Material Streams Research Articles

Spectral Characterization of Battery Components from Li-Ion Battery Recycling Processes

Considering the increasing demand for Li-ion batteries, there is a need for sophisticated recycling strategies with both high recovery rates and low costs. Applying optical sensors for automating component detection is a very promising approach because of the non-contact, real-time process monitoring and the potential for complete digitization of mechanical sorting processes. In this work, mm-scale particles from shredded end-of-life Li-ion batteries are investigated by five different reflectance sensors, and a range from the visible to long-wave infrared is covered to determine the ideal detection window for major component identification as relevant input signals to sorting technologies. Based on the characterization, a spectral library including Al, Cu, separator foil, inlay foil, and plastic splinters was created, and the visible to near-infrared range (400–1000 nm) was identified as the most suitable spectral range to reliably discriminate between Al, Cu, and other battery components in the recycling material stream of interest. The evaluation of the different sensor types outlines that only imaging sensors meet the requirements of recycling stream monitoring and can deliver sufficient signal quality for subsequent mechanical sorting controls. Requirements for the setup parameters were discussed leading to the setup recommendation of a fast snapshot camera with a sufficiently high spectral resolution and signal-to-noise ratio.

Studying Flotation of Gold Microdispersions with Carrier Minerals and Pulp Aeration with a Steam–Air Mixture

This work is aimed at obtaining new knowledge in the field of interactions of polydisperse hydrophobic surfaces in order to increase the extraction of mineral microdispersions via flotation. The effect of high velocity and the probability of aggregating fine particles with large ones are used to increase the extraction of finely dispersed gold in this work. Large particles act as carrier minerals, which are intentionally introduced into a pulp. The novelty of this work lies in the fact that a rougher concentrate is used as the carrier mineral. For this purpose, it is isolated from three parallel pulp streams by mixing the rougher concentrate, isolated from the first stream of raw materials, with an initial feed of the second stream; accordingly, the rougher concentrate of the second stream is mixed with the initial feed of the third stream, and the finished rougher concentrate is obtained. In this mode of extracting the rougher concentrate, the content of the extracted metal increases from stream to stream, which contributes to the growth in its content in the end product. Moreover, in order to supplement forces involved in the separation of minerals with surface forces of structural origin in the third flotation stream, the pulp is aerated for a short time (about 15%–25% of the total) with air bubbles filled with a heat carrier, i.e., hot water vapor. Within this accepted flotation method, the influence that the surface currents occurring in the wetting film have on its thinning and breakthrough kinetics is proposed to be in the form of a correction to a length of a liquid slip in the hydrophobic gap. The value of the correction is expressed as a fraction of the limiting thickness of the wetting film, determined by the condition of its thickness invariability when the streams are equal in an interphase gap: outflowing (due to an action of the downforce) and inflowing (Marangoni flows and a thermo-osmotic stream). Gold flotation experiments are performed on samples of gold-bearing ore obtained from two deposits with conditions that simulate a continuous process. Technological advantages of this developed scheme and a flotation mode of gold microdispersions are shown in comparison with the basic technology. The purpose of this work is to conduct comparative tests on the basic and developed technologies using samples of gold-bearing ore obtained from the Natalka and Olimpiada deposits. Through the use of the developed technology, an increase in gold extraction of 7.99% and in concentrate quality (from 5.09 to 100.3 g/t) is achieved when the yield of the concentrate decreases from 1.86 to 1.30%, which reduces the costs associated with its expensive metallurgical processing.

Optimization of the vinyl-monochloride recovery process for the reduction of costs and environmental impact

