Amount Of Solid Waste Research Articles

Feasibility of Using Recycled Materials in Construction Materials

The increasing amount of solid waste has become a significant environmental issue that has garnered significant attention and concern. In an effort to mitigate the adverse effects commonly associated with prominent sectors and simultaneously promote credibility in the energy- and resource-intensive realms of development and construction, significant endeavors have been directed towards competitive areas of strength for the purpose of recycling, with the ultimate goal of utilizing such materials in sustainable development products. The present study provides an overview of the ongoing evaluations pertaining to the utilization of conventional and enhanced solid waste for the production of geo-polymer composites. Great attention is devoted to the implementation of these geo-polymer composites. The primary findings of this study revealed that both ordinary and sophisticated solid waste have the potential to be integrated into geo-polymer composites in various forms, such as precursor, complete, additive, reinforcement fiber, or filler material. The findings indicate that the utilization of such waste may have a negative impact on certain properties of geo-polymer composites. However, this issue can be mitigated through the implementation of an open degree plan and appropriate treatment techniques, which can facilitate the recycling process. In conclusion, a concise discourse is presented to acknowledge the significant need for future research and enhancement in advancing the utilization of solid waste materials in the emerging sustainable geo-polymer industry. This study proposes an improved ecological solution for managing municipal and industrial solid waste by transforming waste materials into environmentally friendly construction materials with consistent properties. Special attention is given to the overall performance of geo-polymer composite products. The primary findings of this study reveal that urban and industrial solid waste can be efficiently incorporated into geo-polymer composites through the use of precursors, aggregates, additives, reinforcing fibers, or filler materials. The results indicate that while the inclusion of waste materials may negatively impact certain properties of geo-polymer composites, a well-designed protocol and effective treatment approach can mitigate these adverse effects and facilitate the recycling process. Finally, a brief dialogue is presented to differentiate the key needs in forthcoming research and development aimed at enhancing the utilization of solid waste materials in the upcoming sustainable geopolymer sector. This study provides guidance for the sustainable management of urban waste by transforming waste materials into environmentally friendly construction materials.

Eficiencia en la gestión de residuos sólidos urbanos en los municipios distritales de la macrorregión sur del Perú

The central objective of this study is to analyze the level of efficiency in the management of urban solid waste in the district municipalities of the southern macroregion of Peru in the year 2022 and how it is affected by different variables and management strategies. For this, information from the National Registry of Municipalities (RENAMU) for the year 2022 prepared by the INEI was used. The hypothetical-deductive method was used with a quantitative approach through an envelopment analysis model that allowed estimating the level of efficiency of the 174 urban district municipalities. Subsequently, a Tobit model was estimated to find how the management instruments affect the level of efficiency of the municipalities. It is concluded that some districts operate with high efficiency in solid waste management, such as Machupicchu, Pichari, Juli, while others have room to use their resources efficiently, such as Potoni, Cabanillas and Quilcapuncu. Furthermore, it was found that municipalities with greater efficiency manage to collect a greater amount of solid waste per capita and a higher level of waste collection coverage with similar resources to those inefficient municipalities. On the other hand, the implementation of waste management plans, urban development plans and institutional strategies are positively and significantly related to the level of efficiency.

Mechanical and acoustic performance of mortar with partial replacement by biochar from civil construction wood waste at advanced ages

Civil construction generates large amounts of solid waste, most of which are non-toxic, but extremely voluminous, resulting in a contemporary sanitary health problem. Furthermore, cement fabrication, a widely used binding material, is responsible for the emission of 8% of the world’s CO2 into the atmosphere, making it an industry with a great environmental impact. The consumption figures of cement show an significant increasing over the years. Therefore, much research has focused on the search for energy efficiency in the production processes of cement and materials with potential use as additions, allowing the reduction of clinker consumption, the main component of the cement. In this sense, this research made use of wood waste from civil construction, and through the pyrolysis process, partially replaced cement with biochar at high levels compared to existing research, seeking to find an efficient replacement limit and analyzing its sound absorption and mechanical properties at advanced ages. Mortars were produced with levels of 5%, 10%, and 15% (m/m), replacing cement with biochar. The results demonstrated better mechanical performance at advanced ages, up to 30% for compression and 15% for tensile strength with 10% biochar, and lower water absorption by capillarity. Its acoustic performance showed that the samples with biochar did not exhibit properties of a sound-absorbing material.

