Waste Products Research Articles

Production of iron oxide pigments using metallurgical wastes

To produce paints and varnish coatings, there is an opportunity to use a waste of metallurgical production of Yakovlevsky mining and processing complex, Cherepovets, Russia. This waste contains iron oxide as iron oxide pigment. It could be used as an analogue to iron oxide pigment already existing on the market. The authors studied the pigment properties of the waste and the opportunity of using it as a raw material for the synthesis of red iron oxide pigment. The article gives recommendations on the use of the obtained product and shows the opportunity of its application for paint and varnish coatings.

Strategies for Green Supply Chain for Agriculture Equipment Manufacturing Industries: Perspective of Blockchain- IoT Integrated Architecture

In order to protect the environment, manufacturing sectors have begun implementing a green supply chain (GSC) strategy. Governments are enacting increasingly stringent environmental regulations; consequently, industries must reduce the environmental impact of their supply chains. Our research investigates the barriers to implementing a GSC in the agriculture equipment manufacturing industries (AEMI). This research aims to discover and prioritize the barriers that impede the implementation of sustainable supply chain strategies in the AEMI. Through an in-depth literature review, contributions from experts, and empirical analysis, seventy-one barriers are identified across ten categories. The top barrier in each category is determined using the Delphi approach. The Fuzzy Technique for Order of Preference by Similarity to the Ideal Solution (F-TOPSIS) method creates an exhaustive framework that evaluates and ranks these barriers. The top five barriers are the lack of an environmental partnership with buyers and suppliers, the design complexity when reusing or recycling old goods or products, carbon emissions, paint shop emissions, lack of environmental education and training professionals that lack the necessary skills and less manpower available for the greening supply chain. This framework facilitates decision-makers to organize resources and create effective strategies for overcoming identified barriers. In addition, we proposed a blockchain IoT integrated architecture and strategies. This integrated architecture and strategies will help to mitigate all GSC barriers. It also increases the supply chain's transparency, traceability and effectiveness, fostering sustainability practices and reducing environmental impacts. Blockchain and IoT facilitate real-time data collaboration, computerized transactions and the implementation of smart contracts, thereby enhancing cooperation, trust and collaboration among stakeholders. Implementing GSC practices enables manufacturers to reduce waste and increase productivity, thereby saving funds. In addition, adopting sustainable practices improves these industries' reputation and brand image among environmentally conscious customers, investors and other stakeholders.

Formation of an electronic waste management system based on the use of key principles of the best available technologies

Abstract The article substantiates the expediency of the transition of modern industry from a development model based on economic growth to a model built on the principles of the best available technologies (BAT), including the industries responsible for waste management. This is especially true for e-waste management, which is one of the fastest growing categories of waste. Today in Russia, as a transitional stage to the principles of BAT, integrated environmental permits (IEP) issued to enterprises by Russian Environment Ministry are used, which are a document that, in accordance with Art. 31.1 of Federal Law No. 7-FL of January 10, 2002, “is issued for a separate facility that has a negative impact on the environment” and contains a number of requirements and standards enshrined in clause 10 of Article 31.1. Nevertheless, this process is tepid, which is associated both with the lack of development of the issuance procedure itself, and with the non-compliance of the companies’ technological processes with the standards for permissible emissions and discharges. The article formulates the principles that must be observed while issuing an IEP. The procedure for issuing IEPs is considered, its main stages are analyzed. Differences from the similar order in European countries are revealed. The dynamics of issuing IEP for the period from 2019 to 2022, including in the field of waste management, is analyzed. The existing problems in the implementation of waste management activities by regional operators are identified. The analysis and grouping of data on the generation, processing, disposal, neutralization, disposal of production and consumption waste, submitted by Russian companies in the report on the 2-TP form by federal districts, as well as by the category “electronic waste”, was carried out. The structure of these wastes was also analyzed according to hazard class. The increase of the highly hazardous waste mass was found although their share decreased over the specified period. The results obtained made it possible to formulate the most important directions for reforming the system for issuing environmental permits, considering the principles of BAT. Further research will be directed to the formation of a waste management system for the electronics industry at the regional level.