Reducing environmental impacts in the production processes is the focus of large industries. In the PVC production process, the loss of vinyl monochloride (VCM) through an incineration stream of inert materials is a point of attention due to emission of greenhouse gases. VCM is lost as part of the stream of uncondensed gases from the VCM recovery unit. The optimization of the VCM recovery process was carried out by modelling the industrial system and running it using a process simulator. The unit model and simulation results have been verified through plant operating data. Sensitivity analyses were performed to identify which independent variables improved the VCM condensation rate. Based on plant operating experience, three independent variables were selected and their influence on the VCM recovery flow rate was verified: pressure, composition of the input stream and utility water flow rate. After the sensitivity analysis, the plant operating pressure was selected for optimization, resulting in the additional quarterly recovery of 7.5 tons of VCM and a reduction of more than 5 tons of natural gas fuel, that is, an annual reduction of 23 tons of fuel, which represents 53 tons of CO2eq. Overall, the annual savings amount to US$15,000, US$1,060 by reducing the consumption of fuel gas alone. Therefore, by ensuring greater VCM recovery, competitiveness improves by reducing production costs, and greenhouse gas emissions are reduced due to the decrease in gas incineration.

Holistic Assessment of Decarbonization Pathways of Energy-Intensive Industries Based on Exergy Analysis

The decarbonization of the industrial sector plays a crucial role in a successful energy transition. This transformation is very costly and complex, as many of the existing production processes and plants will have to be partially or completely replaced to reduce carbon dioxide (CO2) emissions. This raises questions about how significant reductions in CO2 emissions resulting from decarbonization will affect the use of resources to produce a certain product and the overall value of sustainability. This article considers the relationship between CO2 reduction and the impact on the resource efficiency of an industrial production process. For this purpose, a methodology was developed that holistically assesses the decarbonization pathway of an industrial sector. This holistic assessment takes into account the energy carriers, raw materials, and auxiliary and construction materials used for the operation and building of the significant plant components and summarizes them as a total use of resources. For this purpose, the use of resources is represented by the thermodynamic quantity exergy, which takes into account both the energy and material components of a production process. The energy and material streams in a production process are balanced by applying exergetic analysis. This methodology is used for current state-of-the-art and future decarbonized production processes in order to quantify the effects of the decarbonization process. By comparing the calculated resource efficiencies, the thermodynamic impact on the sustainability of decarbonization paths can be set in relation to the amount of CO2 saved. For validation, the developed methodology is applied to a conventional and a decarbonized ammonia production process. The conventional production route represents the production of ammonia by methane steam reforming, and the decarbonized production route is represented by synthesis gas production via water electrolysis and an air separation unit. The resource efficiency of the conventional ammonia production route, taking into account the energy sources, raw materials, construction materials, and auxiliary materials used, is 59%, producing a total of 1539 kg of CO2 emissions per ton of ammonia. The decarbonized process has a resource efficiency of 45%, while no CO2 emissions are produced in this manufacturing process. This means that the decarbonization of the production process reduces resource efficiency by 14%. In relation to the reduced amount of CO2, specific resource efficiency decreases by 9.09%/tCO2. The decline in resource efficiency is mainly due to the high level of heat and energy recovery in the conventional process and the very electricity-intensive hydrogen production in the decarbonized production process.

Techno-economic analysis of a circular microalgal approach for enhanced wastewater treatment and resource recovery in Northern Portugal

Microalgae culturing in municipal wastewater treatment plants (WWTP) can be a solution to lower the effluent's nitrogen and phosphorus concentrations to comply with the new legislative limits. Microalgae can also promote a circular approach to WWTP by recycling material streams and reducing the energetic consumption of the treatment process. This study aims to perform a techno-economic assessment of the integration of microalgae culture (Chlorella vulgaris) as tertiary treatment at a WWTP in northern Portugal. This evaluation took into account information collected from the specific WWTP under study as well as relevant literature for each stage of the process. The major system flows: (i) a 7377 m3 d−1 treated water flow (ii) the treatment of 107,736 kg d −1 of sludge; (iii) a biosolids soil amendment production of 7580 kg d−1; and (iv) 10,874 kW h d−1 energy for self-consumption. In this work, the integration of microalgae in WWTP achieved yearly gross earnings of approximately 619,100 €.