Assessing the circularity status of waste management among manufacturing, waste management, and recycling companies in Kigali, Rwanda

A high quantity of waste is generated from industrial activities by manufacturers across metropolitan cities compared to smaller cities with fewer industrial activities. Adopting Circular Economy principles in waste management has the potential for sustainable waste management to reduce the quantity of waste at dumpsites and harmful emissions from wastes. The study was conducted to assess circularity status and challenges for attaining higher circularity by Kigali’s manufacturing, waste collection, and waste recycling companies using the 10-R framework. The study also sought to build estimates for industrial solid waste quantity and methane emissions for the next 10 years (2020–2030) in Rwanda. A mixed method approach was utilized where primary data was collected from manufacturing, waste collection, and waste recycling companies using a validated questionnaire and an in-depth interview guide. Thematic, descriptive analysis and First Order Decay methods were used to analyze the qualitative, quantitative, and secondary data. Results show that adopting the 10-R principles of circular economy was low and varies across manufacturing, waste collection and recycling companies. There were instances of high adoption of R3-Reuse and R8-Recycle with a mean score of 7.17 and 7.21 among manufacturing companies. R7-Repurpose (8.80) recorded a high adoption rate among waste collection companies and a medium level of adoption for R7-Repurpose (3.50) and R9-Recover (3.00) among recycling companies. The overall low adoption toward attaining circularity was attributed to various economic, institutional, infrastructural, operational, attitudinal, and technological challenges. In 2030, it is projected that 922 Gg of industrial waste will be deposited in solid waste disposal sites in Rwanda; with an estimated methane emission of 157 Gg Carbon dioxide equivalence. It was recommended among others, that human resource capacity development should be prioritized to drive the adoption of the 10-R principles across manufacturing, waste collection, and waste recycling companies in Kigali, which can reduce the quantity of wastes that ends at dumpsites and methane emissions that contribute significantly to global warming.

Correlation between waste generation, population and GDP of cities in Sergipe, Brazil

The problem of solid waste (garbage or rubble) is a global problem that affects the environment, public health, and the quality of life of people all over the world. In this work, a literature review and quantitative research were carried out on the websites of the Institute of Water and Sanitation and Dataviva of the Federal University of Minas Gerais, to collect the data needed to verify whether or not there is a correlation between population size, waste generation and gross domestic product (GDP) per capita. This work used the correlation coefficient, which is widely used to measure the relationships between variables and what they represent, and is important for drawing up overviews in studies with many related variables so that it is possible to understand how the variability of one affects the other. The results show that population size and per capita waste generation showed a weak positive correlation and GDP per capita and per capita waste generation showed a very weak negative correlation. It can be concluded that economic and population aspects can influence the total volume of waste generated, but that they did not emerge as determining factors in isolation, showing that different populations (in terms of age structure, household arrangement structure, and cultural habits, among others) practice different consumption patterns, generating different amounts of solid waste.

Alternative materials in civil construction: a comparison between the use of conventional and recyclable materials, bricks and concrete for sustainable constructions

Civil construction causes environmental impact, as it consumes natural resources and generates a large amount of solid waste, raising concerns about the survival of future populations. Therefore, there has been a search for sustainable materials, to add non-conventional materials to the mass that forms bricks, blocks, pavements or make up walls in mud constructions, saving cement, sand, lime and stone. This work aims to present the aggregates that have already been experimented, tested, and that can compose the raw material with less disastrous results to the environment. A review was made in the literature, where articles, monographs, dissertations that address the subject were found. From them, a collection of the viability, opportunity and positivity of the use of aggregates was made, bringing a comparative result. The research can be useful as a basic element to guide those who intend to apply such materials, as well as to trigger and subsidize new studies, with new tests and experiments, both of these materials presented, and others that may still arise.

