Search Results (16)

The topic of environmental pollution by petroleum products is highly relevant due to rapid urbanisation, including industrial development, road infrastructure and fuel distribution. Potential threat areas include refineries, fuel stations, pipelines, warehouses and transshipment bases, as well as sites affected by accidents or fuel spills. This study aimed to determine whether organic and mineral materials could mitigate the effects of diesel oil pollution on the soil’s trace element content. The used materials were compost, bentonite and calcium oxide. Diesel oil pollution had the most pronounced effect on the levels of Cd, Ni, Fe and Co. The levels of the first three elements increased, while the level of Co decreased by 53%. Lower doses of diesel oil (2.5 and 5 cm³ per kg of soil) induced an increase in the levels of the other trace elements, while higher doses caused a reduction, especially in Cr. All materials applied to the soil (compost, bentonite and calcium oxide) reduced the content of Ni, Cr and Fe. Compost and calcium oxide also increased Co accumulation in the soil. Bentonite had the strongest reducing effect on the Ni and Cr contents of the soil, reducing them by 42% and 53%, respectively. Meanwhile, calcium oxide had the strongest reducing effect on Fe and Co accumulation, reducing it by 12% and 31%, respectively. Inverse relationships were recorded for Cd (mainly bentonite), Pb (especially compost), Cu (mainly compost), Mn (mainly bentonite) and Zn (only compost) content in the soil. At the most contaminated site, the application of bentonite reduced the accumulation of Pb, Zn and Mn in the soil, while the application of compost reduced the accumulation of Cd. Applying various materials, particularly bentonite and compost, limits the content of certain trace elements in the soil. This has a positive impact on reducing the effect of minor diesel oil pollution on soil properties and can promote the proper growth of plant biomass. Full article

The main goal of this study is to investigate the possibility of using residual materials (biomass derived from used cooking oils and lignocellulosic biomass from plant waste) on a large scale for producing renewable fuels and, in particular, the best way to collect them. The methodology of Geographic Information Systems (GIS) as well as spatial analysis (SA) techniques were used to investigate the Greek case for this. The data recorded in the geographic database were quantities of waste cooking and household oils as well as quantities of lignocellulosic biomass. The most common global and local indices of spatial autocorrelation were used. Concerning the biomass derived from used cooking oils, it was found that their quantities were important (163.17 million L/year), and these can be used to produce green diesel in the context of the circular economy. Although the dispersion of the used cooking oils was wide, there is no doubt that their concentration in large cities and tourist areas is higher. This finding suggests a collection process that could be carried out mainly in these areas through the development of small autonomous collection units in each neighborhood and central processing plants in small regional units. The investigation of the geographical–spatial distribution of residual lignocellulosic biomass showed the geographical fragmentation and heterogeneity of the distributions. The quantities recorded were significant (4.5 million tons/year) but widely dispersed, such that the cost of collecting and transporting the biomass to central processing plants could be prohibitive. The “geography” of the problem itself suggests solutions of small mobile collection units in every part of the country. The lignocellulosic biomass would be collected and converted in situ into bio-oil by rapid pyrolysis carried out in a tanker vehicle. This would transport the produced bio-oil to the nearest oil refineries for the conversion of bio-oil into biofuels through deoxygenation processes. Full article

With the rapid development of biorefinery technology, the efficient conversion of lignocellulose into high-value platform chemicals is of great significance for enhancing the value of renewable carbon resources. In this study, a hydroxyl-functionalized covalent organic framework (COF), TAPB-DHPA, was synthesized via an in situ method and innovatively applied to the catalytic conversion of xylo-oligosaccharides (XOS) into furfural. The results demonstrated that TAPB-DHPA possesses a large specific surface area, a well-developed porous structure, and excellent thermal stability, with abundant Brønsted acid (B acid) sites, exhibiting outstanding catalytic activity. Under optimal conditions, including a catalyst loading of 0.16 wt%, a reaction temperature of 180 °C, and a reaction time of 3 h, a furfural yield of up to 65.4% was achieved. The high selectivity was primarily attributed to the p-π conjugation effect between the benzene ring and the phenolic hydroxyl group, which enhanced the ionization ability of hydroxyl hydrogen, thereby effectively promoting the hydrolysis of XOS and subsequent dehydration. Furthermore, TAPB-DHPA exhibited excellent recyclability and stability, maintaining a furfural yield of over 59.9% after six cycles. This study provides new insights into the application of functionalized COF in biomass catalytic conversion and contributes to the green transformation of the pulp and paper industry into a biorefinery-based model. Full article

