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1.
Sci Total Environ ; 944: 173640, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38825200

RESUMO

Formaldehyde, a human carcinogen, is formulated into building materials in the U.S. and worldwide. We used literature information and mass balances to obtain order-of-magnitude estimates of formaldehyde inventories in U.S. residential buildings as well as associated exposures, excess morbidity, and healthcare costs along with other economic ramifications. Use of formaldehyde in building materials dates to the 1940s and continues today unabated, despite its international classification in 2004 as a human carcinogen. Global production of formaldehyde was about 32 million metric tons (MMT) in 2006. In the U.S., 5.7 ± 0.05 to 7.4 ± 0.125 MMT of formaldehyde were produced annually from 2006 to 2022, with 65 ± 5 % of this mass (3.7 ± 0.03 to 4.8 ± 0.08 MMT) entering building materials. For a typical U.S. residential building constructed in 2022, we determined an average total mass of formaldehyde containing chemicals of 48.2 ± 10.1 kg, equivalent to 207 ± 40 g of neat formaldehyde per housing unit. When extrapolated to the entire U.S. housing stock, this equates to 29,800 ± 5760 metric tons of neat formaldehyde. If the health threshold in indoor air of 0.1 mg/m3 is never surpassed in a residential building, safe venting of embedded formaldehyde would take years. Using reported indoor air exceedances, up to 645 ± 33 excess cancer cases may occur U.S. nationwide annually generating up to US$65 M in cancer treatment costs alone, not counting ~16,000 ± 1000 disability adjusted life-years. Other documents showed health effects of formaldehyde exist, but could not be quantified reliably, including sick building syndrome outcomes such as headache, asthma, and various respiratory illnesses. Opportunities to improve indoor air exposure assessments are discussed with special emphasis on monitoring of building wastewater. Safer alternatives to formaldehyde in building products exist and are recommended for future use.


Assuntos
Poluição do Ar em Ambientes Fechados , Formaldeído , Formaldeído/análise , Humanos , Estados Unidos , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Habitação , Custos de Cuidados de Saúde , Carcinógenos/análise , Materiais de Construção , Exposição Ambiental/estatística & dados numéricos
2.
Radiat Prot Dosimetry ; 200(10): 938-944, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38855821

RESUMO

An assessment of radioactivity concentration of reinforced cement concrete types of house was conducted in the valley region of Manipur, India. The average radioactivity concentration of 226Ra, 232Th, and 40K of portland cements are 39 (range: 32-52) Bqkg-1, 36 (range: 22-62) Bqkg-1, and 1812 (1254-2424) Bqkg-1; for concrete are 36 (range: 26-45) Bqkg-1, 65 (range: 45-86) Bqkg-1, and 660 (639-681) Bqkg-1; for sand are 45 (30-61) Bqkg-1, 114 (range: 55-212) Bqkg-1, and 1859 (range: 1413-2232) Bqkg-1; and for bricks are 30 (range: 24-37) Bqkg-1, 148 (range:79-184) Bqkg-1, and 1444 (range: 1093-2103) Bqkg-1, respectively. The annual effective dose was observed with an average value of 1.9 (range: 0.9-3.3) mSvy-1. However, gamma index was observed with an average value of 1.1 (range: 0.5-2.0).


Assuntos
Materiais de Construção , Radioisótopos de Potássio , Monitoramento de Radiação , Rádio (Elemento) , Tório , Materiais de Construção/análise , Índia , Monitoramento de Radiação/métodos , Tório/análise , Rádio (Elemento)/análise , Radioisótopos de Potássio/análise , Radiação de Fundo , Humanos , Doses de Radiação
3.
J Environ Manage ; 364: 121362, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878568

RESUMO

Hazardous substances in demolition waste are often deemed a barrier to a circular economy owing to concerns about their fate in recycled materials. However, with the growing demand for recycling materials, it is essential to find circular solutions for construction materials but still protect health and the environment by managing hazardous substances. In this study, selected hazardous substance groups were analysed from demolition waste samples. Most of the concentrations did not raise any concerns when the safety of recycling materials was considered. However, the detection limits of laboratory chemical analysis can be discussed, as bromine was found in samples by an X-ray fluorescence (XRF)-analyser, but only one laboratory detected brominated flame retardants (BRFs). New technologies and practices are needed to follow the chemical content of materials used in the construction phase. Detecting hazardous substances in recyclable materials is the only way to achieve harmless material cycles.


