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The growing concerns for environmental sustainability and the need for eco-friendly practices in the oil and gas industry have sparked the exploration and development of biodegradable drilling fluids. This review highlights the impact of biodegradable waste additives on drilling fluid properties and their cooperation in minimizing the environmental concerns related to drilling fluid disposals. The examined properties include plastic viscosity (PV), yield point (YP), mud weight (MW), fluid loss, and gel strength. The highest rate of PV (63 cP) and YP (109 lb/100 ft 2 ) was attained by using 4% mandarin peel powder (MPP) while using 3% medium broad bean peel powder (MBBPP) and 0.3% prosopis farcta (PF) showed the lowest PV (4 cP) and YP (5 lb/100 ft 2 ), respectively. Also, the viscosity changed as the particle sizes were changed using wheat nano-biopolymer at 0.5, 1, and 2%. Besides, the base sample had a linear relationship between shear rate and shear stress. However, in the presence of biodegradable particles, the viscosity decreased by increasing the shear rate. In addition, PV and YP were increased using wheat nano-biopolymer, while fluid loss and mud cake thickness were reduced. Further, the highest YP (i.e., 19 Pa) was attained by applying 50% Fe 3 O 4 nanoparticles derived from olive leaves. In comparison, the lowest mud cake thickness is observed by 1% (i.e., 1.81 mm), and the lowest filtration loss was 46.6% at the same concentration. The findings indicated that biodegradable waste additives provide an eco-friendly and cost-effective solution for improving the performance of oil- and water-based drilling fluid properties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The importance and interest in the efficient use and valorization of agro-industrial residues and by-products have grown due to environmental problems associated with improper disposal. Biotechnological production processes, including microbial biosurfactant production, represent a sustainable way to utilize agro-industrial residues and by-products, which are applied as substrates in these processes. Biosurfactants produced by microorganisms using renewable resources are a viable alternative to traditional petrochemical surfactants and have several potential uses in a wide range of industrial sectors due to their minimal ecotoxicity, easy biodegradability, and moderate production conditions. The common applications of biosurfactants, besides in food industry as food additives and preservatives, are in agriculture, environmental protection, the cosmetics and pharmaceutical industry, wastewater treatment, the petroleum industry, etc. This review aims to summarize the comprehensive scientific research related to the use of various agro-industrial residues and by-products in the microbial production of biosurfactants, as well as to emphasize the present state and the importance of their sustainable production. Additionally, based on the available biosurfactant market analysis datasets and research studies, the current situation in science and industry and the future perspectives of microbial biosurfactant production have been discussed.

In recent years, food waste has been a global concern that contributes to climate change. To deal with the rising impacts of climate change, in Hong Kong, food waste is converted into electricity in the framework of low-carbon approach. This work provides an overview of the conversion of food waste into electricity to achieve carbon neutrality. The production of methane and electricity from waste-to-energy (WTE) conversion are determined. Potential income from its sale and environmental benefits are also assessed quantitatively and qualitatively. It was found that the electricity generation from the food waste could reach 4.33 × 10 9 kWh annually, avoiding equivalent electricity charge worth USD 3.46 × 10 9 annually (based on US' 8/kWh). An equivalent CO 2 mitigation of 9.9 × 10 8  kg annually was attained. The revenue from its electricity sale in market was USD 1.44×10 9 in the 1 st year and USD 4.24 ×10 9 in the 15 th year, respectively, according to the projected CH 4 and electricity generation. The modelling study indicated that the electricity production is 0.8 kWh/kg of landfilled waste. The food waste could produce electricity as low as US' 8 per kW ∙ h. In spite of its promising results, there are techno-economic bottlenecks in commercial scale production and its application at comparable costs to conventional fossil fuels. Issues such as high GHG emissions and high production costs have been determined to be resolved later. Overall, this work not only leads to GHG avoidance, but also diversifies energy supply in providing power for homes in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Recovery and recycling of municipal solid waste biodegradable fraction (50-55%) are essential for attaining sustainability