Life Cycle Assessment Analysis Research Articles

Comparison of Embodied Carbon Footprint of a Mass Timber Building Structure with a Steel Equivalent

The main purpose of this study is to quantify and compare the embodied carbon (EC) from the materials used or designed to build the Adohi Hall, a residence building located on the University of Arkansas campus in Fayetteville, AR. It has been constructed as a mass timber structure. It is compared to the same building design with a steel frame for this study. Based on the defined goal and scope of the project, all materials used in the building structure are compared for their global warming potential (GWP) impact by applying a life cycle assessment (LCA) using a cradle-to-construction site system boundary. This comparative building LCA comprises the product stage (including raw material extraction, processing, transporting, and manufacturing) plus transportation to the construction site (nodule A1–A4, according to standard EN 15804 definitions). In this study, GWP is primarily assessed with the exclusion of other environmental factors. Tally®, as one of the most popular LCA tools for buildings, is used in this comparative LCA analysis. In this study, the substitution of mass timber for a steel structure with a corrugated steel deck and concrete topping offers a promising opportunity to understand the GWP impact of each structure. Mass timber structures exhibit superior environmental attributes considering the carbon dioxide equivalent (CO2 eq). Emissions per square meter of gross floor area for mass timber stand at 198 kg, in stark contrast to the 243 kg CO2 eq recorded for steel structures. This means the mass timber building achieved a 19% reduction in carbon emissions compared to the functional equivalent steel structure within the building modules A1 to A4 studied. When considering carbon storage, about 2757 tonnes of CO2 eq are stored in the mass timber building, presenting further benefits of carbon emission delays for the life span of the structure. The substitution benefit from this construction case was studied through the displacement factor (DF) quantification following the standard process. A 0.28 DF was obtained when using mass timber over steel in the structure. This study provides insights into making more environmentally efficient decisions in buildings and helps in the move forward to reduce greenhouse gas (GHG) emissions and address GWP mitigation.

Unveiling the potential of perovskite solar systems in building integrated installations: A consequential and prospective life cycle assessment and economic analysis

This paper addresses an integrated economic and environmental assessment where a consequential and prospective life cycle approach is applied to perovskite (PSK) building integrated photovoltaic (BIPV) systems. Two configurations are considered: slanted roof (r-BIPV) installations, and the fenestration of façades (f-BIPV). Concerning r-BIPV, PSK systems are expected to compete with crystalline silicon (c-Si) modules; whereas a glass façade is chosen as an alternative reference for f-BIPV. Assuming economic rationality as the main criteria for the adoption of technologies, a deployment time for the PSK system is estimated and the economic and environmental advantages in the Italian context are evaluated. This assessment is based on three foreground scenarios addressing the gradual development of PSK systems. The results show that while c-Si modules are preferred in the market of r-BIPV systems, PSK modules will find space in f-BIPV applications. Depending on the selected scenario, the economic benefits accumulated by Italian energy users are assessed between −0.5 % and −10.3 %. On the other hand, PSK systems imply a variation of the national GHGs emissions that ranges between + 0.01 % and −7.5 %. Depending on the scenario, the PSK-based f-BIPV systems can provide either environmental benefits (i.e., cumulative energy demand) or burdens (i.e., ecotoxicity indicators).

Environmental and Economic Life Cycle Assessment of Enzymatic Hydrolysis-Based Fish Protein and Oil Extraction

