Within the rural electrification literature, only a few studies make remarks on the relation between the concept of circular economy and the effects of electricity in these marginalised communities. In contrast, most electrification studies describe the marginalised nature of the rural contexts in the Global South, leaving the dialogue about efficient technologies and economic models typical of CE literature outside their main discussion. The few articles to mention circularity seem to adopt a vision similar to the Global North, reproducing thoughts on the need to implement more efficient technologies, effective policies and financing schemes to promote the "sharing economy", yet under an overwhelming number of difficulties for its implementation [1, 2]. However, there is also a literature critical of CE primarily inside the Global North, which argues that circularity emerges as a theoretically, practically and ideologically questionable notion [3, 4]. These analyses argue that although some initiatives may lead to the decoupling of economic growth from resource extraction, it does not necessarily mean reducing the extraction rate or, for practical use, meeting environmental needs. It is also reasoned that CE can create an inevitable accumulation of individual wealth and exacerbate the informal economy and the precariousness of work [4, 5]. Nevertheless, few reflections on CE and community development emerge from the circumstances of marginalised communities in the global south [6]. Hence, there is not enough evidence to refute or support the idea that the circular economy can meet social and environmental goals compatible with the development needs in these contexts. The aim of this research is to discuss aspects of circularity in the perspective of marginalised communities without electrification in Southeast Asia. Building upon previous analyses of changes in daily activities experienced from introducing renewable solar systems in 2019-2022, we will address how compatible CE notions could be to promote sustainable development in rural communities in The Philippines and Malaysia and the relevance of the raised criticisms to CE. The investigation will be based on the analysis of interviews with members of the community.

References:

[1] Desmond, P., & Asamba, M. (2019). Accelerating the transition to a circular economy in Africa: Case studies from Kenya and South Africa. In The Circular Economy and the Global South (pp. 152-172). Routledge.

[2] Bhattacharyya, S. C., & Palit, D. (2016). Mini-grid based off-grid electrification to enhance electricity access in developing countries: What policies may be required?. Energy Policy, 94, 166-178.

[3] Corvellec, H., Stowell, A. F., & Johansson, N. (2022). Critiques of the circular economy. Journal of Industrial Ecology, 26(2), 421-432.

[4] Hart, J., & Pomponi, F. (2021). A circular economy: where will it take us?. Circular Economy and Sustainability, 1(1), 127-141.

[5] Fevrier, K. (2022). Informal Waste Recycling Economies in the Global South and the Chimera of Green Capitalism. Antipode.

[6] Kinally, C., Antonanzas-Torres, F., Podd, F., & Gallego-Schmid, A. (2022). Off-grid solar waste in sub-Saharan Africa: Market dynamics, barriers to sustainability, and circular economy solutions. Energy for Sustainable Development, 70, 415-429.

How to cite: Cravioto, J. and Ohgaki, H.: Can the circular economy be relevant for rural development? Insights from communities without electricity in South-East Asia, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-11487, https://doi.org/10.5194/egusphere-egu23-11487, 2023.

Fossil and mineral raw materials enable sustainable development and undermine it, causing unintended and detrimental environmental and social impacts via extraction and production processes. The reliance of humans on minerals has led to wide-scale mining and depletion of resources. In this study, we analyse how consumer demand in the European Union drives environmental and social impacts in mining sectors worldwide. We employ multi-regional input-output analysis to quantify positive (i.e., income, female and male employment) and negative (greenhouse gas emissions, accidents at work, and modern slavery) impacts of mining in raw material sectors, as indicators of the UN Sustainable Development Goals. We trace these environmen­tal and social impacts across the EU’s trading partners to identify sectors and regions as hotspots of international spillovers embodied in the EU’s consumer demand and find that these hotspots are wide-ranging in all continents. We estimate that across all sectors, EU’s consumption is associated with about 4200 cases of fatal accidents at work and 1.2 million cases of modern slavery annually. Raw material supply chains are respectively responsible for 5% and 3% of these totals, but also 14% of imported GHG emissions. These impacts take place primarily in Central Asia and the Asia Pacific as well as Africa. Our results underline the need for further reforms in mining industries and trade policies to eradicate modern slavery and other adverse social and environmental impacts and to implement safe workplaces for workers. Our results also highlight the need for transitioning to circularity in global supply chains for addressing the climate crisis.

