Environmental Engineering Research Articles

Implementation of sustainability and circular economy aiming for performance in the context of Industry 4.0 projects

This research aims to provide an up-to-date overview of the scientific knowledge produced through publications that associate sustainability, the circular economy, and performance in the context of Industry 4.0 projects. For this purpose, a systematic and bibliometric review was conducted using articles published in the Scopus database from 2013 to 2024. Inclusion and exclusion criteria were defined, resulting in 61 selected articles. The results show that studies focus on the areas of environmental science, business, management, accounting, and engineering. Additionally, they indicate that research on these topics has grown exponentially in recent years, evolving and deepening significantly during this period. This study directly contributes to researchers seeking references, concepts, gaps, and trends in research on these topics, as well as to managers interested in implementing sustainability and the circular economy, ensuring or even enhancing the performance of their companies through disruptive projects that utilize Industry 4.0 technologies.

Risk analysis of route choices for construction and demolition waste disposal planning using geospatial technology.

Construction and demolition waste (C&DW) is increasing at an alarming rate globally. It is estimated that worldwide, C&DW occupies over 17,420,000 km2 of land with an average depth of around 15.25m, amounting to an astonishing 2.7 billion cubic meters of landfill space. The annual generation of C&D debris in India is up to 150 million tons. This study examines the use of geospatial technology to effectively manage C&DW disposal in the legal dumping yards of Chennai. Data were collected on C&DW in Chennai, which has 15 legal dumping sites and two recycling units in Perungudi and Kodungaiyur. Geospatial technology was applied to analyze optimal route planning, considering sources, and C&DW disposal locations, with two scenarios: the stationary container system and the hauled container system. The results suggest that the hauled container system is Chennai's most suitable debris collection method, providing an optimal route with reduced environmental pollution. These findings are helpful for urban planners and environmental engineers, assisting in transforming old urban areas into new smart cities through effective planning and design.

Refinement of a kinetic adsorption model through Artificial Intelligence

The adsorption process involves capturing contaminants at active sites on adsorbent materials. Its economic efficiency and simplicity distinguish it as a preferred option amidst concerns about anthropogenic pollution. Traditional kinetic models present challenges in fitting nonlinear behaviors of porous materials, prompting the exploration of alternative approaches. Machine learning has a wide range of applications in various fields, including environmental engineering. These models possess generalization capabilities and are used as predictive tools, but they can lead to undesired behaviors if the system is complex and the model fails to capture this complexity. A novel methodology is proposed where the calibration of traditional models is studied using a machine learning model for adsorption kinetics, with hexavalent chromium as the adsorbate and activated carbon as the adsorbent. Furthermore, the technique of adding synthetic data to influence the model's capacity is studied, considering whether it leads to overfitting.Traditional models include pseudo first and second order kinetics, while multilayer perceptron is used as the machine learning model. The models obtained through the proposed methodology exhibit significant performance compared to traditional models. Additionally, an improved interpretability in their behavior compared to using only an artificial intelligence model is observed. Calibration ensures physical interpretation while enhancing generalization. The incorporation of synthetic data into the artificial intelligence model resulted in overfitting, subsequent ensemble methods effectively leveraged this, reducing bias related errors. The impact of synthetic data on calibration has demonstrated favorable outcomes.

Enhanced spray-wall interaction model for port fuel injection under medium load conditions

Abstract This study presents an Eulerian-Lagrangian framework for the numerical analysis of spray dynamics, with a focus on droplet movement, spray-wall interactions, and the effects of varying injection parameters associated with port fuel injection (PFI) system. A grid-independent criterion is introduced to optimize mesh analysis for accurate predictions of fuel penetration length. The size distribution of secondary droplets is described using a probability density function, and statistical optimization is subsequently implemented to estimate their mean size. This probabilistic approach enhances the Lagrangian wall film (LWF) model, leading to accurate predictions of the Sauter mean diameter (SMD) at a given radial width ( $$R_\text{{w}}$$ R w ), with results closely matching experimental data. For $$8.0 ~\text {mm} \le R_\text{{w}} \le 24.0 ~\text {mm}$$ 8.0 mm ≤ R w ≤ 24.0 mm , the maximum SMD of 21.67 $$\mu$$ μ m corresponds to $$R_\text{{w}} = 14.0, \text {mm}$$ R w = 14.0 , mm , while the smallest SMD of 12.68 $$\mu$$ μ m is computed for a radial position of $$R_\text{{w}} = 24.0 ~\text {mm}$$ R w = 24.0 mm . The numerical investigation quantifies the role of spray-wall interactions in determining the trajectory of fuel distribution, particularly in the formation of wall films and the relative spatio-temporal diesel concentration (F/A) %. The study explores aspects such as droplet size variations, heat transfer during evaporation, and film behavior under different injection pressures, providing insights into the multiphysical characteristics of spray-wall systems. Near the impingement site ( $$2.0 ~\text {mm} \le R_\text{{w}} \le 4.0 ~\text {mm}$$ 2.0 mm ≤ R w ≤ 4.0 mm ), the plume height ( $$H_\text{{w}}$$ H w ) slightly decreases with an increase in injection pressure. While the CFD methodology in this current work has been primarily developed for automotive engineering sector (PFI engines), it also has potential applications in areas such as additive manufacturing, hydropower engineering, climate science, and environmental engineering.

