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In the context of the European Critical Raw Materials Act, this work attempts to demonstrate the potential of residual material flows from non-ferrous metallurgy and their possible contribution to the supply security of metals by locally available new secondary resources, assuming technically and economically viable processing. Based on the aluminium, zinc, copper and lead industries, the resulting waste streams are discussed and, in particular, the complex process consisting of physical, chemical and metallurgical steps is described. Their diversity, be it slags, dusts or even sludges, has a wide variety of morphologies and compositions due to the process of generation. In the past, many concepts for reprocessing were investigated, but the goal was usually only the recovery of one target element or to avoid landfilling by using it, for example, as a building material, whereby the metals contained are completely lost. If the target is the extraction of valuables, the required interdisciplinary process development must be based on an in-depth characterization to understand the behaviour of metals and trace elements in possible extraction steps and also to develop suitable strategies for influencing the behaviour of target elements with the aim of extraction. This starts with an in-depth comprehension of the formation process, which is the subject of this article and has a direct influence on the composition and morphology of the materials, thus forming the basis for understanding the behaviour in potential recycling processes. Furthermore, typical compositions of the residual material streams, sources and, if available, quantities are shown and, in summary, an attempt is made to evaluate the materials in a SWOT analysis and to address the challenges in developing extraction steps for processing. While mine tailings are mostly found outside of Europe, the potential of the residual materials from metallurgy is local due to the processing of the concentrates in Europe. This leads to several potential advantages in a possible reprocessing, such as no or shorter transport routes, which is linked to lower quantity of emissions, defined volume and known composition, no geopolitical risk, conservation of primary resources, and increasing Europe's sustainability through a more comprehensive use of the raw materials. This article is part of the discussion meeting issue 'Sustainable metals: science and systems'. [ABSTRACT FROM AUTHOR]

Aluminium Matrix Composites (AMCs) have garnered significant attention due to their exceptional specific strength and stiffness compared to monolithic metals. Fly ash particulates are a commonly utilized and economically viable reinforcement for AMCs. This research discusses the influence of fly ash particulates on the microstructure assessment, physical characteristics, mechanical properties, and wear resistance of a stir-cast Al7075-fly ash composite. XRD analysis showed that the fly ash was uniformly distributed throughout the aluminium matrix without producing any intermetallic compound. UTS and Hardness of Al7075-fly ash composite increased with increasing % of fly ash reinforcement, going from 140 to 173 MPa and from 66 to 75 HV, respectively, and the error analysis is also presented. Results from studies of the microstructure of the aluminium alloy show that its fly ash component is evenly distributed throughout the material. The wear rate of a casted aluminum matrix composite was measured using the pin-on-disc tribotest with no lubrication. With a fixed sliding velocity of 300 rpm and a covering distance of 2000 mitres against an EN31 steel disc, wear tests were conducted at weights of 10, 20, and 30 N. [ABSTRACT FROM AUTHOR]

The combustion of briquettes made from organic and industrial residues in small boilers requires researchers to consider the characteristics of this type of fuel and methods of its combustion. For the efficient combustion of fuel briquettes, a layered combustion method with the ability to regulate the supply of combustion air is better suited. The purpose of this research is to study the thermal technical conditions of briquetted fuel combustion. In order to carry this out, a stand was created, which made it possible to determine the combustion efficiency of this type of fuel. Two types of briquettes were studied: one with 30% sunflower husks and 70% leaves, and one with and 70% sunflower husks and 30% coke breeze. The combustion results of the briquettes show that heat loss from chemical under-burning was no more than 6.25%. To determine the temperature distribution in the fuel layer, a model of unsteady heat transfer in a fixed layer was used. A calculation of the temperature fields in the layer of burned fuel briquettes was carried out, which showed that the most favorable conditions for burning briquettes were created with a layer about 15–20 cm thick for both burned briquette options. The temperature was in the range of 450–750 °C, which on the one hand corresponds to experimental data and on the other hand provides a combustion regime that occurs with a relatively low loss to the environment. This installation and mathematical model will help future studies based on the processes of other types of organic waste combustion with a grate system. [ABSTRACT FROM AUTHOR]

In this study, the 2-step hydrothermal synthesis of pure phase analcime zeolite from the combination of glass powder waste and aluminium anodizing waste was carried out, to contribute to the reduction of disposal of these industrial residues in sanitary landfills. Population growth has intensified industrial activities worldwide, increasing the generation of waste with a high potential for environmental impact. Currently, the reuse of solid wastes has become an alternative for the development of materials with greater added value. Placket Burman statistical design was used to identify the variables of greater statistical relevance in the synthesis process, aiming at future optimization. Crystallization time and temperature were verified as the most relevant variables in the synthesis, while calcination time and calcination temperature in the alkaline fusion step were the variables with less relevance. The results revealed the formation of single-phase analcime, reaching a crystallinity of up to 75% and a specific surface area of 43.3 m2.g−1. Scanning electron microscopy analysis showed the presence of particles with trapezoidal morphology, typical of analcime zeolite. Zeta potential measurement revealed an isoelectric point in pH 2.6, an important parameter in case of application in wastewater treatment. The investigated experimental conditions also enabled the formation of other zeolites, e.g., Na-P1, cancrinite, and sodalite, demonstrating that the combination of glass powder waste and aluminium anodizing waste can be used to obtain different zeolitic phases. Consequently, products with greater added value can be obtained, contributing to sustainability in the aluminium and glass industries. [ABSTRACT FROM AUTHOR]

Biohydrometallurgy as a section of hydrometallurgy uses specific metabolic capabilities of microorganisms for metal extraction. Biomining is the application of bioleaching for metal extraction from sulfide ores. For recycling, i.e., metal extraction from waste and industrial residues, there are no biohydrometallurgical technologies yet, but promising laboratory studies on metal extraction from solids. In this review article, these are summarized, and perspectives are shown. [ABSTRACT FROM AUTHOR]

