Opportunities For Recycling Research Articles

Tracing the EoL Tyre Management Chain in Togo with Focus on Implementing a Tyre Recycling Plant

As part of the “Waste2Energy: hybrid energy from waste as a sustainable solution for West-Africa” project, a tyre recycling plant is being constructed in Davié, north of Lomé, Togo. Understanding the tyre management chain is crucial for establishing the plant’s supply chain. This study aimed to highlight the gaps in and the importance of tyre recycling in Togo while assessing the potential of EoL tyres for the implementation of a tyre recycling plant. Togo’s vehicle fleet, predominantly concentrated in Lomé, is rapidly increasing at a rate of 6% per year, reaching an estimated 285,000 vehicles. Due to economic constraints and limited new tyre availability, most vehicle users opt for used tyres, which have a limited lifespan due to poor road conditions. An investigation of EoL tyre quantities and management chains in Togo was carried out. To evaluate the used and end-of-life tyre management chains, both direct observation and interviews with approximately 200 used-tyre dealers were conducted. The study revealed that, on average, drivers replace tyres every 7.4 months, generating between 30,525 t/a and 78,000 t/a of used tyres, 75% of which are replaced due to severe damage or wear. While the used tyre business is well organized, end-of-life tyre treatment is nearly non-existent, often involving dumping, open burning for metal recovery, or use in meat processing, causing environmental and health risks. To address these challenges, an 8 t/hr capacity tyre recycling plant is planned, based on estimated tyre availability and development opportunities for sustainable recycling in Togo.

A DFT-designed neodymium ion-imprinted membrane with fouling resistance and high flux

The rare earth metal neodymium (Nd) is widely used in advanced industries such as hybrid cars and aerospace. Therefore, recovering neodymium from wastewater presents valuable opportunities for secondary recycling. The recovery of Nd3+ from wastewater using ion imprinting technology (IIT) for efficient selective separation holds significant importance. In this study, hydrophilic Nd(III) ion-imprinted membranes, termed Nd(III)–P/P/TIIM, were synthesized using the IIT technique. Nd(III)–P/P/TIIM exhibited efficient and selective separation capabilities for Nd3+ with a remarkable retention rate of 95.68 % and a high water flux reaching up to 636.94 L·m−2·h−1. Additionally, its relative selectivity coefficients for interfering ions (KLa, KEu, KCu) were 3.9, 29.5, and 37.9, respectively. Various analyses, including DFT calculations, HOMO and LUMO calculations, MEP images, and XPS spectroscopy, confirm that the mechanism of selective retention of Nd3+ by Nd(III)–P/P/TIIM in solution is due to Coulombic adsorption between the –COO− anion and Nd3+ as well as an imprint memory effect. Even after undergoing three water-BSA cycles, the membrane maintained a water flux of 357.96 L·m−2·h−1. The antifouling principle of Nd(III)–P/P/TIIM was investigated by XDLVO theory, attributed to the increase of electron donor tension (γ−) and Lewis acid-base interactions (ΔGAB) at the membrane surface. This work provides an insightful guidance for engineering high-performance membranes and has the potential to provide an alternative method for recycling neodymium.

NdFeB Magnets Recycling via High-Pressure Selective Leaching and the Impurities Behaviors

Global concerns about climate change are driving increased demand of electric vehicles for sustainable transportation and turbines in emerging energy solutions, where permanent magnets (PMs) and rare earth elements (REEs) play a critical role. However, global REEs recycling rates are only 3% and 8% for light and heavy REEs, respectively. This work proposes an effective approach to separate the REEs and iron via high-pressure selective leaching by low-concentrated nitric acid from the end-of-life NdFeB magnet and investigates the impurities behavior during the leaching and precipitation steps. The results from the optimized leaching conditions demonstrated over 95% REEs leaching efficiency with less than 0.3% Fe dissolution. Approximately 70% of Al and B were leached as well, while other elements (Co, Ni, Cu) had leaching efficiencies below 40%, leaving a hematite rich residue. Adjusting the pH removes Al and Fe in leachate but minimally affects Cu, Co, and Ni. Na2S addition is more effective against transition metals, but both methods result in around 10% REEs loss. Direct oxalate precipitation is suggested for the obtained leachate, which can yield over 97.5% REEs oxides with approximately 1.0% alumina, which is acceptable for magnet remanufacturing due to the aluminum content commonly found in magnets. The technology developed in this study offers opportunities for closed-loop recycling and remanufacturing of PMs, benefiting the environment, economy, and supply chain security.Graphical