How Do Driving Factors Affect the Ecological Restoration Degree in Different Basins? A Case Study of Six River Basins in Yunnan, China

Ecological space provides human beings with the material resources and living environment needed for life; it is the basis for human survival and development, and ecological restoration is directly related to the sustainable development of human society. As an important ecological security barrier in China, the ecological restoration of the six river basins in Yunnan Province directly affects the ecological security of surrounding provinces and neighboring countries. At present, there is still a lack of research on the differences in ecological restoration between river basins. Therefore, we assessed the spatiotemporal differences in ecological restoration degree in terms of ecosystem patterns, ecosystem quality, and ecosystem services in Yunnan Province from 2000 to 2019 and explored their influencing factors in the six river basins. The results showed the following: ① The six river basins differed in terms of changes in ecosystem patterns over the 20-year period, with the share of settlement ecosystems increasing in the six river basins. The most pronounced changes in ecosystem patterns occurred in the Nu River Basin. There were also differences in the ecosystem transformation priorities of the six river basins. In addition to this, among the four selected indicators, fractional vegetation cover, net primary productivity, and soil conservation increased, but water retention exhibited a stable deteriorating trend. ② Yunnan Province’s ecological restoration degree as a whole is in a relatively stable state. There is no significant improvement or significant deterioration in the region. The best ecological restoration degree of the six river basins is the Pearl River Basin, with a trend of gradual stabilization improvement, and the worst is the Nu River Basin, with a state of gradual stabilization deterioration. ③ The factors that most influence the Ecological Restoration Index (ERI) of the six river basins are mean annual precipitation change rate, mean annual precipitation, annual mean temperature, ecological engineering, and border index. The precipitation change rate was the most important factor influencing ecological restoration in the six river basins, while the border index was the most important factor influencing the differences in ERI in the six river basins. In the future, ecological restoration measures in the six river basins of Yunnan Province should take into account regional differences, strengthen governmental supervision, and emphasize the impact of border factors on neighboring river basins to promote a balanced degree of ecological restoration in Yunnan Province as a whole.

Company-university intersections through service-learning (SL): a systematic review

The most relevant intersections in society include the relationship between universities and companies for a projection toward the sustainable employability of future graduates. Among the possible intersections, Service-learning (SL) is an educational proposition that may help university students to develop their personal skills, offering them opportunities to learn and practice civic commitment, improving their sense of social and citizen responsibility, and combining academic and community-service learning in a constructed programme where participants train by working on real needs of the environment to optimize and transform the latter. The development of SL programmes in university departments related to technical areas is posing a challenge to faculty members and students, thus it is important to explore this lack of programmes. The main aim of the present study was to identify SL projects and their topics through a systematic review, following the guidelines of the «Preferred Reporting Items for Systematic Reviews and Meta-Analyses» (PRISMA) declaration in the knowledge areas of Architecture, Computer Science, Environmental Engineering, Software Engineering, Computer Engineering, Artificial Intelligence, and Computer Languages and Systems, from the year 2008 to the year 2023. This review includes 128 articles, which were analyzed with ATLAS. Ti 22. The categorical system employed in this work emerged from the topics of the programmes identified in the selected articles, which were verified by experts in the mentioned fields of knowledge. The agreed categories were: accessibility, learning, social groups, courses, devices, infrastructure, games, environment, landscaping, heritage, software and web. The most relevant conclusions highlight that most of the articles refer to theoretical aspects of SL, showing a lack of data on the practical development of SL programmes and their impact on employability. The largest number of SL programmes are developed in the areas of Architecture, Computer Science and Software Engineering. Regarding the topics that are addressed in research, most of the articles refer to social groups, software, learning and accessibility.