Aquaculture and waste valorization have the potential to show solid achievements toward food security and improvements in the circularity of resources, which are crucial aspects of achieving a sustainable lifestyle in agreeance with Agenda 2030 goals. This study aims to optimize and simplify the decision-making processes for the valorization of marine wastes (natural and from aquaculture) as secondary raw materials to produce high-value-added market goods. However, significant concentrations of pollutants may be present within wastes, compromising overall quality, and social dynamics can hinder their usage further. Goro’s lagoon was chosen as a case study, where the relations between the ecosystem services, a thriving bivalve economy, and social dynamics are deeply rooted and intertwined. Therefore, in the manuscript cost–benefit and foresight analyses are conducted to determine the best usage for algal biomass considering pollution, social acceptance, and profitability. These analyses are virtually conducted on bio-refineries that could be operating in the case study’s area: briefly, for a thirty-year running bio-plant, the CBA indicates the two best alternatives with an income of 5 billion euros (NPV, with a 5% discount rate) for a biofuel-only production facility, and a half for a multiproduct one, leading to the conclusion that the first is the best alternative. The foresight, instead, suggests a more cautious approach by considering external factors such as the environment and local inhabitants. Hence, the main innovation of this work consists of the decision-maker’s holistic enlightenment toward the complexities and the hidden threats bound to this kind of closed-loop efficiency-boosting process, which eventually leads to optimized decision-making processes. Full article

Biomass storage is an essential requirement in the supply chain of bio-refineries and power plants. This research aims to evaluate the influence of long-term outdoor storage (1 year) of baled rockrose (Cistus laurifolius L.) shrub biomass on biofuel’s quality, pre-treatment processes and on combustion emissions in an industrial boiler. The raw material was obtained from different rockrose shrublands in north central Spain. A total of 233 t_WM (tones of wet matter) of biomass were used to produce biofuels (30 mm of milled biomass and Ø 8 mm pellets) in the pre-treatment pilot plants at CEDER-CIEMAT. The combustion tests were conducted in an industrial moving grate boiler with a thermal power of 50 MWth, in a 17 MWe power plant. Outdoor storage improved some biofuel quality parameters, mainly the reduction in ash content, which allowed 30 mm of milled material to be classified as class I1 (ISO 17225-9:2022) and pellets as class I3 (ISO 17225-2-2021). No significant differences were observed in the total specific mass flow and energy consumption in the pre-treatment processes. The combustion tests had similar results, with the emissions being below the limits established in the directive (EU) 2015/2193. The results obtained indicated that the 1-year outdoor storage of rockrose-baled biomass, under Mediterranean conditions, was feasible for its subsequent use as biofuel. Full article

Science and technology are critical for developing novel and sustainable production of food, fuel, and chemicals in a manner that significantly reduces anthropogenic contributions to climate change. Although renewable energy is gradually displacing fossil fuels for grid energy, oil-based transport fuels remain major contributors to global greenhouse gas emissions. Currently, bioethanol and biodiesel can partially replace petroleum, but these renewables are far from perfect in terms of long-term sustainability and the volumetric expansion needed to fully replace oil. Biofuels made in biorefineries using sugars or oils derived from plants grown on prime food-producing land only partly offset CO₂ emissions relative to petroleum and present problems with respect to land-use change. Here, we provide alternative ideas for lignocellulosic biorefineries that coproduce bioethanol, nutritious protein-rich yeast biomass for animal feeds, and carbon-rich solid residuals that represent green coal or sequestered carbon. A concept of how these biorefineries could be linked to renewable power-to-X, where X can be bioethanol, protein, sequestered carbon, or multiple carbon-carbon based synthetic fuels and chemicals, is presented. We also discuss aspects of the present and future roles for microorganisms in lignocellulosic biorefineries and power-to-X bio/chemical refineries. Full article