Assuntos
Materiais de Construção , Retardadores de Chama , Substâncias Perigosas , Reciclagem , Substâncias Perigosas/análise , Retardadores de Chama/análise , Materiais de Construção/análise
4.
Environ Sci Pollut Res Int ; 31(25): 36938-36957, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38758437

RESUMO

Natural disasters and human demolition create vast amounts of construction and demolition waste (CDW), with a substantial portion being concrete waste. Managing this concrete waste is a daunting challenge for developing countries with limited resources, aiming to mitigate its harmful environmental effects. Therefore, the proposed approach involves using recycled fine aggregates (RFA) instead of fresh fine aggregates (FFA) in concrete, which aligns closely with achieving sustainable environmental objectives. Extensive laboratory tests were conducted to assess the effects of adding RFA to concrete. The influence of 0 to 100% RFA replacement and different curing times was investigated on compressive strength, tensile strength, resistance against chloride ion penetration and chemicals exposure, and quality of aggregates. So, around 30%, 35%, 20%, and 79% reductions in compression strength, tensile strength, modulus of elasticity, and workability were estimated when 100% RFA was used in recycled aggregate concrete (RAC). However, according to results analyses, the performance of RAC is reliable up to 50% of RFA in proposed conditions and mix design. In addition, major environmental impacts such as global warming potential, aquatic eutrophication, and aquatic acidification were reduced by 47%, 40%, and 18%, respectively, for concrete having 50% RFA than concrete having 100% FFA.


Assuntos
Materiais de Construção , Reciclagem , Meio Ambiente , Resistência à Tração
5.
Sci Rep ; 14(1): 11867, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789584

RESUMO

The ecological and economic benefits of mycelium composites offer a promising opportunity for supporting sustainable development in Africa. This study focuses on assessing the environmental impact of mycelium composites for building and construction (MCBs) by conducting a life cycle assessment (LCA) in the context of Africa. It is demonstrated that the potential environmental impact of MCBs is substantially influenced by the use and source of electrical power for autoclaves, incubators, and ovens, making the culturing and post-processing phases the major environmental hotspots. The impact of MCB production is also relative to the energy mix of specific countries, being higher in countries that rely on fossil fuel energy (e.g., South Africa) and lower in those that rely more on renewable sources (e.g., Democratic Republic of the Congo, DRC). Furthermore, the impact of MCB production is found to be sensitive to travel distance, suggesting that situating production facilities closer to agricultural, agro-industrial, and/or forestry waste sources could be more beneficial than interregional sourcing, for example. It is also demonstrated that MCBs have the potential to be a more ecologically sustainable alternative to some conventional construction materials (e.g., concrete) over an entire life cycle. Based on the insights obtained from this LCA, some recommendations have been proposed to address potential environmental repercussions pre-emptively and proactively: this is particularly important for nations, mainly in the Global South, that exhibit low resilience to climate change due to limited economic resources. Furthermore, with the rapid expansion of mycelium composite technology, there is a need to increase awareness about its potential environmental impact and, ultimately, to mitigate its potential contribution to pressing environmental concerns (e.g., global warming and climate change). Consequently, this study also adds to the existing body of literature on LCA studies, delineating key factors for consideration in future LCA studies and providing guidance for the sustainable establishment and expansion of this technology.


Assuntos
Materiais de Construção , Micélio , Micélio/crescimento & desenvolvimento , África , Meio Ambiente , Desenvolvimento Sustentável
6.
Environ Sci Pollut Res Int ; 31(24): 35369-35395, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38724851