A Review of Different Synthesis Approaches to Nanoparticles: Bibliometric Profile

Nanomaterials are currently one of the most popular emerging materials used in different applications such as drug delivery, water treatment, cancer treatment, electronic, food preservations, and production of pesticide. This is due to their interesting features including size-dependent properties, lightweight, biocompatibility, amphiphilicity and biodegradability. They offer wide possibilities for modification and are used in multiple functions with enormous possibilities. Some of them are medically suitable which has opened new opportunities for medical improvement especially for human health. These characteristics also make nanomaterials one of the pioneers in green materials for various needs, especially in environmental engineering and energy sectors. In this review, several synthesis approaches for nanoparticles mainly physical, chemical, and biological have been discussed extensively. Furthermore, bibliometric analysis on the synthesis of nanoparticles was evaluated. About 117,162 publications were considered, of which 92% are journal publications. RSC Advances is the most published outlet on the synthesis of nanoparticles and China has the highest number of researchers engaged in the synthesis of nanoparticles. It was noted in the evaluation of synthesis approach that biological approach is the savest method but with a low yield, while the chemical approach offers a high yield with some level of hazardous effect. Also, the bibliometric analysis revealed that the field of nanotechnology is a trending and hot ground for research.

Bacterial community present in the earthworm’s gut and its role in soil biology and health

Earthworms are known as ecological engineers due to their significant role in enhancing soil health and productivity. Various factors such as temperature, moisture, acidity, pH, sunlight and the availability of organic matter influence their presence in soil. Earthworms exhibit diverse feeding and burrowing behaviors, which lead to crucial ecological processes within terrestrial ecosystems. Their interactions with soil result in the colonization of their gut and surrounding soil by diverse bacterial communities, including key species such as Escherichia coli, Streptomyces, Bacillus and Pseudomonas. These bacteria aid in the digestion of organic and inorganic matter, thereby altering soil physio-chemical properties and enhancing nutrient mineralization, which promotes plant growth. Additionally, earthworms influence nutrient cycling by modifying microbial soil populations and the bacterial communities in their gut and adjacent soil contribute to phytoremediation. This review delves into the types of bacterial populations found in the earthworm’s gut and surrounding soil, elucidating their specific roles and contributions to the terrestrial ecosystem. By understanding these complex interactions, we can better appreciate the vital role earthworms and their associated bacterial communities play in soil biology. This knowledge is essential for developing sustainable agricultural practices and improving soil management strategies, ultimately contributing to healthier and more productive ecosystems.

Preparation of bio‐based polyamide 56/chitosan heavy metal adsorbing nanocomposite fibers by electrospinning

AbstractElectrospinning technology can produce nanofibers with extremely high specific surface area. Bio‐based polyamide 56 (PA56) was combined with chitosan (CS) to prepare PA56/CS composite nanofibers. An in vitro mineralization experiment was conducted to obtain a super hydrophilic composite fiber (PA56/CS‐HAP) with hydroxyapatite deposited on the surface. The adsorption performance of the composite fiber (PA56/CS‐HAP) was evaluated by the adsorbent dosage, solution pH value, and adsorption kinetics. The curves obtained after fitting the kinetics and adsorption isotherms show that the adsorption behavior under pH = 6 is more consistent with the Langmuir adsorption model. The adsorption capacity in a 100 mg L−1 Pb2+ environment is more than 5 times that of 10 mg L−1. Bio‐based PA56/CS static‐spun nanocomposite fibers prepared by in vitro mineralization have great potential in environmental protection, sensors, chemical engineering, and other fields.Highlights PA/CS fibers were prepared by electrospinning. Hydroxyapatite was deposited by in vitro mineralization technique. PA/CS‐HAP fiber achieves super hydrophilic effect. The adsorption capacity of PA/CS‐HAP in 100 mg L−1 Pb(II) reached 27.5 mg g−1. After fitting, the adsorption process is consistent with Langmuir adsorption.