Recyclability Perspectives of the Most Diffused Biobased and Biodegradable Plastic Materials

The present chapter focuses on the recyclability of both renewable and biodegradable plastics, considering the recovery of matter (mechanical or chemical recycling) from the polymeric materials currently most diffused on the market. Biobased and compostable plastics are carbon neutral; thus, they do not contribute significantly to greenhouse gas (GHG) emissions. Nevertheless, recycling can be beneficial because it allows a prolongation of the material life cycle so that carbon is stored for a longer time up to the final composting. The chemical or mechanical recycling option is linked both to the possibility of reprocessing bioplastics without detrimental loss of properties as well as to the capability of selecting homogenous fractions of bioplastics after waste collection. Moreover, the different structural features of biodegradable bioplastics have resulted in different chemical recycling opportunities and also in different behaviors during the reprocessing operations necessary for recycling. All these aspects are discussed systematically in this review, considering biodegradable bioplastics, their blends and composites with natural fibers.

Exploring a lower carbon future: recycling opportunities in a rural public hospital in Queensland, Australia

This case study investigated waste management in a small, rural, Queensland hospital identifying areas where staff could reduce CO2e within the context of what is logistically possible. Phase I captured waste streams and disposal data for 1 May 2022–31 May 23 in a 20-bed Queensland Health hospital and included three audits of the hospital’s pharmaceutical waste bin. Phase II comprised semi-structured interviews with seven staff. Most potentially recyclable waste was being disposed of in the clinical, pharmaceutical, and general waste streams. All participants were interested in recycling more if appropriate bins were accessible in their work and lunch areas and recycling education was provided. Between 1 May 2022 and 31 May 2023, the CO2e were 44.53t, which equates to approximately 48,327 car km. This study identified opportunities for hospital-wide recycling which would reduce CO2e, waste collection fees, and landfill volume. A limitation was the small number of interviewees due to rural workforce shortages and a COVID-19 outbreak.

Assessment and Sustainable Management Strategies for Plastic Waste in Can Tho City, Vietnam: A Circular Economy Approach

This study presents a comprehensive analysis of plastic waste accumulation in both terrestrial and aquatic environments in Can Tho city, Vietnam, a nation with high per capita plastic consumption and significant plastic waste discharge. Focusing on urban residential areas, riverside communities, suburbs, and rural regions, the research investigates the extent and impact of plastic waste in these diverse settings. Additionally, the study examines the accumulation of plastics at barriers, under bridges, and in the Hau River, identifying the predominance of single-use plastics and their environmental implications. The key findings indicate that the plastic waste leakage at land-based-source emission sites is substantial, with waste persisting for extended periods without effective clean-up. The study reveals a significant accumulation of plastics at barriers and bridge bases in aquatic environments, including along the river. The pollution level was observed to be more influenced by the quantity of waste rather than its mass per unit area, emphasizing the need for targeted waste reduction strategies. The study also identifies seven types of plastic, each associated with different sources of accumulation or settlement. This variety presents both challenges and opportunities for waste management and recycling. Significantly, the research underscores the potential of repurposing plastic waste into recycled products, aligning with the circular economy model. This approach not only extends the lifecycle of plastic products but also contributes to reducing plastic waste generation and minimizing the environmental impact. Overall, the findings highlight the urgent need for improved waste management practices in Vietnam, particularly in urban and riverside areas, and advocate for innovative recycling solutions to mitigate the environmental challenges posed by plastic pollution.

