Chitralekha Dasgupta

Development of suitable photobioreactors for CO2 sequestration addressing global warming using green algae and cyanobacteria.

CO(2) sequestration by cyanobacteria and green algae are receiving increased attention in alleviating the impact of increasing CO(2) in the atmosphere. They, in addition to CO(2) capture, can produce renewable energy carriers such as carbon free energy hydrogen, bioethanol, biodiesel and other valuable biomolecules. Biological fixation of CO(2) are greatly affected by the characteristics of the microbial strains, their tolerance to temperature and the CO(2) present in the flue gas including SO(X), NO(X). However, there are additional factors like the availability of light, pH, O(2) removal, suitable design of the photobioreactor, culture density and the proper agitation of the reactor that will affect significantly the CO(2) sequestration process. Present paper deals with the photobioreactors of different geometry available for biomass production. It also focuses on the hybrid types of reactors (integrating two reactors) which can be used for overcoming the bottlenecks of a single photobioreactor.

Cell growth kinetics of Chlorella sorokiniana and nutritional values of its biomass

The present study investigates the effects of different physico-chemical parameters for the growth of Chlorella sorokiniana and subsequently determination of nutritional values of its biomass. Most suitable temperature, light intensity, pH, and acetic acid concentration were 30°C, 100 μmol m(-2)s(-1), pH 7.5, and 34.8mM, respectively for the growth of this microorganism. Arrhenius growth activation energy, Ea was calculated as 7.08 kJ mol(-1). Monod kinetics constants: maximum specific growth rate (μ max) and substrate (acetic acid) affinity coefficient (Ks) were determined as 0.1 ± 0.01 h(-1) and 76 ± 8 mg L(-1), respectively. Stoichiometric analysis revealed the capture of 1.83 g CO2 and release of 1.9 g O2 for 1g algal biomass synthesis. Algal biomass of C. sorokiniana was found rich in protein and several important minerals such as Mg, Ca, and Fe. Astaxanthin and β-carotene were extracted and quantified using high performance liquid chromatography.

Biohydrogen Production: Fundamentals and Technology Advances

This book compiles the fundamentals of biohydrogen production technology. It offers comprehensive coverage of microbiology, biochemistry, feedstock requirements, and molecular biology of the biological hydrogen production processes. It also gives insight into scale-up problems and limitations. In addition, the book discusses mathematical modeling of the various processes involved in biohydrogen production and the software required to model the processes. The book summarizes research advances that have been made in this field and discusses bottlenecks of the various processes, which presently limit the commercialization of this technology.