The combustion of briquettes made from organic and industrial residues in small boilers requires researchers to consider the characteristics of this type of fuel and methods of its combustion. For the efficient combustion of fuel briquettes, a layered combustion method with the ability to regulate the supply of combustion air is better suited. The purpose of this research is to study the thermal technical conditions of briquetted fuel combustion. In order to carry this out, a stand was created, which made it possible to determine the combustion efficiency of this type of fuel. Two types of briquettes were studied: one with 30% sunflower husks and 70% leaves, and one with and 70% sunflower husks and 30% coke breeze. The combustion results of the briquettes show that heat loss from chemical under-burning was no more than 6.25%. To determine the temperature distribution in the fuel layer, a model of unsteady heat transfer in a fixed layer was used. A calculation of the temperature fields in the layer of burned fuel briquettes was carried out, which showed that the most favorable conditions for burning briquettes were created with a layer about 15–20 cm thick for both burned briquette options. The temperature was in the range of 450–750 °C, which on the one hand corresponds to experimental data and on the other hand provides a combustion regime that occurs with a relatively low loss to the environment. This installation and mathematical model will help future studies based on the processes of other types of organic waste combustion with a grate system.

In Sweden, a dry cover solution is commonly used to stop sulfide oxidation and the production of acid rock drainage from unattended sulfidic mine waste. Recycling a non-hazardous industrial residue, such as green liquor dregs (GLD) generated during pulp production, in this cover solution is beneficial for both the mining industry where there is a great need for cover materials and the pulp production industry. The objectives of this field study were to install and evaluate the instrumentation of sealing layers made of GLD- and bentonite-amended till, and to evaluate the practical aspects of two different methods of installation: monitoring wells and pits. This practical field study demonstrated that it is difficult to properly seal the drill holes after installing the probes in observation wells and suggests that a better (easier and less costly) alternative for future instrument installation in a sealing layer might be to excavate a pit in the protective layer after installation of the soil cover and then drill the probes into the sealing layer from that pit. [ABSTRACT FROM AUTHOR]

This research focused on the evaluation of the Fe2O3/TiO2 composite and two industrial wastes, a kaolin (Clay-K) and a blast furnace sludge (BFS), as adsorbents and/or photocatalytic materials to enhance the removal of cyanide from aqueous solutions. Cyanide adsorption tests were conducted in the absence of light. In contrast, cyanide photodegradation tests were conducted under three types of irradiations: visible light, ultraviolet (UV) light, and natural sunlight. For the latter case, two irradiance conditions were evaluated. Cyanide adsorption from aqueous phases was similar for Clay-K and TiO2/Fe2O3 materials, which adsorbed almost twice as much cyanide compared to the BFS sample. The differences observed in cyanide removal were explained in terms of the material's surface area and chemical composition, and a complexation of cyanide ions with surface metals was suggested as the most feasible adsorption mechanism. The set of cyanide photodegradation experiments promoted, in general, higher cyanide removal from the aqueous solution compared to the adsorption processes. Under the conditions used in this study and when using Clay-K and BFS as promoters, cyanide photodegradation progressively enhanced with the following radiations: visible light < UV light ~ UV+solar ≤ Visible+solar. In the case of the TiO2/Fe2O3 composite, cyanide photodegradation increased in the following order: UV light < visible light < UV+solar ~ Visible+solar. Clearly, solar radiation had a significant effect on promoting cyanide removal. For experiments conducted with natural sunlight, the set with irradiance of 600–800 W/m2 exhibited the highest cyanide removal percentage, and the BFS had the best performance among the three tested samples over a period of 2 h. Results showed the benefit of using industrial wastes to remove cyanide from aqueous solutions and illustrates remediation of industrial effluents is potentially feasible within the framework of a circular economy. [ABSTRACT FROM AUTHOR]

Successful transition to a circular bioeconomy relies on the availability and efficient use of organic feedstocks such as agricultural and food waste. Advances in industrial biotechnology provide novel tools to valorize these feedstocks differently. Less attention, however, has been directed towards assessment of the organic side-residues arising from industrial biotechnology, such as spent microbial biomass (SMB). This study aims to reflect the current state of SMB within bioeconomy and create awareness of this growing industrial resource. Data from a range of published fermentation processes is used to estimate the amount of SMB formed per product (weight per weight, wt/wt) across different types of bioproducts, namely organic acids, alcohols, polymers, amino acids, antibiotics, protein and vitamins. Varying amounts of SMB are generated depending on the bioproducts and bioprocess, where bulk bioproducts, e.g. alcohols, generate less SMB than bioproduction of high-value low-volume specialty products, e.g. vitamins. It is estimated that more than 50 million tons of nutrient-rich SMB was generated in 2013, with SMB from bulk and specialty bioproduction accounting for roughly equal amounts. Furthermore, the composition of six industrially relevant organisms is summarized and compared, highlighting the general features of SMB as a carbon-rich substrate mainly consisting of protein. The results indicate that SMB is a growing resource with a reliable supply and predictable composition. The predictable nature of SMB could make it a favorable substrate for further innovation in industrial applications and nutrient circulation within the bioeconomy, for example, by using it as a co-substrate for valorization of other biomasses. [Display omitted] • Growing amounts of spent microbial biomass with predictable content and supply. • Bulk and specialty products have similar shares of global spent microbial biomass. • Spent microbial biomass is a nutrient rich resource. • Potential valorization routes available for cross-industrial nutrient circulation. [ABSTRACT FROM AUTHOR]

Phenolic contaminants have acquired notable attention in recent years owing to their high toxicity even at low concentrations. This study reports the potential of cost‐effective activated carbon/chitosan/zero‐valent iron nanocomposite obtained from industrial waste residues on the adsorption and degradation of phenol, 2‐chlorophenol, and 2,4‐dichlorophenol from aqueous solution. The Fenton oxidation can supplement the pre‐adsorption process by altering to less hazardous compounds. The impact of initial concentration, contact time, nanocomposite dosage, pH, oxidant dosage, and temperature were monitored. The best matches among three adsorption isotherms Langmuir, Freundlich, and Harkins‐Jura were to Freundlich isotherm and the maximum adsorption capacity of phenol, 2‐chlorophenol and 2,4‐dichlorophenol reached 50.2512, 119.0476 and 114.9425 mg/g respectively. Furthermore, the activation energy, kinetic and thermodynamic parameters of Fenton‐oxidation were perused and affirmed that Fenton reactions are spontaneous with no energy barriers. The removal efficiency of phenol, 2‐chlorophenol, and 2,4‐dichlorophenol by synthesized nanocomposite was 97.7 %, 98.9 %, and 99 %, respectively. [ABSTRACT FROM AUTHOR]

