Usage of solar aggregate stockpiles in the production of hot mix asphalt

Application of solar aggregate stockpiles in the process of storing recycled materials

“…The T4, mixture is stored on a round surface of approximately 0.5 to 0.6 m in diameter, whereas the surface exposed to sunlight in models T1 to T3 is 0.38 × 0.38 m (Figures and ). The significant effects of the surface size on temperature in the stored materials are shown in the work of Androjić et al…”

“…The results indicate that there is a constant temperature increase of all solar stockpile models during their exposure to sunlight, while the increase of the thermal insulation thickness leads to quadratic functional dependence between the referred thickness and the mixture temperature with very high coefficient of determination values (R 2 ) ranging from 0.9836 to 0.9998. As a continuation of previous research, Androjić et al analysed the effects of the variable size of the ceiling openings of solar stockpiles on the amount of accumulated thermal energy in the mineral mix. The paper analyses situations where the temperature in the stored mineral stockpiles is observed in periods exposed to sunlight, in periods without sunlight during the night, and in other periods (such as during cloudy and/or rainy days).…”

“…If such preheated mineral mixture is used, it is possible to calculate 29 potential energy savings of 2.7 kWh, which is 4.3% of the total energy requirements in the production of 1 ton of HMA. 8 Peinado et al 28 gave a rough estimate of an energy requirement of 2.62 kWh for every additional 10°C increase in asphalt temperature. By using a preheated mineral mixture with a 14°C higher input temperature compared with the mineral mixture temperature, 30 the energy required to remove moisture content can be reduced by 2.2%.…”

“…Ang et al indicated that removing 1% moisture from mineral mix results in a roughly 20% energy savings. Previous research of Androjić et al showed that the use of solar stockpiles leads to longer maintenance of accumulated thermal energy compared with conventional storage of aggregate stocpiles. The results showed that the highest temperature difference in the mineral mixture is 14°C between solar stockpiles and uncovered stockpile at 7:00 am (potential start of the daily production of the asphalt mixture).…”

“…The results showed that the highest temperature difference in the mineral mixture is 14°C between solar stockpiles and uncovered stockpile at 7:00 am (potential start of the daily production of the asphalt mixture). If such preheated mineral mixture is used, it is possible to calculate potential energy savings of 2.7 kWh, which is 4.3% of the total energy requirements in the production of 1 ton of HMA . Peinado et al gave a rough estimate of an energy requirement of 2.62 kWh for every additional 10°C increase in asphalt temperature.…”