| Abstract [eng] |
Solid biomass fuel such as wood chips and logging residues makes currently the largest share of biomass fuels used for heat generation in district heating plants and provided by variety of suppliers. Ash and moisture contents, as well as calorific value of this fuel may vary considerably depending on composition of the fuel, its preparation technology and storage conditions, as well as seasonality. Knowing the variability of these characteristics is important for at least 2 main reasons. First, it is important in setting the prices of fuel and heat supplied to its consumers, in reconciling balances of produced heat and consumed fuel and eventually for evaluation of the volumes of ash and other harmful emissions. Second, in practice, there is the need for periodic check of biomass supply batch to heat producers, when the characteristics must be examined by taking samples from each lot submitted for analysis. Consequently, the paper provides the results of summarizing the main characteristics of solid biomass fuel, such as moisture and ash content, calorific value, experimentally tested for significant range of samples from two production objects and rather wide time periods between 2018 and 2020, During the period under review (2017-2020), it was found that the moisture content of the fuel varied from 35 %to 45%, the calorific value from 18,400 to 19600 kJ/kg, and the ash content from 0.5% to 4.5%. The calculated relative expanded uncertainty of the moister content measurement was 2,1 %, of calorific value - ± 1,5% and of ash – 1,0%. and measurement uncertainties of those results. |
