Using seawater-based Na2CO3 medium for scrubbing the CO2 released from Bio-CNG plant for enhanced biomass production of Pseudanabaena limnetica

Abstract

The concentration of CO2, one of the most important greenhouse gases (GHG), has reached to 409.8 ± 0.1 ppm in 2019. Although there are many carbon capture and storage (CCS) methods, they are very costly and their long term use raises concern about environmental safety. Alternatively, bio-sequestration of CO2 using microalgal cell factories has emerged as a promising way of recycling CO2 into biomass via photosynthesis. In the present study, Indigenous algal strain Pseudanabaena limnetica was cultivated in pneumatically agitated 60-L flat-panel photobioreactor system. The gas was released from Bio-CNG plant as by-product into Na2CO3-rich medium and cultivated in semicontinuous mode of operation. It was observed that when CO2 was sparged in seawater-based 0.02 M Na2CO3 solution, maximum CO2 was dissolved in the system and was used for algal cultivation. Control system produced 0.64 ± 0.035 g/L of biomass at the end of 15 days, whereas CO2 sparged Na2CO3 medium produced 0.81 ± 0.046 g/L of biomass. When CO2 from Bio-CNG station was fed, it resulted in biomass production of 1.62 ± 0.070 g/L at the end of 18 days compared to 1.46 ± 0.066 g/L of biomass produced in control system which was not fed with gas released from Bio-CNG plant as by-product. Thus, feeding CO2 directly into Na2CO3 medium and operating the system semicontinuously would be efficient for scrubbing CO2 from commercial Bio-CNG plant. This study proves that feeding CO2 gas from Bio-CNG plant into Na2CO3-rich alkaline system can be used to feed algae for enhanced biomass production.

Optimization of physico-chemical parameters for the production of phycobilin protein blue pigment, phycocyanin from the cyanobacterial strain Pseudanabaena limnetica (Lemmermann) Komarek

“…As light intensity increases, requirement of CO3 and N increases and that leads to higher biomass. The nitrate requirement of P. limnetica when cultured indoor and outdoor conditions was studied earlier (18). The NaNO3 concentration used in BG11 medium was 1.5 g/L.…”

Effect of ultra-violet light radiation on Scenedesmus vacuolatus growth kinetics, metabolic performance, and preliminary biodegradation study

“…These variations in growth patterns may be attributed to the differences in the chemical structural complexity of the compounds. Also, the variations in the specific growth rates demonstrate variations in the metabolism of the different substrates by S. vacuolatus (Danesh et al 2019 ; Rambhiya1 et al 2021 ). S. vacuolatus showed the highest growth rate and biomass concentration with glucose as the sole carbon source.…”