Laboratory assessment of the effect of rice husk, groundnut shells and RHA on the shear, permeability and consolidation of clayey sands

Utilizing waste materials to improve soil properties can result in cost savings and environmental benefits. This study aims to determine the effect of adding agricultural wastes like rice husk ash (RHA), rice husk (RH), and groundnut shells (GS) to clayey sands from Mysore district, India. The study focused on the undrained strength, permeability and volume change behaviour of soils mixed with RHA, RH and GS. The soil samples were mixed with varying amounts of RHA (5%, 10%, 15%, and 20%) and RH-GS (1%, 2%, 3%, 4%, and 5%) and cured for 1, 7, 14 and 21 days. These blended specimens were then used to determine the maximum dry density (MDD), optimum moisture content (OMC) and unconfined compressive strength (UCS). The soil mixture containing 5% RHA and 4% (RH + GS) yielded optimal results in the UCS test. Further tests, including unconsolidated undrained (UU) triaxial, permeability and consolidation tests, were conducted on the parent soil and the soil composite with 5% RHA and 4% (RH + GS). From the undrained test, the strength increased for the soil admixture, with a reduction in the cohesion and an increment in the friction angle, compared to that of the parent soil. The experimental results also showed improvement in the permeability and consolidation characteristics of the blended soil. As RH, GS, and RHA are abundant and considered to be agricultural waste products, using them represents an innovative, sustainable, and cost-effective solution with promising potential for soil improvement.

Multidisciplinary perspectives in Demodex blepharitis: A new view of treatment from clinical, payer, and patient perspectives.

Demodex infestation is the cause of more than two-thirds of all cases of blepharitis in the United States. Although symptoms may include crustiness, redness, or itching of the eyelids, diagnosis can be accomplished through a simple examination of the eyelashes. The presence of a waste product of the Demodex mite, known as collarettes, on the base of the eyelashes is a pathognomonic sign of Demodex blepharitis. Demodex infestation that results in blepharitis may cause blockage and ultimately atrophy of the meibomian glands, worsening dry eye disease. Until recently, management of Demodex blepharitis has been limited by a lack of approved therapy options. Lotilaner ophthalmic solution 0.25%, the first approved therapy for treatment of Demodex blepharitis, has not only been shown to eradicate Demodex mites in one-half to two-thirds of patients following short-term treatment but also demonstrated continued benefits through 1 year of follow-up. In addition to managing Demodex blepharitis, treatment with lotilaner ophthalmic solution 0.25% may aid in the management of dry eye disease and other forms of ocular surface disease caused by complications of Demodex infestation. As a result, it is possible that successful management of Demodex blepharitis may reduce chronic use of health care resources dedicated to managing other chronic ocular conditions. As eye care professionals recognize Demodex infestation as a key mediator of ocular surface disease, increasing diagnostic awareness and addressing this underlying cause of Demodex blepharitis may reduce the need for specialist follow-up care, decrease the need for chronic therapy, and improve patient outcomes. Through routine screening for Demodex infestation and Demodex blepharitis, eye care professionals can now address an underlying factor in ocular surface disease to improve use of health care resources in the community.

8Rs for circular water and sanitation systems: Leveraging circular economy thinking for safe, resilient and inclusive services

To achieve their normative health, environmental and social objectives, water and sanitation services must be safely managed, inclusive and climate resilient. Meeting these imperatives presents a need and opportunity for innovative thinking about water and sanitation service systems. Circular economy concepts are being applied across a multitude of product and service sectors with the aim to facilitate regenerative flows of resources. Given the dependence on water resources, associated climate risks, and the generation of reusable waste products in water and sanitation service delivery, circular economy concepts can be usefully leveraged to drive sustainability outcomes. This article contributes a heuristic in the form of a conceptual framework for applying circular economy concepts in the design and delivery of water and sanitation services in diverse Global South contexts. The framework seeks to drive multiple outcomes relevant to water and sanitation initiatives: safely managed services, social inclusion, and climate resilience. Co-developed by an international research team applying a theoretical multiplicity approach and collaborative sensemaking, the heuristic takes the form of a suite of eight adapted circular economy ‘R strategies’ for water and sanitation. The R strategies were selected and articulated to reflect theory-based principles of circular economy, climate resilience and inclusion. They are intended to prompt thinking and action in pursuit of safely managed, climate resilient, inclusive water and sanitation services that align with the broader sustainability directions that circular economy narratives aspire to. The heuristic offers a conceptually rigorous, practical tool that can support collaborative, deliberative processes to realise the potential benefits of circularity in water and sanitation service systems.

