(150f) Life Cycle Assessment on Electrochemical-Based Separative Bioreactor for Simultaneous Production and Direct Capture of Organic Acids

Nowadays, bio-based technologies and products (so-called Industrial Biotechnology) are perceived as a key source of radical innovations for green growth.  Petroleum-based chemicals are produced using hydrocarbons in crude oil products with the aid of co-reagents, such as ammonia, and multiple process steps.  In contrast, biomass containing a great amount of proteins, amino acids and lignocellulos (such as agricultural wastes, forestry residues, grasses and woody materials) is a renewable and inexpensive feedstock for the production of fuels, chemicals, materials, and heat/power.  However, separation of organic acids from fermentation broths is one of the largest hurdles to bio-based chemical production.  The bioreactors for bio-based organic acids production typically result in only dilute concentrations of organic salts because of product inhibition and the addition of neutralizing chemical to maintain the pH inside the optimal range for bio-catalyst.  Therefore, numerous studies on organic acid purification have been conducted by different types of techniques such as ion exchange, reactive extraction, membrane separation, distillation and electro-dialysis processes. 

In Argonne National Laboratory (ANL), a separative bioreactor using resin-wafer electrodeionization (RW-EDI) has been successfully applied to separate the organic acid (e.g., gluconic acid and lactic acid) from the biocatalyst as it is produced.  However, the environmental benefits of the developed RW-EDI technology were not critically evaluated throughout the process life-cycle point of view.  Therefore, the objectives of our study were (1) to quantify the environmental impacts of different types of the biocatalytic processes for capturing the organic acids using life cycle assessment (LCA), (2) to estimate the processing cost of RW-EDI for various levels of organic acid recovery, and (3) to evaluate the engineering, environmental, and economic (3E) performance for different types of processes.  The environmental impacts and benefits of different types of biocatalytic processes were quantified by LCA using Umberto 5.6 with the ReCiPe methodology for both midpoint and endpoint assessments. The results indicated that a significant environmental benefits can be achieved by the RW-EDI process.  It was concluded that RW-EDI is an effective platform for the simultaneous production and direct capture of organic acids with great improvement in the 3E aspects.