Novel ASU–LAES system with flexible energy release: Analysis of cycle performance, economics, and peak shaving advantages

This study uses a cryogenic distillation method air separation unit (ASU) coupled with liquid air energy storage (LAES) to improve the round-trip efficiency and reduce the initial investment of LAES. We propose an integrated system (ASU–LAES–DER) with different ways of energy release. In the novel system, the liquid air can be reheated and expanded to produce additional power, or the liquid air energy stream and part of the material stream can be used for ASU distillation to produce power saving effects. This novel integration allows the ASU to have load regulation capability and facilitates the implementation of demand-side power management. Furthermore, the flexible and efficient energy release methods improve the energy efficiency and economic value of LAES. The comprehensive round-trip efficiency of the system can reach 52.1%–69.2 % with a payback period of 3.25–6.72 years. The peaking index is used to analyze the peak-to-valley load transfer capability of the novel system. Results show that the peaking index ranges from 25.5 MW to 50.1 MW at different scales, indicating that the system can be used as an important grid peaking unit when applied on a large scale.

Enabling the recycling of metals from the shredder light fraction derived from waste of electrical and electronic equipment via continuous pyrolysis process

The surge in Waste Electrical and Electronic Equipment (WEEE) generation, reaching 53.6 million metric tons (Mt) in 2019, demands efficient recycling solutions. This study focuses on the Shredder Light Fraction (SLF), a material stream derived from the mechanical pre-processing of WEEE, which is considered “municipal waste”. SLF constitutes 4.2% of the output material and is rich in metals like copper, tin, lead, zinc, silver, and gold.Pyrolysis treatment was applied to SLF, enabling recyclability. Both batch and continuous setups were employed for materials flow analysis and technical evaluation of the resource potential. The research evaluates the impact of pyrolysis technology on solid fraction metal content and pyrolysis gas/oil energy potential. Scaling up the process addressed material heterogeneity and increased the reliability of the obtained results.An innovative pyrometallurgical extraction approach was suggested, to recover valuable metals in SLF which otherwise could be lost via energy recovery methods. The resulting solid product after pyrolysis showed enriched concentrations of copper, zinc, lead, and precious metals with concentrations acceptable for industrial use. Additionally, it displayed reduced mass and diminished hazardous constituents.The non-condensable gas, rich in hydrogen, carbon monoxide, and methane, exhibited potential as an alternative energy source or reducing agent in the metallurgical sector.This research advances metal recycling from SLF, offering valuable insights for environmental impact mitigation as waste was transformed into a valuable by-product for potential use in the copper industry.

92 Implications of Processing and Handling on the Functionality of Animal Derived Products for Pet Foods

Abstract The pet food industry has been closely tied to the livestock, meat, and rendering industries by using materials left over from human food production. Rendered animal fats are an excellent source of dietary fat and provide enhanced palatability when used to enrobe dry pet food. Mechanically deboned meat, viscera, and rendered protein meals are often utilized as a primary source of highly digestible, well-balanced proteins and vitamins and minerals. Although these products can be easily transported and stored, they are susceptible to oxidative and microbial degradation. Antioxidants and antimicrobials aid in preserving the quality of these ingredients but are only part of the solution. How these ingredients are produced, stored, and handled can impact quality. It is important to remember that this raw material stream starts with livestock management practices. Specifically, changes in nutritional practices in the livestock industry can impact the characteristics of the products used for both human and pet foods, especially when considering poultry and pork products. Demands by consumers in the meat industry have resulted in the popularity of vegetarian diets. For example, decreased amounts of rendered animal protein meals in diets fed to chickens and turkeys have shifted towards more unsaturated fats, ultimately decreasing oxidative stability. Handling animal products throughout their supply chain can also affect product quality and potential usability. After harvest, raw material is often transported and processed by two or more different facilities before arriving at the pet food manufacturer. At the meat and rendering facilities, food safety hurdles along with processing aids can limit biogenic amine or free fatty acid formation. Once oxidation and microbial degradation occur, they cannot be reversed. Therefore, addressing food safety or oxidation control upstream in the supply chain is critical. Since each facility is unique in how co-products are processed and handled, understanding how different antioxidant blends and how and where these are applied all impact final product quality; this carries through to the quality and shelf life of the pet food diet these ingredients are intended for. With most pet foods targeting 18 months to 2 years of shelf life, starting with high-quality ingredients is key to achieving these goals. The human food, rendering, and pet food industries remain closely tied together. Trends within the meat and rendering industry result in the potential for these ingredients to be more susceptible to quality and functionality changes. The pet food industry must continue to monitor and evaluate changes in livestock production practices and product handling. Proactive management of these ingredients throughout the supply chain can ensure that these ingredients remain high-quality, cost-effective ingredients for pet food.