RESUMO

The cement industry is among the top three polluters among all industries and the examination of the nonlinear and cointegration dynamics between cement production and CO2 emissions has not been explored. Focusing on this research gap, the study employs a novel Markov-switching autoregressive distributed lag (MS-ARDL) model and its generalization to vector error correction, the MS-VARDL model, for regime-dependent causality testing. The new method allows the determination of nonlinear long-run and short-run relations, regime duration, and cement-induced-CO2 emission cycles in the USA for a historically long dataset covering 1900-2021. Empirical findings point to nonlinearity in all series and nonlinear cointegration between cement production and cement-induced CO2 emissions. The phases of regimes coincide closely with NBER's official economic cycles for the USA. The second regime, characterized by expansions, lasts twice as long relative to the first, the contractionary regime, which contains severe economic recessions, as well as economic crises, the 1929 Great Depression, the 1973 Oil Crisis, the 2009 Great Recession, and the COVID-19 Shutdown and Wars, including WWI and II. In both regimes, the adverse effects of cement production on CO2 emissions cannot be rejected with varying degrees both in the long and the short run. Markov regime-switching vector autoregressive distributed lag (MS-VARDL) causality tests confirm unidirectional causality from cement production to CO2 emissions in both regimes. The traditional Granger causality test produces an over-acceptance of causality in a discussed set of cases. Industry-level policy recommendations include investments to help with the shift to green kiln technologies and energy efficiency. National-level policies on renewable energy and carbon capture are also vital considering the energy consumption of cement production.


Assuntos
Dióxido de Carbono , Materiais de Construção , Dióxido de Carbono/análise , Estados Unidos , Cadeias de Markov , Monitoramento Ambiental/métodos , Poluição do Ar
7.
Waste Manag Res ; 42(9): 797-805, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38584402

RESUMO

The decarbonisation of the steel and cement industry is of utmost importance in tackling climate change. Hence, steel production in modern integrated steel mills will be shifted towards electric arc furnaces in the future, in turn causing dwindling supplies of blast furnace slag, which is used as a supplementary cementitious material inter alia to reduce the CO2 emissions of cement production. Achieving a sustainable circular steel and building material economy requires the valorisation of currently landfilled steel slags and investigating utilisation options for electric arc furnace slag, which is increasingly being generated. For this purpose, different metallurgical residues and by-products were treated by carbothermal reduction in an inductively heated graphite crucible and then rapidly cooled by wet granulation, yielding a slag fraction similar to granulated blast furnace slag and a metal fraction valuable as a secondary raw material. A spreadsheet-based model was developed to calculate residue combinations to accomplish target compositions of the slag and metal fractions to fulfil previously identified requirements of the targeted cementitious and ferrous products. The results demonstrate the high accuracy of the model in predicting the properties (e.g. main oxide composition) of the generated slag and metal fraction, which fulfil the needed requirements for their use as (i) a supplementary cementitious material and (ii) a secondary raw material in steel production.


Assuntos
Materiais de Construção , Resíduos Industriais , Ferro , Metalurgia , Aço , Resíduos Industriais/análise , Ferro/química , Gerenciamento de Resíduos/métodos , Reciclagem/métodos
8.
Environ Res ; 251(Pt 2): 118735, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518905

RESUMO

Inert construction and demolition waste from Hong Kong (HK public fills) has been used for marine trial reclamation in the Guanghai Bay (GHWT) of the Chinese Mainland. However, an environmental assessment of HK public fills is necessary due to higher radioactivity in HK soils than typical global levels. Here, radiation dose rate, gamma radionuclides and gross beta of HK public fills were analyzed. The origin information was explored using natural primordial radionuclides as fingerprints. Our data show that radiation dose rate of HK public fills before disposal was 0.14-0.54 (0.33 ± 0.03) µSv/h (n = 16,722 data with 2787 ships) in 2014, which is less than the GHWT background. Monthly detection of 238U, 226Ra, 210Pb, 232Th, 228Th, 40K, and gross beta in HK public fills was conducted on three random ships. Their specific activities were <6.27-155.5, 58.7-98.7, <7.83-238.2,97.9-168.6, 87.1-136.0, 463.1-1,018, and 1047-1658 Bq/kgDW, respectively. These results suggest that the radioactivity levels of HK public fills are essentially the same as the GHWT background. The study assessed potential risks using various indices icluding Raeq (Radium equivalent activity), Hex (External radiation hazard index), Hin (Internal radiation hazard index), Iγ (Gamma index), AUI (Activity utilization index), AUI (Activity utilization index), E (Annual effective dose), AGDE (Annual gonadal dose equivalent), RLI (Representative level index), Din (Indoor air absorbed dose rate), Dout (Outdoor air absorbed dose rate), and ELCR (Excess lifetime cancer risk). The study suggests that HK public fills should be used for the trial reclamation rather than building-house materials. This provides valuable insights for the resource utilization and minimizing environmental pollution of HK public fills. The aim is to offer fundamental technical assistance for future waste resource utilization, ecological protection, and restoration in the Guangdong-Hong Kong-Macao Greater Bay Area.


