# Methodology for Efficient Bitumen Storage with Reduced Energy Consumption
## 4 Conclusions  
This work has studied the possibility of adopting two different bitumen storage methods to minimize energy consumption. We compared thermally static bitumen storage at 150 \({}^{\circ}\)C to dynamic temperature storage based on fluctuations between 140 and 160 \({}^{\circ}\)C, and room temperature storage at 25 \({}^{\circ}\)C. The main findings can be summarized as follows.  
* On the physical aspect, a minor change was observed after each thermal storage method compared to the control sample. Bitumen kept its conformity to 35/50 bitumen standards at every ageing stage, and the ageing degree was the same for the three specimens after long-term ageing;
* On the chemical aspect, both the storage processes studied affected bitumen oxidative behavior differently. In the long term, ambient temperature storage minimized the sulfoxide group formation, whereas dynamic temperature storage caused an increase in the latter. This impact is acceptable and will be less if we store bitumen for a period less than the maximum storage period that we studied (90 days);
* On the energetic aspect, the calculations showed that the thermal fluctuation storage saved 6% and the ambient temperature storage saved 71% compared to the energy consumption in Bituma Company storage tanks;
* On the economic aspect, these energy savings applied to a storage period of 90 days translate into an economy of 18.8 USD/T and 1.58 USD/T when we store at room temperature and using thermal fluctuations, respectively.  
From these findings, we conclude that we can recommend both the storage methods studied in this work, with a preference for minimizing the storage period. For saving more energy, ambient temperature storage is the best choice, but it is preferable to apply it to smaller tanks to heat bitumen smoothly and rapidly when it needs to be pumped. Bitumen can be pumped immediately if its temperature is between 140 \({}^{\circ}\)C and 160 \({}^{\circ}\)C; hence, it is advisable to use dynamic temperature storage for large tanks.  
Conceptualization, A.T. and M.B.; methodology, A.T. and M.B.; validation, A.T.; formal analysis, A.T.; investigation, A.T.; data curation, A.T. and M.G.; writing--original draft preparation, A.T. and M.G.; writing--review and editing, M.B., O.A. and T.C.; visualization, A.T. and M.G.; supervision, M.B., O.A. and T.C.; project administration, M.B.; funding acquisition, M.B. All authors have read and agreed to the published version of the manuscript.  
This research was funded by IRESEN, grant number INNOPROJET-2014, \"Maintain the bitumen storage heat by using the solar thermal collector\".  
Not applicable.  
The data presented in this study are available upon request from the corresponding author.  
The authors would like to thank [PERSON] and [PERSON] for all the advice. We thank [PERSON], director at CERIT/LPEE, for allowing us to perform the ageing tests at the entity's laboratory; [PERSON], technician at CERIT/LPEE, for her tremendous help with the tests. We would like to thank [PERSON], QA engineer at MAScIR, for thermal storage services and for her patience, and [PERSON], senior researcher at MAScIR, for ATR-FTIR spectroscopy services. The authors want to thank also \"Bituma SA\" for the collaboration and the information shared to complete this study.  
The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.