Filters
Development of Digestate for Energy Purposes Using Excess Heat from Biogas Plants
The paper presents an analysis of methods for utilizing digestate for energy purposes from two different biogas plants using different technologies. Biogas plant A used only cattle manure and corn silage as substrates, while biogas plant B used technology based on the utilization of food production waste. The analysis showed differences in the chemical, elemental, and thermogravimetric composition of both types of digestate. An analysis of the energy inputs required to produce fuel from digestate was also performed, along with energy balance calculations. The research and analysis led to the conclusion that both types of digestate are suitable for energy recovery. The possibilities of optimizing the process using excess heat from the biogas plant were also analyzed. In the case of digestate A, the combustion heat of digestate B was 17.20 MJ·kg−1, while for digestate A, it was 14.80 MJ·kg−1. The calorific value of digestate A at 8.79% moisture content was 13.40 MJ·kg−1, while for digestate B at 6.03% moisture content, it was 15.80 MJ·kg−1, respectively.
Properties of paper coated with Prunus serotina (Ehrh.) extract formulation
AbstractBarrier properties are very important in food packaging; the better the properties, the longer the product can stay fresh in the packaging, which prolongs the shelf life of the product. One way of improving barrier properties is to modifying the existing coatings with the addition of metal oxides, nanoparticles, or natural extracts. The aim of the study was to compare the barrier properties between paper coated with starch and paper coated with starch and black cherry extract mix.Prunus serotinaextracts were prepared by ultrasonic extraction in 60°C water. The extracts were then filtrated and evaporated to obtain a constant mass. The reference coatings were prepared by dissolving starch in hot water to obtain a solution of 30%. The experimental coatings were prepared by substituting 10% starch for black cherry extract. Coatings were applied on the paper by laboratory coater in two thicknesses: c.a. 7 and 15 g/m2. The papers were characterised by grammage, coating weight, porosity, and roughness. Barrier properties were tested by following methods: Cobb-Unger, KIT, water vapour transmission rate, and heptane vapour transmission rate. Papers coated with formulations including extract had better barrier properties against oils and waxes, better results in KIT, Cobb-Unger, and heptane vapour transmission rate tests. The results of the water vapour transmission rate test as well as porosity and roughness were the same for papers coated with and without extract addition, they were influenced by the thickness of the coating, not the extract addition. The addition of black cherry extract influenced the barrier properties of the coated paper, and the extract improved the properties against oils and waxes.
Lowland Sedge Meadows as a Potential Source of Macro and Micronutrient Supplementation
From the point of view of farming utilization, investigations on the recognition of the mineral composition of sedges appears important, appropriate and useful. Sedges are often found in many meadow and pasture communities. It is therefore worth paying attention to the mineral content of their tissues and their possible impact on the organisms of farm animals such as pigs. The basic objective of this study was to determine the concentration of selected macro and microelements: phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), silicon (Si), copper (Cu), zinc (Zn), chrome (Cr) and nickel (Ni) in the biomass of seven sedge species, potentially used as fodder, commonly occurring in natural sites in Central Europe. The material was collected twice during one growing season in the Krześniczka (N 52°37′14′ E 14°46′06′)—lubuskie voivodeship. The first harvest was carried out at the beginning of May, during the shooting and earring phase. The collected plant material included stems and leaves. The second harvest—the end of June—was collected at a time when the seedlings were developing flowers and young fruits, and their vegetative organs were developing dynamically. In June, the collected material represented organs in all possible development phases. The collected material was dried at a temperature of 65 °C, ground, and analyzed. The obtained results showed a difference in the content of microelements between the May and June harvest dates in the dry matter of all analyzed sedge species, which differed statistically significantly only in relation to copper. The harvest date had a statistically significant impact on the change in the content of macroelements in the dry matter of all analyzed sedge species and was associated with a decrease in the content of phosphorus, magnesium and calcium, while in the case of silicon, the delay in mowing resulted in an increase in the content of this element.