As global fish consumption rises, a large amount of waste is generated that is generally neglected. Considering the value embedded in these resources, sustainable methods become more important in extracting valuable ingredients from fish processing residues. Enzymatic hydrolysis is a fast and easily reproducible method for recovering protein ingredients and obtaining valuable by-products. To confirm its advantages, an environmental and economic impact assessment is essential. This study overviewed the sustainability and economic viability of extracting protein compounds and oil from Atlantic mackerel processing residues using enzymatic hydrolysis. Life cycle assessment (LCA) and life cycle cost analysis (LCCA) methods were employed. It was found that the climate change impact of the whole process was 0.073 kg CO2-eq per 1 g of fish protein hydrolysate (FPH). As the process produces FPH as the main product and fish oil as the by-product, economic allocation was used to distribute the impacts of FPH and fish oil. The findings of the LCCA showed that producing 1 g of FPH costs EUR 3.68. The contribution analysis indicated the crucial role of electricity and fish in environmental impacts. To ensure the accuracy of the calculation, the results of an LCA study published previously were recalculated. The sensitivity analysis showed that the results were susceptible to the region and source of electricity production. This research provides valuable insights into the sustainability and economic aspects of using enzymatic hydrolysis for extracting protein ingredients and oils from Atlantic mackerel. This can inform future investigations of environmentally friendly and economically viable solutions for extracting fish ingredients.

Cultivation of Chlorella protothecoides in the medium amended with cigarette butt leachate wastewater for enhanced biomass and macromolecular productions

Microalgal cultivation in wastewater can significantly reduce the nutrient requirements and helps in wastewater management. In this study, Chlorella protothecoides was cultured on cigarette butt leachate admixed with culture medium. The cigarette butt leachate concentrations in the culture medium were set from 0 % to 100 % and a maximum biomass production was achieved at 60 % concentration (1.24 g L−1). The lipid content of Chlorella protothecoides was increased by 9.98 %, carbohydrate content by 40.93 % and protein content by 42.93 % with 60 % of cigarette butt leachate concentration as compared to the control. Water quality analysis after microalgal cultivation revealed that the N and P elements in the cigarette butt leachate wastewater were removed completely by the microalgal growth. Life cycle assessment (LCA) analysis was carried out to evaluate the environmental sustainability of the process, which has revealed that the cigarette butt leachate wastewater has significant reduction in the environmental impacts with a CO2 emission reduction up to 338 %. The study empirically suggested that the cigarette butt leachate mixed culture medium has potentially promoted the growth, lipid and protein in Chlorella protothecoides which can improve the upstream economics along with the environmental benefits of waste management.

Economic and environmental benefit of informal waste scavenging at landfill sites: A case study at Bukit Gemuk, Tawau, Sabah, Malaysia

Recycling is an important part of the solid waste management system. However, community engagement in this activity remains relatively low. The presence of a group of individuals engaged in collecting recyclable materials at landfill sites has contributed to improving solid waste management performance. This paper aims to identify the background and activities of scavengers in collecting recyclable items at landfills, as well as the environmental impact of the scavenging activity. This study was based on questionnaires distributed to 46 scavengers in the study area. The Life Cycle Assessment (LCA) method was used to assess the environmental impact of using recyclable materials in manufacturing products. The LCA analysis could identify the contribution of recycled materials to the total savings of carbon dioxide (CO2), methane (CH4), and nitrogen dioxide (N20) by using recycled materials in the production of a new product. According to the study, the majority of those involved in the scavenging activity are immigrants from Indonesia and the Philippines. Despite safety and health concerns, their efforts to earn a living through waste scavenging are extremely valuable. Furthermore, the findings show that their contribution to the collection of recyclable materials cannot be denied. It is because the presence of this group is essential in a country where recycling awareness is low. Furthermore, the indirect contribution to the environment is important, particularly in reducing the use of natural materials in producing new materials. As a result, the government must devise a more effective strategy for recycling programs by involving all stakeholders.

Impacts of climate change on environmental and economic sustainability of flexible pavements across China

Pavements are susceptible to accelerated deterioration due to changing climate conditions, leading to increased maintenance and excess fuel consumption through pavement-vehicle interaction. China's diverse climates raise concerns about the environmental and economic sustainability of flexible pavements amid climate change and the effectiveness of preventative maintenance strategies. This study examines climate change's potential impacts on long-term pavement performance, greenhouse gas (GHG) emissions, and costs, employing the Mechanistic-Empirical Pavement Design Guide method. The calibrated World Bank's Highway Development and Management Model 4 assesses the impacts of surface characteristics on vehicle fuel consumption. Life cycle assessment and life cycle cost analysis quantify GHG emissions and costs. Results reveal significant pavement deterioration in Southeast and Central China. Preventative maintenance strategies reduce fuel consumption, with GHG emissions and cost savings from smoother driving conditions outweighing those from maintenance. These insights stress the importance of proactive maintenance strategies for mitigating climate-induced deterioration and enhancing sustainability.