How to cite: Malik, A., Lafortune, G., Mora, C., Carter, S., and Lenzen, M.: Social and environmental impacts associated with fossil and mineral supply chains - a quantitative assessment of the EU’s international spillover effects, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-1435, https://doi.org/10.5194/egusphere-egu23-1435, 2023.

Concrete is considered the most anthropogenic material used in the construction sector worldwide. It is associated with consuming massive amounts of energy and the depletion of natural resources, based on the increasing Egyptian urban expansion by establishing new cities to face the population growth challenges and achieve the national development strategy. The importance of applying the Circular Economy (CE) for concrete materials in the building sector became a robust key for reducing conventional concrete (CC) materials and addressing the building materials' future challenges. This study investigates the benefits of Green Concrete (GC) materials and their potential for supporting the principles of achieving circularity for concrete materials in the Egyptian building sector. Furthermore, develop a conceptual framework for using GC from the building scale perspective in two new Egyptian cities. The study attempts to answer how GC materials help achieve a circular economy and the potential benefits of integrating different CE strategies for using GC in the Egyptian building sector. The evidence-based solutions (EBS) methodology was used for collecting and analyzing data for assessing the environmental impacts based on reducing the natural resources consumption, recycling, and reusing waste products in the Egyptian building sector. Case studies are used to provide in-depth insights into the practicalities of GC. Applying the before-and-after (BAA) technique for two building models highlights the challenges and opportunities for substituting CC with GC to assess the interactive factors for achieving CE and applying sustainability. The results showed valuable insights into the potential for using GC to support the CE and have a strong ability to reduce natural resources consumption and construction waste stream, which leads to close the loop and achieving circularity in the Egyptian building sector, and recommended that Design for Recycling (DfR) strategy is the most need for improving the using of GC in the building sectors.

Keywords, Green Concrete, Circular Economy, Evidence-based Solutions, Egyptian building sector

How to cite: Marey, H., Kozma, G., and Szabó, G.: Towards Circular Economy by Using Green Concrete in the Egyptian Building Sector, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-4293, https://doi.org/10.5194/egusphere-egu23-4293, 2023.

The management and final disposal of waste containing radioactive elements is currently challenging in many countries due to the large volumes and their potential radiological risk. A promising alternative is the re-use to reduce the amount of waste to be disposed and to provide additional profit to the companies that generates this residue. This can be the case of fluorite sludge produced after the manufacturing of dicalcium phosphate. In this study, the initial stage of waste characterisation of fluorite sludge from two industrial sites, one active in Flix (NE Spain) and another one consisting of legacy ponds and stockpiles at El Hondón, in SE Spain, is reported. Fluorite sludge consists of 40-60% of CaF₂, which precipitates during the reaction between fluorapatite (main component of phosphorite raw material) and HCl. This fluorite is very fine grained, with most particle sizes below 5 microns, and contains significant amounts of REEs, mainly Y, La, Ce and Nd, (0.2wt%, 800 ppm, 600 ppm and 300 respectively), especially in the sludge that precipitated in the reaction tanks. Concentration of the other REEs vary from 18 ppm to 167 ppm. Prices for the top grade REEs are high at the moment, and with time, as the reserves become scarcer, the prices will grow even more. Also, fluorite concentrate can be a valuable commodity. Taking into account the large amounts of disposed waste in both sites, and the concentrations of REEs, their recovery can be a great opportunity to reduce the amount of waste to be managed, and to provide new sources for these critical raw materials. So, current investigations are focused on cost-effective methodologies of fluorite separation and concentration and REEs extraction. 

How to cite: Grandia, F. and Plachciak, M.: Recovery of rare earth elements from fluorite sludges from dicalcium phosphate industry, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-7985, https://doi.org/10.5194/egusphere-egu23-7985, 2023.

Increasing volumes of electrical and electronic waste (e-waste) demand for innovative and efficient recycling solutions to keep materials in the process/recovery loop. The recovery percentage and quality of resulting recycling products depend fundamentally on the ability to accurately identify the constituents of the e-waste stream. Traditionally, recycling is based on sequential enrichment of target components and reduction of hazardous substances with random sampling from an assumed homogeneous mass. E-waste represents in this context a highly heterogeneous, complex waste composed of a variety of different compounds required to meet the high diversity of functional requirements. Tailored sensor-systems can achieve a successful extraction of several target materials such as precious metals or specific polymers, but reach their limits for many low concentrated, critical raw materials. Hazardous substances and additives (e.g. dark pigments in polymers, poisonous oxides) are difficult to remove from the stream and induce risks of down-cycling, quality loss and reduced acceptance of recycling products. 

