Optimisation of Tray Drier Microalgae Dewatering Techniques Using Response Surface Methodology

Abstract

The feasibility of the application of a tray drier in dewatering microalgae was investigated. Response surface methodology (RSM) based on Central Composite Design (CCD) was used to evaluate and optimise the effect of air temperature and air velocity as independent variables on the dewatering efficiency as a response function. The significance of independent variables and their interactions was tested by means of analysis of variance (ANOVA) with a 95% confidence level. Results indicate that the air supply temperature was the main parameter affecting dewatering efficiency, while air velocity had a slight effect on the process. The optimum operating conditions to achieve maximum dewatering were determined: air velocities and temperatures ranged between 4 to 10 m/s and 40 to 56 °C respectively. An optimised dewatering efficiency of 92.83% was achieved at air an velocity of 4 m/s and air temperature of 48 °C. Energy used per 1 kg of dry algae was 0.34 kWh.

Cyanobacteria as a Promising Alternative for Sustainable Environment: Synthesis of Biofuel and Biodegradable Plastics

“…This dewatering process can be performed either by addition of bioflocculants (usually bacterial cells) in the cyanobacterial culture, which saves the additional costs of chemical flocculants, but increases the chances of contamination and interference with cyanobacterial metabolic processes, or another efficient technology of forwarding osmosis could be employed that works on creating a pressure gradient across a semi-permeable membrane. This method is highly efficient and can recover cyanobacterial cells from dilute cultures as well (Anyanwu et al, 2018 ).…”

“…These include maintenance of optimal growth conditions throughout the culture until the harvest, fine-tuning the metabolic needs of strains, various aspects of boosting biosynthesis efficiency, biomass production (Lau et al, 2015 ), and efficient pre-treatment optimization with least emissions and high yield (Khan et al, 2018 ) along with the process of dewatering (Anyanwu et al, 2018 ). Other issues include analysis of nutrient consumption rate and its flux and continuous mining of efficient indigenous strains with better photosynthetic efficiency and higher productivity.…”

Factors Affecting Microalgae Production for Biofuels and the Potentials of Chemometric Methods in Assessing and Optimizing Productivity

“…The growth of the microalgae biofuels industry was promoted by the opportunities for GHG mitigation through CO 2 capture using microalgae and the development of biofuel policies globally [29,30,31]. However, the key challenge to processing microalgae is the need for dewatering prior to conversion, which requires high amounts of energy and constitutes a significant processing cost, accounting for 20–30% of the total production cost [32]. These as well as other processing constraints have kept microalgae biofuels production technically possible but not economically feasible.…”

Drying process optimization and kinetic study of sugarcane filter cake using a pilot-scale rotary dryer

“…RSM is one of the tools for predicting 2-3 factors in a study. In the eld of drying, there are several articles that used RSM in different con gurations [30][31][32][33][34]. However, there is no drying model for sugarcane lter cake.…”