Investigation of the self-healing, road performance and cost–benefit effects of an iron tailing/asphalt mixture in pavement

As a solid waste, iron tailings urgently need to be addressed to prevent further environmental and social issues. This study attempted to replace natural limestone filler (LSF) with 20%, 40%, 60% and 80% iron tailing filler (ITF) in an asphalt mixture to improve its microwave self-healing properties. For this purpose, the microscopic appearance and chemical composition of the ITF and LSF were first characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) test, while their microwave heating capacity and electromagnetic loss properties were explored. The microwave thermal behaviors of asphalt mixtures containing different substitution ratios of ITF were analyzed via infrared thermography. The self-healing abilities of the various mixtures were tested by five fracture-healing cycles with three-point bending (3PB) test. In addition, the high-temperature stability, low-temperature crack resistance and water stability of the mixtures were evaluated. Furthermore, the economic and beneficial aspects of the ITF-doped mixtures were assessed by cost–benefit analysis (CBA). The experimental results suggest that an ITF with more metal oxides and better electromagnetic loss characteristics exhibits favorable microwave heating ability. After fifth crack-healing cycle, the healing capacity of the mixtures with 60% and 80% ITF increased by 2.5 and 2.75 times, respectively, compared to that of the mixture without ITF. A total of 40% is the recommended appropriate addition of ITF, which helps to improve or has less impact on the road performance. Additionally, based on the CBA method, the incorporation of more than 60% ITF into an asphalt mixture can provide considerable economic efficiency. As a consequence, the potential use of ITF as an eco-friendly filler in asphalt mixture presents new opportunities for waste recycling and resource conservation while also introducing novel approaches for self-healing pavement.

Leaching Li from mixed cathode materials of spent lithium-ion batteries via carbon thermal reduction.

The use of a carbon thermal reduction roasting method to recover lithium resources from spent lithium-ion batteries (S-LIBs) provides an important opportunity for recycling S-LIBs. The preferential extraction of Li via reduction roasting has been widely studied; however, the extraction of Li from mixed cathode materials has been rarely reported. Herein, we propose a method based on carbon thermal reduction to preferentially extract Li from mixed cathode materials. It was confirmed that there are differences in carbon thermal reduction products at 700 °C-850 °C by the thermodynamic analysis of the carbon thermal reduction process. At the same time, the effects of factors such as roasting temperature, roasting time, and material ratio on Li leaching efficiency were investigated. The Li recovery rate reached 98.86% under the optimal conditions of holding at 750 °C for 4 h with a molar ratio of mixed cathode materials to graphite of 1 : 0.25. Recovered Li2CO3 can be directly used as a lithium source for the regeneration of cathode materials. This study will provide new opportunities for the efficient recycling of spent lithium-ion batteries (S-LIB) mixtures.

(Invited) Development and Scale-up of Membrane Capacitive Deionization (MCDI) for Desalination and Water Reuse

Desalination and water reuse are the key solutions to address global water scarcity. It is important to recognize the water-energy interactions and develop energy-efficient technologies to separate ions from brackish water, seawater and reclaimed wastewater. Most recently, membrane capacitive deionization (MCDI), inspired by energy storage devices (e.g., supercapacitors), is a promising desalination technology with several advantages of energy efficiency (TDS < 4000 ppm), high water recovery, less chemical additive, and environmental friendliness. In MCDI, ions are electrostatically captured within highly porous carbon electrodes through the formation of electrical double layer during the charging step, and then released into the solution by discharging the electrodes. By incorporating ion-exchange membranes (IEMs) in front of each electrode, the desalination performance can be significantly improved, achieving high salt adsorption capacity and charge efficiency. Over the past few years, we have made efforts to scale up the MCDI stacks for commercialization purposes, which are composed of 32 pairs of 400 mm × 200 mm activated carbon electrodes. Note that a stop-flow operation is applied in the discharge process to increase the water recovery (> 75%). A pilot-scale study of an MCDI system was performed to reclaim the secondary effluents from a municipal wastewater treatment plant. In addition, MCDI prototypes offer promising engineering opportunities for water recycling in high-tech industries, including reverse osmosis reject and wet scrubbing. Furthermore, we will discuss the challenges and perspectives for the future of MCDI as a cost-efficient, low-energy approach for desalination and resource recovery.