ABSTRACT The use of alternative materials such as lignocellulosic residues in the production of particleboards has increased considering that these residues are produced in large volumes and often do not have an appropriate destination. This research studied the use of residues from cellulose industries, sugarcane bagasse, and castor oil-based polyurethane resin in the production of wooden panels and evaluated the influence of using these residues on the physical and mechanical properties of the panels. The products were manufactured according to the Brazilian standard ABNT NBR 14810 and the requirements of the panels were evaluated based on national and international standards. All treatments partially met the regulatory requirements. The addition of bagasse led to an improvement in physical and mechanical properties, with treatment 2 (50% wood residue and 50% bagasse) presenting the best performance, which indicates the possibility of using panels with residues with non-structural purpose in environments to improve the thermoacoustic performance of rural buildings. The statistical analysis indicated that the percentage of bagasse was significant, improving the evaluated properties.

Purpose This article aims to evaluate the phytotoxic potential of metabolites present in the waste from sugarcane processing industry, such as vinasse, filter cake and bagasse, in order to reuse them as raw materials for the production of natural herbicides. Methods Vinasse, filter cake and bagasse were submitted to different treatments, which originated 15 different samples. They were chemically identified by negative-ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI(-)FT-ICR MS), gas chromatography-mass spectrometry (GC-MS), and liquid chromatography–mass spectrometry (LC-MS). Furthermore, they were submitted to phytotoxic assays, and to total phenolic content determination. Correlation between chemical and biological methods was performed through chemometric analysis and multiple linear regression. Results From vinasse, dichloromethane (VDiCl) and ethyl acetate (VAcOEt) samples were the most phytotoxic fractions at the concentrations of 500 mg L-1 and 250 mg L-1. VDiCl inhibited L. sativa root growth by 72.6% and 59.7%, respectively, while VAcOEt inhibited by 62.13% and 30.67%, respectively. The IC50 values established for VDiCl e VAcOEt were 168.4 mg L-1 e 262.3 mg L-1, respectively. The set of analyzes provided evidence that the synergistic action between fatty acids and phenolic compounds was of paramount importance for greater phytotoxicity of fractions. Conclusion The results indicate that the waste from the sugarcane processing industry, especially vinasse, can be reused as raw material for the production of natural herbicides, minimizing the environmental risks of incorrect disposal.

This research focused on the evaluation of the Fe2O3/TiO2 composite and two industrial wastes, a kaolin (Clay-K) and a blast furnace sludge (BFS), as adsorbents and/or photocatalytic materials to enhance the removal of cyanide from aqueous solutions. Cyanide adsorption tests were conducted in the absence of light. In contrast, cyanide photodegradation tests were conducted under three types of irradiations: visible light, ultraviolet (UV) light, and natural sunlight. For the latter case, two irradiance conditions were evaluated. Cyanide adsorption from aqueous phases was similar for Clay-K and TiO2/Fe2O3 materials, which adsorbed almost twice as much cyanide compared to the BFS sample. The differences observed in cyanide removal were explained in terms of the material’s surface area and chemical composition, and a complexation of cyanide ions with surface metals was suggested as the most feasible adsorption mechanism. The set of cyanide photodegradation experiments promoted, in general, higher cyanide removal from the aqueous solution compared to the adsorption processes. Under the conditions used in this study and when using Clay-K and BFS as promoters, cyanide photodegradation progressively enhanced with the following radiations: visible light < UV light ~ UV+solar ≤ Visible+solar. In the case of the TiO2/Fe2O3 composite, cyanide photodegradation increased in the following order: UV light < visible light < UV+solar ~ Visible+solar. Clearly, solar radiation had a significant effect on promoting cyanide removal. For experiments conducted with natural sunlight, the set with irradiance of 600–800 W/m2 exhibited the highest cyanide removal percentage, and the BFS had the best performance among the three tested samples over a period of 2 h. Results showed the benefit of using industrial wastes to remove cyanide from aqueous solutions and illustrates remediation of industrial effluents is potentially feasible within the framework of a circular economy.

The chemical and anatomical properties of Eucalyptus globulus stumps barks collected from fresh stumps (SB) and from industrial stumps bark piles (ISB) were determined. The stump bark showed similar anatomical structure to that of the stem bark, however with abundant prismatic crystals in the axial parenchyma cells. Stumps barks (ISB) presented a great amount of ashes (19.2%) that were incorporated during forest and mill processing, and lower content in extractives (4.1%), lignin (18.5%) and polysaccharides (48.5%). The non-polar (DCM) extracts were composed essentially by triterpenoids, fatty acids (C8 to C28), phytosterols (sterols and steroid ketones) and fatty alcohols (C15 to C28). The polar extracts (ethanol and water) were rich in phenolic compounds, condensed tannins and flavonoids, with higher values for the ethanol extracts and for SB. The antioxidant activity of ethanol extracts from SB was higher although only moderate (IC50 6.8). The lignin monomeric composition (H:G:S) was similar in SB (1:12:45) and in ISB (1:9:26). Sugar-derived compounds formed by Py-GC/MS included more low molecular compounds in ISB than in SB (45.5% vs.20.3%) indicative of a more degraded structure. [ABSTRACT FROM AUTHOR]

This work describes the application of the biosurfactant from Candida bombicola URM 3718 as a meal additive like cupcake. The biosurfactant was produced in a culture medium containing 5% sugar cane molasses, 5% residual soybean oil and 3% corn steep liquor. The surface and interfacial tension of the biosurfactant were 30.790 ± 0.04 mN/m and 0.730 ± 0.05 mN/m, respectively. The yield in isolated biosurfactant was 25 ± 1.02 g/L and the CMC was 0.5 g/L. The emulsions of the isolated biosurfactant with vegetable oils showed satisfactory results. The microphotographs of the emulsions showed that increasing the concentration of biosurfactant decreased the oil droplets, increasing the stability of the emulsions. The biosurfactant was incorporated into the cupcake dessert formulation, replacing 50%, 75% and 100% of the vegetable fat in the standard formulation. Thermal analysis showed that the biosurfactant is stable for cooking cupcakes (180 °C). The biosurfactant proved to be promising for application in foods low in antioxidants and did not show cytotoxic potential in the tested cell lines. Cupcakes with biosurfactant incorporated in their dough did not show significant differences in physical and physical–chemical properties after baking when compared to the standard formulation. In this way, the biosurfactant has potential for application in the food industry as an emulsifier for flour dessert.

