Please login first
Technical and Economic Viability Analysis of Optical Fiber Sensors for Monitoring Industrial Bioreactors
* 1, 2 , 2 , 2 , 2 , 2 , 1, 2
1  School of Mechanical Engineering
2  University of Campinas


Bioreactors are employed in several industries, such as pharmaceutics, energy, biomedic and food. To ensure the proper operation of these bioreactors, Enzyme-Linked Immunosorbent Assay (ELISA) and High-Performance Liquid Chromatography (HPLC) systems are commonly used. Although ELISA and HPLC provide very precise results, they are incapable of real-time monitoring and present high operational costs. Given this context, in this work we discuss the technical and economic viability of implementing fiber optics based monitoring systems in lieu of traditional ELISA and HPLC systems. We have selected fed-batch ethanol fermentative systems for our analysis, as fermentative system are not only very prevalent in different industries, but ethanol production represents a major sector of the Brazilian economy, with an annual production in excess of 35 billion liters. A simple fiber sensing system for measuring the refractive index of the fermentation broth, capable of real-time monitoring the fermentation process, is proposed and the advantages of real-time process control are discussed. Afterwards, we present the long-term economic gains of implementing such a system. We estimate that, by using readily commercially available components, the typical Brazilian ethanol plant will see a return for their investment in a time as short as 50 days, and a 5-year Internal Rate of Return (IRR) of 742% by setting up a fiber optic monitoring system over HPLC. With the provided list of components, these numbers can be easily adjusted for industries worldwide, providing incredibly attractive economic prospects.

Keywords: optical fiber sensors; bioreactor monitoring; fed-batch fermentation; high-performance liquid chromatography; technical-economic analysis
Comments on this paper
Matheus Rodrigues
Interesting analysis
This allows verifying the feasibility of investing in the sensor.
Marco César Prado Soares
Thanks for your nice comment, Matheus.

Indeed, it is very difficult to find papers explaining exactly how you can assembly a sensing system and how much would it cost. These two topics are of special relevance for transferring knowledge from the Academy to the industries and other private sectors.

Therefore, our intention here was to provide a platform and to show in an Open Access widely available paper how to perform it, how much it would cost, and to compare it to other methodologies. With these data, anyone can decide if it is actually a good investment for his own situation, and we hope that it can also show to the third and second sectors that they can count on academics when trying to improve their processes.

Moreover, as you may have noticed, we also provided a worksheet with this paper for calculating the key economic indicators of a project. We expect that this can help even engineers or managers who are not familiar with the calculation procedures to take better and based decisions.

Best regards,