Evaluation of the Bioenergy Potential of Blends (Green Coconut Shells and Fish Scales) as a Feedstock in Thermochemical Processes for Clean Energy Production

Brazil is among the world’s largest producers of green coconut, which contributes to inappropriate disposal and socioenvironmental impacts. Concomitantly, some of its coastal cities produce a great diversity of fish and large amounts of solid waste. This paper reports on the use of samples of fish scales (100FS) and green coconut shells (100GCS) and their mixtures in 75%FS:25%GCS (B25), 50%FS:50%GCS (B50), and 25%FS:75%GCS (B75) proportions and quantification of their Higher Heating Values (HHV) and Lower Heating Values (LHV), and Ultimate (UA) and Proximate Analyses (PA). Their thermal behavior was investigated by thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC), whereas scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transformed infrared (FTIR) were employed for analyses of their physicochemical and morphostructural properties. When compared to in natura samples, SEM images of the blends detected a structural disorder and a highly fibrous structure with an elongated chain and surface roughness. HHV were superior in samples with 100GCS (16.64 MJ kg−1), B75 (15.80 MJ kg−1), and B50 (14.98 MJ kg−1), and lower in B25 (14.16 MJ kg−1) and 100FS (13.03 MJ kg−1), with acceptable values for different biomasses. TG/DTG and DSC curves showed similarities among the samples, with the detection of their main thermoconversion stages. According to the data, the samples can be applied as renewable energy sources to mitigate socioecological illnesses and social vulnerabilities resulting from the archaic and inadequate management of solid waste.

Концепция использования искусственного интеллекта в автоматизированных системах управления твердыми бытовыми отходами

In the Republic of Kazakhstan, there is currently no proper control and accounting of solid waste by the state and culture, a high standard of living for the majority of the population. To solve the problem of automated MSW management using AI, it is proposed to develop a knowledge base, the level of education, distribution by collection zones in the city, socio-economic stratification, population and the amount of solid waste generated over a certain period of time is taken as a set of input data. The initial filling of the knowledge base is provided according to the latest population census of the Republic of Kazakhstan https://stat. gov.kz/ru/national/2021/. For predictive estimates of the volume of solid waste, the method of the forest conveyor with Bayesian optimization (RFBO) was used, the algorithm and architecture of the software solution are quite informative. The reliability of predictive decisions on the volume of solid waste presented by the program is at least 90%, taking into account the correctness of the input data set, the program code is written in Python. The solution proposed in the article to the problem related to the automation of solid waste management is based on international experience, taking into account the identified shortcomings, as well as the prospects and trends of understanding by residents of the country and public utilities of the country, a possible garbage collapse. The possible disadvantages of the program are the availability of constant access to the Internet, the need for a large amount of RAM, and computer performance. The program can be used as a ready-made solution for predictive estimates of solid waste for various regions

Stabilization of heavy metals in solid waste and sludge pyrolysis by intercalation-exfoliation modified vermiculite

Increasing amounts of solid waste and sludge have created many environmental management problems. Pyrolysis can effectively reduce the volume of solid waste and sludge, but there is still the problem of heavy metal contamination, which limits the application of pyrolysis in environmental management. The intercalated-exfoliated modified vermiculite (IEMV) by intercalators of sodium dodecylbenzene sulfonate, hexadecyltrimethylammonium bromide and octadecyltrimethylammonium bromide were used to control the release of Cd, Cr, Cu, Zn and Pb during pyrolysis process of sludge or solid waste. The retention of heavy metals in sludge was generally better than that in solid waste. The IEMV by octadecyltrimethylammonium bromide as the intercalator calcined 800 °C (STAB-800) was the best additive for heavy metal retention, and the retention of Cr, Cu and Zn was significantly better than that of Pb and Cd. Cr, Cu, Zn and Pb were at low risk, while Cd had considerable risk under certain circumstances. New models were proposed to comprehensively evaluate the results of the risk and forms of heavy metals, and the increasing temperature was beneficial in reducing the hazards of heavy metals by the addition of STAB-800. The reaction mechanism of heavy metals with vermiculite was revealed by simulation of reaction sites, Fukui Function and Frontier Molecular Orbital. Thermal activation-intercalated-exfoliated modified vermiculite (T-IEMV) is more reactive and had more active sites for heavy metals. Mg atoms and outermost O atoms are the main atoms for T-IEMV to react with heavy metals. The Cr, Cu and Zn have better adsorption capacity by T-IEMV than Pb and Cd. This study provides a new insight into managing solid waste and sludge and controlling heavy metal environmental pollution.