Assuntos
Baías , Hong Kong , Monitoramento de Radiação/métodos , Materiais de Construção/análise
9.
Appl Radiat Isot ; 207: 111266, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461629

RESUMO

Brazil is the fourth largest cement consumer in the world and the largest producer in Latin America, around 1.3% of global production. The main inputs in the manufacture of cement are limestone and clay. Few studies have been carried out in the country on the risk of these materials used in civil construction. Therefore, the objective of this present work is to evaluate the radiological danger that they can present to society. Gamma spectrometry analysis on 16 samples of different brands of cement used as construction material in Rio de Janeiro (Brazil) was performed in this study, using an HPGe detector and the Genie 2000 data acquisition software. Samples were set to count for an accumulation time of 14,400 s (4 h) and all measurements were corrected to eliminate background and backscattering. Activity concentrations are determined for 226Ra was from (41.2 ± 1.6 to 174.9 ± 3.9) Bq kg-1, 232Th was from (15.7 ± 0.5 to 43.1 ± 0.7) Bq kg-1 and 40K was from (82.6 ± 7.2 to 254 ± 17) Bq kg-1. To assess radiological health risks: mean values of Radium Activity Equivalent 150.0 ± 3.4 Bq kg-1, Annual Gonadal Dose Equivalent 468 ± 11 µSv year-1 and Lifetime Excess Cancer Risk (ELCR) 2.42 ± 0.06 were calculated. Total Absorbed Dose Rates ranged from 72.2 ± 1.7 to 225.1 ± 5.2 nGy h-1. The damage to collective health was also estimated from the annual effective dose rates with an estimated total cost of damage to health of US$ 130 million. Values are generally within global limits reported by UNSCEAR.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Radioisótopos de Potássio/análise , Tório/análise , Monitoramento de Radiação/métodos , Brasil , Materiais de Construção/análise , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Espectrometria gama
10.
Artigo em Inglês | MEDLINE | ID: mdl-38541314

RESUMO

This article reports the results of an investigation into the activity concentration of natural radionuclides in raw building materials for underground parking lots, together with the assessment of the radiation hazard for the public related to exposure to ionizing radiations. To this purpose, high-purity germanium (HPGe) γ-ray spectrometry was employed in order to quantify the average specific activity of 226Ra, 232Th, and 40K natural radioisotopes. With the aim to assess any possible radiological health risk for the population, the absorbed γ-dose rate (D), the annual effective dose equivalent outdoor (AEDEout) and indoor (AEDEin), the activity concentration index (I), and the alpha index (Iα) were also estimated, resulting in values that were lower than the maximum recommended ones for humans. Finally, the extent of the correlations existing between the observed radioactivity and radiological parameters and of these parameters with the analyzed samples was quantified through statistical analyses, including Pearson's correlation, a principal component analysis (PCA), and a hierarchical cluster analysis (HCA). As a result, three clusters of the investigated samples were recognized based on their chemical composition and mineralogical nature. Noteworthily, this paper covers a certain gap in science since its topic does not appear in literature in this form. Thus, the authors underline the importance of this work to global knowledge in the environmental research and public health fields.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Humanos , Monitoramento de Radiação/métodos , Radioisótopos/análise , Saúde Radiológica , Espectrometria gama , Materiais de Construção/análise , Tório/análise , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise
11.
J Environ Manage ; 357: 120713, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38552520

RESUMO

With the continuous advancement of urban renewal, the application of recycled aggregates (RA) is a win-win measure to solve the treatment of construction waste and provide the required building materials. However, the existence of a large amount of old adhesive mortar (OAM) makes it difficult for RA to equivalently replace natural aggregates (NA) due to their higher water absorption and crushing index, as well as a lower apparent density. From the published literature on enhancing RA, the most mature and easiest method for construction is physical enhancement technology. Therefore, through a review of recent related researches, this article summarizes and compares the modification effects of mechanical grinding technology, traditional heating and grinding technology, and microwave heating technology on the physical properties of RA, including water absorption, apparent density, and crushing value. The related modification mechanisms were discussed. Additionally, the impacts of different physical enhancement technologies on the environment and economy effects are assessed from the perspectives of carbon emissions and cost required during processing. Based on multi-criteria analysis, microwave heating technology is more efficient and cleaner, which is the most recommended in the future.