Flash vacuum expansion process promotes increased viability of Limosilactobacillus fermentum J24 in papaya-based beverages under simulated digestion

The processing of papaya generates large amounts of agro-industrial waste, which have become a pollution problem due to the lack of proper management systems. Agro-industrial papaya waste, such as unused peel and pulp, still serves as a reservoir of bioactive compounds, vitamins, and fiber. Therefore, it is important to assess sustainable ways to utilize these waste products. The consumption of antioxidant compounds, fiber and probiotics improves consumer health by preventing or reducing the incidence of diseases. Flash vacuum expansion (FVE) process has been shown to efficiently release antioxidant compounds from vegetable matrices, allowing the use of peel and fruit pulp. This study evaluated the ability of Limosilactobacillus fermentum J24 (isolated from cheese) to ferment a beverage based on papaya puree generated through FVE. It was found that the bacteria exhibited better growth in traditionally generated purees (control), reaching values of 8.5 Log CFU/mL. Before fermentation phenolic compounds and antioxidant capacity was higher in flash-generated puree beverages with values above 20 mg GAE/100 g fresh weight for total phenols and 50 m moles TE/100 g fresh weight for antioxidant capacity. After fermentation, phenolic compounds and antioxidant capacity was higher in control puree beverages. After simulated digestion, higher cell viability was observed in flash puree beverages. FVE process released more intracellular compounds, challenging the bacteria to take metabolic pathways to adapt to a more complex environment, promoting a greater adaptation to the digestive phase, and preserving probiotic potential

Development of a sustainable stabilized macadam road base using steel slag as supplementary cementitious material

As the main waste product of iron and steel industry, steel slag possesses considerable cementitious activity, making it a promising alternative to cement in Cement Stabilized Macadam (CSM). However, CSM was inevitably exposed to groundwater and rainwater when served as the pavement base course, leading to concerns over poor early strength and potential pollutant leakage, which are the main factors that may hinder the widespread utilization of steel slag in CSM base. To address these issues, this study investigated the feasibility of using steel slag powder to produce CSM. Steel Slag Powder-Cement Stabilized Macadam (SSCSM) samples were prepared and the hydration products, microstructure, mechanical properties, water damage resistance and heavy metal ions leaching behavior were investigated. The results show that the nucleation effect of steel slag powder accelerates the early hydration, but the C-S-H produced by hydration is not sufficient to form a stable hydration product network, so the microstructure of SSCSM is looser than that of CSM. The addition of steel slag powder improved the shrinkage performance of SSCSM, and the mechanical properties and heavy metal ion leaching concentration of SSCSM meet the engineering application requirements when the steel slag powder replacement level does not exceed 30 %. It was also found that the addition of steel slag powder promoted the development of pores in SSCSM samples after dry-wet cycles, resulting in the reduction of water damage resistance. Compared with conventional CSM, the use of SSCSM can not only reduce 4 % of raw material cost and 23.5 % of equivalent CO2 emission, but also mitigate the heavy metal ions leaching risk associated with steel slag, making it an effective and sustainable solution for steel slag recycling.

Silk Sericin and Its Effect on Skin Wound Healing: A State of the Art.

Despite the significant progress in wound healing, chronic skin wounds remain a challenge for today's medicine. Due to the growing popularity of natural materials, silk protein-based dressings are gaining more attention in this field. Most studies refer to silk fibroin because sericin has been considered a waste product for years. However, sericin is also worth noting. Sericin-based dressings are mainly studied in cell cultures or animals. Sericin is the dressings' main component or can be included in more complex, advanced biomaterials. Recent studies highlight sericin's important role, noting its biocompatibility, biodegradability, and beneficial effects in skin wound healing, such as antibacterial activity, antioxidant and anti-inflammatory effects, or angiogenic properties. Developing sericin-based biomaterials is often simple, free of toxic by-products, and inexpensive, requiring no highly sophisticated apparatus. As a result, sericin-based dressings can be widely used in wound healing and have low environmental impact. However, the literature in this area is further limited. The following review collects and describes recent studies showing silk sericin's influence on skin wound healing.

