ОПТИМІЗАЦІЯ ЕФЕКТИВНОГО ПРОЦЕСУ ГОРІННЯ МАЛОГАБАРИТНИХ ПАЛИВНИХ РУЛОНІВ ІЗ ЗАЛИШКІВ ПІСЛЯ ЗБИРАННЯ ЛЬОНУ ОЛІЙНОГО

The paper presents the results of research aimed at evaluating the possibility of using selected tree leaf species to produce solid biofuels. The possibility of production of qualitative solid biofuels from urban tree leaves meets the expectations of the municipal sector. Collection of tree leaves in urban areas is very often necessary for road safety reasons, the need to collect biomass rich in dust and pollution as well as biomass infested with pests. The production of solid biofuels from tree leaves allows for effective management of this raw material with energy recovery. The performed research indicates such a possibility, and the obtained ash is used as a soil improver. The conducted research showed that the biomass of leaves of five tree species used in the experiment can be a source of raw materials for production of qualitative biofuels. The obtained pellets were characterized by properties comparable to those of classical wood pellets. The lower heating value of the obtained pellets ranged from 14.5 to 15.5 MJ∙kg−1. Physical properties of the obtained pellets described by bulk density (BD 600–660 kg∙m−3), mechanical durability (DU 90–96%), moisture (Mar 10–12.5%) indicate that these products can be used in existing combustion equipment. Preliminary analysis of the obtained ashes (determination of ash melting point, bulk density) indicates that they should not cause difficulties in ash removal systems from the combustion chamber.

Producing durable and efficient solid biofuels should be an important consideration in Nigeria’s present economy due to the numerous advantages associated with it. It offers the benefit of energy generation, particularly in rural areas, and could potentially replace fossil fuels. However, the adoption and production of solid biofuels at commercial scale in Nigeria is limited by some challenges, including the lack of a developed supply chain structure, inadequate facilities, and air pollution. The present study summarizes the types of solid biofuel production technologies deployed in Nigeria as well as the biomass feedstock utilized in the production of fuel briquettes and pellets. While opportunities exist in the gasification of biomass in Nigeria, direct combustion is a readily applicable fuel conversion process that can be utilized to generate electricity from solid biofuel. The major challenges surrounding the full adoption of solid biofuel production and utilization in Nigeria are highlighted. Among others, promotion of clean energy alternatives, investments and financial incentives, sustainable renewable energy policy and energy transition plan, and legislative backing are identified as factors that could accelerate the commercial production and adoption of solid biofuel in Nigeria.

The article examines the normative monetary valuation of agricultural land in the regions of Ukraine. The dynamics of change of sown areas of the main agricultural crops is analyzed. The directions of the development of agricultural production in the short term are determined. The main components of biomass energy potential in Ukraine are studied – agricultural residues (straw of cereals and rapeseed, by-products of corn and sunflower production) and energy crops (willow, poplar, miscanthus for solid biofuels and corn silage for production). It is determined that in the structure of energy production from biomass in Ukraine, agricultural residues and energy crops occupy the last places, as their potential is used by 0.1-3.0% depending on the type of biomass. The necessity of creating of energy cooperatives in rural areas focused on the production of solid biofuels from crop waste has been proved. The prospects for the development of bioenergy outlined in the «Roadmap for the development of bioenergy until 2050 and the Аction plan until 2025» are studied and the forecast of the development of the energy potential of biomass is made. It is determined that despite a significant number of existing regulations related to the development of biofuels, measures to support biofuel producers include only two instruments: a «green» tariff for electricity produced from renewable energy sources (including biomass / biogas), and stimulating tariff for thermal energy, produced from alternative energy sources (including biomass / biogas). Barriers to the development of biofuels production and possible ways to overcome them have been studied. The need to create bioenergy clusters to stimulate the production of biofuels has been identified. Measures to improve state regulation and support the production of biofuels are summarized. It is proved that at the state level it is necessary to constantly motivate agricultural producers to produce different types of biofuels. The main directions of the strategy of biofuel production development in the conditions of land relations reform are substantiated.