HELIOS lab is an agile solution for non-invasive sensing applied to complex recycling streams such as e-waste suited for conveyor belt operations. We employ hyperspectral imaging technology for the fast and spatially resolved acquisition of information associated with physical material properties. Multiple cameras allow for combining reflectance information from the visible to midwave-infrared wavelengths range to differentiate material classes. Fast data processing routines then allow for generating first order material maps. Such maps suffice for well defined, relatively homogeneous material streams but not  for a precise and accurate sorting and process monitoring. For efficient e-waste recycling, further information is required to enhance the component identification, particularly for certain critical raw materials and complex compounds. We suggest additional validation cycles to refine the initial mapping. Several sensors traditionally used for bulk measurements deliver the solution for detailed point validation. Here, Raman spectroscopy, XRF and LIBS provide the needed complementary data for the identification of a wide range of critical raw materials and hazardous e-waste components. Additionally, our in-house developed laser-induced fluorescence (LiF) system contributes a scanning solution for rare-earth element mapping. However, those validation sensors are very sensitive to signal integration times, power and focus distances. We showcase two examples for a combination of Raman spectroscopy and LiF with hyperspectral imaging technology to extract meaningful information from typical e-waste streams such as printed circuit boards and electrolysers in a conveyor belt setting. We discuss the main challenges and give an outlook on additional development needs that we will address in our HELIOS lab in the frame of the EU funded projects RAMSES and inSPECtor (EIT RawMaterials), and the BMBF funded projects High-speed imaging, InfraDatRec, Digisort and H2Giga.

How to cite: Fuchs, M. C., Lorenz, S., Madriz Diaz, Y. C., Abend, T., Shaik Fareedh, J., de Lima Ribeiro, A., Arbash, E., Rasti, B., Beyer, J., Röder, C., Schüler, N., Dornich, K., Heitmann, J., and Gloaguen, R.: How can agile sensing improve recycling stream characterisation and monitoring for e-waste? - news from the HELIOS lab, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-12298, https://doi.org/10.5194/egusphere-egu23-12298, 2023.

Plastics are major components of waste from electrical and electronic equipment (WEEE, or e-waste) accounting for up to 25% of annual e-waste production. The composition of such plastics varies greatly according to their original function in the electrical and electronic equipment, and may include additives such as dark pigments and brominated compounds. With WEEE becoming the fastest growing waste stream in recent years, the recycling of polymers became a keystone for waste management and closing material loops. Closing the loops in material life cycles requires that type-pure plastics are obtained at the end of the recycling chain. Accordingly, the identification of polymers prior to their sorting in recycling lines is a fundamental prerequisite.

Here, we explore how an innovative combination of optical sensors can aid the identification of plastics in the plastic recycling environment in order to increase recovery rates and quality of recyclates.

We have selected 23 different polymer samples, representative of the plastic types commonly found in e-waste. We investigated the sequential use of high-speed hyperspectral imaging (HSI) and Raman spectroscopic sensors for digitalization of the waste stream and identification of polymer composition. HSI-reflectance sensors in the short-wave infrared (HSI-SWIR, Specim AisaFenix, 970 - 2500 nm) domain acquired simultaneously spatial and spectral information, allowing for mapping and initial identification of certain transparent and light-coloured polymers (PE, PP, PET, and PC). Raman measurements, collected at specific points and with integration times < 2 seconds, allowed for specific identification of all polymer samples, including black plastics. The use of both sensor technologies on conveyor belts has the potential to fully characterise the WEEE plastics stream, generating identification signals serving as input for sorting machines or simulation models. The combination of latest high-speed sensors and data processing opens many further fields of material stream characterisation and monitoring, which come with high data acquisition rates and volumes. 

Consequently, a smart selection of sensors along with a tailored and learning data processing will be key to innovations towards more complex and agile recycling processes. In this context, our multi-sensor solution focuses on a combination of advantages from HSI and Raman spectroscopy aided by efficient data integration (‘RAMSES-4-CE’ project, supported by the EU EIT Raw Materials).

How to cite: de Lima Ribeiro, A., Fuchs, M., Röder, C., Schüler, N., Lorenz, S., Sheng, Y. X., Heitmann, J., Dornich, K., and Gloaguen, R.: Potential of optical sensors for polymer type identification in e-waste recycling streams, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-12643, https://doi.org/10.5194/egusphere-egu23-12643, 2023.

