Sustainable Waste Management of Date Palm Fronds in Saudi Arabia: Pyrolysis-Derived Biochar Integration into Construction Materials for Carbon Sequestration

Abstract

This study focuses on integrating biochar derived from date palm fronds into cement production in Riyadh, Saudi Arabia (KSA), to optimise carbon sequestration (CCS) and reduce carbon emissions. Employing a mixed-method approach, the research combines quantitative Life Cycle Assessment (LCA) using SimaPro software with qualitative sustainability analysis through the Bioeconomy Sustainability Indicator Model (BSIM) and Sustainable Development Goals (SDGs) indicators. Phase 1 compares the environmental impact of traditional open combustion versus pyrolysis for biochar production, revealing that pyrolysis significantly reduces carbon emissions from 3.5 tons CO₂-equivalent per ton of waste to 646 kg CO₂-equivalent. This substantial reduction supports Riyadh's climate goals and aligns with KSA’s Vision 2030 sustainability objectives. Phase 2 evaluates the integration of biochar into cement mortar, showing that a 20% substitution of cement with biochar reduces emissions by 24.81 kg CO₂-equivalent per ton of mortar, potentially saving up to 1,796 million tons of CO₂-equivalent annually based on current cement production levels. The sustainability analysis using BSIM highlights benefits such as job creation and economic growth while identifying transportation logistics risks and production efficiency risks. Additionally, the study assesses contributions to SDGs, particularly in climate action, sustainable cities, and responsible consumption and production. The study recommends optimising the supply chain, investing in advanced pyrolysis technology, and supporting market development through policy incentives. Future research should focus on the long-term performance of biochar, explore additional applications in agriculture and water treatment, and further integrate biochar into sustainable construction practices. This research provides valuable insights for advancing sustainable waste management and construction practices in Riyadh, contributing to climate action and supporting regional and global sustainability efforts.