A Life Cycle Assessment of Methane Slip in Biogas Upgrading Based on Permeable Membrane Technology with Variable Methane Concentration in Raw Biogas

While energy-related sectors remain significant contributors to greenhouse gas (GHG) emissions, biogas production from waste through anaerobic digestion (AD) helps to increase renewable energy production. The biogas production players focus efforts on optimising the AD process to maximise the methane content in biogas, improving known technologies for biogas production and applying newly invented ones: H2 addition technology, high-pressure anaerobic digestion technology, bioelectrochemical technology, the addition of additives, and others. Though increased methane concentration in biogas gives benefits, biogas upgrading still needs to reach a much higher methane concentration to replace natural gas. There are many biogas upgrading technologies, but almost any has methane slip. This research conducted a life cycle assessment (LCA) on membrane-based biogas upgrading technology, evaluating biomethane production from biogas with variable methane concentrations. The results showed that the increase in methane concentration in the biogas slightly increases the specific electricity consumption for biogas treatment, but heightens methane slip with off-gas in the biogas upgrading unit. However, the LCA analysis showed a positive environmental impact for treating biogas with increasing methane concentrations. This way, the LCA analysis gave a broader comprehension of the environmental impact of biogas upgrading technology on GHG emissions and offered valuable insights into the environmental implications of biomethane production.

Recycling waste plastics in asphalt mixture: Engineering performance and environmental assessment

The surging quest for asphalt pavement sustainable approaches promotes the need for balancing environmental and economic benefits. With the global production of waste plastics (WP) reaching drastic levels and recycling rates remaining disappointingly low, policymakers are increasingly advocating for the reuse of post-consumer recycled plastics in construction materials. In this study, recycling WP emerges as the most feasible solution, particularly when considering the environmental hazards associated with burning and landfilling, such as air and soil pollution. Recycling WP in asphalt mixture specifically has been quested due to the high-daily production of asphalt mixture, but concerns exist regarding its engineering performance. This study's focus is to assess the asphalt mixture mechanical response while incorporating WP, particularly High-Density Polyethylene (HP), in addition to assessing their environmental impacts. Four asphalt mixtures were rigorously evaluated containing four different asphalt binders: polymer-modified PG 76–22 and PG 70–22, unmodified PG 67–22, and HP-modified PG 67–22 asphalt binders. The investigation encompassed an in-depth analysis of asphalt binder rheological characteristics and asphalt mixtures' mechanical properties. A pivotal aspect of this study was comparing the environmental benefits of HP-modified asphalt binders against conventional polymer-modified ones. This comparison was conducted through a detailed cradle-to-gate life-cycle assessment (LCA). Results indicate that asphalt mixture containing WP material demonstrated similar engineering performance as compared to conventional mixture containing PG 70–22 asphalt binder. Further, the LCA analysis revealed that the inclusion of HP WP in asphalt binders, as compared to PG 76–22 and PG 70–22 asphalt binders, can significantly lower the global warming potential by 17.7% and 8.9%, respectively.

