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This paper aims to explore the intellectual structure shaping the circular economy (CE) discourse within the built environment in Africa.

The study adopted a bibliometric analysis approach to explore the intellectual structure of CE in the built environment in Africa. The authors collected 31 papers published between 2005 and 2021 from the Scopus database and used VOSviewer for data analysis.

The findings show that there are six clusters shaping the intellectual structure: demolition, material recovery and reuse; waste as a resource; cellulose and agro-based materials; resilience and low-carbon footprint; recycling materials; and the fourth industrial revolution. The two most cited scholars had three publications each, while the top journal was Resources, Conservation and Recycling. The dominant concepts included CE, sustainability, alternative materials, waste management, lifecycle, demolition and climate change. The study concludes that there is low CE research output in Africa, which implies that the concept is either novel or facing resistance.

The data were drawn from one database, Scopus; hence, adoption of alternative databases such as Web of Science, Google Scholar and Dimensions could potentially have yielded a higher number of articles for analysis which potentially would result in different conclusions on the subject understudy.

This study made a significant contribution by articulating the CE intellectual structure in the built environment, identified prominent scholars and academic platforms responsible for promoting circularity in Africa.

Sustainability issues on economic, environmental and social perspectives have drawn attention of environmentalists, ecologists and governments. In this context, circular economy provides an opportunity to transform waste into resources, reduction of production and consumption activities; and reduction of carbon footprints, all at the same time. The purpose of this paper is to develop a strategic framework for measuring circular supply chain management.

A grounded theory approach has been used to develop the strategic framework for circular supply chain management.

This study provides an integrative framework for studying, designing and evaluating circular supply chain management performance matrix.

A conceptual strategic framework has been proposed to measure the performance of circular supply chain management. Further empirical studies may be carried out to validate the framework.

The conceptual strategic framework provides key indicators for reducing material consumption, reducing waste, reducing carbon footprint and recycling opportunities throughout the supply chain. These may be utilized by practitioners for gaining competitive advantage.

This paper provides insights into development of circular supply chains that provides opportunities for cost reduction and securing competitive advantage for a business in the long run.

This study aimed to investigate the suitability and cost-benefit of using copper tailings as partial replacement of sand in concrete production. The study was motivated by the accumulation and non-use of copper tailings in dams among them tailing dam 25 also known as TD 25 in Kitwe city of the Copperbelt province in Zambia that take up approximately 111 hectares of unused land.

Laboratory experimental approach of concrete production based on water/cement ratios of 0.3 and 0.5 was used because this was an exploratory study designed to establish the primary performance of concrete. In total, 30 concrete cubes were cast based on the two water-cement ratios. In total, 0% to 30% partial sand replacement with copper tailings was used in both mixes with the 0% copper tailings replacement being the control mix and reference point. Other concrete tests included workability, density, compressive strength and element composition analysis.

Results revealed that copper tailings from TD 25 were suitable for partial replacement of sand in concrete. Thirty per cent of sand replacement with copper tailings was established as the maximum replacement amount to produce optimum compressive strength values from both mixes. The drier mix of 0.3 water-cement ratios produced higher compressive strength results of 23 MPa at 28 days of concrete curing with 2.34% as optimum concrete cost reduction.

The research results provide the cost-benefit analysis and savings that can be attained from using cheaper copper tailings based concrete. The study further provided the quantity of land available for development arising from absorption of copper tailings as a sustainable construction material. The local authority now has statistics and numerical values that it can use to absorb copper tailings as a concrete raw material.

The study provides guidance on optimum concrete grade produced and cost reduction details of copper tailing-based concrete to support for local authorities in suitable land wand waste management using real data.

The second part of this article identifies the technological developments which will influence future organisational structure and design.

Currently, China is the largest coal producer and consumer in the world. Underground mining is the main practice. In the process of deep mining, large amounts of low-temperature waste heat are available such as in the mine return air (MRA), mine water (MW), bathing waste water (BWW), etc. Without recycling, the low-temperature waste heat is discharged directly into the atmosphere or into the drainage system. The temperature range of the MRA is about 15-25°C, the relative humidity (RH) of the MRA is above 90 per cent, the temperature range of MW is about 18-20°C and the temperature of the BWW is about 30°C. All of the above parameters are relatively stable throughout the year, and thus MRA, MW and BWW are proper low-temperature heat sources for water source heat pump (WSHP) systems. The study aims to introduce the schemes for recycling the different waste heat sources and the relevant key equipment and technology of each waste heat recycle system; analyze the heat recovery performances of the MRA heat recovery technology; and compare the economies between the MRA heat recovery system and the traditional system.

Based on the WSHP system, heat and mass transfer efficiencies were calculated and analyzed, the outlet air velocity diffusion of the heat and mass transfer units and the parameters including air flow rate, the MRA’s dry bulb temperatures and wet bulb temperatures at inlet and outlet of MRA heat exchanger were tested. Then, it was assessed whether this system can be applied to an actual construction. An actual reconstructive project of MRA heat recovery system is taken as an example, where the cost-saving effects of heat recovery of mine waste heat sources system are analyzed.

Analysis of field test reveals that when heat transfer is stable, heat transfer capacity can be achieved: 957.6 kW in summer, 681 kW in winter and a large amount of heat was recycled. In an economic analysis, by comparing initial investment and 10 years’ operation cost with the traditional boiler and central air conditioning system, the results show that although the MRA system’s initial investment is high, this system can save CNY 6.26m in 10 years.

