(417e) Comparison of Conventional and Newly Proposed Solvent Deasphalting Processes: Numerical Simulation Based on Energy and Cost Analysis
Oil consumption in non-OECD countries has been increasing, while the existing reserves of conventional oil keep decreasing. To replace conventional oil, many attempts have been made to use unconventional oil such as oil sand bitumen and extra heavy oil, which are difficult to extract from a reservoir. Unconventional oil requires upgrading processes because its asphaltene compounds containing a lot of sulfur and heavy metals are much higher than those of conventional oil. Among various upgrading processes, solvent deasphalting (SDA) process has the advantage of lower operating cost than other oil conversion processes and high quality deasphalted oil (DAO) can be obtained by selectively rejecting asphaltene in the SDA process. In the SDA process, about 3â5 times more solvent than feed is used to extract DAO and the solvent recycling is the most energy consuming part. In this study, we propose a novel process that consumes less energy than the conventional SDA process. In the proposed new process, the temperature of the first separation column is adjusted to efficiently operate a heat exchanger and carbon dioxide is used as a stripping agent to separate the solvent from DAO in the last separation column. To compare energy consumption and cost of the conventional and proposed SDA process, a commercial software was used for numerical simulation. The energy consumption was calculated by a graphical method using composite and grand composite curves. After calculating minimal energy consumption, operating and capital costs were obtained with changing the type of hot and cold utilities. The proposed new SDA process can produce the same quality and quantity of DAO as the conventional SDA process, but its energy consumption and total cost are lower than those of the conventional process.