Hydrothermal co-carbonization of sewage sludge and high concentration phenolic wastewater for production of solid biofuel with increased calorific value

Ukraine has a large potential of biomass available for the production of solid, gaseous and liquid biofuels. According to 2021 data, the bioenergy potential is about 25 Mtoe, of which 49% is agricultural residues and 30% is energy crops (in case of growing on 2 mln ha). Of the agriresidues, only sunflower husk is now widely used for energy, while the potential of straw, corn stalks and sunflower stalks is practically untapped for this purpose. For Ukraine, one of the promising directions is priority use of corn stalks for the production of energy and solid biofuels such as briquettes and pellets. Another prospective area is growing energy crops. Ukraine has 3-4 mln ha of unused (marginal) agricultural land, which can be engaged for growing energy crops such as willow, poplar, miscanthus (for solid biofuels) and corn silage for biogas. Growing energy crops as biomass feedstock and its further use for the production of heat and power becomes competitive in light of growing prices of natural gas and issues with providing security of its supply. An important but less-developed sector of Ukraine’s bioenergy is motor biofuels. Having such a big potential of agribiomass, the country could produce bioethanol and biodiesel including the advanced biofuels from lignocellulosic feedstock. It is necessary to create favourable conditions for the development of domestic production of motor biofuels. This may include a reduction in the excise tax, the abolition of compulsory tax bill for the full rate of excise duty when transporting bioethanol, the introduction of an export duty on rapeseed, and some other measures.

The main aim of this paper is to present the design of experiment (DOE) and evaluation methodology for this experimental plan in order to determine the parameters effect of biomass densification process on final solid biofuels quality. One of the recovery possibilities for waste biomass raw materials is production of solid biofuels. Using a variety combination of influencing variables can be improve the final quality of solid biofuels. Raw biomass material variables influence, especially (type of raw material, particle size, moisture content, compression pressure and compression temperature) can be recognized during the production of solid biofuels. Their effect can be seen through the quality indicators; especially mentioned variables significantly influence the mechanical quality indicators of solid biofuels. In this experimental research authors would like to investigate properties and behaviour of wood raw waste biomass during densification. This contribution discusses the analysis and design of experimental process, its individual steps and their subsequent DOE leading to the development of a mathematical model that will describe this process. This paper also presents the research findings regarding the effect of influencing variables on final density of solid biofuels during densification. Aim of the experimental process is to determine the mutual interaction between solid biofuels density and influencing variables during densification. Effect of compression pressure, compression temperature, moisture content and particle size on solid biofuels density from wood sawdust was determined.

ABSTRACTBiomass burning has been identified as an important contributor to the degradation of air quality because of its impact on ozone and particulate matter. One component of the biomass burning inventory, crop residue burning, has been poorly characterized in the National Emissions Inventory (NEI). In the 2011 NEI, wildland fires, prescribed fires, and crop residue burning collectively were the largest source of PM2.5. This paper summarizes our 2014 NEI method to estimate crop residue burning emissions and grass/pasture burning emissions using remote sensing data and field information and literature-based, crop-specific emission factors. We focus on both the postharvest and pre-harvest burning that takes place with bluegrass, corn, cotton, rice, soybeans, sugarcane and wheat. Estimates for 2014 indicate that over the continental United States (CONUS), crop residue burning excluding all areas identified as Pasture/Grass, Grassland Herbaceous, and Pasture/Hay occurred over approximately 1.5 million acres of land and produced 19,600 short tons of PM2.5. For areas identified as Pasture/Grass, Grassland Herbaceous, and Pasture/Hay, biomass burning emissions occurred over approximately 1.6 million acres of land and produced 30,000 short tons of PM2.5. This estimate compares with the 2011 NEI and 2008 NEI as follows: 2008: 49,650 short tons and 2011: 141,180 short tons. Note that in the previous two NEIs rangeland burning was not well defined and so the comparison is not exact. The remote sensing data also provided verification of our existing diurnal profile for crop residue burning emissions used in chemical transport modeling. In addition, the entire database used to estimate this sector of emissions is available on EPA’s Clearinghouse for Inventories and Emission Factors (CHIEF, http://www3.epa.gov/ttn/chief/index.html).Implications: Estimates of crop residue burning and rangeland burning emissions can be improved by using satellite detections. Local information is helpful in distinguishing crop residue and rangeland burning from all other types of fires.

