Effect of Seawater with Average Salinity on the Moisture Content, Ash Content and Tensile Strength of Some Coniferous Wood.

In this paper, the differences in mechanical strength tested during the static tensile and compression test of Scots pine (Pinus sylvestris L.), European larch (Larix decidua) and Norway spruce (Picea abies) wood exposed to continuous soaking in water with a salinity of 7‱ were determined. The value of salinity corresponded to the average salinity on the Polish Baltic coast. This paper also aimed to examine the content of mineral compounds absorbed during four cycles of two weeks each. The essence of the statistical research was to identify the effect of the mineral range compounds and salts depending on the mechanical strength of the wood. Based on the results of the experiments, it can be concluded that the medium used has a specific effect on the wood species' structure. The effects of soaking on the wood parameters depend obviously on the type of wood. A tensile strength test of pine, as well as the tensile strength other species, was enhanced by incubating it in seawater. A native sample's initial mean tensile strength was 82.5 MPa, which increased to 94.8 MPa in the last cycle. It was found that the larch wood had the lowest tensile strength difference (9 MPa) of the woods studied in the current study. Four to six weeks of soaking was necessary to notice an increase in tensile strength.

Dispersed Power Production in Terms of the Potential of Briquettes Made from Straw and Willow as Renewable Sources of Energy.

The rapid development of agricultural technologies has triggered new possibilities of using plant waste as fuel. Briquetting plant material is one of the methods of using crop residue as permanent energy carriers. Nevertheless, to maintain the normalised properties of briquettes, their small-scale production should follow an established and well-considered deliberate technological process limiting production costs. The material to be used for energy production should, in particular, be pre-prepared in terms of crushing and moisture content to ensure the right product parameters. The article aims to provide an analysis of briquettes with varied physicochemical parameters to determine and order homogenous groups for selected parameters characteristic for briquettes made from various bioenergy materials. The specific aim of the article required a statistical analysis as a tool for separating the selected factors. An analysis of variance (ANOVA) was involved, together with a post-hoc Duncan test. The analyses demonstrated that the briquette composition, such as bulk value, moisture, and ash content can enhance the briquette quality. In discussion, the straw used was compared with other kinds of agricultural biomass samples and considerable differences were identified. The chemical analysis showed a high content of carbon (from 42.64 to 45.66%) and oxygen (from 47.60 to 49.68%). The percentage share of hydrogen in the chemical structure of the materials accounted for approximately 6%. The ash content found while investigating various straw types ranged from 3.67 to 4.26%, making it lower than reported in the literature. The study also looked at the energetic potential of straw and wood biomass. It was noticed that bioenergetic sources are much potentially higher than the materials used in the traditional power sector. Especially where it concerns an unlimited source that can be provided to the bio-energetic sector. The study is intended to focus the future energy sector on the use of bioenergy in terms of applying straw to energy production purposes.