Se seleccionaron, caracterizaron, procesaron y depositaron sobre ladrillos refractarios, dos residuos industriales provenientes de procesos de la industria petroquímica y termoeléctrica, así como un mineral de cromita. La composición química y las fases cristalográficas de cada uno de estos polvos fueron determinadas mediante Fluorescencia y Difracción de Rayos X, mientras que la morfología y tamaño de partícula fueron analizados mediante Microscopía Electrónica de Barrido. Estos polvos fueron depositados mediante proyección térmica oxiacetilénica sobre ladrillos refractarios silico-aluminosos y concretos de alta alúmina de bajo cemento, cuyas referencias comerciales de la empresa Erecos S.A.S. son ER-40 y CBC-50 respectivamente. Los parámetros utilizados para la elaboración de los recubrimientos fueron optimizados a partir de recubrimientos elaborados previamente y de los resultados de simulaciones realizadas con el software Jets&poudres. De los recubrimientos obtenidos el que presentó mayor homogeneidad en su estructura fue el elaborado con el mineral de cromita, los demás evidenciaron gran cantidad de partículas sin fundir y mayor porosidad. Sin embargo, por la composición química, su buena adherencia y las fases presentes en los recubrimientos todos son potenciales candidatos para ser usados como medio protector contra el deterioro de refractarios expuestos a altas temperaturas.

Purpose This article aims to evaluate the phytotoxic potential of metabolites present in the waste from sugarcane processing industry, such as vinasse, filter cake and bagasse, in order to reuse them as raw materials for the production of natural herbicides. Method Vinasse, filter cake and bagasse were submitted to different treatments, which originated 15 different samples. They were chemically identified by negative-ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI(-)FT-ICR MS), gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS). Furthermore, they were submitted to phytotoxic assays, and to total phenolic content determination. Correlation between chemical and biological methods was performed through chemometric analysis and multiple linear regression. Results From vinasse, dichloromethane (VDiCl) and ethyl acetate (VAcOEt) samples were the most phytotoxic fractions at the concentrations of 500 mg L-1 and 250 mg L-1. VDiCl inhibited L. sativa root growth by 72.6% and 59.7%, respectively, while VAcOEt inhibited by 62.13% and 30.67%, respectively. The IC50 values established for VDiCl e VAcOEt were 168.4 mg L-1 e 262.3 mg L-1, respectively. The set of analyzes provided evidence that the synergistic action between fatty acids and phenolic compounds was of paramount importance for greater phytotoxicity of fractions. Conclusion The results indicate that the waste from the sugarcane processing industry, especially vinasse, can be reused as raw material for the production of natural herbicides, minimizing the environmental risks of incorrect disposal. [ABSTRACT FROM AUTHOR]

This work describes the application of the biosurfactant from Candida bombicola URM 3718 as a meal additive like cupcake. The biosurfactant was produced in a culture medium containing 5% sugar cane molasses, 5% residual soybean oil and 3% corn steep liquor. The surface and interfacial tension of the biosurfactant were 30.790 ± 0.04 mN/m and 0.730 ± 0.05 mN/m, respectively. The yield in isolated biosurfactant was 25 ± 1.02 g/L and the CMC was 0.5 g/L. The emulsions of the isolated biosurfactant with vegetable oils showed satisfactory results. The microphotographs of the emulsions showed that increasing the concentration of biosurfactant decreased the oil droplets, increasing the stability of the emulsions. The biosurfactant was incorporated into the cupcake dessert formulation, replacing 50%, 75% and 100% of the vegetable fat in the standard formulation. Thermal analysis showed that the biosurfactant is stable for cooking cupcakes (180 (C). The biosurfactant proved to be promising for application in foods low in antioxidants and did not show cytotoxic potential in the tested cell lines. Cupcakes with biosurfactant incorporated in their dough did not show significant differences in physical and physical–chemical properties after baking when compared to the standard formulation. In this way, the biosurfactant has potential for application in the food industry as an emulsifier for flour dessert. [ABSTRACT FROM AUTHOR]

Fuel and lubricating oil leaks produce an oily wastewater that creates an environmental problem for industries. Dissolved air flotation (DAF) has been successfully employed for the separation of oily contaminants. Collectors constitute an auxiliary tool in the DAF process that enhances the separation efficiency by facilitating the adhesion of the contaminant particles. The use of biosurfactants as collectors is a promising technology in flotation processes, as these biomolecules are biodegradable and non-toxic. In the present study, a biosurfactant was produced from the bacteria Pseudomonas aeruginosa UCP 0992 cultivated in 0.5% corn steep liquor and 4.0% vegetable oil residue in a bioreactor at 225 rpm for 120 h, resulting in a surface tension of 26.5 mN/m and a yield of 26 g/L. The biosurfactant demonstrated stability when exposed to different temperatures, heating times, pH values and salt and was characterised as a glycolipid with a critical micelle concentration of 600 mg/L. A central composite rotatable design was used to evaluate the effect of the crude biosurfactant added to a laboratory DAF prototype on the removal efficiency of motor oil. The isolated and formulated forms of the biosurfactant were also tested in the prototype after the optimisation of the operational conditions. The results demonstrated that all forms of the biosurfactant increased the oil separation efficiency of the DAF process by 65 to 95%. In conclusion, the use of biosurfactants is a promising alternative as an auxiliary tool in flotation processes for the treatment of oily waters generated by industrial activities. [ABSTRACT FROM AUTHOR]

