Quantification and Environmental Assessment of Wood Ash from Biomass Power Plants: Case Study of Brittany Region in France

The increasing demand for energy is leading to the increasing use of renewable resources, such as biomass, resulting in the significant development of the wood energy sector in recent years. On the one hand, and to a certain extent, the sector has generated many benefits. On the other hand, the challenges related to wood ash (WA) management such as increasing tonnages, landfilling, restrictive regulations for reuse, etc., have been weighing more heavily in the debate related to the wood energy sector. However, all studies have assumed that no environmental impacts can be attributed to WA production. This study aims at discussing this assumption, whether the WA is a waste or a co-product of heat generation. In the first place, WA deposits were estimated using the biomass database and ash content from the literature regarding the collective, industrial and tertiary biomass power plants (BPP) in the French region of Brittany. Then, the impacts of the generated WA were estimated using the attributional life cycle assessment (LCA) method through two different impact allocation procedures (IAP), “from cradle to gate” (excluding the waste treatment). In Brittany, for the year 2017, an estimated amount of 2.8 to 8.9 kilotons of WA was generated, and this production should increase to 5 to 15.7 kilotons by 2050. The LCA conducted through this study gave an emission of 38.6 g CO2eq /kW h, with a major contribution from the production of the wood chips. Considering the environmental aspect, the IAP analysis indicated that energy and economic allocations were not relevant, and that, using the mass allocation, the environmental production of WA could represent 1.3% of the impacts of the combustion process in BPP. Therefore, WA, and especially the fly ash, can be considered as a waste from BPP heat production, without any environmental impact attributed to its generation.

Potential uses of the lesser-known tree: Timo (Timonius sericeus (Desf) K. Schum) from Timor Island, East Nusa Tenggara based on its chemical wood properties and calorific value

This study determined the chemical properties and calorific value of Timo (Timoneus sericeus) wood originated from Reknamo village, Timor Island, East Nusa Tenggara. Timo is a potential wood that belongs to the Rubiaceae family, categorised as the lesser known tree. Its basic wood properties have not been thoroughly scientifically investigated. The chemical wood analyses were carried out at the laboratory of chemical forest products in the Forest Products Research and Development Center, Bogor. The Testing methods were according to the ASTM and TAPPI standard, included the content of extractive solubility (in cold water, hot water, benzene-alcohol, and in 1% NaOH), cellulose, pentose, lignin, ash, and silica. The calorific value was measured by the calorimeter. The result showed that the cellulose, pentose, and extractive solubility contents of Timo wood were high; the lignin and ash contents were moderate; the silica content was low; the calorific value was high (4400 cal/g). Based on the results of chemical wood analyses and calorific value, Timo wood is qualified for construction and wood energy; while it is not recommended for pulp and bioethanol.

USE OF VERY HIGH SPATIAL RESOLUTION IMAGERY FOR MAPPING WOOD ENERGY POTENTIAL FROM TROPICAL MANAGED FOREST STANDS, REUNION ISLAND

The development of a sustainable wood energy chain is an essential part of ecological and energy transition in Reunion Island (Indian Ocean), where Acacia mearnsii is the main potential wood energy resource identified to date. In order to assess future wood biomass supply chain strategies, a major first issue is to gain knowledge of the spatial distribution of this species forest stands.In this study, we assessed the potential of very high spatial resolution multispectral imagery for mapping the main forest stands in a study area located the Western Highlands region, where Acacia mearnsii expands alongside Acacia heterophylla, an endemic forest species and Cryptomeria japonica, an exotic forest stand. A reference database including 150 samples of seven classes (Acacia mearnsii (mature and non-mature), Acacia heterophylla (mature and non-mature), Cryptomeria japonica, ‘herbaceous areas’, and ‘bare soils’) was used to classify a Pleiades image acquired in May 2020. Spectral and textural indices were used in an incremental classification procedure using a random classifier.The best results (Kappa = 0.84, global accuracy = 84%) were obtained for the classification using all spectral and textural bands. The resulting map enables analyzing the spatial distribution of the different forest stands.

Agrobiological foundations for growing woody energy crops on drained organogenic soils

The purpose of the work was to identify the most effective agrobiological measures of plantation cultivation of wood energy crops – various types of willow on drained organogenic soils of Forest-steppe and Polesie, to develop technologies for their cultivation and to carry out energy, economic and environmental assessments of their cultivation on land extracted from intensive cultivation. Research methods – field with a complex of biometric, agrochemical and laboratory studies, mathematical and statistical.The results of studies conducted on medium-deep drained old-time carbonate peatland are presented. Data on agroecological assessment of soil and climatic conditions of agricultural lands were obtained to create energy plantations in the area of excess moisture, agrochemical and water-physical properties and features of the water-air regime of organogenic soils were investigated. As a result of the analysis, the data found that they fully meet the requirements of growing high-performance energy crops.It has been established that the most effective way of basic soil processing is to plant willows in ploughed furrows with an area of food of 0,9 x0,7 m and harvest every two to three years. The most productive on average in five years was willow three-song – 27,1-28,0 t per hectare and willow rod – 23,2 and 31,7 t per hectare of dry mass in Forest Steppe and Polissya, 28,2 and 21,2 t per hectare, respectively. According to economic indicators, the highest conditional net profit (21,1 thousand UAH per hectare) and the level of profitability (305%) provided willow rod on the scheme of planting 0,9 x 0,7 m and cleaning in the form of chips every three years.

Nonuse of Forest Residues is Impermissible Overlook for the Country with Limited Natural Resources

In human history forests always satisfied different needs of people like: food, energy, medicine plants, wood materials, fodder. From 20th century wood energy gradually was substituted by fossil fuel. But wood still remained irreplaceable resource for construction, furniture, paper industry. At the same time many new wood products have been developed from wood and agriculture residues, so called engineered wood, like: plywood, chipboards, fiberboards, MDF, etc. Bio-economy today uses biomass for manufacturing bio-based chemicals, plastics, pharmaceutical products as well as, residues for generating bio-energy. Nowadays, when the fossil fuel age declines due to its exhaustible character biomass regains a new importance. Biomass currently is the dominating renewable energy source for multiple use. Gradual substitution of fossil fuel by renewable energies instigates rapid growth of all renewable energy carriers like wind, solar, hydro, geo-thermal and bio-energy. It is the best strategy against climate change too.