Mass determination and model prediction of retired blades from wind turbine repowering or dismantling using a GIS database

Existing estimations of waste from wind energy infrastructure that is headed for, flowing through, or having reached the terminus of various post-processing pathways have primarily relied on reported capacity to extrapolate the material weight of turbine components. This data can be used to project future streams of composite blade material coming from wind farm repowering and decommissioning and inform policies to optimize or improve certain blade End of Life (EoL) options. However, rated capacity alone is insufficient to quantify or characterize the dynamics of US wind fleet retirement, since turbines are often repowered with new blades but their capacity remains the same. This research demonstrates an alternative method, comparing various mass estimation techniques and identifying blade models that have been retired or are soon to enter waste pathways due to turbine repowering by spatiotemporal comparison of periodic versions of the United States Geological Survey (USGS) Wind Turbine Database (USWTDB). These analyses are used to compile a list of turbine and blade models that will be at the forefront of national repowering and decommissioning movements in the near future. Mass of future waste flows are totalled and can help inform protocols and frameworks for blade material EoL processes.

Insights into Circular Economy Potential of Lithium by System Dynamic Modelling of Material Streams

AbstractLithium is a key raw material for producing lithium‐ion batteries. This study applies system dynamics modelling to demonstrate the (1) global lithium demand in specific lithium applications from 2005 to 2050, (2) the adequacy of lithium reserves for future lithium demand, (3) lithium content of waste streams throughout lithium value chain and (4) potential of various circular strategies for answering to the rising lithium demand. According to the modelling results, the main lithium application is battery electric vehicle batteries (almost 60 % in 2023 to 80–90 % by 2050) with current battery chemistries. Without circular strategies, 75–85 % of lithium is wasted throughout the value chain. Circular strategies may reduce the waste considerably (7–47 %), but to maintain sustainable supply of lithium a stacking of multiple complementary circular strategies over the lithium value chain is required.

MAGNEX and PILCCU in Finland: deployment of CO2 mineralisation in circular economies

Two ongoing projects in Finland, MAGNEX (Viable magnesium ecosystem: exploiting Mg from magnesium silicates with carbon capture and utilization) and PILCCU (Piloting of ÅA CCU) aim at using CO2 mineralisation technology for the overlapping purposes of large-scale CO2 emissions mitigation and bringing several valuable material streams into circular economies, including construction. Of central importance are magnesium-based materials, such as magnesium carbonate hydrate (MCH), besides (amorphous) silica and several metallic species. On top of revenues from these, CO2 emissions mitigation lowers the financial penalty from CO2 emission rights under for example the European ETS. The ÅA process routes are stepwise processes based on extraction of magnesium (and other species) from serpentinite-containing mining tailings from Finland, followed by precipitation of metallic species, carbonation using a CO2 containing gas-stream (no separate capture step needed) and recovery of solvent salt, respectively. Several separation steps involve (ion-selective) membrane electrodialysis. Besides ongoing mapping and characterisation of Finnish rock resources as tailings or other side-streams at metal and mineral mines in Finland, the projects address public acceptance, legislation and other non-technical issues related to large-scale roll-out of this type of CCU technology.For the use of the solids, magnesium-based cement binders and plaster-like recipes are investigated as well as applications for the (amorphous) silica and other residues, including the use of MCH for cyclic thermal energy storage (TES). Special focus is on accelerating the carbonation step and the final outcome of MCH production, considering pressure (including supercritical CO2 levels), and the role of recoverable catalysts and other additives. The work receives funding from the Academy of Finland (2022-2025) and from Business Finland plus industry partners (2022-2024), respectively.