The Effect of Adding Minor Actinide Fuel Rods on GFR Reactor in Radiopharmaceutical Waste Production Using OpenMC Program

GFR is a generation IV reactor based on helium gas refrigeration capable of working at very high temperatures. The fast spectrum in this reactor makes it possible to use nitride-based fuel, namely Uranium Plutonium Nitride (UN-PuN). Adding minor actinide (MA) material to the primary fuel, UN-PuN can maximize reactor performance to near critical from the beginning to the end of burn-up. This study aims to analyze the effect of adding MA fuel rods to the heterogeneous core of 5 fuel variations (F1, F2, F3, F4, F5) on the probability of radiopharmaceutical waste production. The method in this research is to place MA fuel rods in this study using four designs based on the highest neutron flux value in one fuel assembly. The results of the neutron flux calculation show that the reactor’s active core’s central region (F1, F2, F3) needs to be added to MA fuel rods so that the resulting flux is more evenly distributed. The calculation of reactor criticality shows that Np fuel rod design 4 and Am fuel rod design 1 have the best keff value (keff ≈ 1) among other designs. The burn-up of MA fuel rods produces a minimal probability of producing Tc99m, Sr89, Y90, Rh105, Ag111, I231, and Sm15 radiopharmaceutical waste, even less than 1 kg.

May Glymphatic Drainage Improve Life Quality in Progressive Multiple Sclerosis Outpatients?

The cerebral fluid-dynamic system plays a critical role in maintaining brain health and function. Recent studies identify the glymphatic system as primarily responsible for removing waste products and toxins from brain tissue. In recent years, we have achieved beneficial improvements in MS patients' symptoms and lifestyle using a specific Fluid Dynamic Intensive MAM (FD-MAM) protocol. We treated 40 outpatients with progressive MS, aged 45-55 years and with EDSS scores from 6 to 9. We applied FD-MAM in 10 daily sessions over two weeks. Before and after glymphatic drainage by FD-MAM, we assessed each patient's clinical status and quality of life using six validated questionnaires. Data from the six validated questionnaires administered to the 40 MS patients show an improvement in 83% of the scores. At the same time, we observed a shift from pathological to physiological values in 50% of the pathological scores after 10 sessions of FD-MAM protocol. This study confirms the positive improvements on life quality in outpatients with progressive multiple sclerosis after one cycle of Fluid Dynamic Intensive MAM (FD-MAM) protocol. Initial follow-up on few patients treated with the FD-MAM protocol suggests that the results persist for six to ten months post-treatment. Future detailed studies, on MS outpatients' larger cohort, are essential to assess the duration of results and its effect on glymphatic system.

Fermentation of Biomass and Residues from Brazilian Agriculture for 2G Bioethanol Production.

Brazil is one of the world's leading producers of staple foods and bioethanol. Lignocellulosic residual sources have been proposed as a promising feedstock for 2G bioethanol and to reduce competition between food and fuels. This work aims to discuss residual biomass from Brazilian agriculture as lignocellulosic feedstock for 2G bioethanol production as bagasse, stalk, stem, and peels, using biorefining concepts to increase ethanol yields. Herein, we focused on biomass chemical characteristics, pretreatment, microorganisms, and optimization of process parameters that define ethanol yields for bench-scale fermentation. Although several techniques, such as carbon capture, linking enzymes to supports, and a consortium of microorganisms, emerge as future alternatives in bioethanol synthesis, these technologies entail necessary optimization efforts before commercial availability. Overcoming these challenges is essential to linking technological innovation to synthesizing environmentally friendly fuels and searching other biomass wastes for 2G bioethanol to increase the biofuel industry's potential. Thus, this work is the first to discuss underutilized lignocellulosic feedstock from other agrifoods beyond sugar cane or corn, such as babassu, tobacco, cassava, orange, cotton, soybean, potatoes, and rice. Residual biomasses combined with optimized pretreatment and mixed fermentation increase hydrolysis efficiency, fermentation, and purification. Therefore, more than a product with a high added value, bioethanol synthesis from Brazilian residual biomass prevents waste production.