Reactivity of MSWI-fly ash in Mg-K-phosphate cement

In this study, the behaviour and reactivity of Municipal Solid Waste Incineration Fly Ash (MSWI-FA), introduced in the formulation of magnesium potassium phosphate cement (MKPC), was investigated by considering the waste either as fully inert or reactive. MSWI-FA induced structural and compositional modifications in MKPC as a consequence of dissolution/precipitation processes which involved many MSWI-FA elements (e.g., Ca, Mg, Al, Si, Zn) and led to the formation of mostly amorphous phosphate secondary products. The reaction path has been described in terms of the early fast dissolution of MSWI-FA, with precipitation of very low solubility phases, and subsequent late precipitation due to pH changes and water subtraction during MKPC gelification. The increase in amorphous content peaked to 50 wt.% and it has been related to the improved behaviour with respect to the leaching of heavy metals (reduced by 70-99%), pointing to this cement as an excellent matrix for their chemical stabilization. The obtained MKPC microstructure exhibited better mechanical performance, with an improvement of up to 60% in compressive strength. All in all, the results indicated that the incorporation in MKPC is a viable recycling opportunity for MSWI-FA, although, for an effective cement formulation, its reactivity must be taken into account.

Seaweed Waste in Nusa Dua: An Analysis of Environmental Challenges and Recycling Opportunities

Nusa Dua, a prominent tourist destination, grapples with the multifaceted challenge of seaweed waste accumulation. Through a qualitative approach anchored in extensive literature review and observational data, this study delves into the environmental implications and the latent opportunities that seaweed waste presents. The research reveals significant potential repercussions ranging from ecological disturbances to potential economic downturns linked to reduced tourist appeal. However, it also uncovers various recycling possibilities, including biofuel production and sustainable packaging, offering viable solutions to the problem. This paper underscores the necessity of collaborative action, innovative policies, and community engagement to transform Nusa Dua's seaweed waste challenge from an environmental concern into an opportunity for sustainable development.

Urban nitrogen budgets: Evaluating and comparing the path of nitrogen through cities for improved management

Reactive nitrogen (Nr) released to the environment is a cause of multiple environmental threats. While Nr flows are often only analyzed in an agricultural context, consumption and emission takes place in the urban environment, and opportunities for Nr recycling and effective policy implementation for mitigation often appear in cities. Since little information is available on the bigger picture of Nr flows through the urban environment, these opportunities often remain unexploited. Here we developed a framework to model Nr pathways through urban and surrounding areas, which we applied to four test areas (Beijing and Shijiazhuang (China), Vienna (Austria), and Zielona Góra (Poland)). Using indicators such as recycling rates and Nr surplus, we estimated environmental risks and recycling potentials based on Nr flows and their entry and exit points. Our findings show marked differences between the core and surrounding areas of each city, with the former being a site of Nr consumption with largest flows associated with households, and the latter a site of (agricultural) production with largest flows associated with industry (fertilizers) and urban plants. As a result, Nr transgresses the core areas in a rather linear manner with only 0–5 % being re-used, with inputs from Nr contained in food and fuels and outputs most commonly as non-reactive N2 emissions to the atmosphere from wastewater treatment and combustion processes. While the peri-urban areas show a higher Nr recycling rate (6–14 %), Nr accumulation and emissions from cultivated land pose significant environmental challenges, indicating the need for mitigation measures. We found potential to increase nitrogen use efficiency through improved Nr management on cultivated areas and to increase Nr recycling using urine and sewage sludge as synthetic fertilizer substitutes. Hence our framework for urban nitrogen budgets not only allows for consistent budgeting but helps identify common patterns, potentially harmful flows and Nr recycling potential.