and a circular economy. Among organic waste treatment methods, composting is used to recycle organic fractions of waste. However, only 10-12% of municipal solid waste is utilized for composting treatment due to a lack of segregation practices and process challenges, including long process periods, odorous and greenhouse gas emissions, nitrogen loss, and low compost quality, which hinders large-scale practice. The current review paper discusses the challenges of composting treatment and its possible solutions. Various strategies were explored to address these challenges, such as utilizing microbial inoculum, additives, and optimization of physicochemical parameters. It also emphasizes the application of metagenomics for exploring key species. The knowledge about the microbial community and biochemical pathways (genome mining) can be exploited for the improvement of treatment efficiency., Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01087-4., Competing Interests: Conflict of interestThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© Association of Microbiologists of India 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Biochars produced during biodegradable waste pyrolysis are products with a wide range of environmental applications. The effect of impact biochars depends on their properties which determine the course of specific processes. The main aim of the study was to investigate the effect of pyrolysis temperature on selected properties of biochar produced from various plant wastes (beech wood chips, walnut shells, wheat-rye straw), the valorization of which is of key importance for the implementation of the circular economy. Biochars were produced at temperatures of: 400 °C, 500 °C, 600 °C and 700 °C in a nitrogen atmosphere. An increase in the pyrolysis temperature caused a drop in the biochar production yield. As the temperature increased, higher carbon content and lower hydrogen content could be seen in the products obtained. An increase in the pH and total organic carbon (TOC) values also found. The influence of temperature on ash content, observed in the case of BWS (biochar from walnut shell) and BWRS (biochar from wheat and rye straw), did not occur in the case of BWC (biochar from beech wood chips). Another parameter that demonstrated a growing tendency with increasing temperature was the BET specific surface area (except for biochars from wheat and rye straw). An increase in pyrolysis temperature caused a decrease in the diversity and density of the surface functional groups of biochars. The influence of the type of precursor used in the production of biochar on the presence of surface functional groups was demonstrated. The presence of intense stretching vibrations of C-O bonds, having a potential impact on the sorption capacity of biochars, was determined in the FTIR spectra of BWC600 and BWC700 biochars, this feature, combined with the large BET surface area, may affect the sorption potential of these biochars. The presence of this type of high-intensity vibrations was also observed in the spectra of biochar BWRS600 and BWRS700. This can compensate for the low BET surface value and play an important role when using these biochars in sorption processes for organic and inorganic compounds.

In order to transition from a linear to a circular economy in the organic waste management sector, more of the elements in waste need to be recycled. Use of black soldier fly (Hermetia illucens L.; Diptera: Stratiomyidae) larvae (BSFL) for organic waste treatment has potential to harvest more complex molecules than conventional methods. Many organic waste substrates have high water content (>80%), but the impact on BSFL treatment efficiency of substrate water contents >80% is not known. This study evaluated the impact of high water content food waste on BSFL composting efficiency in terms of waste-to-biomass conversion ratio, material reduction, larval survival and the ventilation required for enabling dry separation of larvae from residue. In total, six water contents ranging from 76% to 97.5% were evaluated in two experimental trials. It was found that increasing water content reduced biomass conversion ratio and survival rate of the larvae, from 33.4% of volatile solids (VS) and 97.2% survival in 76% water to 17.5% of VS and 19.3% survival in 97.5% water. Furthermore, we found that the ventilation requirement for achieving dry separation of larvae from residue could be modelled by estimating the amount of water that would need to be removed, taking into account the water bound in the larvae, and knowing the specifics of the ventilation set-up of the modelled system. The findings could have implications on the waste management sector interested in implementing BSFL treatment, as the findings demonstrate that it is possible to treat wet substrates (such as fruit and vegetable wastes) without any pre-treatment other than grinding and attain an adequately dry