CO2 Impact Analysis for Road Embankment Construction: Comparison of Lignin and Lime Soil Stabilization Treatments

Abstract

The last decade has witnessed increased attention toward products, services, and works with reduced environmental impacts. In the field of road construction, the use of alternative materials, wastes, or by-products obtained from industries is attracting considerable interest. The Life Cycle Assessment (LCA) is a powerful project-level tool that allows the assessment of the environmental impacts of a road infrastructure, from raw materials production to end of life phase. In this study, the environmental impacts (in terms of global warming potential-GWP) of an embankment construction project are investigated by a cradle-to-gate approach. The analysis focuses on all the processes involved in the construction of an embankment section, from the base to the preparation of the pavement formation level. The results are provided for two different road types and two different stabilization methods, including the use of lignin and lime. All processes that contribute towards global warming are investigated and described in detail. The most important finding of the LCA, in terms of GWP, is that the production of materials is the phase that contributes the significant share of the total environmental impact (more than 90%) for all scenarios. The lowest production-related emissions can be recorded for the scenarios involving lignin treatment for the stabilization of the embankment body. Furthermore, the percentage increase in GWP ranges between 51% and 39% for transportation activities and 10–11% for construction activities, comparing the scenarios including lime stabilization with the scenarios involving lignin treatment.

Laboratory Testing and Analysis of Clay Soil Stabilization Using Waste Marble Powder

“…However, the durability of stabilization techniques depends on the specific materials and processes used and the application. It is essential to conduct a comprehensive life cycle assessment (LCA) to evaluate the environmental impacts from cradle to grave, e.g., extraction of raw materials, manufacturing, transportation, construction, use, and disposal [8]. LCA provides a holistic perspective on sustainability by analyzing trade-offs between improved soil properties and potential consequences such as carbon emissions or toxicity [9].…”

Influence of Biomass-Modified Asphalt Binder on Rutting Resistance

“…This level of homogeneity is unnecessary for asphalt mixtures. The rationale behind this is that the price of bioadditives is likely to decrease by up to 40% when they are produced exclusively for the purpose of asphalt mixtures [87,101]. Furthermore, the examination and comparison of the quantity of CO 2 generated during biocompound production and the manufacturing procedures of cement and lime are conducted considering the severe environmental risks associated with the release of carbon dioxide.…”

“…Previous studies have reported that average kg CO 2 -eq emissions generated from the production of lignin and other biomass additive compounds produce 0.29-0.36 kg CO 2 -eq/kg of CO 2 . In contrast, lime, cement, and asphalt binder manufacturers have been estimated to generate CO 2 emissions of up to 0.94-0.99 kg CO 2 -eq/kg [35,101]. Additionally, bioadditive recycling enables the commencement of production processes immediately following their depletion, thereby potentially reducing the need for conventional additives by as much as 20% [16,102].…”

Mechanical Properties and Microscopic Mechanism of Basic Oxygen Furnace (BOF) Slag-Treated Clay Subgrades

“…An example of an alternative option is calcium sulfoaluminate (CSA) cement, a non-traditional stabilizer that possesses environmentally beneficial characteristics while also retaining effective soil stabilization capabilities [5][6][7][8][9]. Also, byproduct stabilizers, such as rice husk ash and lignin, are considered cost-effective and environmentally friendly substitutes for traditional and non-traditional stabilizers in various civil engineering applications [10][11][12][13]. In a recent study, the life cycle assessment (LCA) tool was employed to evaluate the environmental impact of lignin and lime.…”

“…In a recent study, the life cycle assessment (LCA) tool was employed to evaluate the environmental impact of lignin and lime. This assessment revealed that lignin has a significantly lower contribution to global warming potential (GWP) than lime [11].…”