Dimethyl Ether Production from Sugarcane Vinasse: Modeling and Simulation for a Techno-economic Assessment

Abstract

Industrialization and energy demand increase are highlighted as consequences of world population growth for decades. Thereby, aiming to contribute to sustainable processes capable of mitigating the effects resulting from this process, biofuels have been intensively researched, produced and used in recent years. Among the possibilities, dimethyl ether (DME) stands out with great prospects replacing liquefied petroleum gas and diesel due to its potential as clean fuel. This work aims to conjoin the production of DME, a biofuel with great prospects for technical performance, safety, and economy, with a favorable destination for vinasse, the most worrying residue of ethanol production, due to its high polluting potential and large production volume in several countries. A rigorous and robust simulation of direct synthesis of DME from vinasse-derived syngas is performed using Aspen Hysys and its supplements, evaluating the technical and economic aspects of its production in ethanol distilleries. Results of the proposed scenario point that the process is technically feasible, reaching a purity of 99.9%, respecting the minimum required by standard norms. In addition, the designed process achieved yields of 1 kg of DME for each 1.6 kg of syngas. The simulated process presented a total capital cost of 47.1 millions of dollars, operating costs of 14.1 millions of dollars per year, and utilities cost of 11.2 millions of dollars per year. Considering energy cogeneration, an economy of 9.2% was reached, resulting in a production cost of simulated stage of 98.36 US$/tonne of DME and, considering a complete scenario, an accumulated cost of 233.48 US$/tonne of DME. It demonstrates an economic competitiveness for the DME price and ensures a considerable profit margin for the process. Consequently, the investigated DME production scenario emerges as a promising diesel substitute in a realistic scenario.