Mixed integer programming and multi-objective enhanced differential evolution algorithm for human–robot responsive collaborative disassembly in remanufacturing system

The recycling of waste products is essential for resource reuse. However, turning operation direction causes significant fatigue to operators handling end-of-life (EoL) products, consequently degrading the recycling efficiency. Accordingly, this study employs responsive collaboration robots to aid operators in turning the operation direction of disassembled products. To solve the human-robot responsive collaboration disassembly line balancing problem (HRRC-DLBP), a mixed integer programming (MIP) model is constructed, and a decoding mechanism is designed in this study. Additionally, a multi-objective enhanced differential evolution algorithm (MEDE) in which the decoding mechanism is incorporated is devised and applied to solve the HRRC-DLBP. The MEDE algorithm is validated by comparing its solution results with those of the MIP model. Finally, the MEDE is used to optimise the EoL printer case for the HRRC-DLBP and the disassembly line balancing problem in which the operation direction is turned by humans (H-DLBP). The optimisation results show that the recycling of EoL products is more efficient using the HRRC-DLBP than employing the H-DLBP.

Mass spectrometry-based proteomics for source-level attribution after DNA extraction

Biological traces recovered from crime scenes serve as vital evidence in forensic investigations. While DNA evidence is frequently used to address the sub-source level of the hierarchy of propositions, the biological source of the DNA can be highly probative at the source level. Current body fluid detection methods pose certain limitations, such as reports of false positive results from some of the presumptive and/or confirmatory tests in current use. These tests are also individual tests for the detection of one body fluid, meaning that if the sample is suspected to be a mixture of multiple body fluids, then different tests would need to be conducted to confirm the body fluid(s) present, which may exhaust small amounts of available biological trace. Proteomics applications for the identification of body fluids have been previously explored, and potential biomarkers indicative of body fluids discovered from liquid-chromatography tandem mass spectrometry (LC-MS/MS) methods have been reported. This work focuses on developing a mass spectrometry-based proteomics approach for the identification of body fluids by targeting discriminating peptide biomarkers from the non-DNA component left over after DNA extraction of samples. The non-DNA component is typically a waste product but with unappreciated evidential value. Our methodology for the purification of proteins from the post-DNA extraction waste includes an acetone precipitation and single-pot solid-phase-enhanced sample preparation (SP3) technique, microwave-assisted trypsin digestion, and LC-MS/MS analysis of the resultant peptides. Preliminary results from this proof-of-concept study include a list of potentially discriminating proteins and peptides for blood, saliva, and semen developed from the analysis of post-DNA extraction waste. Our method allows for multiple analytes to be targeted simultaneously from a DNA profiling waste stream and we anticipate that it could eventually be incorporated into standard forensic laboratory workflows.

Sustainable practices in construction: Exposing the Potential of Waste as a Resource.

Abstract This paper examines the critical issues facing the construction and demolition industry in the countries of the European Union, with a particular focus on Germany. It presents strategies for waste management and sustainable development goals in construction sector. The construction industry is responsible for a significant proportion of waste production, which underscores the urgency of addressing the impending waste management crisis. The paper highlights the necessity for the implementation of circular-oriented construction practices that prioritize recycling and the reduction of waste, aiming to improve the efficient use of resources in building design and construction. Using a real non-residential building demolition as a case study, the paper outlines specific steps to determine building materials and document demolition procedures. This study presents a variety of selective demolition strategies, with consideration of end-of-life scenarios for materials, including reuse, recycling, and downcycling. The analysis highlights the complexity of the demolition process, emphasizing the necessity for comprehensive evaluation methodologies. By closing the material cycle and prioritizing reuse and recycling, it is possible to achieve sustainable and long-term value retention of building materials. Additionally, methods such as life cycle assessment and material flow analysis for waste streams are introduced. The environmental impact of the demolition of the “Elementum” office building in Munich was analyzed and the CO2 emissions calculated, in relation to transport distances. Results were presented on the reduction in CO2 emissions due to the elimination of transport to landfill and the associated impact on the Life Cycle Assessment. By considering factors such as resource conservation, energy consumption, greenhouse gas emissions, waste generation and pollution, stakeholders can make informed decisions to mitigate negative environmental impacts.

