Jan Mareček

The Role of Mineral Phases in the Biogas Production Technology

Abstract In the field of electric power industry, renewable energy sources, fertilisers, reclamation, and waste management, biomass is widely studied and used. Minerals are present in every step of biogas transformation, but their forms, occurrence, and composition have not been studied yet. However, there is no comprehensive study research that would address the presence of mineral phases in the process of biogas production. This aim of the study is determination of the amount and composition of the mineral phases present in fermentation residues resulting from different production technologies. Digestate mineral composition was analysed using 46 samples from agricultural biogas plants and university testing biogas reactor. The majority of samples contained the amorphous phase. Minority phases consisted of quartz, albite, orthoclase, muscovite, and amphibole. Opal-CT was found in eleven samples (1.26 to 12.1% wt.). The elements present in gas-liquid fluids or in liquids, gases and aerosols within the biogas technology system may create mineral phases, namely the amorphous phase or the crystalline phase under certain conditions. Opal-CT may enter the fermenter as part of plant tissues referred to as phytoliths, or as an unwanted admixture of different origin. It may also originate from the present amorphous SiO2.

Influence of the Combine Harvester Parameter Settings on Harvest Losses

Abstract This paper deals with the relationship between grain yield and grain losses during harvest. Measurements were carried out on a combine harvester with axial harvesting device allowing various adjustments to combine harvester parameter settings, such as rotor speed, gap between separator and rotor, fan speed, holes of the upper and lower sieves. Values of harvest losses in combine harvester with custom settings for the given crops were compared with values of losses obtained by a harvester with manufacturer’s recommended settings. This paper observes the losses in grains of spring barley and winter wheat crops. All the measurements made showed lower grain losses when the combine harvester settings were customized. In general, custom settings provided quantitative losses lower by 0.198% than settings recommended by manufacturer.

VYUŽITÍ TERÉNNÍHO RENTGENOFLUORESCENČNÍHO SPEKTROMETRU PRO ANALÝZU ORGANOMINERÁLNÍCH MATRICÍ

The portable X-ray-fluorescence analyzer (Innov-X Systems, Inc.) is routinely used as screening tool in geochemical and environmental mapping. The applicability in organomineral matrices was not tested yet. The biogas is produced from maize silage, grass silage, beef and pig manure and slurry, sewage sludge, organic wastes from food industries, organic household waste. As the main result the digestate (anaerobic digestion residues) is manufactured. The digestate is used as fertilizer and/or fuel. In the presented study the three reference materials and three samples of the digestate were analyzed 50 times each. RFA analytical conditions for reference material and samples: Innov-X Systems, Inc., Delta, time measurement: 1. beam: energy 1–40 kV, time 140 s.; 2. Beam: energy 2–10 kV, time 140 s., analytical mode: geochem2. Statistical evaluation of the data set allowed comparison among accuracy and reproducibility for organomineral matrices. The results are in good correlation with data from standard elemental analyses. The presented results has proved very good or satisfactory reproducibility for fourteen elements (Al, S, K, Ca, Mn, Fe, Cu, Zn, Sr, Zr, Mo, Ag, Pb, Th ). The results for three elements (Al, S, Fe) in digestates have high reproducibility, for the Ag, Mn, Mo, Sr, Zr, Th have good reproducibility. The portable XRF is suitable for the mineral fraction characterization in the agricultural materials such as composts, digestates and silages.