Assuntos
Resíduos Industriais , Reciclagem , Resíduos Industriais/análise , Reciclagem/métodos , Materiais de Construção , Água , Desempenho Físico Funcional
12.
J Environ Manage ; 357: 120720, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38554451

RESUMO

Construction and demolition waste, along with discarded PET plastic bottles, have evolved into a widespread global resource. However, their current disposal in landfills poses a significant environmental pollution challenge. This research is centered on evaluating the performance of cement mortar composed by larger PET particles in conjunction with sand, construction and demolition waste, and lightweight expanded polystyrene aggregates. The primary objective of this study is to formulate a blend suitable for non-structural elements that can be easily manufactured for social housing construction. This modified blend extends upon the original certified mixture employed at CEVE for brick production, which encompasses cement and 3 mm-long PET particles. The experimental analysis revealed that blend containing 8 mm-long PET particles, in combination with fine aggregates of construction and demolition waste, attained a required mechanical strength of 2 MPa, while preserving the bulk density and hydric properties of the initial PET bricks developed at CEVE in Argentina.


Assuntos
Materiais de Construção , Reciclagem , Resíduos Industriais , Instalações de Eliminação de Resíduos , Argentina
13.
Environ Sci Pollut Res Int ; 31(18): 27329-27344, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38512577

RESUMO

Recently, the usage of a cold-bonded method in the production of artificial green geopolymer coarse aggregates (GCA) has been crucial from an economic and environmental perspective because the sintering method consumes an enormous quantity of energy and generates a significant quantity of pollutants. This research investigated the manufacture of GCA via cold-bonded pelletization using two distinct industrial byproducts (GGBFS and FA) via a new and simpler pelletization technology. Three different binders were used to produce three distinct types of GCAs as partial replacements for natural coarse aggregate (NCA) at varying replacement rates (0%, 25%, 50%, and 75%). The first group used ground-granulated blast furnace slag, while the second used GGBFS with perlite, and the third used FA with perlite. An alkaline activator was commonly used with all three groups. The physical and mechanical properties of three distinct varieties of GCA were recorded. The results indicated that the mechanical and chemical properties of three different types of GCAs were nearly identical to those of natural aggregate, with the exception of their increased water absorption. According to the findings, the recommended mixtures were suitable for usage in the construction industry. The results indicated that the ratio of all investigated attributes declined as the number of GCAs increased. In contrast, lightweight concrete can be obtained at a ratio of GCA (FA with perlite) equal to 75%, where unit weight, compressive, splitting tensile, flexural, and water absorption strengths were 1.87 gm/cm3, 20.2 MPa, 1.8 MPa, 8 MPa, and 6.0%, respectively (FA with perlite).


Assuntos
Materiais de Construção , Polímeros/química , Indústria da Construção
14.
Environ Res ; 251(Pt 1): 118457, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38382666

RESUMO

Because of their high electrocatalytic activity, sensitivity, selectivity, and long-term stability in electrochemical sensors and biosensors, numerous nanomaterials are being used as suitable electrode materials thanks to developments in nanotechnology. Electrochemical sensors and biosensors are two areas where two-dimensional layered materials (2DLMs) are finding increasing utility due to their unusual structure and physicochemical features. Nanosensors, by their unprecedented sensitivity and minute scale, can probe deeper into the structural integrity of piles, capturing intricacies that traditional tools overlook. These advanced devices detect anomalies, voids, and minute defects in the pile structure with unparalleled granularity. Their effectiveness lies in detection and their capacity to provide real-time feedback on pile health, heralding a shift from reactive to proactive maintenance methodologies. Harvesting data from these nanosensors, data was incorporated into a probabilistic model, executing the reliability index calculations through Monte Carlo simulations. Preliminary outcomes show a commendable enhancement in the predictability of vertical bearing capacity, with the coefficient of variation dwindling by up to 12%. The introduction of nanosensors facilitates instantaneous monitoring and fortifies the long-term stability of pile foundations. This study accentuates the transformative potential of nanosensors in geotechnical engineering.