The industrial interest in microbial surfactants has intensified in recent years due to the characteristics of these compounds, such as biodegradability, low toxicity, and effectiveness in removing heavy metals and hydrophobic organic compounds from soil and water. This paper describes the production of a biosurfactant by the yeast Candida tropicalis grown in distilled water with 2.5% molasses, 2.5% frying oil and 4% corn steep liquor. The production of the biosurfactant reached 27 g/l in a 50-l bioreactor with a surface tension of 30 mN/m. Surface tension and engine oil emulsification assays demonstrated the stability of biosurfactant under extreme conditions of temperature and pH as well as in the presence of NaCl. Chemical structures of the biosurfactant were identified using GC–MS and NMR. The isolated biosurfactant was characterised as an anionic molecule capable of reducing the surface tension of water from 70 to 30 mN/m at 0.5% of the critical micelle concentration, with no toxic effects on plant seeds or brine shrimp. In tests involving both the crude and isolated biosurfactant for the removal of heavy metals from contaminated sand under dynamic conditions, the removal rates for Zn and Cu ranged from 30 to 80%, while the best removal rate for Pb was 15%. Tests in packed columns also confirmed the ability of biosurfactant to remove Cu and Zn at rates ranging from 45 to 65%. However, lead was not removed under static conditions. The removal kinetics demonstrated that 30 min was sufficient for the removal of metals and a single washing with the biosurfactant achieved greater removal efficiency. The use of the biosurfactant led to a significant reduction in the electrical conductivity of solutions containing heavy metals. The present findings as well as a brief economic analysis suggest the great potential of this agent for industrial remediation processes of soil and water polluted with inorganic contaminants. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of different silicate rates and sources on soil chemical properties and soil contamination with heavy metals at different depths (0-15 cm, 15-30 cm and 30-45 cm). Also sugarcane leave micronutrient contents and heavy metals. The experiment was conducted on the Vargem farm, which belongs to Guaira Sugar Mill, Guaira, São Paulo, Brazil. The adopted experimental design was randomized blocks with four replications. The treatments had a factorial design 2 x 3 + 1, with two silicates (Holcim® and Agrosilício®) and three silicate rates (400, 800 and 1600 kg ha-1). The control treatment (control) had no silicate application. The RB92-5345 variety of sugarcane was planted on May 1, 2008. Foliar samples were taken at harvest and soil samples (depths: 0-15, 15-30 and 30-45 cm) were taken after harvest. The following chemical attributes were assessed: pH, CaCl2, Al3+, Ca2+, Mg2+, micronutrients: Fe, Zn, Mn, Cu, Si, and heavy metals: Cd, Cr, Ni and Pb. The use of industrial waste in the culture of sugar cane improved soil quality, providing plants with adequate nutrients levels. To use this as an alternative nutrient source does not promote contamination of soil at deeper depths. The Agrosilício® and Holcim® silicates increased pH when rates were larger. The Agrosilício® silicate increased soil Si content in the 0-15 cm soil ayer and Mn content at the 15-30 cm soil layer. The application of silicates did not cause soil contamination and sugarcane leaves were not contaminated with heavy metals. [ABSTRACT FROM AUTHOR]

• Usage of low-quality industrial residues for cement production. • Optimized clinker as eco-friendly and cost-effective alternative to portland cement. • Savings in energy, expensive raw materials and carbon dioxide. • Reduction of necessary test syntheses by statistical experimental planning program. Calcium sulfoaluminate (CSA) belite cements are of increasing importance due to their lower energy consumption and CO 2 -emission compared to Portland cements. The aim of the study was to find an optimal raw meal composition resulting in a clinker with ye'elimite as main phase. The use of calcium carbonate and the sintering temperature should be minimized. The industrial residues residual bauxite and residual kaolinite were successfully used for an eco-friendly CSA-belite cement. The optimum raw meal composition range was found to be 38–42% limestone, 10–14% anhydrite, 20% residual kaolinite and 25–32% residual bauxite, leading to ye'elimite and larnite contents of 42–45% and 24–37%, respectively. Additionally, the sintering temperature could be reduced from the common 1250–1350 °C to 1200 °C. A statistical experimental planning program has been used as a guidance to minimize the necessary amount of experiments for finding the optimum raw meal composition. [ABSTRACT FROM AUTHOR]

The viability of ground coal bottom ash as a potential Portland cement constituent to be used in building materials is assessed. Currently, coal fly ash is used to produce Portland cements and concretes. However, coal bottom ash is mainly landfilled. Gamma spectrometry analysis, compressive strength, physical and chemical testing were performed. The ground coal bottom ash activity concentration index (I = 1.03) was compared to that of the coal fly ash (I = 1.11) provided from the same thermo-electrical power plant. Ground coal bottom ash could be used in building materials in the same way as coal fly ash as a Portland cement constituent. [ABSTRACT FROM AUTHOR]

The accomplishment of the goals set in the EU Green Deal and the Agenda 2030 for Sustainable Development requires a metallurgical industry that is even more resource-efficient, environmentally friendly and socially responsible than it is today. The European Training Network SOCRATES has taken this up by developing ground-breaking metallurgical processes for the valorisation of industrial intermediate products. This short article summarises the results obtained in the 4-year project and discusses the outcomes in light of the recently adopted EU Green Deal. [ABSTRACT FROM AUTHOR]