Аналіз поточної ситуації та засобів запобігання продовольчих втрат і харчових відходів в Україні

Reducing food losses and waste is of significant importance in a world where the number of people suffering from hunger is increasing, especially after 2014. Food waste leads to ecological issues, including carbon dioxide emissions that exacerbate global warming, and it can also result in social and economic problems. It is also crucial to consider force majeure circumstances such as the COVID-19 pandemic, Russian invasion, and the declaration of martial law in Ukraine. Studying and adapting the Ukrainian experience in managing food waste during force majeure situations can be beneficial for other countries in reducing and processing food losses and waste globally. This article is an interim outcome of the UUT17 project (Research Project No. 1877-01/17) "Evaluation of opportunities for prevention, reduction, recycling and reuse of FLW in Ukraine".

Multi-sectorial assessment of phosphorus in Ontario, Canada: Mapping flows and analysis of the potential for recovery and reuse

Phosphorus is a key non-renewable element used in multiple economic activities, and notably for food production. It is therefore a critical material whose recovery is gaining interest. This work maps the annual phosphorus flows across Ontario's economic sectors through material flow analysis using open data sources. This information is used to identify potential opportunities for phosphorus recovery and recycling, all while performing an economic assessment to determine the feasibility of phosphorus recovery from different sectors. Up to 86% of phosphorus imports for food production could be covered by recycled phosphorus, with an average recovery cost of 49 CAD/kg of phosphorus. This cost is lower than the estimated economic losses caused by phosphorus releases into the environment, although it is significantly higher than the cost of fossil-based phosphorus products. However, phosphorus recovery costs vary widely for different waste streams, suggesting the need of exploring cooperative approaches for effective phosphorus recovery at regional scale.

Comparative Analysis of Composition and Porosity of the Biogenic Powder Obtained from Wasted Crustacean Exoskeletonsafter Carotenoids Extraction for the Blue Bioeconomy

The recovery and recycling of wasted resources are at the forefront of contemporary global issues. Methods of addressing several different issues may go hand-in-hand with each other, such as linking food waste recycling into bio-based adsorbent materials and wastewater treatment. Crustacean exoskeletons are promising candidates for bio-friendly adsorbents; however, maximizing their efficiency requires the optimization of processing technology. Crustacean meat offers an (often luxury) culinary delicacy, while their waste exoskeletons offer opportunities for smart recycling of the magnesian calcite nanoporous biocomposite. Here, we conduct a structural characterization of the exoskeletons of three crustacean species to assess how the extraction of valuable carotenoids affects prospects for the further valorization of their porous powder. The exoskeleton powder’s composition and morphology were investigated by SEM, Raman spectroscopy, FTIR and XRD. The biomineral component magnesian calcite was recorded both in native and in post-extraction exoskeleton powder. Acetone extraction, however, partially removed organic matter from the exoskeletons, resulting in the porosity of the respective powder increasing significantly from below 10 m2 g−1 in the native powder to over 32 m2 g−1 in post-extraction samples of blue crab and spider crab exoskeletons—while the spiny lobster exoskeleton exhibited low porosity, as measured by the BET method. This new insight could improve exoskeleton processing in the sustainable circular economy and applied blue bioeconomy—most notably for adsorbent materials for pollutants dissolved in water or as ordered, nature-derived nanostructured templates.

Non-dispersive solvent extraction as an alternative for sulfuric acid and copper recycling from membrane distillation concentrate of gold mining wastewater

