14-year old restoration plantation. Eighteen individuals were evaluated, determining the following variables: diameter at breast height (DBH), bark thickness, average annual growth in diameter (IMA) and annual periodic growth in diameter (IPA 2012-2015). The LRS was determined by the extensometer (CIRAD-Forêt), on DBH height and in the north-south direction of each tree. The LRS average was 0.072 mm, within the range of expected wood values for sawmilling. There was a significant positive correlation between the LRS, DBH and IMA.

The circular saw is a tool commonly used for wood processing. It may be presented at different models. Considering their specificities, they can generate different amount of waste. The objective of this study was to evaluate the generation of waste from Tectona grandis L. f. and Pinus caribaea var. hondurensis, processed with two saws of the multiple type (48 and 36 teeth) and one of the universal type (28 teeth). The cutting process followed in grain direction into ninety samples, 15 for each species and saw, until the sample was completely processed. The processing time was measured and the waste was collected in each operation. ANOVA and test of multiple comparison of averages were applied. The influence of the teeth number and type of saw on the amount of waste generated was verified. The universal saw was the one that generated the highest amount of waste. It reached up to 116% more than the multiple saw, that generated the lowest amount of waste (36 teeth). P. caribaea var. hondurensis generated 7% more waste and presented shorter processing time (22%), when compared to T. grandis.

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