MRA has a large amount of air volume and temperature that is constant throughout the year, and hence is a good low-temperature heat source for the WSHP system. It can replace boiler heating in winter and central air conditioning refrigeration in summer. The study reveals that this technology is feasible, and has good prospects for development.

Due to the high demand of concrete, significant volume of natural resources is required, including virgin aggregates. Many studies have shown that the production of concrete has one of the highest CO₂ levels. Although efforts are in place to recycle, enormous effects on landfill and the wider environment remain. Research has suggested the importance of reusing construction and demolition waste such as aggregate for use in recycled concrete. However, robust construction and demolition waste reduction strategies are required. There have been numerous researches on the use of recycled concrete and its management in the construction industry. This paper further consolidates this position.

This paper exhibits the barriers and benefits of using recycled aggregates for construction industry. This is achieved via reviewing the current construction and demolition waste reduction strategies used mainly in three countries: the UK, Australia and Japan. These countries were selected since they seemingly have similar construction industry and environment. Subsequently, evolving barriers and benefits of using recycled aggregates for construction industry are also reviewed and discussed. And to support such focus, robust construction and demolition waste reduction strategies will be advocated.

The findings are summarized as follows. The recycling construction and demolition waste could have a positive net benefit compared to the procurement and production of virgin aggregate materials with the same properties. This is not only financially beneficial but also environmentally viable, as fewer resources would be required to produce the same aggregate material. There are effective ways to achieve a high recycle rate target, as demonstrated by Japan. The implementation of a similar recycling process could be implemented globally to achieve a more effective recycle rate through the help of governments at all levels. By creating awareness about the financial and environmental benefits of using recycled aggregate products, large recycling companies can be also enticed to follow suit.

The findings from this paper can ultimately support the construction industry to further consolidate and advocate the use of recycled aggregates.

To achieve the research aim, this paper reviews some of the main sustainability factors of recycled aggregates (including coarse and fine aggregates) and provides comparison to virgin aggregates.

This paper aims to describe a solution for cyclonic flue dust recycling based on the example of ferrochromium producers in Kazakhstan. It includes environmental improvement, which can be assessed in detail based on LCA after the development of a feasibility study of such a proposal.

Three pyrometallurgical recycling approaches should be achieved. The first approach is reduction smelting of fine waste in a direct current arc furnace without preliminary agglomeration. The second is reduction smelting of agglomerated waste in a submerged arc furnace, and the third is processing of agglomerated waste with liquid cast iron. The last approach facilitates the reactions of metal oxide reduction by carbon and silicon from the iron with a corresponding decrease in energy and auxiliary material consumption.

Valuable material can be produced from ferrochromium dust waste using environmentally friendly technology, including electric furnaces that can operate in SAF regimes and a simple plasma high‐power DC reactor operating under a neutral or reducing atmosphere. Finally, the investigation of waste recycling has developed a novel approach that facilitates metal oxide reduction and provides low energy and auxiliary materials consumption.

Research into the treatment of flue dust generated in the ferrochromium industry is needed to solve environmental problems not only in Kazakhstan but also in all ferrochromium plants in the world.

The three proposed pyrometallurgical recycling approaches should be achieved on a large scale.

The paper attempts to frame the challenge of managing the transition to a sustainable economy by way of a conceptual model consisting of a zero-footprint regulatory regime and a sustainability fund.

A conceptual model of the sustainable industrial revolution has been developed based on the learnings from industries such as originators (mining), farming, pharmaceuticals, pesticides and chemicals and long-lasting artefacts against an overall perspective.

It is suggested to have an institutional structural mechanism in place to ensure that footprint is minimized through recycling including refurbishing, resale or transformation. This includes management of recycling businesses through execution of a zero-waste regulatory regime that will build and use a sustainability fund.

The limitations of the paper are arising out of the topic being an issue of gigantic proportions with immense complexity. An attempt has been made to bring out the inescapability and the imperative of a sustainable industrial revolution.

This paper presents practical aspects such as collusion between trash and recycling businesses, land use and social aspects of criticality of public support. If implemented, the suggested model can make a paradigm shift in the way firms, industry and governments can handle the challenge of sustainability.

The value of this conceptual paper lies in an attempt to extend the learning organization framework to the concept of a regulatory model for sustainability that is not limited to the definition of a firm but stands extended to industries and to the economics, land use and demographics of the planet.

This paper presents a systematic literature review of the various aspects of reverse logistics (RL) and closed-loop supply chains (CLSC) in implementing and achieving circular economy (CE) motives. CE is identified as a method of embracing imperishability into the economic structure, helping shift from a linear to a condition leading to ecological and social benefits.

Systematic literature was used to review a total of 80 peer-reviewed articles are included in the study and covers different concepts related to the implementation of CE, such as cost-saving, network design, sustainable RL, waste management and extended producer responsibility.

The findings reveal that the research in the domain is in a growing phase, and in recent years, a lot of attention has been given by researchers across the globe. However, further research is required in crucial areas for the adoption of CE, such as retail reverse logistics, pharmaceutical industries and resource recycling industry.

The study discusses the business needs and solutions for industries. Key enablers and barriers are listed along with the main activities involved in each sector in CLSC. Managers can design a pathway to decide which lever to use to overcome a particular challenge.

The work contributes theoretically by developing research themes in RL and CLSC practices applied to CE. It also provides theoretical and practical implications of the study, which can be used as a signboard for further research.