The high consumption of fossil fuels has significant environmental implications. An alternative to reduce the use of fossil fuels and develop ecological and economic processes is the bio-refinery approach. In the present study, the authors present the production of biodiesel from castor plants through a biorefinery approach. The process includes sub-processes associated with the integral use of castor plants, such as biodiesel production, oil extraction, fertilizer, and solid biomass production. Economic analyses show that producing only biodiesel is not feasible, but economic indicators (NPV, IRR, and profitability index) show it is much more feasible to establish businesses for the valorization of products and subproducts of castor plants, such as biomass densification. The internal rate return for the second scenario (E2) was 568%, whereas, for the first scenario (E1), it was not possible to obtain a return on investment. Full article

The importance of developing efficient and environmentally friendly means of biomass conversion into bioenergy, biofuels, and valuable products is currently high in Poland. Accordingly, herein, two new energy and biofuel units are proposed, namely, POLpec and POLbp, which are used as reference sources for comparing energy consumption and biofuel production in other countries or regions in the world. One POLpec equals 4400 PJ (195.1 Mtoe), reflecting the annual primary energy consumption of Poland in 2020. Meanwhile, one POLbp equals 42 PJ (1.0 Mtoe), referring to the annual production of biofuels in Poland in 2020. Additionally, a new import–export coefficient β is proposed in the current study, which indicates the relationship between the import and export of an energy carrier. More specifically, the potential of biomass and organic waste to be converted into energy, biofuels, and valuable products has been analysed for the rural areas of Poland. Results show that the annual biomass and organic waste potential is approximately 245 PJ (5.9 Mtoe). Finally, the concept of a biomass and organic waste refinery plant is proposed based on the locally available organic materials in rural areas. In particular, two models of biomass refinery plants are defined, namely, the Input/Output and Modular models. A four-module model is presented as a concept for building a refinery plant at the Institute of Technology and Life Sciences—National Research Institute in Poznan, Poland. The four modules include anaerobic digestion, gasification, transesterification, and alcoholic fermentation. The primary reason for combining different biomass conversion technologies is to reduce the cost of biomass products, which, currently, are more expensive than those obtained from oil and natural gas. Full article

Microalgae have attracted significant attention worldwide as one of the most promising feedstock fossil fuel alternatives. However, there are a few challenges for algal fuels to compete with fossil fuels that need to be addressed. Therefore, this study reviews the R&D status of microalgae-based polyculture and biocrude oil production, along with wastewater treatment. Mixotrophic algae are free to some extent from light restrictions using organic matter and have the ability to grow well even in deep water-depth cultivation. It is proposed that integrating the mixotrophic microalgae polyculture and wastewater treatment process is the most promising and harmonizing means to simultaneously increase capacities of microalgae biomass production and wastewater treatment with a low land footprint and high robustness to perturbations. A large amount of mixotrophic algae biomass is harvested, concentrated, and dewatered by combining highly efficient sedimentation through flocculation and energy efficient filtration, which reduce the carbon footprint for algae fuel production and coincide with the subsequent hydrothermal liquefaction (HTL) conversion. HTL products are obtained with a relatively low carbon footprint and separated into biocrude oil, solid, aqueous, and gas fractions. Algae biomass feedstock-based HTL conversion has a high biocrude oil yield and quality available for existing oil refineries; it also has a bioavailability of the recycled nitrogen and phosphorus from the aqueous phase of algae community HTL. The HTL biocrude oil represents higher sustainability than conventional liquid fuels and other biofuels for the combination of greenhouse gas (GHG) and energy return on investment (EROI). Deep water-depth polyculture of mixotrophic microalgae using sewage has a high potential to produce sustainable biocrude oil within the land area of existing sewage treatment plants in Japan to fulfill imported crude oil. Full article