Multi-objective optimization of sustainable cement-zeolite improved sand based on life cycle assessment and artificial intelligence

Background Cement-zeolite improved sand can be used in diverse civil engineering applications. However, earlier research has not duly optimized its production process to attain best mechanical strength, lowest cost, and least environmental impact. This study proposes a multi-objective optimization approach using back-propagation neural network (BPNN) to predict the mechanical strength, along with an adaptive geometry estimation-based multi-objective evolutionary algorithm (AGE-MOEA) to identify the best parameters for cement-zeolite-improved sand, filling a long-lasting research gap. Methods A collection of unconfined compression tests was used to evaluate cemented sand specimens treated with stabilizers including portland cement (at dosages of 2, 4, 6, 8, and 10%) and six dosages of natural zeolite as partial replacement for cement (0, 10, 30, 50, 70, and 90%) at different curing times of 7, 28, and 90 days. The study further conducts a detailed analysis of life cycle assessment (LCA) to show how partial zeolite replacement for cement impacts the environment. Through a tuning process, the BPNN model found the optimal architecture and accurately predicted the unconfined compressive strength of cement-zeolite improved sand systems. This allowed the AGE-MOEA to optimize zeolite and cement dosages, density, curing time, and environmental impact. Results The results of this study reveal that the optimal range of zeolite was between 30-45%, which not only increased cemented sand strength, but also reduced the cost and environmental impact. It is also shown that increasing the zeolite replacement to 25-30% can increase the ultimate strength of cemented sand, yet exceeding this limit can cause the strength to decrease. Conclusions Zeolite has the potential to serve as an alternative for cement in applications that involve cemented sand, while still achieving mechanical strength performance, which is comparable or even superior. From an LCA standpoint, using zeolite as partial cement replacement in soil improvement projects is a promising alternative.

A comparative study on the combination of life cycle assessment and ecological footprints: solar photovoltaic power generation vs. coal power generation in Ningxia

In China, where energy activities, predominantly driven by fossil fuel combustion, account for nearly 90% of the country’s greenhouse gas (GHG) emissions and coal power alone contributes over 40%, the shift towards carbon neutrality is a critical national ambition. This study conducts a comprehensive comparison of the environmental impacts of solar photovoltaic power generation (SPPG) and coal power, employing both life cycle assessment and ecological footprint analysis. We meticulously analyze the complete lifecycle of SPPG, pinpointing key stages of GHG emissions, and offer nuanced, localized policy recommendations. Our findings indicate that a 1 kWp SPPG module emits 1,601.18 kg of GHGs over its lifespan, equating to 1.35 kg/kW·h per unit of electricity produced—substantially lower than the 4.81 kg/kW·h emitted by coal power, thus highlighting the latter’s heightened environmental detriment. Additionally, this study assesses the ecological footprint of both energy sources in Ningxia. SPPG emerges with an ecological surplus, showcasing a per capita footprint of 0.0342 hm2, compatible with Ningxia’s ecological capacity. In stark contrast, coal power exhibits a sustained ecological deficit over the past 5 years, with a growing per capita footprint of 0.6529 hm2, underscoring its unsustainability. This research provides a detailed comparative analysis of the environmental impacts of SPPG and coal power in Ningxia, offering valuable insights for energy policymakers and industry stakeholders. It underscores the urgent need for industrial restructuring towards more sustainable and renewable energy sources, aligning with China’s broader objectives of environmental preservation and achieving carbon neutrality.

Environmental sustainability practice of sewage sludge and low-rank coal co-pyrolysis: A comparative life cycle assessment study

This study attempts to bridge the current research gaps related to the environmental burdens of low-rank coal (LRC) and sewage sludge (SS) co-pyrolysis potentially. The life cycle assessment (LCA), energy recovery and sensitivity analysis were investigated for different proportions of LRC and SS (co-)pyrolysis. The results showed that the LRC/SS pyrolysis mitigated the environmental burden with an average improvement of 43 % across 18 impact categories compared with SS pyrolysis. The best net values of energy and carbon credits were identified in SL-4 with −3.36 kWh/kg biochar and −1.10 CO2-eq/kg biochar, respectively. This study firstly proposed an optimal LRC/SS co-feed proportion at 3 to 7, which achieves the acceptable environmental burden and satisfactory energy recovery. Moreover, sensitivity analysis demonstrated this proportion is robust and adaptable. LRC/SS co-pyrolysis is a promising and sustainable alternative for SS disposal, which could meet the imperative of carbon emission mitigation and resource recycling.