A Review of Top-Submerged Lance (TSL) Processing—Part I: Plant and Reactor Engineering

Part I of this series of papers focuses on plant and reactor engineering aspects of the TSL reactor technology. A general flowsheet is presented, while emphasis is given to the definition of different reactor zones in terms of fluid dynamics and occurring reactions. Then, the technical advantages of TSL processing, such as feed flexibility and high conversion rates (due to induced turbulence), low dust generation, and low fugitive emissions, are explained. In addition, the reactor is analyzed part by part, also taking into account patent literature, focusing on furnace design, settling furnaces for molten phase disengagement, feeding systems regarding input material streams such as concentrates and fuels, vessel cooling arrangements, off-gas system, and aspects associated with the refractory lining. Furthermore, specific focus is given to the centerpiece of the TSL reactor, i.e., the reactor lance. Associated developments have focused on establishing a slag coating to hinder lance wear, i.e., the development of cooling mechanisms (e.g., use of fluid-cooled lance and shroud arrangements), the increment of O2 enrichment within the incoming air stream, and influencing of fluid dynamics (e.g., O2 conversion at the lance tip, bubble formation, and bath splashing). Finally, comprehensive tables concerning process developments and commissioned TSL plants are provided thus concluding Part I of the review.

Exploring the intersection of Design and Biology in today’s industry.

This article examines the intersection of design and biology in today’s industry. The study is divided into two stages, with the first stage exploring the terminology and definitions associated with the commonly used term ‘biomaterial’ through a comprehensive search and qualitative analysis. The results suggest the need to reconsider the labelling of materials, moving away from the generic term ‘biomaterial’ towards more specific descriptors such as ‘biobased’, ‘biodegradable’, or ‘biomanufactured’. By enhancing the understanding and communication surrounding biological material streams, this study contributes to the field. Additionally, the study identifies that the focus lies more in the design process associated with these materials rather than their materiality alone, as exemplified by the four identified lenses: ‘origin’, ‘production’, ‘use’, and ‘end-of-life’. This aligns with the concept of ‘biodesign’, which aims to reestablish a synergistic relationship between mankind and nature. This resulted in the suggestion of a new biodesign model comprised of these four lenses. The findings of the first stage prompted the initiation of the ongoing second stage, which aims to uncover the motives and design processes underlying biodesign practices by conducting extensive expert interviews and qualitative analysis. The ultimate objective is to identify the gaps that impede the professional implementation of biodesign in today’s industry. The authors plan to publish the findings of this ongoing research in a future academic publication.

Collection and Processing of Roadside Grass Clippings: A Supply Chain Optimization Case Study for East Flanders

The paper focuses on secondary bio streams which are not captured efficiently in the value supply chain. Specifically, roadside grass clippings were chosen, based on their logistical optimization potential, direct feasibility, locality, biomass potential, and economic valorization value. The main objective is to determine how this secondary flow can be brought to the “factory gate”—through road transport and inland shipping—and at what cost per unit. To this end, various scenarios were developed for a case study in East Flanders, considering multiple combinations of first collection points, secondary collection points, and processing points. The result is a generically applicable Excel-based tool that combines these variations with a solution considering both inland waterways and road transport. These scenarios become valuable in applying the tool for grass clippings and optimizing this value chain located in East Flanders. The results show that reducing the number of collection points is favorable for the utilization of inland waterways, as it reduces costs related to transshipment. Nevertheless, unimodal road transport is still the most cost-effective method for transporting this secondary material stream from the collection point to the processing point. Consequently, a lower weight and a higher density will lead to lower costs, which eventually bottom out, due to regulations and conditions that must be met.

Biotechnological strategies to recover value from waste

The demand on especially clean energy metals is growing exponentially creating a clear need to diversify the metals supply. Metal recovery from various waste deposits could be one solution to provide needed metals for the society and at the same time reduce the environmental effects of waste. Bioleaching has been commercially applied for the recovery of valuable metals from sulfidic ores, tailings and metallurgical side streams. Bioleaching approaches are still at laboratory scale for other waste streams, such as waste incineration ash, metallurgical slags and electronic waste. Adapted bioleaching strategies have been suggested for industrial and consumer metal-containing waste streams to overcome the challenges with alkalinity, heterogeneity, toxic contents, and the lack of sulfur and iron source. Integration of bioleaching with other technologies as well as integration of target waste with other material streams is one means to improve the process performance to reach higher metal yields and kinetics. Bioleaching has shown potential to decrease energy consumption and carbon footprint compared to more conventional technologies in commercial scale, which increases its attractiveness as a future technology choice.

