Recycling — Open Access Journal

The main objective of this research was to provide suitable technical, organizational, financial, legal, and social indicators for solid waste management (SWM) systems, which can be used to diagnose the current situation faced by tourist destinations (TD) in Tunisia. To this end, 33 interviews and field visits to hotels in Tunisia were carried out. Specifically, the study covers tourist municipalities, private companies, and environment and tourism authorities. A characterization analysis and a quantification of the solid waste (SW) generated by hotels were also performed. It was found that hotels generate large amounts of mixed SW, especially during the summer period. It represents, for example, 45.5% of the total SW generated per year in Hammamet, and can reach 54.2% during the summer. The interviews indicated that 83% of the hotels collect mixed waste, which is then sent to landfills. The characterization of the SW shows that hotels generate about 58% organic waste, and a minimum of 36% of recyclable waste could be valorized. From a financial point of view, the results indicated that the collected taxes from hotels do not cover the municipalities’ expenses. The findings of the research reported in this paper can be used as a decision-making support. Full article

In the city of Blantyre, much of the generated municipal waste is biowaste, typically mixed with other waste fractions and disposed at the city’s dumpsite. Energy and nutrients could be recovered; however, with many biowaste options available, choosing what technology to implement is difficult. Selecting Organic Waste Treatment Technology (SOWATT) is a tool that supports decision making for selecting a biowaste treatment option considering social, technical, and environmental aspects. SOWATT was used to evaluate options for Blantyre’s Limbe Market. Anaerobic digestion, black soldier fly processing, slow pyrolysis, in-vessel composting, windrow composting, vermicomposting, and wet-biomass-briquetting were considered as options. The performance of each alternative was assessed based on five objectives by government, NGO, and market-based stakeholders in order to determine the most acceptable option for the greatest number of people: something that is rarely done, or if it is the preferences are not rigorously quantified (e.g., stakeholder workshops) and/or weighted against specific objectives. However, given the novelty of the ranking-solicitation process, some participants struggled with the variety of options presented, and further iterations of SOWATT will address this limitation. Ultimately, vermicomposting scored highest of all alternatives and could best achieve the five objectives as prioritized by the stakeholders when implemented. Full article

A novel re-formative polymer composite manufacturing route has been developed by UK and Qatar-based Universities. This novel process recycles domestic-waste thermoplastic material, without the requirement for intensive filtering or washing operations. The produced polymer can be reinforced with recycled glass fibres, forming a structurally load-bearing composite, which may potentially be suitable for use in applications, including utility poles, railway sleepers, and fencing. Thus, infra-red (IR) analysis showed the presence of polypropylene (PP), polyethylene (PE), and polyethylene terephthalate (PET) in the commingled material. Differential scanning calorimetry (DSC) was used to determine glass transition temperatures and melting temperatures of each of the associated polymer types. Dynamic mechanical thermal analysis (DMTA) was used to determine the storage and loss modulus of the bulk commingled component. Lastly, flexural and tensile strengths of the re-formative polymer with differing proportions of glass fibre were assessed, giving a range of strengths at each glass fibre proportion for possible compositional variation in the polymer type. The recycled polymer is considered a viable structural material for replacing both wooden and concrete components, generating a polymer recycling route with concomitant environmental benefits. This plastic recycling route therefore offers a solution towards achieving climate change targets with a purposeful end-product component. Full article

The agricultural use of sewage sludge brings benefits to soil and plant crops, but due to the possible presence of contaminating substances and pathogenic organisms it is necessary to follow the criteria for safe use for health and the environment. In Brazil, the Conama 375/06 Resolution established criteria and procedures for agricultural use of sewage sludge and Paraná is one of the few states in the country to use this alternative. This case study presents the management process and the results of the agricultural destination of the sludge in Paraná State, Brazil, from 2007, year in which the resolution came into force, to 2017. The management is carried out in two spheres of action: one in the context of the sludge management units (SMU) and another in the agricultural sphere. The sludge is provided free of charge to farmers, which reduces expenses with fertilizers and soil acidity correctives, resulting in economic and social benefits to the communities where it is used. However, from the year 2011 there was a reduction in the amount destined for agricultural use. The requirements of the national regulation make the process complex, overly bureaucratic and burdensome, requiring a review of its criteria. Full article

The feasibility of using the HiPerDiF (high performance discontinuous fibre) method to manufacture highly aligned discontinuous fibres intermingled hybrid composites with flax and reclaimed carbon fibres (rCF), and the potential benefits of so doing, are investigated in this paper. It is demonstrated that, despite their hydrophilic nature, flax fibres are not affected by this water-based process. Intermingled flax/rCF hybrid composites are characterised in terms of their tensile and vibrational response. It is concluded that natural/rCF fibre hybrid composites can be a viable solution for those applications where a reduction in primary mechanical properties, e.g., stiffness and strength, is an acceptable trade-off for the enhancement of secondary properties, e.g., noise, vibration, and harshness (NVH) mitigation, and the reduction of monetary costs. Full article