A study was conducted to evaluate the effects of N fertilization, wheat (Triticum aestivum L.) stubble burning, and organic amendments on the density of downy brome (Bromus tectorum L.) seed in soil of a winter wheat-fallow crop rotation. The site was part of a long-term study that has been conducted since 1931 near Pendleton, OR. The study consists of a winter wheat-fallow crop rotation with both a fallow and cropped portion of each treatment present each year. The objective of the original long-term study was to document changes over time in soil physical and chemical properties due to the addition of inorganic and organic sources of N fertilizer, and repeated burning of crop residues. A weed seedbank component was added to this study in 1992. To measure effects on the weed seedbank, soil samples were taken in the fall after winter wheat harvest and after winter wheat planting in the fallow and cropped portions, respectively, from 1992 through 1994. From these samples downy brome seed content was analyzed using a sieving-flotation seed extraction technique. Long-term use of inorganic N fertilizer increased the downy brome seedbank compared with an unfertilized control. Crop residue burning reduced the downy brome seedbank and downy brome plants in the wheat crop. Addition of steer manure or green pea [Pisum sativum (L.) subsp. sativum] vines as an N source did not increase downy brome in the seedbank compared with use of inorganic N fertilizer. This was, perhaps, due to factors such as improved soil health resulting from use of organic soil amendments, or differences in application timing or source of inorganic and organic N fertilizer. The organic form of N from manure may have been applied at a more. opportune time for winter wheat than for downy brome. In addition, plots receiving steer manure produced a higher yielding wheat crop that was likely to be more competitive against downy brome, thereby limiting seed production. Research Question Downy brome is a major constraint to winter wheat production in most production areas of the USA. Wheat production practices such as N fertilization and stubble burning affect downy brome populations in winter wheat. Differences in downy brome populations were observed in a long-term N fertilization and stubble burning experiment and led to a study to determine the effects of inorganic and organic sources of N fertilization, and crop residue burning on downy brome seed in the soil in a dryland winter wheat-fallow crop rotation. Soil samples were taken and downy brome seed content was determined using a sieving-flotation seed extraction technique and counting. The effects of N fertilization rate and source, and crop residue burning on downy brome population dynamics were determined. Literature Summary Practices that affect the distribution, number, or viability of seeds in the seed-bank have a direct impact on subsequent weed plant populations. For example, the primary tillage method used for seedbed preparation directly affects dawny brome seed distribution in the soil and subsequent plant density. Crop rotation has been shown to affect downy brome populations. Nitrogen fertilizer, if improperly timed, can indirectly increase downy brome populations by increasing downy brome growth and, presumably, seed production. Burning of wheat crop residue after harvest has commonly been used as a method of controlling downy brome. One objective of field burning is to destroy downy brome seed produced in the previous wheat crop. Study Description A 3-yr field study was conducted near Pendleton, OR, to document the effects of repeated applications of inorganic and organic sources of fertilizer N, and repeated burning of crop residues on the downy brome seedbank. Soil samples were taken in the fall after winter wheat harvest and after winter wheat planting in the fallow and cropped portions from 1992 through 1994. From these samples, downy brome seed content was analyzed using a sieving-flotation seed extraction technique. Comparisons were made of downy brome seedbank counts between plots receiving repeated N fertilizer rates, organic amendments, or burning of wheat crop residue. Applied Question How much does N fertilization and stubble burning affect downy brome seed numbers in the soil in a winter wheat-fallow crop rotation? From soil samples taken in a winter wheat-fallow crop rotation near Pendleton, OR, the number of downy brome seed in the soil and subsequent downy brome plant density were substantially higher in unburned plots than in burned plots where N fertilizer was applied. When no N fertilizer was applied, few differences occurred in the downy brome seedbank between burned and unburned treatments. Inorganic N fertilization in the absence of burning resulted in substantially increased downy brome seedbank counts. Organic N sources did not increase downy brome seedbank counts. The source and application rate of N fertilizer had a more pronounced effect on the downy brome seedbank than did burning of crop residue.

