Efficient Water Wash in Massive Microfluidic Array for Vegetable Oil

ABSTRACT
Visionary Fiber Technologies (VFT) has developed an innovative method to efficiently water wash vegetable oils at-scale using fiber technologies. Distillers corn oil (DCO), soybean oil (SBO), and crude palm oil (CPO) are widely used in the USA and across the globe. However, inorganic (Ca, Mg, Na, K, P, Ni, V, Si, Cu, Zn, Cl and S etc.) and organic (phosphorous) impurities, common in all types of vegetables, are removed before they are consumed. Water washing (with or without dilute acid addition) of oil is a common industrial practice, but that can often produce hard-to-break microemulsions (a function of interfacial surface tension, droplet size, and operating temperature) and leads to poor separation or significant yield loss. Microfluidic reactors provide an excellent balance between mass transfer and separation during the water washing of the vegetable oil at a relatively lower pressure drop (2-10 psi/ft) and lower energy usage. Microfluidic array reactors are filled with micron-sized fibers or ribbons made of metals or polymers in the appropriate orientation. The close contact between the two immiscible phases is achieved by the fibers providing enhanced mass transfer by means of diffusion and small perturbation, as described by Deans vortices [2]. The DCO wash reactor has been commercially deployed at multiple facilities in the USA and has been able to reduce 90% of the inorganic metals and 75% of the organic impurities in a continuous flow process. Secondly, water washing of CPO removing metals ( < 20 ppm), phosphorous ( < 10 ppm), and inorganic chlorides ( < 2 ppm) without using a centrifuge has been demonstrated. Additionally, a method to clean ( < 10 ppm impurities) crude SBO by combining dilute organic acid and water has been developed. The process for SBO reduces phosphorous and metals significantly, and therefore, bleaching clay usage can be drastically lowered.