Development of municipal solid waste management guidelines in biological crisis based on international experiences and considering local techno-economic characteristics

In addition to health consequences, the Covid-19 pandemic has had important effects on the environment and lifestyle. Municipal solid waste management faced serious challenges due to consequence of the Covid-19 pandemic. In this study, the effects of the Covid-19 pandemic on the quantity and composition of municipal solid waste in Tehran were investigated. The international experiences of municipal waste management in the Covid-19 pandemic were reviewed and the results were used to develop a guideline for waste management in epidemic conditions adapted to local characteristics. The results showed that changes in the quantity of municipal solid waste affected by the Covid-19 pandemic had temporal and spatial variation. The most change in quantity by 15.81% was seen at the beginning of the pandemic, and non-recyclable waste had the most ratio change among the components of municipal solid waste (144%). The emergence of scattered point sources of infectious waste generation was the most important consequence of the epidemic in municipal solid waste management. These experiences were the basis for defining a guideline for the management of municipal solid waste in biological crises. A guideline in six activities and more than 90 items based on the local characteristics such as available equipment, general culture, local economy, and quantitative changes was defined.

Solid waste characteristics and management strategies at ST Theresa (STT) and Holy Cross (HC) hospitals in Chirumanzu rural District, Zimbabwe

AbstractManagement of solid waste from rural hospitals is among major problems affecting developing countries. This is mostly attributed to inadequate data related to quantity and quality of hospital solid waste. Similarly, information related to rural hospital solid waste characteristics and management is limited in Zimbabwe. However, SDGs complemented by Zimbabwe Vision 2030, NDS 1 advocates for sustainable solid waste management. Hence, enough data related to characteristics of solid waste from rural hospitals are required to attain sustainability. This research focuses on hospital solid waste characteristics and management strategies at STT and HC rural hospitals. Descriptive cross sectional research design which triangulates qualitative and quantitative paradigms was utilized. Interviews, observations, questionnaires were used to collect data. Quantitative data were analyzed using Statistical Package for Social Sciences whereas qualitative data were subjected to content analysis. Solid waste generated at STT encompasses non-hazardous (77.35%), hazardous waste (22.65%). At HC solid waste consists of non-hazardous (79%) and hazardous waste (21%). Respondents at STT (70.4%) and HC (72.7%) noted that solid waste was increasing. Solid waste was increasing due to various factors namely high use of disposable materials at HC (35.1%), STT (42.5%) and increase of patients at HC (30%) and STT (29.7%). Solid waste was indiscriminately stored in various types of containers although pedal operated bins and sharp containers were highly used at STT (72.4%) and HC (69.1%). Waste receptacles were transported to disposal sites using wheelbarrows and manual handling. Open pits and burning were among disposal strategies but incineration was regarded as the golden approach at STT (44.8%) and HC (41.8%). Inappropriate hospital solid waste management was due to shortage of finance at STT (38.1%) and HC (30.9%) and unawareness among health workers. Although it was worsened by lack of all stakeholder participation at STT (79.0%) and HC (76.4%). Consequently, the study recommended application of strategies which support circular economy, integrated approach, raising awareness of health workers and provision of enough resources to rural hospitals.

