Current carbon capture and utilization (CCU) technologies require high energy input and costly catalysts. Here, an effective pathway is offered that addresses climate action by atmospheric CO2 sequestration. Industrially relevant highly reactive alkali cellulose solutions are used as CO2 absorption media. The latter lead to mineralized cellulose materials (MCM) at a tailorable cellulose‐to‐mineral ratio, forming organic‐inorganic viscous systems (viscosity from 102 to 107 mPa s and storage modulus from 10 to 105 Pa). CO2 absorption and conversion into calcium carbonate and associated minerals translate to maximum absorption of 6.5 gCO2 gcellulose−1, tracking inversely with cellulose loading. Cellulose lean gels are easily converted into dry powders, shown as a functional component of ceramic glazes and cementitious composites. Meanwhile, cellulose‐rich gels are moldable and extrudable, yielding stone‐like structures tested as artificial substrates for coral reef restoration. Life Cycle Assessment (LCA) suggests new CCU opportunities for building materials, as demonstrated in underwater deployment for coral reef ecosystem restoration.
The forestry and pulp industry in Chile has been a significant contributor to the country’s gross domestic product (GDP), accounting for over 1.2% between 2018 and 2022. This sector is expected to continue growing in the coming years. The purpose of this study was to assess the environmental performance of the production of 1 tonne of short fibre bleached cellulose using the Kraft process in Chile. The assessment focused on quantifying the impact in 10 life-cycle impact categories, utilising the ReCiPe 2016 Midpoint (H) V.1.03 impact method. The evaluation followed a cradle-to-gate approach, considering the various stages including forestry activities involving biocides, fertilisers, and machinery, as well as transportation, and the subsequent industrial stage encompassing chemicals consumption, electricity usage, fuel consumption, and waste disposal. The assessment adhered to the life-cycle assessment guidelines specified in ISO 14040-44:2006 and utilised primary data from 2017, with a base year production of 1,495,000 tonnes of pulp. The results revealed that the industrial stage had the most significant environmental impact in eight out of the ten categories studied. Notably, the Global Warming Potential (GWP) reached 784 kg CO2eq/tonne of cellulose, which is noticeably higher in comparison to other countries but consistent with domestic and Ecoinvent 3.4 results. Additionally, biogenic emissions reached 3140 kg CO2biogenic/tonne of cellulose, primarily due to the combustion of waste wood and black liquor for energy recovery and electricity generation delivered to the national grid. The forestry stage was found to be the primary contributor to marine eutrophication (MAEU) and stratospheric ozone depletion (SOD), accounting for up to 86% of this environmental impact category. These results can be attributed to the usage of chemicals such as nitrogen-based fertilisers and biocides (fungi and herbicides). These findings provide quantified information that can facilitate informed comparisons with similar processes and aid in decision-making to improve the forestry-industrial sector. Emphasis should be placed on those activities that have the most significant impacts on the Chilean pulp sector, thereby promoting sustainable practices and mitigating environmental consequences.
The construction sector undeniably has an impact on sustainability in its three dimensions: economic, social, and environmental. In this context, 3D concrete printing (3DCP) has emerged over the last decade as an attractive technology for transforming this sector. It enables the manufacture of construction elements while saving time, reducing waste, and eliminating the need for molds. However, assessments of the environmental performance of implementing this technology are limited, particularly under representative production conditions. This study evaluates the footprint family indicators, carbon footprint (CF), ecological footprint (EF), and water footprint (WF), of different mixtures of 1 m3 of 3D-printed concrete, with 1m of a high printed wall. These mixtures were made with a proportion of fresh solid aggregates; brick and concrete rubble (as demolition waste (CDW) materials) were used as partial replacements for cement. In addition, the environmental impact of using two printing technologies, gantry and robotic arm systems, is analyzed. The results show that materials are the main source of environmental impacts; the replacement of some of the cement reduces CF and EF by up to 20% and 19%, respectively, while preserving printability and buildability, as demonstrated by the stable fabrication of 1 m-high printed wall elements. However, moderate increases in WF were observed, which were associated with the electricity consumption of waste processing. These results confirm the potential for valorizing CDW in 3D printing mixtures. This environmental assessment under full-scale printing conditions supports sustainability-oriented decision-making in the construction industry.
This research studies the biodegradation of sunflower-type vegetative oil in two proposed activated sludge systems, the first one to biologically treat an influent containing only vegetative oil and the second one to treat a mixture of vegetable oil plus saccharose. The purpose of these analyses is to evaluate the differential impact caused by the soluble substrate saccharose on the removal of vegetative oil. Vegetative oil biodegradation in both systems was studied and quantified via integral mass balance, and relevant operating parameters were monitored. This experimentation based on the mass balance estimation of biodegraded vegetative oil serves as a reference to understand the effect of soluble substrates present in mixed wastewater on oil biodegradation. Information was generated on the performance of the two activated sludge treatment systems. Both influents were pre-stirred before they entered the bench-scale activated sludge plants. The working range for sunflower oil concentration was 120 to 520 mg/L for the influent with sunflower oil and 180 to 750 mg/L for the influent with sunflower oil and saccharose. Biodegradation was in the order of 56 to 72% and 47 to 67%, respectively. The removal of sunflower oil in biodegradation and flotation was in the order of 90% in both scenarios.
The need to get an appropriate quantification of the sustainability indicators involves the use of site-specific information that could come from several sources, affecting its quality. This study analyses the quality and sources to build eight environmental, seven social and four economic indicators for eight electricity generation technologies in 2005, 2009 and 2015 as reference years, following the ISO 14.040-44:2006 life cycle assessment approach. The results show for the three dimensions important differences among the periods, reaching over 400% of reduction in 2015 in case of acidification for coal power plants, thanks to environmental regulations. For levelized electricity cost and corruption index, the variations reach around 40% and 30%, mainly for fossil fuel-based power plants. These changes support the need to have a centralized, reliable and accurate data system of registration, in order to contribute to the sustainability of the electricity system in Chile.
La industria de la construcción representa gran parte del consumo de recursos naturales, proyectándose el aumento de residuos de construcción y demolición (RCD) a nivel mundial en un 70% al año 2050 si no se toman medidas urgentes. La aplicación de economía circular en la construcción, requiere selección de productos en base a su potencial circular, en la fase de diseño, para optimizar la reutilización y minimizar residuos. Se propone metodología mixta combinando componentes cualitativos, explorando cómo los actores involucrados en la construcción integran, múltiples factores que influyen en la recuperación del material, asignándoles valores porcentuales que reflejan el potencial circular del producto. Esta información cuantitativa, se visualizará gráficamente en BIM (Building Information Modeling), obteniendo cuantificación sintética en porcentaje de RCD. Se compara la circularidad del modelo de estudio, con uno más favorable, y otro menos favorable. Detectándose diferencias sustanciales en la circularidad, y una determinación en porcentaje de RCD, para formular diseños informados.