Bioethanol Production Potential and Other Biomass Energy Properties of Invasive Reynoutria, Solidago, and Spiraea Plants
Conversion of Carbohydrates in Lignocellulosic Biomass after Chemical Pretreatment
The aim of the study was to determine the quantitative and qualitative changes taking place in biomass components actively participating in methane fermentation, i.e., in carbohydrates, as a result of chemical pretreatment. Analyses were conducted on agricultural waste (corn stover, also called corn straw, and corncobs) as materials most commonly used in methane fermentation, as well as poplar wood, a material relatively rarely used in biogas production. Pretreatment with the aim of increasing efficiency of methane fermentation was carried out with the use of acid and alkaline solutions of different concentrations. The effect of pretreatment on carbohydrates was analyzed based on the quantitative and qualitative changes in this component. Due to the structural heterogeneity of carbohydrates, their varied reactivity and fermentability were determined in terms of holocellulose, cellulose, and pentosans. The chemical structure of cellulose was also analyzed. It is shown in this study that chemical pretreatment causes transformations of carbohydrate components, which differ quantitatively and qualitatively in the compared raw materials. It was found that the alkaline treatment caused smaller changes in the percentage shares of the carbohydrate biomass components as compared to the acid treatment. Moreover, it was observed that the compared materials differ in terms of quantitative changes in their chemical composition depending on the composition of the raw material prior to pretreatment. In the case of corn waste subjected to the action of 1 and 3% NaOH, the share of pentosans in the biomass increased. It was established that this is a change with a positive effect on fermentation efficiency. The action of acids and alkalis on the biomass led to similar structural changes in cellulose, which are adverse for the fermentation process.
Project entitled "an innovative product made of shrub willow for the wood industry" financed by Me&S under the "science for society" program
The Impact of the Renovation of Grassland on the Development of Segetal Weeds in Organic Farming
The intensive use or discontinuation of the use of swards can compromise biodiversity, yields, and feed quality; thus, leading to the degradation of permanent grasslands. Various methods of renovation are employed to restore the usability of degraded swards. In the years 2013–2016, a monofactorial field experiment was carried out on the Experimental Farm in Grabów (province of Mazowieckie, Poland). The experiment involved swards being reseeded after ploughing (P) and after disking with a compact harrow (H), with a non-renovated sward as the control treatment. The plots under renovation were reseeded with a lucerne–grass mixture. Both seedbed preparation methods for the renewed sward, ploughing (P) or shallow disking to a depth of 5 cm (H), were found to be effective for increasing sward yields, restricting weed growth, and reducing the number of weeds in the sward. The ploughing-based renovation method (P) had a strongly restrictive effect on biodiversity, as expressed by the H’ function value vis-à-vis the harrow method (H) and the non-renewed control (NR). Dicotyledonous species accounted for 92.3% of the weed population in the studied treatments. Of these, Taraxacum officinale, Achillea milefolium, Capsella bursa-pastoris, and Plantago maior occurred in the highest numbers.
Deepening the understanding and extending the potential of waste biomass temperature treatment using sunflower husk as an example
The Influence of Drying Sewage Sludge with the Addition of Walnut Shells on Changes in the Parameters and Chemical Composition of the Mixture
Correlation between rotational molding process temperature and degradation changes of polyethylene and composites containing coffee spent grounds used as an active filler
Evaluation of Changes in the Chemical Composition of Grasses as a Result of the Methane Fermentation Process and Biogas Production Efficiency
Methane fermentation, which is one of the key processes in biogas production, plays an important role in the conversion of biomass to energy. During this process, changes occur in the chemical composition of organic feedstocks, including the chemical composition of grasses. The assessment of these changes is crucial for the efficiency and productivity of biogas production. The material for this study comprised fully mature grass blades with leaves and inflorescences and was collected from extensively used meadows and pastures, as well as cultivated and set-aside areas in the Wielkopolskie Voivodeship, the communes of Białośliwie and Trzcianka, Poland. The aim of this study was to compare methane fermentation efficiency in nine grass species and identify the biomass component involved in biogas production. The results indicate that the fermentation process, as expected, changed the cellulose content. The lignin content of the grasses before fermentation varied more than the cellulose content. The content of holocellulose (sum of carbohydrate components) in the grasses ranged from 59.77 to 72.93% before fermentation. Methane fermentation significantly reduced the carbohydrate content in the grasses, with a low degree of polymerization. Grassland biomass-based biogas production is a viable alternative to conventional fossil fuels.
Ruderal Habitats: A Source for Biomass and Biogas
The aim of the study was to evaluate the chemical composition and biogas potential of selected ruderal and expansive plant species: Heracleum sosnowskyi, Aegopodium podagraria, Chaerophyllum bulbosum, Acer negundo, and Urtica dioica. Plant material was collected from a 19th-century park in the village of Niegolewo (Greater Poland Voivodship) and analyzed for cellulose, lignin, hemicellulose, extractives, and ash content before and after methane fermentation. Fermentation followed DIN 38 414-S8, and chemical analyses used standardized methods (TAPPI, Seifert, and DIN). Statistical analyses included ANOVA, CVA, and hierarchical clustering. The highest biogas yield was obtained from A. podagraria, which is associated with low lignin and high hemicellulose degradation. The results confirm the potential of ruderal biomass as a diverse source for biogas production.