Development of a Systematic Approach to Estimating Mix-Specific Dryer Burner Fuel Consumption at Asphalt Plants

Abstract

The objective of this study was twofold. Firstly, it aimed to establish a systematic approach for estimating the specific fuel consumption of dryer burners at an asphalt plant, using the plant’s available annual energy data. Secondly, it sought to quantify the potential fuel savings and environmental advantages that could be achieved by implementing readily available technologies at the asphalt plant, aiming to move toward net zero emissions. A thermodynamics-based methodology was proposed to estimate the mix-specific burner fuel consumption at an asphalt plant by using average plant energy data, which asphalt producers typically collect for developing Environmental Product Declarations (EPDs). The methodology’s applicability was validated using field burner fuel consumption data obtained from the NCHRP 9-47A project as proof of concept. Subsequently, the proposed methodology was put into practice to assess the potential burner fuel savings resulting from the adoption of available technologies. These technologies included the use of warm-mix asphalt (WMA), improved stockpile management concerning moisture content, and the insulation of the dryer drum. Implementation of the three technologies considered in the study could lead to significant burner fuel savings, ranging from 28,500 to 64,900 BTU per short ton of asphalt mix. Such fuel savings would also result in a reduction in global warming potential (GWP). This reduction in fuel consumption translated to a decrease in GWP, ranging from 3.5 to 4.6 kg CO_2e per short ton of asphalt mix.