Influence of different discharge levels on the mechanical recycling efficiency of lithium-ion batteries

Prior to the mechanical processing, discharging is necessary to prevent hazards. While the discharging process, different phenomena can occur changing the characteristics of the functional units of LIB. This study reveals the influence on the mechanical recycling and the obtained material when different discharge levels are used for various cells differing in their cell chemistry. It shows that for different cells, for example, copper deposits happen on the cathode as well as active material deposits on the separator foil. These new properties deteriorate the black mass quality and show contamination of the products with other material streams. It is being tested whether established sub-processes are suitable. However, it becomes clear that further recycling steps (e.g. flotation, hydrometallurgy) can be influenced as well as their product quality and element specific yield.

Proliferation aspects of partitioning and transmutation (P&T) fuel cycles

Abstract. Nuclear fuel is usually irradiated once but sometimes twice (MOX fuel). This procedure leaves a huge amount of spent fuel. Spent fuel is highly radioactive for a long time. Deep geological repositories are considered the best option for final disposal of this high-level radioactive waste. However, no such repository has been put into operation yet. Several countries consider partitioning and transmutation (P&T) a possible alternative. In P&T nuclear fuel cycles, the spent nuclear fuel is chopped into pieces and separated into different material streams such as plutonium, uranium and minor actinides. This process is called partitioning. From plutonium and minor actinides, new fuel elements are fabricated and used in nuclear reactors. If the overall physical conditions there are favorable, most prominently the presence of a fast neutron spectrum, at least a part of the minor actinides is fissioned and thus transmuted into other, hopefully easier-to-handle, nuclides. Especially when looking at the ingestion-based radiotoxicity index, reduction in minor actinides in nuclear waste is beneficial and might ease the requirements for a final repository. There are several drawbacks when looking at the concept of P&T: among others, several irradiation cycles are needed because the transmutation efficiency is so low. The technology for the processing of the spent fuel, the fuel fabrication and the irradiation is far from commercially available, and it is not clear whether this level can be met at all. This presentation focuses on the proliferation risk posed by possible P&T fuel cycles. The nexus between civil and military use of nuclear technology is widely known. If new fuel cycles are implemented, they should be more proliferation-resistant and not less. This would not be true for P&T fuel cycles: they require a closed nuclear fuel cycle with far more advanced reprocessing than today. Fissile material contained in spent nuclear fuel is not sent to final disposal but is separated into its components, which must be made available separately before they can be recombined into new fuel elements. Besides plutonium, this also includes other transuranic elements of small critical mass. The radiation barrier, an essential protection against unauthorized access to fissile material that could be used for nuclear weapons, is no longer present. The handling of those materials requires special facilities to cope with the immense amount of heat and radiation of the fuel containing high fractions of minor actinides. In those facilities, fissile material fitting for military purposes could be handled as well. Even if thorough safeguards are in place, detailed accountancy of all materials is not possible. The quantities needed to build a nuclear weapon are small compared to the quantities that need to be handled in a commercial-sized P&T fuel cycle. P&T technology is a civil application which clearly strengthens military capabilities. It would be hard to argue why it should only be available to a trustworthy partner (whoever that might be). The implementation of P&T fuel cycles would thus increase the risk of unauthorized diversion of nuclear material, technology and knowledge.