There is lack of uniform nomenclature for healthcare waste (HCW) globally, which could undermine efforts to develop and implement appropriate policies relating to healthcare waste management (HCWM) in developing countries. This study sought to understand the terminologies used to describe HCW, including their definitions, categories, classification, and how they align with those that are provided by the World Health Organization (WHO)’s global manual for HCWM from healthcare facilities. The study first identified terms from the existing literature; then, it conceptually mapped the literature, and identified gaps and areas of further inquiry. Six electronic databases—EBSCOhost, Open Access, ProQuest, PubMed, Web of Science, and Google Scholar were used to search for literature. A total of 112 studies were included in the study. Despite having various nomenclature for HCW globally that align with those provided by the WHO manual, the use of varying nomenclature could create confusion among healthcare workers in the quest of managing HCW properly, especially in low and middle-income countries (LMICs). Further studies must be conducted to determine how these terminologies are interpreted and implemented in practice by healthcare workers. This will help to understand how their implementation aligns with the recommendations provided by the WHO manual. Full article

Municipal solid waste incinerator fly ash (MSWI-FA) was used synergistically with volcanic ash (VA) to synthesize Geopolymer cement. The effects of the incorporation of 0%, 30%, and 50% of VA and the alkalinity of activating solution on the structure and properties were studied by using the X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), field emission gun scanning electron microscopy (FEG-SEM), and mechanical testing. The encapsulation efficiency of the cements was carried out by using a toxicity characteristic leaching procedure (TCLP). The geopolymerization of MSWI-FA promoted the formation of new minerals such as Thernadite (Na₂SO₄), Hydrocalumite (Ca₄Al₂O₆(CO₃)_0.67(SO₃)_0.33), C-S-H, and Faujasite-Na(Na₂Ca)_0.075(Al_0.3Si_0.7)O₂(H₂O)_0.22. The Geopolymer cement synthesized with the addition of 50% of VA at 6M NaOH concentration, which exhibited the most compact microstructure. This was the highest strength with the best encapsulation ability. The microstructure analysis of the MSWI-FA-VA system revealed the coexistence of C-S-H and N-A-S-H phases as the main cementitious binders. The TCLP results of cement vis a vis raw MSWI-FA showed the leaching of metals reduced to a great extent. This was much lower than the permissible limit fixed by the United States Environmental Protection Agency (USEPA) for the toxicity characteristic. Furthermore, an attempt was made to correlate the microstructure with mechanical properties. Full article

Improper disposal of waste cooking oil into sewer systems is harmful to the environment. Through the selective collection, this highly polluting residue can be handled in a less harmful way. The present study presents an action plan for a public school in the Region of Médio Paraíba Fluminense of the state of Rio de Janeiro, Brazil to serve as a voluntary delivery point in a reverse logistics chain for waste cooking oil. A case study method with semi-structured interviews was carried out with agents who are part of the chain, including the government, commercial residue generators, collectors, the biodiesel production industry, the community, and teachers and students of the public school. Even though the reverse supply chain for waste cooking oil in the region lacks structure, this study showed that the actors were interested in correctly disposing of waste cooking oil through partnerships and agreements. In addition to the environmental benefits, environmental education actions in public schools, such as the one in this study, can help raise student awareness of issues relative to citizenship and social responsibility and promote employment and income opportunities for recyclable material collector cooperatives and industries that use waste cooking oil as raw material. Full article

The production of consumption goods made of elastomers is increasing day by day, producing large amounts of vulcanized/cured residues which constitute a serious socio-environmental problem. An option for companies that produce elastomeric residues is their incorporation in the formulations, by producing polymeric blends with ground waste elastomers. Therefore, this work aims to prepare polymeric blends composed of raw natural rubber (NR)/ground waste NR in different concentrations. The influence of vulcanization reversion as result of additional heating during compression molding on the mechanical properties of the blends was analyzed, and the relationship among vulcanization characteristics, dynamic-mechanical, morphology and mechanical properties of blends was also determined. Full article

This study investigated the use of a biomass ash produced by a fuel combination made with wood, corn stover, and corn cob as cement replacement for the production of mortar. Biomasses are now widely accepted as a substitute for conventional fuels and are becoming essential for cost-effective production of energy. This study aimed to provide an opportunity for the annual agricultural corn-crop residue, corn stover and cob, which is increasingly being used as fuel for its valuable energy content. Measurements of workability, compressive strength, and leachate properties (pH, salinity, heavy metals and calcium ion release) of mortar specimen, at different cement substitution levels and ages, were evaluated. The results obtained reveal definitive possibilities for such mixed biomass ash to be used in cement-based materials, such as mortars. Moreover, a multiple regression analysis has been reported between the mass of calcium ions leached and the mixture composition with the compressive strength. Data show that further confirmation, on a longer span of time and of other types of mechanical properties and environmental tests, would be necessary to fully implement the use of such biomass ashes in various types of cement-based construction materials, in order to divert them from landfill disposal. Full article