How to cite: Jarosz, K., Kasina, M., Rozpądek, P., and Ważny, R.: Bioleaching by endophytic microorganisms as a method of element recovery from sewage sludge incineration ash, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-14785, https://doi.org/10.5194/egusphere-egu23-14785, 2023.

The by-products of abattoirs may become valuable resources for nutrient recycling and energy generation by including pyrolysis and biogas production in the value creation chain. This study investigated the potential of bone chars as sorbents for ammonium in order to produce a soil amendment useful for fertilizing purposes. Ammonium enriched from the digestate by membrane distillation or from pure ammonium sulphate solutions accommodated the nitrogen sorption to the bone chars. The plant availability of the sorbed nitrogen was studied by a standardized short-term plant test with rye (Secale cereale L.).

The results showed that ammonium, both from biogas digestate of the abattoir and from pure salt solutions, could be sorbed successfully to the bone chars post-pyrolysis and increased the nitrogen concentration of the chars (1.6±0.3 %) by 0.2-0.4 %. This additional nitrogen was desorbed easily and supported plant growth (+17 to +37 %) and plant nitrogen uptake (+19 to 74 %). The sorption of ammonium to the bone chars had a positive effect on the reversal of pure bone char phytotoxicity and on nitrogen availability. In summary, this study showed that abattoir wastes are useful pyrolysis input materials to produce bone chars and to use biogas digestates as ammonium source for nitrogen sorption to the chars. This innovation offers the possibility to produce nitrogen-enriched bone chars as a new type of fertilizer that upgrades the known value of bone char as phosphorus fertilizer by an additional nitrogen fertilizer effect. The study also shows that abattoirs, too, may become contributors to circular economy by facilitating the recovery of nitrogen and phosphorus.

How to cite: Soja, G., Sörensen, A., Drosg, B., Gabauer, W., Schumergruber, A., Dunst, G., Meitner, D., Guillen, E., and Pfeifer, C.: Recycling of Nitrogen and Phosphorus with Bone Biochar and Biogas Digestates from Abattoir Residues, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-8863, https://doi.org/10.5194/egusphere-egu23-8863, 2023.

A large amount of agricultural byproducts and animal husbandry waste have been produced due to the inevitable agricultural practice for human survival. The utilization of agricultural and animal husbandry residues in waste-to-energy technologies has become an eye-catching issue over years because of the concept of circular economy for sustainable development. These biogenic residues possess a high content of organic carbon such as sugars, proteins, and lipids and are being dumped into landfills or incinerated, causing severe environmental challenges and the waste of available resources. Anaerobic digestion (AD) provides a sustainable route for resource circular utilization in agriculture and husbandry waste. The dry anaerobic digestion process is adopted to treat biogenic waste including outer leaves of cabbage (C), litter (L), and pig manure (PM) in the present study. Different from the main target of past studies to enhance biomethane production, this study aimed to transform the waste into saccharides and organic acids which are the intermediates in AD processes (i.e. hydrolysis and acidogenesis phases) and can be further refined or utilized in various industries. For instance, succinic acid of high economic benefits can be obtained through transforming AD digestate. Hence, Saccharomyces cerevisiae was chosen as the microbial inoculum due to its non-gas-generating characteristic. The results of batch AD experiments for 35 days showed that the optimum feedstock mass mixture ratios are C:L = 2:1, C:L = 3:1, C:PM = 2:1, and C:PM = 3:1 since the observation of more saccharides formation. Moreover, the optimal feedstock-to-inoculum ratio (F/I ratio) is 1:1 and the best AD operation temperature is 50℃. The substance flow analysis was established based on the measurement of key AD products (i.e. saccharides, organic acids, CH₄, CO₂, and digestate). The batch experiments was scaled up to the 10L continuously-stirred reaction tank to determine the feasibility of in situ AD practice. In comparison to the traditional way to deal with agriculture and husbandry waste, AD is promising to be a valorized treatment to convert waste into reusable bioproducts which enables economic and environmental benefits to realize the concept of the circular economy.

How to cite: Lee, Y.-Y. and Fan, C.: Biogenic waste transformation into resources through anaerobic digestion, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-2198, https://doi.org/10.5194/egusphere-egu23-2198, 2023.