Replacing fossil jet fuel with biojet fuel is an important step towards reducing greenhouse gas (GHG) emissions from aviation. To this end, Sweden has adopted a GHG mandate on jet fuel, complementing those on petrol and diesel. The GHG mandate on jet fuel requires a gradual reduction in the fuel’s GHG emissions to up to 27% by 2030. This paper estimates the potential production of biojet fuel in Sweden for six integrated production pathways and analyzes what they entail with regard to net biomass input and the amount of hydrogen required for upgrading to fuel quality. Integrated production of biofuel intermediates from forestry residues and by-products at combined heat and power plants as well as at the forest industry, followed by upgrading to biojet fuel and other transportation fuels at a petroleum refinery, was assumed in all the pathways. The potential output of bio-based transportation fuels was estimated to 90 PJ/y, including 22 PJ/y of biojet fuel. The results indicate that it will be possible to meet the Swedish GHG mandate for jet fuel for 2030, although it will be difficult to simultaneously achieve the GHG mandates for road transportation fuels. This highlights the importance of pursuing complementary strategies for bio-based fuels. Full article

The present work investigates the uptake of selected trace elements (Cu, Sb, As, Pb, Cd, Zn, Cr, Mn, Ni, V, and Co) from soil and their accumulation in the biomass samples (leaves and flowers) of three selected native plants (namely Oenothera picensis, OP; Sphaeralcea velutina, SV; and Argemone subfusiformis, AS) around an industrial area (Puchuncaví-Ventanas) located in the Puchuncaví valley, in the central region of Chile. Primary emission sources in the area come from a copper refinery, coal-fired power plants, and a set of 14 other different industrial facilities. Trace element measurements in the native plants of this area and the ability to transfer of these pollutants from soil to plants (transfer factor) have been assessed in order to identify the potential use of these plant species for phytoremediation. Preliminary results showed a high concentration of trace elements in the OP, SV, and AS samples. The concentration of these elements in the plants was found to be inversely correlated to the distance of the primary emission sources. Moreover, the high concentrations of trace elements such as Cu, As, Cr and V, upon the toxic limits in the native plant species, suggest the need for continuous monitoring of the region. The OP species was identified as the plant with the highest capacity for trace elements accumulation, which also showed higher accumulation potential in whole aerial parts than in leaves. Transfer factor values suggested that these native plants had phytoremediation potential for the elements Cu, Pb, As, Ni, and Cr. This study provides preliminary baseline information on the trace element compositions of important native plants and soil in the Puchuncaví-Ventanas area for phytoremediation purposes. Full article

A petroleum refinery heavily depends on crude oil as its main feedstock to produce liquid fuels and chemicals. In the long term, this unyielding dependency is threatened by the depletion of the crude oil reserve. However, in the short term, its price highly fluctuates due to various factors, such as regional and global security instability causing additional complexity on refinery production planning. The petroleum refining industries are also drawing criticism and pressure due to their direct and indirect impacts on the environment. The exhaust gas emission of automobiles apart from the industrial and power plant emission has been viewed as the cause of global warming. In this sense, there is a need for a feasible, sustainable, and environmentally friendly generation process of fuels and chemicals. The attention turns to the utilization of biomass as a potential feedstock to produce substitutes for petroleum-derived fuels and building blocks for biochemicals. Biomass is abundant and currently is still low in utilization. The biorefinery, a facility to convert biomass into biofuels and biochemicals, is still lacking in competitiveness to a petroleum refinery. An attractive solution that addresses both is by the integration of bio- and petroleum refineries. In this context, the right decision making in the process selection and technologies can lower the investment and operational costs and assure optimum yield. Process optimization based on mathematical programming has been extensively used to conduct techno-economic and sustainability analysis for bio-, petroleum, and the integration of both refineries. This paper provides insights into the context of crude oil and biomass as potential refinery feedstocks. The current optimization status of either bio- or petroleum refineries and their integration is reviewed with the focus on the methods to solve the multi-objective optimization problems. Internal and external uncertain parameters are important aspects in process optimization. The nature of these uncertain parameters and their representation methods in process optimization are also discussed. Full article