Abstract This paper addresses the development of a process to recovery uranium, thorium and rare earth elements from an industrial residue, with a subsequent removal of U and Th from the liquor generated. Sulfuric acid digestion followed by water leaching was found to be the best method to solubilise the metals. The acid digestion was carried out with an acid sample ratio of 700 kg t−1 and a reaction time of 2 h, without temperature control. The water leaching step was performed at room temperature (25 ± 2 °C), with 1 h of mechanical stirring and 20% of solids. Under these conditions, a metal dissolution of 94%, 81% and 97% was reached for the REE, Th and U, respectively. After the metal solubilisation, a sulfuric liquor containing 0.08 g L−1 Th, 0.35 g L−1 U, 9.1 g L−1 REE, 16 g L−1 Al, 7.8 g L−1 Fe, 0.47 g L−1 Ca, 0.75 g L−1 Zn and 0.1 g L−1 Si was formed. This liquor was used in the solvent extraction stage in order to separate Th and U from the REE, as well as from other metals. The effect of the type and extractant concentration, acidity of the liquor and type and concentration of the stripping solution were investigated. The results showed that 97% of the uranium and 94% of the thorium were extracted by a mixture of 0.05 mol L−1 of Primene JM-T and 0.1 mol L−1 of Alamine 336, in a single stage. The stripping from the loaded organic phase for the simultaneous removal of U and Th can be effectively done by using 1.7 mol L−1 NaCl solution at pH 1.2. Graphical abstract Flow sheet for the recovery of U, Th and REE from an industrial residue. Unlabelled Image Highlights • A process to recover U, Th and REE from an industrial residue was proposed. • The metals were dissolved by sulfuric acid digestion followed by a water leaching. • A mixture of primary and tertiary amines is preferential for simultaneous extraction of U and Th. • NaCl solution was used to strip U and Th simultaneously from the organic phase. [ABSTRACT FROM AUTHOR]

The use of renewable resources to develop food contact materials, such as proteins or polysaccharides, and the use of industrial residues for alternative applications are trending topics for researchers and the industry. Yeast cell wall (YCW) is a very rich waste from the yeast extract industry. Due to this, the aim of this work is to develop new biodegradable films based on residual YCW and the study of the effect of plasticization on films properties. Residual YCW was used as base matrix and different concentrations of glycerol (0, 15, 25 and 35 wt%) were tested to obtain casted films. Homogeneous and yellow-brownish films, which allow seeing through them, were obtained from the YCW. Total soluble matter demonstrated that glycerol enhanced solubility of films but glycerol was retained in the polymer matrix. TGA studies indicated that YCW films exhibited substantial degradation at temperatures above 180 °C. FTIR spectra of the casted films were representative of yeast cell wall material and SEM photographs showed that cell wall maintained their shape after film formation. As expected, Young’s modulus and tensile strength values were decreased with the increasing amount of glycerol. However, elongation at break was not increased further with higher concentration of plasticizer and the addition of 15 wt% of glycerol seemed to be enough to improve mechanical properties. The linear increment of water vapour permeability with glycerol concentration was produced by the increase in water solubility in the film. Therefore, based on solubility in water, mechanical, and barrier properties, it is possible to propose yeast cells residues as film-forming material for biodegradable film developments. [ABSTRACT FROM AUTHOR]

A chromite mineral and two industrial residues produced in the petrochemical and thermoelectric industries, were selected, characterized, processed and deposited on refractory bricks. By means of X-ray fluorescence and X-ray diffraction the chemical composition and crystallographic phases of raw materials were analyzed, morphology and particle size was determinate using Scanning Electron Microscopy. The materials were deposit by oxyacetylene thermal spray on silica-alumina refractory bricks and high alumina low cement concrete, commercial references ER-40 and CBC-50 from ERECOS S.A.S.. The parameters used for the coating deposition were optimized based on preliminary test and simulations using the Jets&powders software. The chromite mineral coating displayed greater structure homogeneity than the other two coatings; the last ones presented partially melted particles and high porosity. However, based on the chemical composition, the response to adhesion test and the crystallographic phases present in the coatings, all of them are potential candidates to be used as protective barriers against corrosive effects on refractories. [ABSTRACT FROM AUTHOR]

From a current perspective, the possibility of expanding the types of industrial waste used in construction materials is addressed, with the additional intention of contributing to the mitigation of their landfills. The existing international situation regarding appropriate construction materials made with solid waste is examined. In this article we also analyzed with a qualitative methodological approach, the properties of materials revealed by the results of previous experimental scientific investigations conducted in several countries on that subject by the author of the present work with his collaborators. To that end, the qualities and values of the properties of construction materials have been described with industrial waste from various ecologically invasive landfills. The conclusions provide criteria on physical, hygienic, environmental and socioeconomic aspects to consider extending or rejecting their use. [ABSTRACT FROM AUTHOR]

This study investigates the potential use of magnesium based phosphate cement prepared from a heavy magnesium oxide and monopotassium phosphate as a binder for the production of composite panels using bio-based industrial residues such as bagasse, hemp hurds, pine sawdust, paper mill sludge and wastepaper as raw materials. These residues were used to produce light-weight and durable materials that can compare with current Portland cement based products. The phosphate binder is fast setting, cold curing and has a low carbon footprint compared to its Portland cement counterpart. The development of phosphate bonded board products promises to reduce the energy requirements in the manufacturing process of board products, and also provides an alternative route for disposal or value addition to bio-based residues by developing environmentally friendly products. The board manufacturing process was laid out on a central composite design (CCD) to model the response variable, utilizing as much residues as technically feasible. The design allowed for the production of low and medium density boards that can be used for non-structural interior finishes and partition boards. Response surface methodology (RSM) was used to show the relationships between the production variables and predict the board property by variable optimisation. Tests of mechanical and physical properties were conducted on the boards. The density of hemp boards ranged from 0.59–0.83 g/cm 3 , bagasse boards ranged from 0.54–0.78 g/cm 3 , pine boards ranged from 0.58–0.84 g/cm 3 , paper sludge boards ranged from 0.68–0.81 g/cm 3 and wastepaper boards ranged from 0.67–0.81 g/cm 3 . The study has shown that it is feasible to produce phosphate based board products using bio based industrial and agricultural residues. The physical properties of the products met the minimum requirements for cement bonded particleboard (EN 634:2007) and LD-1 grade particle board (ANSI 208.1:1999). [ABSTRACT FROM AUTHOR]