Transitioning towards circular economy through municipal solid waste analysis and characterisation using SowaCLINK software

Municipal solid waste constitutes environmental challenges globally, especially in developing countries, due to increasing waste generation, population growth, inadequate infrastructure, lack of data and poor planning. This study aims to conduct a comprehensive waste audit on the municipal solid waste generated in Aba, a metropolis in southeastern Nigeria. Aba is a commercial city considered the messiest because of the massive municipal solid waste generation and poor management. The study investigated the energy potential and waste regeneration. Municipal solid waste data was sought to provide insight into the quantity and composition of municipal solid waste. The methodology was site-based, in line with the standard test method for determining unprocessed municipal solid waste (ASTM-D5231-92) and SowaCLINK software, a computer-based environmental application, was used for characterization. Linear extrapolation was adopted to quantify the rate of municipal solid waste generated. The geometric mean was applied to forecast the area’s population for a 10-year design period. The chemical elements of the characterized municipal solid waste were utilized based on the ASTM-D5291 standard for municipal solid waste thermochemical conversion, and the high and low heating values were analyzed. The outcomes provided energy recovery potential, the electrical power potential, and the power to the grid of electrical power of the municipal solid waste. The results obtained were 0.7813 kg/p/d and 490,268 t/y for a population of 1,719,185 persons. The percentage of the municipal solid waste components with energy potential was 71%, comprising 48% combustible and 23% organic components on average. The high heating value computed was 176.5 MJ/kg, and the low heating value was 14 MJ/kg. The energy recovery potential was 3,709,463 MWh, the electrical power potential was 38,680 MW, and the power to the grid was 26.1 MW daily. The research reveals a promising direction in transitioning from the linear economy of municipal solid waste management toward implementing an integrated sustainable municipal solid waste management based on the circular economy model. The study recommends adopting detailed steps to proffer solutions to the environmental challenges associated with municipal solid waste in most low-middle-income countries to achieve sustainable municipal solid waste management while generating electricity and bio-fertilizers through incineration and anaerobic digestion.

A Practical Deep Learning Architecture for Large-Area Solid Wastes Monitoring Based on UAV Imagery

The development of global urbanization has brought about a significant amount of solid waste. These untreated wastes may be dumped in any corner, causing serious pollution to the environment. Thus, it is necessary to accurately obtain their distribution locations and detailed edge information. In this study, a practical deep learning network for recognizing solid waste piles over extensive areas using unmanned aerial vehicle (UAV) imagery has been proposed and verified. Firstly, a high-resolution dataset serving to solid waste detection was created based on UAV aerial data. Then, a dual-branch solid waste semantic segmentation model was constructed to address the characteristics of the integration of solid waste distribution with the environment and the irregular edge morphology. The Context feature branch is responsible for extracting high-level semantic features, while the Spatial feature branch is designed to capture fine-grained spatial details. After information fusion, the model obtained more comprehensive feature representation and segmentation ability. The effectiveness of the improvement was verified through ablation experiments and compared with 13 commonly used semantic segmentation models, demonstrating the advantages of the method in solid waste segmentation tasks, with an overall accuracy of over 94%, and a recall rate of 88.6%—much better than the best performing baselines. Finally, a spatial distribution map of solid waste over Jiaxing district, China was generated by the model inference, which assisted the environmental protection department in completing environmental management. The proposed method provides a feasible approach for the accurately monitoring of solid waste, so as to provide policy support for environmental protection.

Optimized Solid–Liquid Separation of Phenolics from Lavender Waste and Properties of the Dried Extracts

Lavender distillation produces huge quantities of solid waste yearly. This waste is usually discarded, resulting in serious environmental issues. However, it still contains residual essential oil and other bioactive compounds. This research reports on the development and comparison of optimized solid–liquid separation methods, i.e., microwave- (MAE) and ultrasound-assisted extraction (UAE) of phenolic compounds from lavender distillation waste. The optimal pretreatment conditions, such as waste moisture content and particle size, were also determined. The extracts were spray- or freeze-dried and the resulting powders were characterized for their physicochemical properties. The majority of the original phenolic compounds in lavender were found in the leachate fraction after distillation (61%), whereas 43% was found in the solid waste. Drying of the solid waste before extraction affected the process efficiency. UAE led to a higher phenolic content and greater antioxidant properties compared to MAE. Drying (spray or freeze) the extracts did not significantly affect their phenolic content, whereas the use of maltodextrin as a drying agent improved the drying process yield, especially when using the freeze-drying method. It is concluded that valorization of lavender distillation wastes can be achieved via an integrated process consisting of a green extraction method and a consequent drying process that results in a stable bioactive powder.