Environmental concerns on the use of the electrospinning technique for the production of polymeric micro/nanofibers

The production of micro and nanofibers through the electrospinning technique is a well assessed technology that finds application in a variety of fields. Indeed, the specific features of electrospun fibers, as well as the possibility to be modelled and functionalized, ensure their great versatility. In the last decades, the widespread use of electrospun fibers promoted studies related to the evaluation of both human health and environmental risks associated to their handling and exposure. However, to date, the environmental impact strictly related to the use of the manufacturing process has been barely considered. Therefore, the present work aims to assess the environmental impacts of the electrospinning technology used to produce micro and nanofibers. To this purpose, a model polymer was systematically electrospun, varying the main system, process and external parameters, that control the electrospinning technique. A simplified life cycle assessment analysis was finally used to evaluate how the fibrous morphology, closely linked to the choice of the technological parameters, intrinsically affected the environmental impacts.

Life cycle assessment approach of silviculture and timber harvesting of Norway spruce – a case study in the Czech Republic

Compared to other sectors, the long rotation period in forest management makes it difficult to carry out a life cycle assessment (LCA). Data collection is not possible in a short time frame but would require decades. For this reason, forestry is often forced to rely on secondary data. To address this challenge, environmental impacts of the forestry sector in the Czech Republic were investigated according to the value chain corresponding to silvicultural and harvesting processes, without any further wood use options. The methodological procedure is based on the ISO 14040 and 14,044 standards, using SimaPro, an LCA software. The study was carried out in four phases of LCA in the scope of cradle-to-gate and focused on the early stages of the product life cycle. The system boundaries were set up to include seed collection, seedling production, establishment and tending of young forest stands up to 20 years of age, thinning, harvesting, maintenance of roads and extraction trails, with the endpoint is the hauling place. Three scenarios have been defined that differ in the method of harvesting. Scenario I– chainsaw felling, horse extraction. Scenario II– chainsaw (90% of hours worked) and harvester (10% of hour-worked), tractor extraction. Scenario III– chainsaw (23% of hour-worked) and harvester (77% of hour-worked), extraction by a tractor with a winch. The results show that the maintenance of the forest road network holds a significant share of the overall environmental impact of forest management. Other significant consequences are associated with timber harvesting. These impacts vary considerably depending on the mechanical equipment used. The highest impact was recorded for the third scenario, still, it is practically the most often applied, as it is the most cost-effective. The results show the need to optimize forest management practices in the future both from an economic and environmental point of view. The work on the life cycle assessment was particularly challenging because the silviculture and harvesting of raw timber involve 20 production operations. This research was based on long-term knowledge of forest typology, forest management planning, forest economics, experience with forest technologies, and regulatory measures. Thus, the findings serve for further analysis of LCA in timber production, and future analysis for other forest ecosystem services.

Considering product life cycle characteristics and industry background in environmental impact analysis and application: a case study of a television.

Life cycle assessment (LCA) is widely used to evaluate product's life cycle environmental impact and identify the environmental weaknesses. However, it is difficult for existing LCA software to perform flexible LCA analysis based on the product life cycle characteristics and industry background. Meanwhile, under the existing LCA research model, product designers and manufacturers are usually not LCA evaluators, resulting in a certain time gap between the evaluation results and product improvement. Designers with less experience in green design often find it difficult to identify high environmental impact links in products at different life cycle stages and product levels, and updated products are challenging to meet various environmental restrictions. This paper establishes a multi-module product life cycle analysis model that combines product industry background that includes basic information, assessment information, structural information, and restriction information to achieve the multi-scenario of product LCA in different dimensions in a typical domain. The calculated mechanism of the dynamic power emission factor is built according to the service time and space dimensions. The proposed method forms an integrated environmental performance evaluation of household appliance (EPEHA) system. A software assessment and an optimization method are proposed to improve the EPEHA system. The results of this study show that these proposed methods can improve the timeliness and diversity of results analysis of product LCA in the field of household appliances in China. The universal data exchange format and simple operation interface of the EPEHA system enable people related to the product to quickly understand the environmental impact of the product in different scenarios, even if they lack green design knowledge and professional software training.