residue for enabling dry separation of the larvae from the residue., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Waste composting is becoming a key element of integrated waste management. Composting has a number of advantages, including economic benefits, improvement of soil properties through the use of compost, reduction in the use of chemical fertilisers, and minimization of environmental pollution. Composting on a landfill surface appears to be an economical solution that can help close the waste loop and material cycle. In this study, a composting plant located on a landfill surface was analysed. The main objective of the research was to identify the species of plants growing in the organic fraction of municipal solid waste in temporary storage, in the composting plant, and in maturing compost located in a reclaimed plot at the landfill site. During monitoring, 88 plant species were identified altogether. It was observed that compost can become a source of weed infestation. To control the presence of weeds in the compost, basic principles of composting are to be followed to reduce the quantity of weed seeds. The thermophilic phase must occur to reduce the viability of seeds in the input materials and sufficient moisture must be ensured during the composting process. When these principles are strictly observed and the stored compost is maintained without vegetation, the supply of seeds in the compost will be low, and the undesirable spread of plant species to adjacent areas will be controlled. The results showed that the use of the obtained compost did not result in the propagation of weed species. This study demonstrates that composting on a reclaimed landfill offers various advantages such as a closed waste management cycle, coverage of the active landfill body, and fertilisation of the reclaimed part of the landfill., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In the professional literature there is no information on the efficiency of waste treatment in MBT (mechanical-biological waste treatment) systems in Poland. This knowledge is currently particularly important as it will decide on the role of the MBT system in the new reality of the circular economy, and consequently on the direction and necessary scope of modernization of these systems. The article presents a series of technical and technological indicators designated for one of the recently commissioned MBT plants against the background of minimum, maximum and average values of these parameters set for 20 systems with various MBTs covered by the research as part of the review of technological solutions used in Poland, made in 2015. For the system in Marszów, respectively in 2017 and 2018, the average value of the ratio of underscreen to overscreen fraction was 1.4; the losses of mass in the biological treatment process amounted to 28.7 and 29.4%; energy demand - 46.6 and 44.3 kWh/Mg; the aeration index - 16.7 m 3 /(Mg h); the average waste recycling rate - 15.2 and 17.3%; the share of fuel fraction recovery - 11.6 and 16,6% and the share of waste sent to landfill - 33.2 and 32.3%., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Waste composition and characteristics are determinative in selecting technological alternatives to develop waste management strategies that can meet legislative requirements. The aim of this study is to identify the major factors influencing the municipal solid waste (MSW) composition and the properties of its biodegradable fraction in İzmir city, Turkey., Methods: MSW composition was determined in samples collected from different income level areas of the city. Water and organic matter contents, calorific value, and the total chlorine levels in seven biodegradable waste (Bio-MSW) size fractions (between >120 mm and > 10 mm) and in the fine fraction (<10 mm) were analyzed. The data on waste components and Bio-MSW properties were statistically investigated., Results: The average shares of biodegradables and recyclables in MSW were found as 50.2 and 40.3%, respectively. The organic matter content of Bio-MSW increased with waste size ( r  = 0.313, p  < 0.05) and its calorific value were in the range of 2310-3686 kcal/kg. A link between the plastics' share in MSW and the Bio-MSW chlorine levels was recognized (r: 0.666, p  < 0.1). PCA analysis identified the main factors degrading the Bio-MSW quality as the cross contamination due to the mixed collection (30.8%), compaction applied in waste trucks (27.5%), and the inert broken materials trapped in larger fractions (21.3%)., Conclusion: Strong negative impact of mixed collection on Bio-MSW quality indicated that implementation of source separated collection of MSW is crucial for Izmir city in order to develop an integrated waste management system that meets the legal requirements by means of end product quality., Competing Interests: Compliance with ethical standardsThe authors declare that they have no conflict of interest.