The wastewater from the pressure oxidation process is a complex stream enriched in sulfuric acid and dissolved metallic species, conventionally treated by neutralization, a technique that does not allow for by-product recovery. Previous studies focused on water recovery from the wastewater by membrane distillation and the concern related to concentrate production after water is recovered is now addressed by using hollow-fiber membrane contactors in non-dispersive solvent extraction processes intended for sulfuric acid and copper recycling. Tris(2-ethylhexyl)amine (TEHA), Aliquat 336, and Lix 84-I were used as extractants, the first two for acid recovery and the latter for copper. It was investigated the contribution of different organic phases flow rate (4–12 cm3/s), organic phase composition (5–15 wt%), and temperature (30–60 °C) on the performance of hollow fiber membrane contactors, with an in-depth disclosure of mass transfer phenomena limiting the extraction efficiency. For both acid and copper recovery, a reduction in viscosity forces prevails over the decrease in inertial forces, improving the flow regime. Even so, the predominant mechanism was the diffusive transport of both solutes into the fluid, across the membrane pores, rather than being carried along by the aqueous phase flow. The acid and copper recovery from membrane distillation concentrate achieved values greater than 91%, which represents an acid stream containing 5.86 g-H2SO4/L and an aqueous copper solution with a concentration of 269.0 mg/L, both at high purity. It was discussed different opportunities for their reuse within the gold ore processing circuit and challenges related to their external commercialization. Preliminary economic analysis suggested that the mineral acid would present slightly higher costs than currently practiced (0.54 US$/kgH2SO4; market prices: 0.03–0.11 US$/kgH2SO4), although the operational costs related to copper were comparable with market prices (11.58 US$/kgCu; market prices: 10.31 US$/kgCu). In a broad context, the opportunity for acid and sulfuric acid recycling has the potential to extend sustainability in the mining sector.

A reusable, impurity-tolerant and noble metal-free catalyst for hydrocracking of waste polyolefins.

One-step conversion of low-purity polyolefins to value-added products without pretreatments represents a great opportunity for chemical recycling of waste plastics. However, additives, contaminants, and heteroatom-linking polymers tend to be incompatible with catalysts that break down polyolefins. Here, we disclose a reusable, noble metal-free and impurity-tolerant bifunctional catalyst, MoSx-Hbeta, for hydroconversion of polyolefins into branched liquid alkanes under mild conditions. The catalyst works for a wide scope of polyolefins, including different kinds of high-molecular weight polyolefins, polyolefins mixed with various heteroatom-linking polymers, contaminated polyolefins, and postconsumer polyolefins with/without cleaning under 250°C and 20 to 30 bar H2 in 6 to 12 hours. A 96% yield of small alkanes was successfully achieved even at a temperature as low as 180°C. These results demonstrate the great potentials of hydroconversion in practical use of waste plastics as a largely untapped carbon feedstock.

The Potential of Replacing Concrete with Sand and Recycled Polycarbonate Composites: Compressive Strength Testing

Concrete contributes 8% of all global carbon emissions, making the need to find substitutes critical for environmental sustainability. Research has indicated the potential for recycled plastics to be used as concrete substitutes. This study extends existing research by investigating the use of polycarbonate (PC) in plastic sand bricks as a mechanical equivalent to concrete. PC has high compressive strength, durability, impact strength, thermal resistivity, clarity, fatigue resistance, and UV resistance. This work provides a method and mold to produce a matrix of sand–plastic sample compositions with dimensions adhering to the ASTM D695 standard for compressive properties of rigid plastic. Compositions of 0% (control), 20%, 30%, 40%, and 50% sand by weight were tested. Samples were tested for compressive strength until yield and stress–strain behaviors were plotted. The results for 100% PC demonstrated an average and maximum compressive strength of 71 MPa and 72 MPa, respectively. The 50% PC and 50% sand composition yielded an average and maximum compressive strength of 71 MPa and 73 MPa, respectively, with an increase in compressive stiffness and transition to shear failure resembling concrete. With a composite density of 1.86 g/cm3 compared to concrete’s average of 2.4 g/cm3, and a compressive strength exceeding commercial concrete demands of 23.3 MPa to 30.2 MPa, this lightweight alternative meets the strength demands of concrete, reduces the need for new construction materials, and provides an additional recycling opportunity for nonbiodegradable waste plastic.