Sustainability analysis of packaging waste management systems: A case study in the Romanian context

Packaging waste is an important waste stream being directly linked to any product or good that consumers buy, use and then discard. Beyond policies setting recycling and recovery targets and the usual waste indicators in terms of generation, collection and treatment, packaging waste should be analyzed from the sustainability perspective. For countries in which municipal solid waste management has modest performances and packaging waste is organized solely based on Extended Producer Responsibility principle, such as Romania, this type of analysis is even more significant. Starting with 2018 onwards, the legislative European framework have set stringent packaging waste recovery and recycling targets, however beyond their achievement, it is important to also check what is the mid-term impact on sustainability at the member states level. Firstly, the study investigates multiple data sources (Environmental Fund Administration-EFA, Eurostat and National Waste Management Plan) to have a complete overview on the packaging waste generation and technical performances. Secondly, the US EPA WARM methodology was selected to perform the analysis. The indicators set within the methodology are the main indicatives for the environmental impacts and the socio-economic aspects in the end of life management operations, namely: greenhouse gas emissions and energy use, together with number of full-time jobs, wages and taxes. Throughout 5 proposed scenarios, the impact of packaging waste quantities variations on the sustainability results could be observed. Irrespective of the scenario, when the overall packaging waste generated quantities are within 1.88 up to 2.14 million tons, the sustainability profile limits give results for environmental indicators within the following ranges: greenhouse gas emissions −3.75 × 106 ÷ −1.4 × 106 tons CO2e/year, energy use −2.9 × 107 ÷ −1.1 × 107 GJ/year, social indicator: 5823–14368 full time jobs and economic indicators: 328 × 106 ÷ 692 × 106 US $/year in wages and 56.7 × 106 ÷ 136.7 × 106 US $/year in taxes. Beside the overall packaging waste sustainability profiles, specific packaging waste material streams, namely polyethylene terephthalate (PET) and aluminium sustainability profiles were obtained. For the entire packaging waste system, compared with the other scenarios, the sustainability profile for the EFA scenario has indicated the lowest environmental impact and the highest positive impact for the socio-economic indicators (with 2018 registering the best results). For both PET and aluminium packaging waste systems, in the EFA scenario, 2019 has been the year with the lowest performance (highest environmental impact and lowest values for the socio-economic indicators).

Enforced carbonation of cementitious materials

CO2 mineralization of cement materials utilizes reaction of calcium or magnesium with carbonate ions forming insoluble carbonates. Recent research has demonstrated that this process is applicable in several favorable ways at different stages of the concrete life cycle. This review focusses on the application of carbonation technologies to valorize the industrial material streams related to cement: recycled concrete paste, steel slags and fly ashes. These technologies enable CO2 sequestration and production of a new type of pozzolan. Different approaches and technologies for carbonation are discussed along with the associated reaction mechanisms for the relevant phase assemblages. Reactivity and applications of the carbonated materials as pozzolanic additives are also addressed. Enforced carbonation of the industrial materials can be conducted at ambient temperature and pressure, achieving high degrees of CO2 sequestration. The usage of the carbonated materials as supplementary cementitious materials makes an important contribution to the circularity in building industry.

In-line Raman spectroscopy for characterization of an industrial poultry raw material stream

In this work, we evaluated the feasibility of Raman spectroscopy as an in-line raw material characterization tool for industrial process control of the hydrolysis of poultry rest raw material. We established calibrations (N = 59) for fat, protein, ash (proxy for bone) and hydroxyproline (proxy for collagen) in ground poultry rest raw material. Calibrations were established in the laboratory using poultry samples with high compositional variation. Samples were measured using a wide area illumination Raman probe at varying working distance (6 cm, 9 cm, 12 cm) and probe tilt angle (0°, 30°) to mimic expected in-line variations in the measurement situation. These moderate variations did not significantly affect performance for any analytes. The obtained calibrations were tested in-line with continuous measurements of the ground poultry by-product stream at a commercial hydrolysis facility over the course of two days. Measurements were acquired under demanding conditions, e.g. large variations in working distance. Reasonable estimates of compositional trends were obtained. Validation samples (N = 19) were also reasonably well predicted, with RMSEPcorr = [0.14, 1.37, 2.36, 1.51]% for hydroxyproline, protein, fat and ash, respectively. However, there were indications that further calibration development and robustification of pre-processing would be advantageous, particularly with respect to hydroxyproline and protein models. It is the authors’ impression that with such efforts, potentially in combination with development of practical measurement setup, the use of Raman spectroscopy as a process control tool for the hydrolysis of poultry rest raw materials is within reach.