Genetic and phenotypic validation of whole body fat content measured across production phases of Atlantic salmon using dielectric and near infrared Interactance spectroscopy

Accurate and repeated whole-body fat (WBF) measurements across production phases are important for optimizing feed utilization, reducing production waste, safeguarding fish health, ensuring product quality and improving overall salmon production. However, the chemical extraction (reference) methods for WBF recording, although precise and accurate, are costly, destructive and have limited applicability for repeated measurements on live fish. This study validates two digital phenotyping technologies: Dielectric spectroscopy (DS) and Near-infrared spectroscopy (NIR) against the reference Soxhlet chemical extraction method. DS is a fast and non-destructive commercial fat meter, whereas the specially designed NIR interactance allows deep penetration (up to 10 mm) through the fish skin into the body. Approximately 2800 fish belonging to 35 full sibs fish families were recorded for WBF at mean body weight (BW) of ∼110, 300 and 750 g in parr, pre-smolt and post-smolt phases, respectively. The WBF percentage changed across the studied production phases: with parr having a mean of 11.3 % and coefficient of variation (CV = 11 %), pre-smolt decreasing slightly in both mean 10.9 – 11.1 % and CV (5.5 – 8.8 %) and post-smolt with an increase to 14.9 % and CV (8.5 %). Both methods performed well relative to the reference, with NIR (R2 = 0.77 – 0.91) slightly outperforming the DS (R2 = 0.61 – 0.71). Significantly high genetic estimates for NIR (h2 = 0.57 ± 0.04 – 0.62 ± 0.06) and DS (h2 = 0.38 ± 0.07 – 0.56 ± 0.10) signify the potential use of these digital technologies for improving WBF in future selective breeding. The low genetic correlations (rg = 0.22 ± 0.13 – 0.33 ± 0.14) across fresh and seawater phases raise questions about the generalizability of metabolic, lipid and feed efficiency research conducted in parr and pre-smolt phases in freshwater, to the post-smolt stage in seawater. The study highlighted the unexplored detail of the genetic regulation of WBF as fish undergoes production phases. Overall, these results will add to our understanding of genetic architecture for WBF and pave the way for digital phenotyping technologies to record complex but economically important traits and refine breeding strategies.

ON SOME ISSUES OF IMPROVING LEGISLATION IN THE FIELD OF WASTE MANAGEMENT OF PRODUCTION AND CONSUMPTION

Environmental pollution caused by waste-related activities remains one of the main problems of modern society. Improper waste management has serious consequences for the environment, human health and the economy. It is necessary to strictly comply with legislation, develop effective waste management strategies and raise awareness of environmental responsibility to solve these problems. Legislation on the management of production and consumption waste is regulated by regulatory legal acts, primarily the Constitution of the Republic of Kazakhstan, the Environmental Code of the Republic of Kazakhstan, etc. The article suggests some ways to improve the legislation of the Republic of Kazakhstan in the field of waste management, developed scientifically sound recommendations and proposals for their implementation. In this regard, the authors identified gaps, as well as duplicate, outdated norms, conducted an audit of the conceptual apparatus and assessed the effectiveness of the implementation of the Law. In particular, it is recommended to adopt a special law regulating public relations related to the management of production and consumption waste. A review and analysis of scientific and legal approaches to the management of production and consumption waste has been carried out, on the basis of which it is proposed to update the terminology used within the framework of waste management legislation: «waste», «waste of production», «waste of consumption», «waste of consumption and production». Thus, the relevance of this study is enhanced due to the objective needs of further improving the effectiveness of legislation in the field of waste management, its consistency and consistency.

Replacement of conventional aggregates and fillers with steel slag and palm kernel shell ash in dense-graded asphalt mixtures