Biogas Production from Kitchen Waste Produced in College Canteens

This research paper delves into the possibilities of engendering biogas from the kitchenette waste produced in college canteens. The goal is to evaluate whether it is feasible and effective to use kitchen waste from college canteens as a cause for producing biogas, which can be exploited as an energy store. Moreover, trials will be led to recognize the conditions for producing biogas. The management of solid waste has grown significantly in importance as urbanization increases. The amount of solid waste produced has increased dramatically as a result of India's economy growing quickly. India's 429 million urban residents produce 62 million tonnes of waste annually. The monetary viability and environmental recompenses of employing biogas systems in college canteens will also be inspected. The research methodology encompasses assemblage data from college canteens scrutinizing the composition of the waste decisive how much waste is engendered and assessing the potential for biogas production. The discoveries will offer perceptions, into the viability of generating biogas from kitchen waste while endorsing waste management practices and renewable energy generation.

Influence of Industrial Symbiosis on Solid Waste Reuse in Manufacturing Industries in Kisumu County, Kenya

Industrial symbiosis (IS) is a practical approach to sustainable economic and environmental management involving exchanging materials, energy, water, and by-products among industries. While IS has been extensively studied in developed countries, its implementation in developing countries still needs to be improved. The purpose of the research was to assess the influence of geographical proximity and symbiotic intensity on the exchange of solid waste materials. This study employed a descriptive, cross-sectional research design and examined 41 manufacturing industries in Kisumu County, Kenya. A combination of quantitative and qualitative data was collected through questionnaires administered to technical officers in the industry. Besides, in-depth interviews with industry experts, county administrators, and industry association representatives were conducted, providing valuable insights and perspectives on the subject matter. The findings established that geographical proximity did not significantly influence types of waste exchanged (p = 0.298, p = 0.327, and p = 0.535) using nutrient-value waste as the reference category. This finding was likely due to high variability in distance between industries in the symbiotic exchanges. In contrast, the symbiotic intensity statistically significantly influenced the amount of solid waste reused in the network (Adjusted R2 = 0.113, p = 0.039). Furthermore, it was established that increasing the number of actors in the network (β = 0.324) can significantly impact solid waste reuse more than increasing the number of types of waste being exchanged (β = 0.243). This study underscores IS as a sustainable alternative to conventional manufacturing, especially in developing countries, while indicating that factors other than geographical proximity shape symbiosis.

Isolation and Potential Testing of Cellulolytic Fungi from Tea Processing Waste

Tea as one of the long-established agricultural commodities in Indonesia, generates significant amounts of solid waste throughout the year. Tea waste, which has a low C/N ratio, can be used as compost to replace inorganic fertilizers, because it contains high nitrogen. The high carbon content can also be utilized as a soil ameliorant that acts as a soil buffer, because it has a high water absorption capacity. This research was conducted at the Soil Biology Laboratory, Faculty of Agriculture, Universitas Sumatra Utara. Cellulolytic microorganisms from tea factory waste were isolated using Carboxyl Methyl Cellulase (CMC) media, and superior fungal isolates were tested for their potential to degrade organic materials in raw tea factory waste. The results of the study revealed the presence of 5 fungal isolates, with isolate J3 showing potential in decomposing organic materials, resulting in a C/N ratio of 12.62, followed by a pH of 6.96. Fungal with the best potential test results can be used as decomposers in organic matter that is high in cellulose content which is difficult to decompose.

A Study on Physical Characterization of Municipal Solid Waste of Jammu City on the basis of Socioeconomic Status of the Population