Knowledge, risk perceptions and practices regarding rodents and their associated pathogens: environmental consultants in Chile

BackgroundRodents play essential ecological roles but are also significant reservoirs of zoonotic pathogens, posing risks to humans. Individuals with frequent occupational contact with rodents face an elevated risk of exposure to rodent-borne diseases. This study examines the knowledge, risk perceptions, and practices of Chilean environmental consultants (ECs) concerning rodents and rodent-borne diseases.MethodsA 32-item questionnaire, which focused primarily on biologists, veterinarians, and environmental engineers, was administered. The questionnaire included closed, open-ended, and semi-open-ended questions. Data analyses, performed using R software, involved calculating frequencies and proportions for questions related to knowledge of rodents and rodent-borne diseases, rodent management and handling, biosafety procedures, and training. Additionally, generalized linear models (GLMs) were used to assess knowledge of rodent hosts and diseases, whereas correspondence analysis was used to examine associations between EC characteristics (undergraduate fields of study and years of experience) and responses regarding risk perception and the importance of zoonotic disease training.ResultsCompleted questionnaires were received from 206 ECs. Although the ECs demonstrated a strong awareness of hantavirus cardiopulmonary syndrome, identifying it as a significant rodent-borne threat, knowledge gaps were evident regarding the specific role of certain rodent reservoir species and other rodent-borne diseases in Chile. For example, leptospirosis was well recognized, particularly among veterinarians, whereas emerging zoonoses such as scrub typhus was rarely mentioned. The study also revealed the frequent use of live trapping and direct handling of rodents, resulting in injuries to 32% of the respondents. Despite the widespread use of personal protective equipment, key elements such as respiratory protection and disposable suits were underutilized, and inadequate cleaning practices for traps were reported. Nevertheless, ECs expressed a willingness to participate in zoonotic disease training, underscoring the need for further education.ConclusionsThis study highlights the critical need for ongoing education for ECs on rodent reservoirs, diseases, and biosafety measures to enhance their safety and reduce the risk of zoonotic infections. The findings offer valuable insights for developing strategies aimed at improving awareness and strengthening biosafety practices within this occupational group.

Space Docking Simulation Simulator Overview

Background: Docking mechanism ground simulation test technology has been a significant issue in the aerospace industry. Docking mechanisms must pass various conventional evaluation tests as a class of electromechanical space products and other space products. Due to the unique nature of the working object environment in space engineering, it is very expensive to simultaneously simulate the docking work under space conditions and conduct ground reproduction tests, so the test technology of the docking mechanism must be thoroughly investigated. Objective: This paper reviews patents on aircraft ground docking and space environment simulation systems to provide insights and references to scholars and researchers in spacecraft simulator manufacturing. Methods: The representative patents associated with each simulation equipment for space docking simulators, including mechanical docking dynamics equipment, space-integrated environment simulation experimental equipment, and thermal vacuum experimental equipment, are described by analyzing the structural functions of these simulators and elaborating on their operating principles and characteristics. Results: By describing various types of space simulators, the current direction of space docking simulators can be optimized, and their future development direction is summarized and analyzed. Conclusion: The comprehensive environmental reproduction of the space docking simulator facilitates the examination of actual problems and potential flaws in spacecraft and has a significant effect on the advancement of the space field.

Culturing 3D chitosan/gelatin/nano-hydroxyapatite and bone-derived scaffolds in a dynamic environment enhances osteochondral reconstruction.

Bioreactor can provide a dynamic culture environment for the in vitro construction of osteochondral tissue engineering. They facilitate more efficient exchange of nutrients and provide mechanical and other beneficial stimulation. Previous findings demonstrated that rotary flask (RF) bioreactor, rotary cell culture system (RCCS), or electromagnetic field (EMF) mediated scaffold culture could create a favorable dynamic environment for osteochondral tissue engineering. However, it is still unclear whether there is an optimal bioreactor or if bioreactors under multi-parameter coupling conditions are conducive to osteochondral tissue engineering. Based on this, the application of static T-flask (TF), RF, RCCS, and coupling environment of RCCS and EMF for osteochondral tissue engineering were systematically compared. The results showed that the RCCS/EMF culture system achieved the highest level of cellular proliferation and directed differentiation. Compared with the static culture group, the expression levels of chondrogenic factors of Sox9, Col II, and ACAN and osteogenic factors of Runx2, OCN, and Col I in RCCS/EMF culture system were 2.90±0.10, 3.53±0.05, 3.15±0.08, 7.16±0.15, 5.01±0.21 and 3.99±0.17 folds, respectively. The 'Active osteochondral' constructs (The construct is composed of chitosan/gelatin/nano-hydroxyapatite and bone-derived scaffolds) were prepared under different culture modes in vitro and implanted into the femoral condylar defect of New Zealand rabbits. After 12weeks, all culture modes could effectively promote the repair of osteochondral defects, in which the RCCS/EMF intervention had the best effect on the in vivo in-situ repair of osteochondral tissues. Furthermore, the fabricated cartilage and subchondral bone in the RCCS/EMF treatment group were most similar to the surrounding natural tissues, providing a new therapeutic idea for osteochondral tissue engineering.