Large quantities of steel slag and palm kernel shell ash (PKSA) – waste products from steel production and palm oil milling, respectively – are generated annually in several countries, and their disposal is challenging. Meanwhile, the over-reliance on conventional rock aggregates for asphalt mixture production poses increasing sustainability challenges. This study investigated the potential of entirely replacing granite aggregates with steel slag and PKSA in a dense-graded asphalt mixture. Two sets of asphalt mixtures were prepared; the control mixture contained crushed granite aggregate and hydrated lime, while the other set incorporated steel slag as coarse aggregate and PKSA as fine aggregate and filler. Both mixture types utilized AC-30 viscosity-graded asphalt binder. The properties of the waste materials met the quality standards required for aggregates in asphalt mixture production. Both mixture types were designed according to the Marshall design procedure and were evaluated for durability (Cantabro abrasion loss), fatigue cracking Resistance, rutting Resistance, and moisture damage susceptibility. The Cantabro abrasion loss test indicated that the waste-based mixture was 3% less durable than the control. However, the cracking Resistance of the waste-based mixture was approximately twice that of the control. Even though the rapid rutting test indicated that the control mixture was slightly superior in rutting Resistance, the Marshall quotient suggested otherwise. Both mixture types exhibited similar moisture damage resistance. Overall, the steel slag and PKSA samples have shown high potential to replace virgin granite aggregates and lime in asphalt mixtures fully and are, thus, recommended for field performance evaluation and possible adoption.

The proximate composition of vegetables enriched by incorporation of municipal solid waste into fertilizers and its impacts on environment and human health

The recent over production of municipal solid waste (MSW) poses a significant threat to both the ecosystem and human health. Utilizing MSW for agricultural purposes has emerged as a promising strategy to reduce solid waste disposal while simultaneously increasing soil fertility. To explore this potential solution further, an experiment was designed to assess the impact of varying concentrations of MSW (25%, 50%, and 75%) on the proximate composition of 15 different vegetable species. The experiment, conducted between 2018 and 2019, involved treating soil with different levels of solid waste and analyzing the proximate components, such as crude protein, dry matter, crude fiber, crude fat, and moisture content, in the 15 selected crops. The results indicate that the application of 25% MSW significantly increased the levels of crude protein, crude fiber, dry matter, and fat in Spinacia oleracea, Solanum tuberosum, Solanum melongena, and Abelmoschus esculentus. Conversely, the addition of 75% MSW notably elevated the moisture and ash content in Cucumis sativus. Correlation and scatter matrix analyses were conducted to elucidate the relationships between the protein, fiber, dry matter, ash, and fat contents. Principal component analysis and clustering confirmed the substantial impact of Treatment_1 (25% MSW) and Treatment_3 (75% MSW) on the proximate composition of the aforementioned vegetables, leading to their categorization into distinct groups. Our study highlights the efficacy of using 25% MSW to enhance the proximate composition and nutritional value of vegetables. Nonetheless, further research is warranted to investigate the mineral, antioxidant, vitamin, and heavy metal contents in the soil over an extended period of MSW application.

Assessing the potential of olive mill solid waste as feedstock for methane and volatile fatty acids production via anaerobic bioprocesses

The extensive production of olive mill solid waste (OMSW) from olive oil industry in the Mediterranean basin claims effective treatments and valorization strategies. This study aims to elucidate the potential of anaerobic digestion (AD) and anaerobic fermentation (AF) to convert pre-treated OMSW into biogas (CH4) and volatile fatty acids (VFA), respectively. The two thermal treatment conditions (65 °C and 180 °C) that are being implemented in the industry that manages the OMSW were tested. Comparing the two treatments aims to demonstrate the influence on the AD process of the degree of solubilization and degradation of the metabolites produced from the same substrate. AD of OMSW treated at low-temperature (65 °C) exhibited similar methane yields (195 ± 8 mL CH4/g volatile solid (VS)) to raw OMSW. AD of the solid phase (SP) after high-temperature treatment with acid addition at 180 °C resulted in methane yields comparable to raw OMSW while the liquid phase (LP) exhibited low methane yields (85 ± 10 mL CH4/g VS). Nevertheless, LP/180 °C exhibited the highest VFA bioconversion at 27.6 %, compared to less than 10 % for SP/180 ºC, SP/65 °C, and raw OMSW. The VFA profile showed notable variations with thermal treatment temperatures. Propionic acid dominated at SP/65 °C, while acetic acid became the primary VFA at 180 °C. Furthermore, significant degradation rates of phenolic compounds and furans were observed during the final day of both anaerobic processes. Overall, these findings suggest that AD is more suitable for raw OMSW, treated at low temperature and SP at high temperature, while AF offers a promising alternative for high-temperature-treated LP.