Quality of eucalyptus wood chips for bioenergy as a function of drying time and horizontal chipper settings.

The increase in the use of energy from forest biomass has increased the demand for knowledge about tree-chipping operations. Therefore, this study aimed to evaluate the effect of different drying times of wood logs and various combinations of knife and anvil configurations in the horizontal chipper on the quality of Eucalyptus dunnii chips produced for energy purposes. The study was conducted in a seven-year-old stand of E. dunnii. A horizontal chipper was used to chip whole trees and obtain nine types of chips, resulting from the interaction between the three drying times of the trees and three configurations of the horizontal chipper. The chips were characterized, followed by an evaluation of energy quality for comparison between the treatments. Among the outcomes discerned, it became evident that the employed wood exhibited a Basic Density (0.506 g.cm-³). The chip dimensions and bulk density presented notable disparities owing to the distinct chipper configurations and tree drying time. The extended drying period (150 days) conferred a lower average moisture content (34.20%) to the study materials. Moreover, the ash content was lower in the treatment with 150 drying days (0.52%). Both the useful calorific value and the Fuel Value Index were also greater in the treatment (150 drying days), measuring 2600.00 kcal kg-1 and 128.06 cal cm-3, respectively. In the analysis of the Fuel Value Index concerning chipper configurations, it was observed that for chips featuring a granulometry of 25 mm, the treatment involving 150 days of drying, four knives, and one shim proved the most efficient (Q = 0.979). Conversely, for chips with a granulometry of 16 mm, the treatment involving 150 days of drying, eight knives, and one shim emerged as the most efficient (Q = 0.970). Consequently, the proposed index is efficacious and underscores the necessity of adapting knife settings in response to moisture content changes to maintain the desired granulometry and apparent density standards.

Performance of eucalypt particleboard with the addition of farm waste.

Wood residues, as well as those from poultry farming, are generally disposed of irregularly, which causes damage to the environment, and thus poses a great challenge in terms of their use, a possible alternative is the manufacture of particleboards. For this, the following mechanical properties of the panels were evaluated: static bending (elasticity - MOE and rupture - MOR), internal bond strength (IB), Janka hardness (DJ), screw withdrawal resistance (SW), thickness swelling (TS), water absorption (WA), moisture, apparent density (DA) and density profile, in addition to morphological characterization by scanning electron microscope image. With the results obtained, it was possible to observe that the amount of residue influenced the density of the panel. The panel compaction ratio showed little variation (1.22-1.32), remaining close to the value considered ideal of 1.33. The percentage of waste added to the panels also influenced the increase in WA and TS, limiting the use of the panels to environments without humidity. The addition of the eggshell in the process negatively affected the mechanical characteristics of formulated particleboards, except for Janka hardness. The application of the resin together with the wood particles and eggshells can improve the mechanical properties. Based on the findings from this study, the medium-density particleboard produced can be used for making furniture and room partitioning without structural character.

Allocation of water reservoirs to fight forest fires according to the risk of occurrence.

Although forest fires are indispensable for some ecosystems, they can have profound economic, environmental, and social implications, especially when they reach high intensities. There are two crucial factors in fighting forest fires: the availability of water resources and the service network. The objective of this study was to propose an alternative methodology for allocating water reservoirs to fight forest fires. The research was divided into three stages: zoning of fire risk, delimitation of viable areas for the implementation of water reservoirs, and determining strategic locations for reservoir allocation. The variables analyzed were land use and occupation, provision of watercourses, relief orientation, slope, proximity to roads, temperature, and precipitation. Fuzzy logic, Euclidean distance, and network analysis were used as the modeling techniques. Scenarios with all risk classes and only the high- and very high-risk classes were analyzed. A total of 66% of the area was represented by the low- and moderate-risk fire classes and 53.16% had a low potential for reservoir allocation, influenced by the low availability of water resources in the area. The proposed model efficiently allocated the water collection points in the different scenarios, and allowed the determination of the areas most susceptible to the occurrence of forest fires and the optimal locations for the installation of reservoirs, with the allocation of 21 water reservoirs to attend the areas of high- and very high-risk of occurrence of fires at a safe speed (40 km h-1) and 47 reservoirs to meet all risk classes at the same speed. The proposed methodology is feasible, applicable, and adjustable and can be implemented in other conservation units and areas of economic interest.