基于LCA理论的厂拌热再生沥青混合料环境效益评价

Environmental Benefit Evaluation of Plant Mix Hot Recycled Asphalt Mixture Based on LCA Theory

摘要: 为了系统评价厂拌热再生沥青混合料在实际工程中的环境效益，将混合料生产施工划分为旧路面铣刨、原材料生产、混合料施工三阶段，基于生命周期分析理论计算其生产施工过程中的能耗及CO₂当量排放。研究表明：随RAP掺量的增加，厂拌热再生混合料能耗及CO₂当量排放逐渐降低；混合料生产施工过程中能耗及碳排放占比混合料拌和 > 原材料生产 > 混合料运输 > 混合料摊铺压实 > 旧路面铣刨，其中原材料生产及混合料拌和两阶段产生的能耗及碳排放占比尤为突出，约为总能耗的84.4%总碳排放的80.8%；相比于普通的热拌沥青混合料，当RAP掺量低于20%时，再生混合料的能耗及CO₂当量排放略高，当RAP掺量为30%~60%时，再生混合料能够降低能耗3.2%~10.0%，减少CO₂当量排放0.33%~3.05%，环境效益显著。

Abstract: In order to systematically evaluate the environmental benefits of the plant mix hot recycling asphalt mixture in the actual project, the mixture production and construction are divided into three stages: old pavement milling, raw material production and mixture construction. Based on the life cycle analysis theory, the energy consumption and CO₂ equivalent emissions in the production and construction process are calculated. The results show that: with the increase of rap content, the energy consumption and CO₂ equivalent emission of the plant mix hot recycling mixture decrease gradually; the proportion of energy consumption and carbon emission in the process of mixture production and construction is mixture mixing > raw material production > mixture transportation > mixture paving and compaction > old pavement milling, especially in the two stages of raw material production and mixture mixing. It is about 84.4% of the total energy consumption and 80.8% of the total carbon emission. Compared with the ordinary hot mix asphalt mixture, when the rap content is less than 20%, the energy consumption and CO₂ equivalent emission of the recycled mixture are slightly higher. When the rap content is 30% - 60%, the recycled mixture can reduce the energy consumption by 3.2% - 10.0% and CO₂ equivalent emission by 0.33% - 3.05%, which has significant environmental benefits.