Within the UK implementation of the European Union Landfill Directive (1999) has led to the diversion of biodegradable waste (BW) from municipal solid wastes away from landfills. It has been widely anticipated, but thus far not verified, that the diversion of BW and consequent reduction in BW reaching landfill would lead to a change in the degradation processes occurring within landfills and that this would be reflected in an altered evolution in leachate chemistry compared to pre-Directive landfills. This paper provides evidence based on leachate chemistry from two operational landfills together with calculations of the reduced BW content, that demonstrate the acetogenic phase that characterised pre-Directive landfill leachates is missing and is now more typical of methanogenic phase leachate. The paper demonstrates how data from national datasets and detailed landfill records can be used to constrain likely and upper estimates of the amount of BW going into post-Directive landfills, and the observed change in the evolution of leachate chemistry which has resulted from a decrease in BW content from typical values of BW (pre-Landfill Directive) of 22% to an inferred 12% in the case-study landfills. Data provided here add to the growing literature that estimates the amount of BW in recent post-Directive landfills which importantly allow the quantitative linkage between a decrease in landfilled BW and observed changes in leachate chemistry to be established such that future landfill operators can increase confidence in the effect of Directive implementation on landfill operational parameters.

Food waste can be an environmental and economic problem if not managed properly but it can meet various demands of a country if it is considered as a resource. The purpose of this report is to review the existing state of the field in Turkey and identify the potential of food waste as a resource. Food loss and waste (FLW) was examined throughout the food supply chain (FSC) and quantified using the FAO model. Edible FLW was estimated to be approximately 26milliontons/year. The amount of biodegradable waste was estimated based on waste statistics and research conducted on household food waste in Turkey. The total amount of biodegradable waste was found to be approximately 20milliontons/year, where more than 8.6milliontons/year of this waste is FLW from distribution and consumption in the FSC. Options for the end-of-life management of biodegradable wastes are also discussed in this review article., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Accurate prediction of the quantity of household solid waste generation is very much essential for effective management of municipal solid waste (MSW). In actual practice, modelling methods are often found useful for precise prediction of MSW generation rate. In this study, two models have been proposed that established the relationships between the household solid waste generation rate and the socioeconomic parameters, such as household size, total family income, education, occupation and fuel used in the kitchen. Multiple linear regression technique was applied to develop the two models, one for the prediction of biodegradable MSW generation rate and the other for non-biodegradable MSW generation rate for individual households of the city Dhanbad, India. The results of the two models showed that the coefficient of determinations (R 2 ) were 0.782 for biodegradable waste generation rate and 0.676 for non-biodegradable waste generation rate using the selected independent variables. The accuracy tests of the developed models showed convincing results, as the predicted values were very close to the observed values. Validation of the developed models with a new set of data indicated a good fit for actual prediction purpose with predicted R 2 values of 0.76 and 0.64 for biodegradable and non-biodegradable MSW generation rate respectively., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Business opportunities in the household waste sector in emerging economies still evolve around the activities of bulk collection and tipping with an open material balance. This research, conducted in Brazil, pursued the objective of shifting opportunities from tipping to reverse logistics in order to close the balance. To do this, it illustrated how specific knowledge of sorted waste composition and reverse logistics operations can be used to determine realistic temporal and quantitative landfill diversion targets in an emerging economy context. Experimentation constructed and confirmed the recycling trilogy that consists of source separation, collection infrastructure and reverse logistics. The study on source separation demonstrated the vital difference between raw and sorted waste compositions. Raw waste contained 70% biodegradable and 30% inert matter. Source separation produced 47% biodegradable, 20% inert and 33% mixed material. The study on collection infrastructure developed the necessary receiving facilities. The study on reverse logistics identified private operators capable of collecting and processing all separated inert items. Recycling activities for biodegradable material were scarce and erratic. Only farmers would take the material as animal feed. No composting initiatives existed. The management challenge was identified as stimulating these activities in order to complete the trilogy and divert the 47% source-separated biodegradable discards from the landfills., (© The Author(s) 2014.)