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Effect of Corn Stover Ensiling on Methane Production and Carbon Dioxide Emissions
The biogas and biomethane sectors are crucial for the European Union’s energy transition. One strategy for achieving the EU’s biogas and biomethane targets while reducing the use of agricultural land for energy feedstock production is to use alternative biomass streams. Such a stream includes agricultural residues and by-products. A good example is crop residues after harvesting corn for grain, which are available in large quantities. Due to the fact that they are lignocellulosic biomasses, they require pretreatment. The purpose of this study was to determine the effect of ensiling enhancers on the methane yield of corn stover silages. Corn stover, which was harvested using the same technology, was ensiled in the first variant with an ensiling enhancer preparation based on bacteria of the Lactobacillus plantarum strain (DSM 3676 and DSM 3677) and two strains of propionic acid bacteria (DSM 9676 and DSM 9677), in the second variant with a formulation whose active ingredients were sodium benzoate, propionic acid, and sodium propionite, and in the third with a formulation based on lactic acid bacteria of the strain Lactobacillus plantarum and Lactobacillus Buchneri. The fourth variant was the control; that is, the material was ensiled naturally without the ensiling enhancer preparation. The use of the ensiling enhancer, based on lactic acid bacteria of the Lactobacillus plantarum and Lactobacillus Buchneri strains, reduced carbon dioxide emissions per 1 GJ of silage energy potential in the biogas production process. Specifically, the unique contribution of this research lies in demonstrating the role of ensiling enhancers in improving methane yield and reducing carbon dioxide emissions.
Effect of using deflector in the distributor head of a pneumatic seed drill on the oat seed sowing unevenness
AbstractThis paper presents an innovative solution for a distributor head equipped with a deflector (controlled plate)—intended to change the tilt angle (realignment) of the pneumatic seed drill distributor head cover. We compared two qualitative parameters of seed sowing, coefficient of variation and coefficient of lateral unevenness of seed sowing (δ). Values were obtained on the test stand with an innovative deflector built into the distributor head at three angles of inclination (0°, 5° and 10°). Statistical analyses revealed a significant effect of airflow velocity and deflector angle, which corrects the deviation from the vertical plane of the distributor head, on the uniformity of seed sowing. In addition, regression equations were determined to predict the quality of the seed sowing process. The developed and manufactured innovative distributor head with a deflector that tilts in two planes, designed to improve the distribution evenness of the air stream transporting seed to individual coulters in pneumatic seed drills, received a positive review. The use of a deflector with automatic control of its position angle, correcting the deviation of the distributor head from a vertical plane in pneumatic seed drills improves the uniformity of seeding. Therefore, it is reasonable to use this solution for new pneumatic seed drills and those in use on soils with different relief (undulating surface). Moreover, the solution fits in with modern agricultural manufacturing in accordance with the ideas of precision agriculture.
Effects of Harvest Maturity on the Chemical and Energetic Properties of Corn Stover Biomass Combustion
Over the last decade, there has been increased interest in applying biomass as a raw material for producing biofuels used for thermochemical conversions. Extensive use of biomass could lead to controversial competition for arable land, water, and food; therefore, only waste materials and agricultural by-products and residues should be used to produce biofuels. One suitable by-product of agricultural production is crop residue from the harvest of maize for grain (corn stover). The harvest residues of corn stover consist of four fractions, i.e., husks, leaves, cobs, and stalks, which are structurally and morphologically distinct. The aim of the study was to determine the effect of selected maize cultivars with distinct FAO (Food and Agriculture Organization of the United Nations) earliness classifications on the chemical and energetic properties of their corn cob cores. We determined the chemical properties based on elemental analysis, and the energy properties based on the heat of combustion and calorific values. The content of ash and volatile compounds in the corn cobs were also determined. The results indicated that the heat of combustion of fresh and seasoned corn cob cores ranged from 7.62–10.79 MJ/kg and 16.19–16.53 MJ/kg, respectively. The heat of combustion and calorific value of corn cob cores in the fresh state differed significantly and were strongly correlated with maize cultivars with distinct FAO earliness.
Chemical and Energetical Properties in Methane Fermentation of Morphological Parts of Corn with Different Variety Earliness Standard FAO
Abstract In the last decades, the production of biomass biofuels for thermochemical conversion to replace fossil fuels has attracted increasing attention as it offers significant environmental benefits. A very common way to convert biomass to energy is methane fermentation. The importance of biogas as a source of energy is growing. The use of biomass to biogas production on a large, global scale may lead to controversial competition for arable land, water, and consequently, food. Therefore, only waste materials and agricultural by-products and residues should be used for biogas production. Corn stover is a good example of agricultural residues for biogas production. Therefore, the aim of these studies was to determine the influence of corn variety earliness FAO on the chemical compositions and energy value of morphological parts (fractions) of corn plants. The research material consisted of morphological parts of corn plants: stalks, leaves, husks, and cobs of selected corn cultivars, differing in terms of their FAO earliness: early (FAO 220), medium-early q(FAO 240) and late (FAO 300) varieties. The research included laboratory investigations, elemental analysis, methane fermentation and statistical analyses of results. Based on the results of the study, it was concluded that the FAO earliness of a corn variety had a significant impact on the elemental composition, ash content, biogas, and methane yield in the corn morphological fractions. The highest methane yield of 267.4 m3·Mg−1 TS was found for the cucurbit cover leaves of a variety with an FAO 240 earliness standard.
Application of State Models in a Binary–Temporal Representation for the Prediction and Modelling of Crude Oil Prices
Crude oil prices have a key meaning for the economies of most countries. Their levels shape the general production costs in many sectors. Oil prices are also a base for financial derivatives like CFD contracts, which are popular nowadays. Due to these reasons, the possibility of an effective prediction of the direction of future changes in the price of crude oil is especially significant. Most existing works focus on the analysis of daily closing prices. This kind of approach results, on the one hand, in losing important information about the dynamics of changes during the day. On the other hand, it does not allow for the modelling of short-term price changes that are especially important in cases of financial derivatives having crude oil as their base instrument. The goal of the following article is the analysis of possible applications of a binary–temporal representation in the modelling and construction of effective decision support systems on the crude oil market. The analysis encompasses all researched state models, e.g., those applying mean and trend analysis. Also, the selection of parameters was optimized for Brent crude oil rates. The presented research confirms the high effectiveness of our state modelling system in predicting oil prices on a level that allows for the construction of financially effective investment decision support systems. The obtained results were verified based on proper backtests from different quotation periods. The presented results can be used both in scientific analyses and in the construction of investment support tools for the crude oil market.