Using Large-Size Three-Dimensional Marine Electromagnetic Data for the Efficient Combined Investigation of Natural Hydrogen and Hydrocarbon Gas Reservoirs: A Geologically Consistent and Process-Oriented Approach with Implications for Carbon Footprint Reduction

The recycling or burial of carbon dioxide in depleted petroleum reservoirs and re-imagining exploration strategies that focus on hydrogen reservoirs (with any associated hydrocarbon gas as the upside potential) are a necessity in today’s environmental and geopolitical climate. Given that geologic hydrogen and hydrocarbon gases may occur in the same or different reservoirs, there will be gains in efficiency when searching for both resources together since they share some commonalities, but there is no geophysical workflow available yet for this purpose. Three-dimensional (3D) marine controlled-source electromagnetic (CSEM) and magnetotelluric (MT) methods provide valuable information on rock-and-fluid variations in the subsurface and can be used to investigate hydrogen and hydrocarbon reservoirs, source rocks, and the migration pathways of contrasting resistivity relative to the host rock. In this paper, a process-oriented CSEM-MT workflow is proposed for the efficient combined investigation of reservoir hydrocarbon and hydrogen within a play-based exploration and production framework that emphasizes carbon footprint reduction. It has the following challenging elements: finding the right basin (and block), selecting the right prospect, drilling the right well, and exploiting the opportunities for sustainability and CO2 recycling or burial in the appropriate reservoirs. Recent methodological developments that integrate 3D CSEM-MT imaging into the appropriate structural constraints to derive the geologically robust models necessary for resolving these challenges and their extension to reservoir monitoring are described. Instructive case studies are revisited, showing how 3D CSEM-MT models facilitate the interpretation of resistivity information in terms of the key elements of geological prospect evaluation (presence of source rocks, migration and charge, reservoir rock, and trap and seal) and understanding how deep geological processes control the distribution and charging of potential hydrocarbon, geothermal, and hydrogen reservoirs. In particular, evidence is provided that deep crustal resistivity imaging can map serpentinized ultramafic rocks (possible source rocks for hydrogen) in offshore northwest Borneo and can be combined with seismic reflection data to map vertical fluid migration pathways and their barrier (or seal), as exemplified by the subhorizontal detachment zones in Eocene shale in the Mexican Ridges fold belt of the southwest of the Gulf of Mexico, raising the possibility of using integrated geophysical methods to map hydrogen kitchens in different terrains. The methodological advancements and new combined investigative workflow provide a way for improved resource mapping and monitoring and, hence, a technology that could play a critical role in helping the world reach net-zero emissions by 2050.

Sustainable assessment and resource recycling opportunities identification for China's pig industry: Integrating environmental, economic and social perspectives

Livestock plays a vital role in the livelihoods and nutritional security of people worldwide and leads to significant environmental challenges. Manure management is a major hurdle for sustainable livestock development and serves as a critical source of natural fertilizer and green energy. Given that pork accounts for the highest meat production and consumption share, this study systematically evaluates China's pig production and main manure resource utilization scenarios from life-cycle environmental, economic, and social perspectives. Results show that China's pig production poses considerable potential environmental risks, primarily in the categories of fossil depletion, freshwater ecotoxicity, particulates formation, global warming, and water depletion. Feed production coupled with traditional manure treatment scenario contributes to 94.4 %–98.4 % of the key environmental impact categories and socioeconomic impact, with 32.0 % to 38.3 % of the economic costs also stemming from feed costs. In the energy utilization scenario, the potential benefits of fossil depletion and global warming categories resulting from the replacement of synthetic fertilizers with manure-based organic fertilizers in the traditional pig manure treatment scenario could be expanded by 89.6 % and 39.2 %, respectively. China's pig production contributed 0.72 % of the national carbon emissions in 2020. Fully utilizing energy potential and organic fertilizer from pig manure would achieve 0.63 % of national carbon reduction potential, as well as an economic benefit of $1.45 × 1012 and a social benefit of $8.89 × 109. Precision feeding technology, rebuilding the spatial connection between pig farms and arable land, and internalizing external costs were recommended to ensure the sustainable development of China's pig industry.