Plant growth promoting substances are widely used in modern agriculture. Several products in the market are humic substances isolated from different sources. The filter cake, a residue of sugar production, is a rich and renewable source of organic matter and these characteristics place the filter cake as a possible source of plant growth promoting substances. Humic acids (HA) from filter cake were characterized, and their effects as root growth promoters were evaluated. Chemical features of the HA were evaluated through elemental composition, acidic functional groups, E4/E6 ratio and infrared spectroscopy analyzes. The biological activity of the HA was assessed using root architecture parameters and the P-type H+-ATPase activity. The lateral root development was directly related to the stimulation of plasma membrane ATPase activity. The ability of HA to promote root development indicate that HA from filter cake can be used as environmental plant growth stimulators.Substâncias promotoras do crescimento vegetal são amplamente utilizadas na agricultura moderna. Existem vários produtos no mercado, muitos dos quais são substâncias húmicas isoladas de diferentes fontes. A torta de filtro, um resíduo da produção do açúcar, é uma fonte rica e renovável de matéria orgânica e essas características a tornam uma possível fonte de substâncias promotoras do crescimento vegetal. Ácidos húmicos (AH) da torta de filtro foram caracterizados, e foi avaliado seu efeito como promotor de crescimento radicular. As características químicas dos AH foram avaliadas por meio da composição elementar, grupos funcionais ácidos, relação E4/E6 e espectroscopia de infravermelho. A atividade biológica dos AH foi acessada avaliando-se a arquitetura radicular e a atividade da H+-ATPase de membrana plasmática. O desenvolvimento de raízes laterais foi diretamente relacionado ao estímulo da atividade da H+-ATPase. A habilidade dos AH em promover o desenvolvimento radicular indica que AH extraídos da torta de filtro podem ser utilizados como estimuladores do crescimento de plantas.

O lambari, Astyanax altiparanae, é uma espécie muito comum em rios nacionais, com grande potencial para a piscicultura nacional. Ele apresenta crescimento rápido e carne de excelente sabor, sendo muito apreciado com petisco e como isca viva para a pesca esportiva. A farinha de vísceras de aves é uma importante fonte protéica de origem animal. O trabalho foi realizado com o objetivo de avaliar a inclusão de farinha de vísceras de aves (FV) em rações para alevinos de lambari. Foram utilizados 125 alevinos, apresentando peso e comprimento inicial médio de 0,080±0,002g e 1,86±0,20cm, respectivamente, distribuídos em 25 aquários. As rações foram formuladas de forma a conter 0, 5, 10, 15 e 20% de FV na dieta. O arraçoamento foi realizado quatro vezes ao dia, na forma farelada e à vontade. O valores médios de peso final (1,47, 1,92, 2,02, 2,11 e 2,15g) e comprimento final (4,40, 4,78, 4,92, 4,92 e 5,08cm) dos alevinos de lambari apresentaram aumento linear (PThe lambari Astyanax altiparanae, is a very common species in the national rivers, with great potential for the national psyculture. It presents a fast growth and meat of eccellent flavor, being very appreciate like a delicacy and like an alive bait to sportive fishing. The poultry by-product meal is an important proteinic source from animal origin. The research was carried out with the objective to evaluate the poultry by-product meal inclusion (FV) in rations for lambari fingerlings. 125 fingerlings presenting average weight and initial length of 0.080±0.002g and 1.86±0.20cm respectively were used, they were distributed in 25 aquariums. The rations were formulated in form to contain 0, 5, 10 15 and 20% of FV in the diet. The ration giving was carried through four times a day, in a braning form and at the will. The avarage values of final weight (1.47, 19.2, 2.02, 2.11 and 2.15) and final length of (4.40, 4.78, 4.92 and 5.08cm) of the lambari fingerlings had presented linear increase (P

The forest products industry generates several residues in addition to actual products and many of these residues such as fly ash generated by bioenergy production and sludge from the waste water purification processes can be used after being properly treated. This study focused on a hypothetical case in which fly ash from bioenergy production and sludge from forest products industry waste water treatment would be granulated and produced into a forest fertilizer. The Waste Policy of the European Union and growing focus on circular economy goals both support more efficient use of industrial waste and side products and is a major driver for companies towards better material efficiency. This study assessed the global warming potential (GWP) of a potential symbiosis product based on a hypothetical granulating process including two industrial residue streams and briefly examined the drivers of the EU and Finnish policy and legal frameworks for recycling of industrial residues and for their usage as secondary raw materials for potential symbiosis products. The results indicated that the production of 1000 kg of potential symbiosis granules in our model case produced GWP burdens of 11.75 (kg CO 2 -equiv.). As an example, the production of the already existing NPK-fertilizers produced a GWP burden of 1304.92 (kg CO 2 -equiv.). Our system boundary was the actual manufacturing process. We also compared different fertilizers based on their fertilizer effect including determination of the composition of the elements in relation to the commercial fertilizer composition. The results indicate that even if the amount of the granulated ash fertilizer was bigger, the amount of environmental burden it produced was much lower. Therefore, the production of the potential symbiosis product could have benefits in terms of GWP results and overall environmental performance when compared to use of primary raw materials. [ABSTRACT FROM AUTHOR]

This study assesses the policy/legal status of both multistream residues and potential secondary products ('symbiosis products') and whether there could be environmental benefits associated with the utilization of residues from integrated pulp and paper and carbon steel mills as raw materials for such secondary products. Waste-related European Union (EU) and Finnish policy and legal instruments were reviewed to identify potential constraints for, and suggested next steps in, the development of potential process industry residue-based symbiosis products. The products were soil amendment pellets, low-grade concrete, and mine filler. A global warming potential (GWP) assessment and an exergy analysis were applied to these potential symbiosis products. Some indicative GWP calculations of greenhouse gas emissions associating similar and/or analogous products based on virgin primary raw materials, more energy-intensive processes, and the alternative treatment of these residues as wastes are also presented. This study addresses GWP, exergy, and legal aspects in a holistic manner to determine the potential environmental benefits of secondary products within the EU legal framework. The GWP assessment and exergy analysis indicate that the utilization of multistream residues causes very low environmental burdens in terms of GWP. The utilization option can have potential environmental benefits in terms of GWP through process replacement and avoided landfilling and waste treatment impacts, as well as potentially through emission reductions from product replacement if suitable and safe applications can be identified. Waste regulation does not define the legal requirements under which utilizing residues in such novel concepts as introduced in this study would be possible, nor how waste status could be removed and product-based legislation be applied to the potential products instead. [ABSTRACT FROM AUTHOR]

