Techno-economic assessment of CO2 bio-fixation using microalgae in connection with three different state-of-the-art power plants

Abstract

Rezvani, S., Moheimani, N.R. and Bahri, P.A. (2016) Techno-economic assessment of CO2 bio-fixation using microalgae in connection with three different state-of-the-art power plants. Computers & Chemical Engineering, http://researchrepository.murdoch.edu.a/28750/ This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractLarge-scale microalgae cultivations for CO 2 bio-sequestration from power plants can be an alternative process to conventional technologies if the capital investments associated with carbon capture, transport and storage can be reduced or avoided. In order to counterbalance the costs required to operate massive microalgae cultivations, it is necessary to create additional revenues through biomass sales. This manuscript examines the techno-economics of microalgae cultivations for the integration with three power plant technologies using an Artificial Neural Network model. The economics are estimated using the net present value approach. The assessment is carried out at photosynthesis efficiencies ranging from 2% to 6%. The sensitivity assessment shows microalgae selling prices in the range of $440/t to $1028/t at a photosynthetic efficiency of 4% for low and high cost scenarios in order to achieve an electricity price similar to that from a conventional power plant without a CO 2 capture and storage.

Techno-Economic Study of CO2 Capture of a Thermoelectric Plant Using Microalgae (Chlorella vulgaris) for Production of Feedstock for Bioenergy

“…The selection of technology for drying depends on both the scale of production and the purpose for which dry biomass is destined [74]. As an alternative for the reduction in energy consumption in the drying of microalgal biomass, the residual heat of the power plant from which CO 2 is obtained should be used [75]. On the other hand, some methods of obtaining energy or products from microalgae are carried out with wet biomass, which would avoid energy consumption by drying the biomass.…”

The cost benefit of algal technology for combined CO2 mitigation and nutrient abatement

“…Whilst a range of extraction technologies have been studied or reviewed [24,46,[62][63][64][65] and their costs determined, a number of studies [34,40,45,69] have indicated most of the cost of the biofuel production process to be attributable to biomass cultivation and harvesting. Conversion to biofuel from the intermediate product appears to add little to the biofuel cost, although optimisation of harvesting, oil extraction and biodiesel production has been calculated to reduce the BESP by up to 41% depending on the precise process technologies employed [69].…”

“…Whilst this provides a further energy benefit, the overall cost benefit appears to be marginal [21] unless the AD technology is already installed on site and has spare capacity. A consideration of integration of MCT with the power plant providing the CO 2 from the flue gas revealed that, for a standard photosynthetic efficiency of 4% the algal biomass value was 24-26% higher than the BESP irrespective of the power plant technology [24].…”

“…Within this general scope there have been many different approaches to quantifying the cost benefit. The most common of these involve determination of the required cost (or the break-even selling price, BESP) of either the algal biomass or the derived biofuel for overall cost neutrality [19][20][21][22][23][24], and within this scope many parameters have been examined.…”

“…Impact of regional decentralisation of processing facilities on cost [24] PBR technology (OP & PBR); Power plant technology (3 types); irradiation intensity; CO 2 fixation rate.…”