Sustainable stabilization/solidification of Cu-contaminated seasonal frozen soil by epoxy resin: environmental risk assessment and engineering applicability

There are significantly toxic Cu contaminants in seasonal frozen soil areas under industrial production and mineral exploitation. However, the hydration reactions of mainstream alkaline curing agents such as cement are disturbed by the solidification and thawing of moisture, and their solidification/stabilization is ineffective to heavy metals. Therefore, there is an urgent requirement to optimize the use of current curing agents to improve the solidification/stabilization (S/S) effect of Cu contaminants in seasonal frozen soil areas. In this study, the Epoxy resin (EP) with excellent waterproofing and frost resistance was incorporated into artificially prepared Cu-contaminated soil to maintain a steady engineering application strength and inhibit the outward diffusion of toxic Cu contaminants under freeze-thaw cycles. The freeze-thaw resistance of EP-cured Cu-contaminated soil and the feasibility of EP remediation technology have been investigated, including mechanical properties, environmental effects and microstructure. The decline in mechanical strength and the increment in Cu leaching during freeze-thaw cycles are effectively suppressed by the remediation of EP. Even after 8 freeze-thaw cycles, there is merely a mechanical strength decline of 5%, solely a secondary Cu leaching of 4.74mg/L, and astonishingly a leachable index of 11.70 in the specimens with 12% EP dosage. The expansion phenomenon of pores and clay fractures under freeze-thaw cycles were gradually alleviated after incorporation of EP. The above results demonstrate the Cu-contaminated seasonal frozen soil remedied by EP are high-strength, basically non-toxic, and environmentally friendly material which are suitable for in-situ stabilization/solidification in seasonal frozen soil areas.

Overview of the III International Conference on Environmental Technologies and Engineering for Sustainable Development –ETESD-III 2024

Abstract This overview presents the key themes and outcomes of the III International Conference “ETESD - 2024,” held in Tashkent from October 17 to 19, 2024. It details the participants and proceedings, highlighting significant trends in environmental protection, biodiversity preservation, and the innovative technologies applied in agriculture. The conference addressed urgent challenges related to preventing environmental damage and discussed future prospects for advanced technologies in food production, soil protection, tillage, water conservation, and environmental research. Additionally, the event fostered dialogue on the integration of earth space systems into these critical areas, aiming to promote sustainable practices and collaborative solutions for pressing environmental issues. List of Programme Committee and Organizing Committee are available in this Pdf.

Dramatic Enhancement of Macrozoobenthic Species β-Diversity in Response to Artificial Breakwater Construction Along a Tropical Coastline

The beneficial or detrimental effects of human-built marine structures (piers, breakwaters, and seawalls) on macrozoobenthic assemblages and diversities are currently underexplored. The present study investigated the enhancement of β-diversity of oysterbed-associated species on breakwaters constructed along sandy beaches. We compared habitat complexities and species assemblages among artificial breakwater shores (ABS), a natural rocky shore (NS), and an embayment shore (ES). Oysterbed habitat complexity was found to be greatest on the ABS due to the successional colonization of the reef-forming estuarine oyster, Saccostrea echinata, followed by the colonization of boring bivalves and burrowing annelids. High-resolution taxonomic data revealed that the ABS supports the greatest species richness, including 48.1% unique species and 33.3% species shared with the embayment shore. The other shores uniquely or in combination with ABS support up to 11.1% of the total species richness associated with the oysterbeds (n = 81). Taxonomic dominance in terms of species number was Mollusca > Annelida > Arthropoda. This study reveals that ABS enhances β-diversity by ~91% (Jaccard dissimilarity index), which is driven by the sequential cascading events of (1) sheltering of shores, (2) colonization of novel habitat-forming oysters, (3) novel macrozoobenthic species recruitment from adjacent shores and sheltered embayments, including habitat-forming bivalves and annelids, and (4) the recruitment of macrozoobenthic species to boreholes. ABS habitat complexity derives from a spatially distinct, three-tiered ecological engineering system, involving (1) breakwater construction (100 m), (2) reef-forming oysters (10 m), and (3) boring bivalves and burrowing annelids (<10 cm). Irrespective of the purpose of their construction, breakwaters along extended sandy shores can potentially increase the resilience (β-diversity) and regional interconnectivity of hard surface macrozoobenthic species.

