Abstract
In recent years, climate changes and fossil resources depletion prompted efforts on R&D of technologies associated with the production of biodiesel, among other biofuels. However, expensive refined vegetable oils and supply shortages of waste cooking oils are still major factors hindering biodiesel market growth to substitute petroleum diesel, due to lack of economic competitiveness and sustainability issues.
We address in this paper the production of biodiesel coupled with soybean processing to study possible synergies leading to economic and sustainability gains. Simulations in Aspen Plus® were carried employing detailed thermodynamic and kinetic models from previous works; these were obtained fromexperimental and industrial data, to describe more rigorously the various unit operations. The simulation framework under analysis includes the soybeans preparation and extraction areas, the miscella distillation and physical soybean oil refining, the production of sodium methoxide and biodiesel using the homogeneous alkaline transesterification technology. A base case with a process structure and operating conditions similar to the ones reported in the literature is adopted, and several integration opportunities in the global process are identified.
Results show that biodiesel production costs can be significantly reduced from 795 $/t to 584 $/t, by incorporating in the chemical supply chain soy meal, lecithins and soy deodorization distillate (SODD) products that have high commercial value. Moreover, the integration of these processes helps to further reduce the biodiesel production costs by 2.6 % and the amount of wastewater generated by almost 10 %.