The concentration of carbon dioxide (CO) in the atmosphere has increased from 280 to 400 ppm in the last 10 years, and the coal-fired power plants are responsible for approximately 22 % of these emissions. The burning of fossil fuel also produces a great amount of solid waste that causes serious industrial and environmental problems. The biological processes become interesting alternative in combating pollution and developing new products. The objective of this study was to evaluate the CO biofixation potential of microalgae that were grown using gaseous effluents and solid residues of thermoelectric origin. The microalgae Chlorella fusca LEB 111 presented higher rate of CO biofixation (42.8 %) ( p < 0.01) than did Spirulina sp. LEB 18. The values for the CO biofixation rates and the kinetic parameters of Spirulina and Chlorella cells grown using combustion gas did not differ significantly from those of cells grown using CO and a carbon source in the culture media. These microalgae could be grown using ash derived from coal combustion, using the minerals present in this residue as the source of the essential metals required for their growth and the CO derived from the combustion gas as their carbon source. [ABSTRACT FROM AUTHOR]

RESUMO: A reduzida ingestão de fibra alimentar (FA) vem sendo associada ao aumento de inúmeras doenças crônico não transmissíveis. Nos últimos anos, muitos pesquisadores de países ibero-americanos vêm caracterizando adequadamente a FA em alimentos e em resíduos industriais, buscando tecnologia para produzir concentrados, desenvolvendo e testando produtos enriquecidos, a partir de alimentos regionais. O presente estudo visou, através da compilação de informações sobre FA, avaliar o potencial deste nutriente na região. Há uma grande disponibilidade de alimentos regionais e tradicionais com teor significativo de fibra alimentar como frutas, hortaliças e, principalmente, cereais e leguminosas. Fontes concentradas de FA, obtidas a partir de diferentes resíduos industriais, foram caracterizadas e avaliadas, podendo ser utilizadas no enriquecimento de alimentos. Alguns produtos enriquecidos vêm sendo testados, como biscoitos com torta de milho na Colômbia (produto contendo 16,8% de FA na base integral) e macarrão com fibra de tremoço no Chile (11,2%). No mercado cubano já se encontram produtos como pão de trigo integral (12%); produtos para fins especiais, como comprimidos de fibra de cítricos (55%) e alimentos para dieta enteral (1-1,9%). Os dados sobre conteúdo de FA apresentados neste trabalho representam alguns exemplos sobre o potencial deste nutriente nos países ibero-americanos, potencial este, que se mostrou bastante significativo. Cabe salientar, que a completa base de dados está disponível no web site do Projeto CYTED XI.6/CNPq (http://www.fcf.usp.br/cytedxi6) a qual apresenta o conteúdo de FA em 817 alimentos regionais, tradicionais e não convencionais, que podem ser conhecidos e utilizados por profissionais de diversas áreas.SUMMARY: The reduced intake of dietary fiber (DF) has been associated with the increase in the incidence of several non-transmissible chronic diseases. Recently many researchers from Iberian-American countries have been studying DF of food and industrial residues in order to improve technological knowledge about concentrates production as well as the development and test of enriched products originated from regional food. The present study aimed to evaluate the regional DF potential based on compilation of data about this nutrient. There is great availability of regional and traditional food with considerable DF amounts as we may find in fruits, vegetables and cereals and legumes. Concentrated sources of DF obtained from different industrial residues were characterized and evaluated making possible their utilization in food enrichment. Cookies added to corn residues (16,8% DF in integral weight) in Colombia, and pasta added to lupine fiber in Chile (11,2%) are examples of tested enriched products. Products like bread with whole wheat (12%), products for especial uses as well as pills of citric DF (55%) and food for enteral diets (1-1,9%) are already available on Cuba market. The dietary fiber contents presented in this work allow us to have an idea of the potential of such nutrient in Iberian-American countries. Such potential has been proved to be considerably representative. It is worth to inform that the complete DF database is available on the CYTED XI.6/CNPq Project Web site (http://www.fcf.usp.br/cytedxi6). It provides data on 817 regional, traditional and not conventional foods, that can be searched and utilized by professional from different areas.

This paper presents and discusses the application of accelerated carbonation of industrial residues in three different contexts (a landfill site, a steel manufacturing plant and a Brownfield site) aimed at storing CO 2 and obtaining additional specific environmental objectives, i.e.: the improvement of the leaching behavior of the treated residues, biogas upgrading, the production of aggregates to use in construction applications and in situ remediation of Brownfield sites. [ABSTRACT FROM AUTHOR]

This work explored several synthesis routes to obtain calcium silicates from different calcium-rich and silica-rich industrial residues. Larnite, wollastonite and calcium silicate chloride were successfully synthesised with moderate heat treatments below standard temperatures. These procedures help to not only conserve natural resources, but also to reduce the energy requirements and CO2 emissions. In addition, these silicates have been successfully tested as carbon dioxide sequesters, to enhance the viability of CO2 mineral sequestration technologies using calcium-rich industrial by-products as sequestration agents. Two different carbon sequestration experiments were performed under ambient conditions. Static experiments revealed carbonation efficiencies close to 100% and real-time resolved experiments characterised the dynamic behaviour and ability of these samples to reduce the CO2 concentration within a mixture of gases. The CO2 concentration was reduced up to 70%, with a carbon fixation dynamic ratio of 3.2 mg CO2 per g of sequestration agent and minute. Our results confirm the suitability of the proposed synthesis routes to synthesise different calcium silicates recycling industrial residues, being therefore energetically more efficient and environmentally friendly procedures for the cement industry. [ABSTRACT FROM PUBLISHER]