Characteristics of radon transport and optimization of ventilation parameters in large-scale underground cavern

Radon penetrates into the underground caverns through the pores/fissures of the surrounding rock, resulting in high radon concentration area and endangering the health of construction personnel. The on-site monitoring of radon concentration in the underground powerhouse of Tuoba Hydropower Station is conducted in order to study the radon concentration level. The radon transport during the construction period of underground powerhouse under forced ventilation is established by Computational Fluid Dynamics (CFD) numerical simulation method. Furthermore, the distribution characteristics and long-term evolution law of radon concentration in underground powerhouse are revealed, and reasonable ventilation optimization measures are put forward and the results show that: (1) Blasting promotes the increase of radon concentration, while forced ventilation accelerates radon transport. (2) The airflow field along the axis is divided into a vortex distribution zone, a vortex influence zone and stable regions. (3) The radon transport includes both migration and diffusion processes based on forced ventilation. (4) The radon concentration decreases with the increase of height, while exhibits low concentration in the middle and high concentration on both sides at the same height. (5) Compared with forced ventilation, the combined ventilation can improve the ventilation efficiency and shorten the radon transport time. The research results can provide a scientific basis for the safety analysis and evaluation of deep engineering environment.

Studying the intensity of the energy footprint of Chinese provinces based on the Net Primary Productivity model

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Mechanisms and rock strength measurement of two-wing polycrystalline diamond compact drill bits

Excessive or insufficient support strength causes safety hazards and economic waste in underground engineering. Addressing this requires precise sensing of variations in surrounding rock conditions. This study, based on roof anchor drilling, analyzes the full drilling process and posture, establishing a theoretical link between drilling parameters and uniaxial compressive strength. A rock property detection system was developed for specific engineering environments. Results show that in V-N mode, rock strength increases, with thrust and torque rising by 310.67% and 106.92%, respectively. In F-N mode, drilling speed decreases by 71.08%, and torque varies by 10.75%, indicating limited torque sensitivity to strength. Theoretical validation indicates that the prediction error range for rock strength under the V-N model is between 3.01% and 20.30%, with an average error rate of 10.43%. The study also examines the assumptions’ validity, F-N mode limitations, and the engineering significance of theoretical derivations, offering new insights into rock strength measurement.

Analysis of key factors for better results during continuous improvement events within engineering environment

There are few in-depth studies in the Management literature related to the development of activities implemented during the Kaizen week. This work contains a theoretical basis related to the engineering and product development environments as well as to the Kaizen tool and the Lean tool, which seek to reduce waste and implement continuous improvement. Through a case study in an aviation transportation industry, some Kaizens are analyzed in the engineering environment. With the analysis of data collected in Kaizen Weeks, a dissertative study uses three sources of data collection, between them, structured interview, and demonstrates the theory presented, proving the existence of impacting factors that influence the Kaizen week. Using percentages and multivariate analysis, it highlights the factors that have the biggest impact and the necessary attention to be given to them.

Thermal characteristics of hybrid Nanofluid (Cu-Al2O3) flow through Darcy porous medium with chemical effects via numerical successive over relaxation technique

The flow of fluids through porous media is commonly described using the Darcy model, therefore investigating hybrid nanofluids in this setting is rather new. The present work offers insightful information on how the hybrid nanofluids behave and function in porous medium. The study's conclusions may have an impact on a lot of different engineering applications like filtration systems, chemical reactors, and environmental engineering. The study concentrates on a hybrid nanofluid which consists of Cu and Al₂O₃ nanoparticles. The metallic nanoparticles such as copper have high thermal conductivity and non-metallic nanoparticles such as aluminum oxide are chemically stable and has high thermal resistance. This is the reason that the combination Cu-Al₂O₃ is believed to give better heat transfer composite than using individual nanofluids. By employing proper similarity transformation, the governing PDEs are turned into ODEs. To discretize these ODEs, the central finite difference method is used first. Then the successive over relaxation technique is utilized to numerically solve the nonlinear equations. The findings are summarized in a graphical and tabular format. The impacts of several controlling parameters such as porosity, suction, Schmidt number and volume fraction on flow pattern, thermal properties, and concentration are investigated and discussed. The streamwise and normal velocity profiles fall and those of concentration and temperature rise with increase in the values of the porosity parameter.