The aim of the study was to explore the possibility of bioremediation of oil refinery wastewaters by the cyanobacterium Synechococcus sp. MK568070, isolated from the Adriatic Sea. The potential of biomass and lipid production was explored upon cultivation on oil refinery wastewater with excess CO₂ after the removal of nutrients. The strain grew well in a wide range of salinities and ammonium concentrations, and was further tested on the wastewater from local oil refinery plant of various N-composition. Growth experiment under optimized conditions was used to analyze the lipid, carbohydrate and protein dynamics. The biomass yield was highly dependent on nutrient source and concentration, salinity and CO₂ addition. Highest biomass yield was 767 mg/L of dry weight. Towards the end of the experiment the decline in carbohydrate to 18.9% is visible, whereas at the same point lipids, in particular saturated fatty acid methyl esters (FAME), started to accumulate within the cells. The content of lipids at the end of the experiment was 21.4%, with the unsaturation index 0.45 providing good biofuel feedstock characteristics. Fourier Transform Infrared (FTIR) spectroscopy analysis demonstrated a high degree of lipid accumulation in respect to proteins, along with the structural changes and biomass accumulation. In addition, the N-removal from the wastewater was >99% efficient. The potential of lipid accumulation, due to the functional photosynthesis even at the minimal cell quota of nutrients, is critical for the usage of excess industrial CO₂ and its industrial transformation to biodiesel. These findings enable further considerations of Synechococcus sp. (MK568070) for the industrial scale biomass production and wastewater remediation. Full article

A detailed literature search was performed to assess the sources, magnitudes and extent of human inhalation exposure to propylene. Exposure evaluations were performed at both the community and occupational levels for those living or working in different environments. The results revealed a multitude of pyrogenic, biogenic and anthropogenic emission sources. Pyrogenic sources, including biomass burning and fossil fuel combustion, appear to be the primary contributors to atmospheric propylene. Despite a very short atmospheric lifetime, measurable levels could be detected in highly remote locations as a result of biogenic release. The indoor/outdoor ratio for propylene has been shown to range from about 2 to 3 in non-smoking homes, which indicates that residential sources may be the largest contributor to the overall exposure for those not occupationally exposed. In homes where smoking takes place, the levels may be up to thirty times higher than non-smoking residences. Atmospheric levels in most rural regions are typically below 2 ppbv, whereas the values in urban levels are much more variable ranging as high as 10 ppbv. Somewhat elevated propylene exposures may also occur in the workplace; especially for firefighters or refinery plant operators who may encounter levels up to about 10 ppmv. Full article

Like many other industries, the sugar and sugar-bioproduct industries are facing important sustainability issues and opportunities. The relatively low and fluctuating profit for sugar, surpluses of sugar, world-wide trend to produce alternative, renewable bio-based fuels and chemicals to those derived from petroleum and reduce greenhouse gases, water- and energy-intensive factories and refineries, and increased consumer demands for sustainably manufactured products are putting pressure on the industries to diversify for sustainability. Sugar crops, including sugar and energy cane (Saccharum officinarum), sugar and energy beets (Beta vulgaris), and sweet sorghum (Sorghum bicolor L. Moench), are excellent, renewable biomass feedstocks because of their availability, their being amongst the plants that give the highest yields of carbohydrates per hectare, and high sugar contents. While much research has been focused on conversion technologies for advanced biofuels and bioproducts, attention is now focused on developing sustainable supply chains of sugar feedstocks for the new, flexible biorefineries, with customers wanting maximum feedstock reliability and quality, while minimizing cost. All biomass from sugar crops are potential feedstocks. The cogeneration of bioelectricity from bagasse and leaf residues is being increasingly manufactured in more countries and, due to the high carbon content of bagasse and leaves, can also be converted into value-added products such as biochar. Sugar crops are superior feedstocks for the production of platform chemicals for the manufacture of a range of end-products, e.g., bioplastics, chemicals, and biomaterials. In several countries and regions, green sustainability criteria are now in place and have to be met to count against national biofuel targets. Processes to convert high-fiber sugar crop biomass into biofuel have been developed but there has only been limited commercialization at the large-scale. Full article