Assuntos
Nanotecnologia , Reprodutibilidade dos Testes , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Método de Monte Carlo , Materiais de Construção/análise , Nanoestruturas
15.
Environ Sci Technol ; 58(5): 2434-2445, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38265760

RESUMO

Source characteristics and health risks of indoor organophosphate esters (OPEs) are limited by the lack of knowledge on emission processes. This study attempted to integrate the contents and emissions of OPEs from indoor building materials to assess human health effects. Thirteen OPEs were investigated in 80 pieces of six categories of building materials. OPEs are ubiquitous in the building materials and ∑13OPE contents varied significantly (p < 0.05) from 72.8 ng/g (seam agent) to 109,900 ng/g (wallpaper). Emission characteristics of OPEs from the building materials were examined based on a microchamber method. Depending on the sample category, the observed initial area-specific emission rates of ∑13OPEs varied from 154 ng/m2/h (carpet) to 2760 ng/m2/h (wooden floorboard). Moreover, the emission rate model was developed to predict the release levels of individual OPEs, quantify source contributions, and assess associated exposure risks. Source apportionments of indoor OPEs exhibited heterogeneities in multiple environmental media. The joint OPE contribution of wallpaper and wooden floorboard to indoor dust was up to 94.8%, while latex paint and wooden floorboard were the main OPE contributors to indoor air (54.2%) and surface (76.1%), respectively. Risk assessment showed that the carcinogenic risks of tris(2-chloroethyl) phosphate (3.35 × 10-7) were close to the acceptable level (1 × 10-6) and deserved special attention.


Assuntos
Monitoramento Ambiental , Retardadores de Chama , Humanos , Ésteres/análise , Retardadores de Chama/análise , China , Organofosfatos/análise , Poeira/análise , Materiais de Construção
16.
J Environ Manage ; 352: 119947, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38198842

RESUMO

Waste concrete powder (WCP), a byproduct of construction and demolition (C&D), currently has a low degree of recycling despite its potential for environmentally friendly applications. WCP can serve as a valuable substitute for cement, offering advantages for resource conservation and carbon sequestration. However, there are very few studies that quantitatively assess the environmental impact of incorporating WCP into the circular economy as a secondary material instead of disposing of it. The energy-intensive processing of WCP raises questions about the optimal carbonation time using available equipment. This study aims to fill this knowledge gap by employing carbon footprint and life cycle assessments (LCA) to optimize WCP recycling. Three recycling WCP scenarios are analyzed. The first scenario involved the conversion of WCP into compacts that absorb CO2 during the carbonation process. The results of the first scenario revealed that the optimal carbonation time for WCP compacts was 8 h, during which 42.7 kg CO2-e per tonne of WCP compacts was sequestered. The total global warming potential (GWP) was -4.22 kgCO2-e, indicating a carbon-negative recycling process. In the second and third scenarios, LCA was conducted to compare the use of carbonated and uncarbonated WCP as a partial replacement for cement in concrete. In these scenarios, it was found that uncarbonated WCP is a more effective solution for reducing the carbon footprint of traditional concrete mixes, achieving a significant 16% reduction of GWP when 20% of cement is replaced. Conversely, using carbonated WCP as a partial cement replacement in concrete mixtures shows limited potential for CO2 uptake. The sensitivity analysis reveals that the carbon footprint of the WCP compacts production process is strongly influenced by the electricity supplier used.


Assuntos
Dióxido de Carbono , Materiais de Construção , Animais , Pós , Reciclagem/métodos , Pegada de Carbono , Carbonatos , Estágios do Ciclo de Vida
17.
J Environ Manage ; 352: 120137, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38266527

RESUMO

Using circular bio-based building materials is considered a promising solution to reduce the environmental impacts of the construction industry. To identify the pros and cons of these materials, it is essential to investigate their sustainability performance. However, the previous sustainability assessment studies are heterogeneous regarding the assessment methods and objectives, highlighting the need for a review to identify and analyse these aspects. Moreover, there is still a lack of studies reviewing the methodological issues and implications of the assessment methods, as well as the current end-of-life scenarios and circularity options for these materials. To address these gaps, this study conducts a systematic and critical review of a sample of 97 articles. The results indicate that Life Cycle Assessment (LCA) is the most frequently applied method, yet most studies are cradle-to-gate analyses of materials. Otherwise, very few studies consider the end-of-life phase, and most of the end-of-life scenarios analysed are unsustainable and have low circularity levels. The analysis also highlights the methodological issues of the assessment methods used, with a particular focus on LCA, such as a lack of consensus on system boundaries, functional units, and databases for facilitating sustainability assessments associated with the use of circular bio-based building materials. Two primary recommendations emerge from the analysis. Firstly, for LCA studies, it is recommended to increase transparency and harmonisation in assessments to improve the comparability of results. Besides, to overcome data availability issues, it is recommended to use data from multiple sources and conduct sensitivity and uncertainty analyses. Secondly, more sustainability assessments (including the three pillars) considering the whole life cycle with more sustainable end-of-life scenarios and circularity options for these materials should be conducted.