Mexico City introduced the new legal waste norm Norma NADF-024-AMBT-2013 in July 2017. This report compares the proposed system with three alternatives: a baseline scenario with composting of organics, a scenario which involves anaerobic digestion of organics, and a mechanical–biological treatment scenario with no source separation. The comparison was done using an Analytic Hierarchy Process. Eleven different indicators were chosen for the evaluation: general waste performance indicators (landfill disposal and recycling rates), environmental indicators (greenhouse gas emissions, acid gas emissions, Biological Oxygen Demand (BOD), and mercury content in water and soil), economic indicators (investment and operation costs) ($ per Mg municipal solid waste (MSW)), and social indicators (jobs created and social acceptance). The scenario ranking based on pairwise comparison made by 5 experts from Mexico City showed that the most sustainable scenario, environmentally, socially, and economically, is that which corresponds to Norma NADF-024-AMBT-2013 with a ranking priority of 30.78%. Full article

The practice of collecting, treating, and managing solid waste prior to disposal has become a necessity in developing and modern societies. However, over the years, most waste has become regarded as having second-rate value and could be recovered and reused for valuable goods. However, the construction costs for conventional Material Recovery Facility(s) (MRFs) have been a major barrier for its implementation, and these technologies also require considerable technical expertise, which is not often available in developing nations for the successful operation of the MRFs. Covenant University, a private mission institution undertaking a waste-to-wealth scheme, is focused on managing and processing used materials to create reusable products. Such materials included PET bottles, paper waste, food waste from cafeterias, plastic food packs, nylon, tin cans, and others. Specific areas from the university which were chosen for the survey included the residential areas for staff and students and the two cafeterias. The waste generated was characterized so as to quantify the amount of recyclable waste generated, and also to find out which was most-occurring. The survey involved the use of structured questionnaires, on-site observations, and measurements. The study revealed that the average amount of recyclable waste generated per day in the institution were 55.56% food waste, 13.46% PET bottles, 12.64% other plastic, 9.63% nylon, 4.68% tin cans, and 4.03% paper. The study establishes that adequate waste characterization is a requirement for effective integrated solid waste management, which would boost resource recovery, reuse, and recycling. Full article

This paper reports on an application of the Theory of Planned Behavior to understand the relationships between the determinants (latent variables) comprising the Theory of Planned Behavior and, based on these findings, to guide decision-making related to household recycling in South Africa. Data from a representative sample of respondents in large urban areas (n = 2004) was analyzed using Structural Equation Modeling (SEM). The results of the SEM analysis showed a good fit of the survey data to the Theory of Planned Behavior theoretical model. The Theory of Planned Behavior explains 26.4% of the variance in recycling behavior and 46.4% of the variance in intention to recycle. Only 3.3% of South Africans in large urban areas show dedicated recycling behavior, considering the recycling of five materials: paper, plastic, glass, metal, and compostable organic waste. The recycling frequency item in the recycling behavior construct is the most likely to be over-reported. South Africans lack sufficient knowledge, positive attitudes, social pressure, and perceived control that would encourage recycling behavior. Awareness drives containing moral values (injunctive norms) and information about available recycling schemes, combined with the provision of a curbside collection service for recyclables, have the greatest chance to positively influence recycling behavior amongst South Africa’s city dwellers. Full article

In this paper, a new environmentally-friendly anode for hydrogen production was developed based on 430 stainless steel with an electrodeposited cobalt layer. The novelty of this work is the cobalt source once the electrodeposition bath was obtained from acid dissolution of a spent Li-ion battery cathode. The oxygen evolution reaction on electrodeposited cobalt in 1 M KOH is compatible with the E. Kobussen mechanism. The water discharge is related with reaction determinant step in low overpotential. The cobalt electrodeposition (3 Ccm⁻²) promotes a significant improvement of 430 stainless steel anodic properties for oxygen evolution reaction. When the overpotential reaches 370 mV, the density current for 430 stainless steel with electrodeposit cobalt is 19 mA·cm⁻² against 0.80 mA·cm⁻² for 430 stainless steel without cobalt. Thus, the anode construction described in this paper is an excellent option for Li-ion battery recycling. Full article