Synergistic production of nitrogen-rich hydrochar and solid biofuels via co-hydrothermal carbonization of microalgae and macroalgae: When nitrogen circularity matters.

Life cycle assessment and techno-economic analysis for biofuel and biofertilizer recovery as by-products from microalgae

Reduction of CO2 emissions through the co-combustion of lignite with biomass residues: Renewable and non-renewable CO2 per produced megajoule and fuel characterization

Evaluation of Bursera cuneata Schltdl. wood residues for use as densified biofuels

The energy value and economic efficiency of solid biofuels produced from digestate and sawdust

Production of a high-energy solid biofuel from biochar produced from cashew nut shells

Crop residue burning, a prevalent and urgent issue in India, particularly in the IndoGangetic Plains of Haryana, Uttar Pradesh, and Punjab states, has detrimental effects on the climate of the region, agricultural production, and the health of humans, animals, and plants. Despite legal and technological barriers to crop residue burning and the availability of profitable alternatives for farmers, this practice persists in Punjab state. The primary reasons for the ongoing crop residue burning practice are, the amount of surplus crop residue generated, the time constraints of the rice-wheat crop rotation, and the height of stubble left in the field after the mechanical harvesting of rice and wheat crops. One of the proposed alternatives, the incorporation of crop residues directly into the soil before planting the next crop, is considered best. However, this practice is not accepted by farmers of Punjab on a large scale, as it generally decreases crop yields due to Nitrogen (N) immobilization. To counter this constraint, a modified method of incorporation, on-field composting is proposed to manage the rice and wheat crop residues in Punjab. In this method, crop residues will be collected on the field and composted in an on-field composting pit. A valuable product – compost is formed which is broadcasted in the field as an organic fertilizer. This study includes a theoretical analysis of the on-field composting method to manage rice and wheat crop residues. Firstly, crop residue on-field composting costs are assessed and compared with crop residue burning costs to give farmers of Punjab an idea of cost savings by composting crop residues on the field. For this, various input and output costs of the burning method and onfield composting method are evaluated and compared on a per acre basis for managing rice and wheat crop rotation based residues in all districts of Punjab based on the data for three consecutive years (2020, 2021, and 2022). For all three years, in most of the districts of Punjab, the burning practices-related costs per acre were found to be higher than on-field composting costs per acre only if a crop residue burning penalty imposed on a farmer is added as an input cost to the Net Burning Costs per acre. However, without adding crop residue burning penalty cost, the on-field composting costs per acre are higher as the chances of imposing penalties on every farmer who burns crop residues are quite low. Secondly, in this study, the variation of input costs of the on-field composting process, such as labor and machinery costs, along with variation in landholding size (number of acres) with farmers, is also analyzed. For this, four onfield composting models (one-acre, four-acre, eight-acre and sixteen-acre) are studied keeping in mind farmer’s land-holding categories in Punjab. The input cost (labor and machinery costs) per acre for each on-field composting model varies depending on the size of the farmland (number of acres) in each district. In addition, GHG emissions and the social cost of these emissions on crop residue burning are studied as compared to on-field composting of crop residues. As per our assessment, the on-field composting method for managing crop residues is better for both the farmers and the environment of Punjab. The practical implication of this study could be a future research project.