Assuntos
Indústria da Construção , Meio Ambiente , Materiais de Construção
18.
J Visc Surg ; 161(2S): 54-62, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38272758

RESUMO

Following a reminder on the quantities of carbon emitted in the healthcare sector, and casting a spotlight on those directly related to architecture, the authors of this article will develop three large-scale themes, the objective being to render hospital construction sustainable. 1. Energy consumption and how to reduce it. 2. "Low-carbon" construction and how building designers can limit emissions by the choice of construction materials. 3. The "resilience" of some constructions, their capacity to stave off obsolescence. As a conclusion, the authors present one of the most recent projects of the Brunet Saunier & Associates architecture agency: the Saint-Ouen university hospital, Grand Paris Nord. This project is illustrative of these preoccupations and demonstrates the possibility of meeting the challenges of sustainable development by means of simple and durable architecture.


Assuntos
Arquitetura Hospitalar , Humanos , Arquitetura , Conservação de Recursos Energéticos , Materiais de Construção , Desenvolvimento Sustentável
19.
J Environ Manage ; 351: 119965, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171128

RESUMO

The textile industry in Bangladesh faces environmental and health challenges due to the disposal of solid waste from Effluent Treatment Plants (ETPs). To address this issue, a study was conducted using soil from a brick industry near Dhaka, amending it with varying amounts of dry sludge to create clay bricks. The original soil had a loam texture and medium plasticity. The research found that adding 9 wt% of sludge resulted in Grade A commercial bricks with a compressive strength of 15.33 MPa and water absorption of 13.33 wt%, meeting BDS 208 standards. However, these sludge-incorporated bricks experienced more shrinkage during the burning process due to organic content, requiring additional soil to maintain conventional dimensions. Also, to assess the health hazards of these sludge-incorporated bricks, a leaching test was performed, revealing that no toxic heavy metals (Pb, Cd, Cr, Cu, Ni, and Zn) in the leachate exceeded the limits set by the United States Environmental Protection Agency (USEPA). The study indicates that textile ETP sludge can serve as a sustainable raw material for bricks, potentially reducing the environmental burden caused by textile sludge disposal by 28.75%. This innovative approach offers a promising solution to both environmental and health concerns associated with textile waste in Bangladesh's industrial sector.


Assuntos
Metais Pesados , Esgotos , Argila , Materiais de Construção , Bangladesh , Solo , Têxteis , Medição de Risco , Metais Pesados/análise
20.
Waste Manag Res ; 42(2): 111-125, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37350242

RESUMO

The construction industry plays a vital role in the economic development of any country. Concurrently, the sector also generates enormous quantities of construction and demolition waste (CDW) that damages the ecology causing environmental pollution and deteriorating human health. Recently, various governments and other organizations realized the importance of implementing construction waste management (CWM) practices to attain sustainability in construction. The current decade can be called a pathway for achieving the 2030 agenda for sustainable development goals in which CWM plays an inevitable role. However, accurately quantifying construction waste is necessary to successfully implement any CDW management plan. A detailed literature review for the current research revealed that limited information on the magnitude of construction waste is available in India. Therefore, the current paper proposes a practically viable model to estimate the waste generation index (construction waste generated per total floor area) of high-rise residential buildings in India. The waste quantification is being done based on the project documents and expert interviews. The methodology is later validated through a high-rise building with G + 18 stories located in Kerala, India. The study indicated that a high-rise concrete framed structure generates 122.3 kg m-2 of waste during construction. It was also noted that, concrete, aggregates and blocks constitute 92% of the total waste generated in the project. The developed model can also be used as a cornerstone for establishing a construction waste database at the regional level.


Assuntos
Indústria da Construção , Gerenciamento de Resíduos , Humanos , Materiais de Construção , Indústria da Construção/métodos , Gerenciamento de Resíduos/métodos , Resíduos Industriais/análise , Índia , Reciclagem
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