Life cycle assessment and technoeconomic analysis of biofuels produced from polyculture microalgae cultivated in greywater

This study evaluated the environmental and economic impacts of substituting synthetic media with greywater for cultivating microalgae in the biofuel production process. Life cycle assessment (LCA) and technoeconomic assessment (TEA) were employed to compare the impacts of two scenarios – one containing bold's basal (BB) media and another containing greywater as growth mediums for microalgae cultivation. Scenarios 1 and 2 mitigated 1.74 and 2.14 kg CO2 per kg of biofuel production, respectively. Substituting BB media with greywater resulted in a 16.3% reduction in energy requirements, leading to a 79.3% increase in net energy recovered. LCA findings demonstrate a reduction in all seven environmental categories. TEA reveals that, despite a 21.7% higher capital investment, scenario 2 proves more economically viable due to a 39.8% lower operating cost and additional revenue from wastewater treatment and carbon credits. The minimum selling price of biofuel dropped from Rs 73.5/kg to Rs 36.5/kg, highlighting the economic and environmental advantages of substituting BB media with greywater in microalgal biofuel production.

Life cycle cost analysis and life cycle assessment of ETFE cushion integrated transparent organic/perovskite solar cells: Comparison with PV glazing skylight

ETFE cushion integrated transparent solar cell (EC-TSC) systems have gained more attention in recent years due to their lightweight structure, reduced material consumption, and renewable energy production. In this study, innovative EC-TSC systems are applied as the skylight for the atrium of a commercial building to replace the current PV glazing skylight. The environmental and economic sustainability of EC-TSC systems is investigated by applying life cycle assessment (LCA) and life cycle cost analysis (LCCA) in a cradle-to-cradle approach. LCA provides cumulative energy and greenhouse gas emissions to quantify environmental performance. LCCA considers the contribution of life cycle costs, building owner income, and social and environmental benefits to demonstrate economic viability and evaluate financial performance. A novel distributed allocation method is proposed to illustrate the impacts of recycling benefits across all life cycles. The results are compared with those of the previous PV glazing skylight. From the results, EC-TSC systems are shown to be more cost-effective and environmentally friendly than PV glazing skylights, provided the commercial product can realize the prospective physical characteristics. This paper demonstrates the significant potential of EC-TSC systems for building retrofitting in terms of economic and environmental performance, representing an important step toward supporting the transition of BIPVs to environmental and economic sustainability.

Comparative life cycle assessment of environmental impacts and economic feasibility of tomato cultivation systems in northern plains of India

To meet the growing demand for vegetable production and promote sustainable agriculture, it is imperative to implement effective input management and adopt eco-friendly farming practices. This study aims to compare the environmental impacts of conventional and organic tomato cultivation in the northern plains of India. This study utilizes SimaPro 9.1.1 software for a comprehensive cradle-to-farm gate Life Cycle Assessment (LCA), assessing production stages, identifying key environmental factors, and incorporating ReCiPe Midpoint and Endpoint methods with one-hectare as a functional unit. Findings reveal that conventional cultivation is more affected by fertilizer application and transplanting, while organic cultivation emphasizes transplanting and irrigation. Organic cultivation contributes 904.708 kg CO2, while conventional cultivation contributes 1307.917 kg CO2 to Global Warming potential. Switching to organic cultivation leads to a significant 35.04% decrease in all impact categories. Using the endpoint method, organic cultivation achieves a notable 27.16% reduction, scoring 58.30 compared to conventional cultivation's 80.04. The LCA analysis of tomato cultivation highlights Fertilizer application as the predominant environmental concern, emphasizing the need for sustainable techniques to minimize waste and mitigate environmental impacts. This study recommends imposing restrictions on fertilizer and pesticide use and formulating effective policies to promote the adoption of sustainable practices.

