title: A comparative study of soft sensor design for lipid estimation of microalgal photobioreactor system with experimental validation.
abstract: This study examines the applicability of various nonlinear estimators for online estimation of the lipid concentration in microalgae cultivation system. Lipid is a useful bio-product that has many applications including biofuels and bioactives. However, the improvement of lipid productivity using real-time monitoring and control with experimental validation is limited because measurement of lipid in microalgae is a difficult and time-consuming task. In this study, estimation of lipid concentration from other measurable sources such as biomass or glucose sensor was studied. Extended Kalman filter (EKF), unscented Kalman filter (UKF), and particle filter (PF) were compared in various cases for their applicability to photobioreactor systems. Furthermore, simulation studies to identify appropriate types of sensors for estimating lipid were also performed. Based on the case studies, the most effective case was validated with experimental data and found that UKF and PF with time-varying system noise covariance is effective for microalgal photobioreactor system.
authors.affiliation: School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744, Republic of Korea.
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Yoo
authors.affiliation: School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744, Republic of Korea.
authors.forename: Dong Hwi
authors.initials: DH
authors.lastname: Jung
authors.affiliation: School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744, Republic of Korea.
authors.forename: Jung Hun
authors.initials: JH
authors.lastname: Kim
authors.affiliation: School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744, Republic of Korea. Electronic address: jongmin@snu.ac.kr.
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Lee
mesh_terms: D000465:Algorithms; D018533:Biomass; D018929:Cell Culture Techniques / Q000295:instrumentation*; D002708:Chlorella / Q000378:metabolism; D003198:Computer Simulation; D008055:Lipids / Q000032:analysis*; D058086:Microalgae / Q000378:metabolism*; D008962:Models, Theoretical; D058433:Photobioreactors / Q000382:microbiology*; D015203:Reproducibility of Results
chemical_list: D008055:Lipids
keywords: Microalgae; Non-linear estimator; Photobioreactor; Soft-sensor; System noise