Generation of waste has been associated with humans since dawn of civilization. But in recent decades due to factors like ever increasing population, urbanization and industrialization, the amount of waste generated has spiked to enormous proportions. The composition of waste has significantly changed since plastic was first used in the middle of the 19th century. MSW management is a significant environmental concern in India. Jammu City generates an immense amount of solid waste, approximately 350–400 metric tons (MT) daily, with an individual generation rate of around 0.55 kg per day. MSW management in Jammu City is handled by the Jammu Municipal Corporation (JMC). In the city, MSW collection, transportation, and disposal are all handled by JMC. MSW of Jammu city is disposed at Kot Bhalwal which is an open landfill site. As of now no prior treatment of MSW is being done. Present study attempts to assess the current state of MSW management in Jammu city. Sampling was done in the month of July, 2022 from 15 different wards classified in the basis of socioeconomic status and physical characterization of MSW was conducted. This paper analyzes the results obtained from physical characteristics of MSW from three diverse socioeconomic groups HIG, MIG and LIG. This would help in understanding the waste generation pattern of different socioeconomic groups. MSW from MIG contains large proportion of organic matter (55%) and is thus suitable for composting and bio-methanation, however MSW collected from HIG locality contain high proportion of inorganic materials like paper/cardboard, plastic, polythene and textile waste and therefore it is suitable for Refuse Derived Fuel (RDF) facility. MSW from Jammu city also contain high fraction of inert waste (20% to 45%). Inert waste can be easily disposed but when it is mixed with MSW it increases the volume and weight of total MSW and therefore increase the difficulty if MSW management. This study also explores the alternative approaches to MSWM in Jammu city. Data generated by present study will be beneficial to JMC for designing future course of action for management of MSW of Jammu City.

Household Solid Wastes: Collection and Disposal Methods in Abuja Municipal Area Council (AMAC), Federal Capital Territory, Nigeria

Objectives: This study was to assess the composition and quantity of solid wastes and their collection and disposal methods in Abuja Municipal Area Council, Federal Capital Territory of Nigeria. Method: A total of 420 well-structured questionnaires (in English language) were administered to consenting participants to obtain information on methods of waste collection and disposal. Secondary data such as waste characteristics and types generated were collected from the Abuja Environmental Protection Board (AEPB) records from January to December 2020. Results: Proportion of solid wastes generated in AMAC were in the order Food and other organic wastes, Papers, water sachets, plastics, metals, glass and textiles, 46.23%, 20.27%, 13.23%, 8.53%, 4.88%, 4.37% and 2.45% respectively. On waste collection, significant 55.71% proportion of the respondents choose government-approved bins, 25.23% use household items while 19.04% employed commercial waste collectors (X2 = 32.5454, df= 12, P= 0.00113). An insignificant 47.4% of the respondents in the study claimed to patronize only government approved dumpsites in disposing off their household wastes, 24.5% at any available open spaces while 24.3% dumped their wastes in their private backyards, 3.80% disposed the wastes in drainages (X2 = 18.8314, df= 18, P= 0.4022). Conclusion: This study successfully achieved the objective for which it was set. This study successfully assessed the composition and quantity, collection and disposal methods of waste generated in AMAC, FCT, Nigeria.

Atomic-scale Ru anchored on chromium-shavings as a precursor for a pH-universal hydrogen evolution reaction electrocatalyst.

In the leather manufacturing industry, the management of substantial quantities of solid waste containing chrome shavings remains a formidable challenge. Concurrently, there is a pressing need for the development of pH-universal and economically viable electrocatalysts for the hydrogen evolution reaction (HER). In response to these intertwined challenges, this study proposes an innovative approach wherein the amino groups present on the surface of chrome shavings are utilized to immobilize single ruthenium atoms during pyrolysis, thereby facilitating the synthesis of hydrogen evolution electrocatalysts. The optimized sample, denoted as CN/Cr2O3/Ru-1, demonstrates exceptional electrocatalytic performance, exhibiting an ultra-low overpotential of -28 mV in 1.0 M KOH at a current density of 10 mA cm-2, and it also exhibits good performance in acidic and neutral electrolytes. Importantly, these overpotentials surpass those reported for many previous ruthenium-based catalysts. Density functional theory (DFT) calculations elucidate that both oxygen (O) and chromium (Cr) moieties within Cr2O3 can engage in favorable interactions with the coordination patterns of the ruthenium (Ru) atoms, thereby elucidating the synergistic enhancement conferred by the chromium element in CN/Cr2O3/Ru, which ultimately facilitates and promotes the catalytic activity of the ruthenium atoms serving as the catalytic center. This facile synthesis route not only presents a green solution for addressing waste chromium pollutants but also offers a promising avenue for the development of high-performance, cost-efficient electrocatalysts.