Environmental and economic assessment of hydrogen-powered ferries for inland transportation

This paper investigates the environmental and economic impacts of hydrogen-powered ferries in inland passenger and car transportation using Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA). Three types of electrolysers and two types of fuel cells, focusing on their manufacturing locations, are compared with two Marine Diesel Oils (MDOs) with various sulphur percentages. In addition, this study utilises the Analytical Hierarchy Process (AHP) to weigh and rank the environmental impacts of all power options based on expert opinions. As a result of the combination of LCA and AHP analysis, the most environmentally friendly power option is found to be the Solid Oxide Electrolyser-Solid Oxide Fuel Cell system for the case study, while the worst option is the Proton Exchange Membrane Electrolyser- Proton Exchange Membrane Fuel Cell system. Moreover, MDOs are the most cost-effective power options in all carbon-tax scenarios.

A Review on Navigating Sustainable Naval Design: LCA and Innovations in Energy and Fuel Choices

The naval sector holds paramount importance for the global economy, yet it entails significant environmental impacts throughout the entire life cycle of ships. This review explores the application of life-cycle assessment (LCA) in the naval sector, a methodology for evaluating the environmental impacts associated with all the life stages of a product or service. LCA analysis in the naval context is essential for identifying and mitigating environmental impacts, thus promoting more sustainable development of the sector. This work provides a comprehensive overview of current LCA applications in the naval sector, highlighting major environmental impacts, in particular focusing on greenhouse-gas emissions and climate change. Additionally, this study integrates an analysis of greenhouse-gas emissions using a normalization approach, which has enabled the comparison of various types of fuels and ships, thereby enhancing our understanding of their environmental impacts. Moreover, the limits and challenges to applying LCA in the naval sector are discussed, offering insights for future research and developments in the field. This review aims to raise awareness among policymakers, designers, and operators in the naval sector about the importance of adopting LCA for more sustainable and responsible management of naval activities, thereby contributing to the protection of the marine and global environment.

Preparation and properties of high blending phosphogypsum-desulfurization ash-waste soil based functional prefabricated autoclaved aerated concrete slabs

There is a huge stock of industrial solid waste piles such as phosphogypsum (PG), desulfurization ash (DA), and waste soil (WS) in China, and their utilization rate is insufficient. These have potential risk for environmental safety due to pollutants contained in them. In this study, after proportioning design, raw material pretreatment, bubble regulation and multi-temperature section maintenance process, successfully prepared a high blending solid waste based functional prefabricated autoclaved aerated concrete slabs (FPAS) with excellent functional performance, and the optimal ratio of each raw material is PG: WS: DA: cement: lime = 8:50:20:10:12, and the dry mass ratio is up to 75%, the compressive strength of the slabs is up to 5.2 MPa, the standard dry density is 606 kg/m3, the dry shrinkage value is 0.36 mm/m, and the post-freezing strength is 4.0 MPa, which is in line with the basic requirements in the standard “Autoclaved aerated concrete slabs” (GB/T15762), and at the same time, its fire-resistant integrity is qualified for 240 min, and the coefficient of thermal conductivity is 0.15w(m.k), airborne sound-weighted sound insulation is 46 dB, also can show different functional characteristics. In order to investigate the environmental safety of heavy metals (HMs) in the slabs, the simulation experiment of HMs leaching from outdoor stacking of slabs was carried out. The results show that the HMs in the slabs do not pose obvious risks to the natural environment and human body, but three of the characteristic HMs, Cr, Cd and Hg, have significant leaching patterns, which can be expressed by a second-order kinetic model. Finally, the life cycle assessment and cost analysis of the high blending PG-DA-WS based FPAS and the conventional aerated slabs were carried out. The main environmental damage category of the high blending PG-DA-WS based FPAS is land ecological risk, and it has obvious environmental and economic benefits compared with the conventional aerated slabs.