A small percentage of South Africans regularly recycle most of their recyclables, which was only 4% and 7.2% in 2010 and 2015, respectively. This empirical quantitative study, the first study on this scale in South Africa, aimed to ascertain the reasons why people do not recycle. This paper reports the results from a survey conducted among a representative sample of 2004 respondents in eleven of South Africa’s large urban areas. Each respondent selected three main reasons why people do not recycle from ten possible options as well as the one main reason. The results show that (i) insufficient space, (ii) no time, (iii) dirty and untidiness associated with recycling, (iv) lack of recycling knowledge, and (v) inconvenient recycling facilities are perceived as the main reasons why people do not recycle. Non-recycling households (74% of the respondents) give high priority to time and knowledge. Low recyclers—those that sporadically recycle few items—and young South Africans give high priority to services (inconvenient facilities and no curbside collection). Lack of knowledge is an important factor for people from dense settlements as well as the unemployed looking for work. Improved recycling services such as regular curbside collections have the potential to overcome time and space barriers. Recycling services as well as recycling knowledge will have to improve to encourage the youth, the unemployed, and those living in informal areas to recycle and realize the opportunities locked in the waste sector. The perceptions of respondents from non-recycling households differ from those from recycling households. The larger representation of non-recyclers in developing countries emphasize the importance of understanding local evidence when comparing and implementing results from developed countries. The learning from this study could also assist other developing countries to encourage household participation in recycling initiatives. Full article

The management model for the National Solid Waste Policy to develop sustainable actions, proposes the social inclusion of recyclable waste pickers in the waste management system. Compliance with the law, the form of participation of the waste pickers, and incentive mechanisms are configured as a relationship open to analysis. Therefore, the aim of this work was to investigate the potentials and limitations of a recycling cooperative, in terms of social technologies and inclusion, to encourage local development. The qualitative approach was aided by structured questionnaires, semi-structured interviews, and participant observation. The resulting evidence suggests that the organization of a cooperative, enabled access to information on the legislation of the National Solid Waste Policy. It showed the need to strengthen relationships with education institutions and public authorities. Despite the low levels of education of the members of the cooperative, projects and knowledge could be developed to aid social technologies. No technological innovations were observed, nor the production of alternative artifacts for recyclable materials. This weakens the cooperative in terms of articulation among peers, most notably the integration of the Catamare cooperative in the network of Cataparaná, to support the sale of material produced for industry. It may be concluded that joining the cooperative improved the social, economic, and political conditions of the members, but there were also structural limits to the recycling production chain that were not considered in the National Solid Waste Policy; and to a certain extent this weakens the development of sustainable actions. Furthermore, the organization of the cooperative hindered the development of social technologies and the social inclusion of the waste pickers. Full article

This study evaluates the feasibility of stabilizing clay bricks with marble cutting waste (MCW). This waste is currently discarded in huge quantities as sludge resulting from the sawing of marble blocks to slabs and the processes of disposing of grinding and polishing marble in landfills located around the marble processing factories in the Shaq El-Thoban industrial zone, Cairo governorate, Egypt, which causes negative impacts on the environment, health, and sustainable development. Experimental investigations were carried out to explore the effect of the addition of MCW in different clay–base mixes using varying percentages of up to 20% at the expense of the hydrated lime. Cement, hydrated lime, and MCW are the three types of solidification agents used, and clay and sand were also added in the formulations of the unfired clay brick specimens. Laboratory cylindrical stabilized and compressed specimens were made; then, they were cured in a humidity chamber for two weeks and four weeks. Afterwards, they were air dried, tested, and evaluated according to the Egyptian code for the building by the stabilized and compressed earth soil (ECBS, 2016). To enhance the durability of the cured specimens, transparent silicon-based paint was used. The results demonstrated that the optimum content of marble sludge waste (MCW) was 15% when used as replacement for hydrated lime in the production of stabilized clay brick. For all of the samples, the use of silicon-based paint was found to improve the strength and water resistance of the stabilized clay bricks. The use of local waste materials as a substitute for a hydrated lime binder reduces both the cost and environmental impact associated with block production. Full article

India is currently facing a mounting challenge related to municipal waste management, due to an increasing urban population, and their high consumption lifestyles. India also has the world’s highest number of young people in the 10–24 years age group. The study applied the theory of planned behaviour (TPB) model to predict school students’ recycling intentions in Delhi, the capital of India and one of the highest producers of municipal solid wastes in the country. Data were collected from a school in New Delhi and the sample size consisted of 272 students from 9th and 10th grades. The TPB model explained 56% of the variance in the students’ intentions to recycling. The predictor ‘subjective norm’ appeared to have the strongest impact on the students’ recycling intentions, followed by ‘attitude’ and ‘perceived behavioural control’. It indicated that social factors are driving the Indian youth’s recycling intentions. It is important that the policymakers promote recycling as a social trend in India and provide adequate facilities to the public so that they can participate in recycling activities without facing difficulties. Schools also have a role in increasing students’ awareness of recycling and motivating them to participate in household waste management practices. Full article