Abstract
The research results describe the pilot production of microalgae biomass – Spirulina, especially in wintertime, using the geothermal energy of water to save the costs for heating of the pool photobioreactor and biomass drying box. For carrying out of the process a simplified nutrient medium consisting of geothermal water and salts: sodium bicarbonate, potassium nitrate, diammonium phosphate, and urea was developed. The conditions for the Spirulina biomass cultivation in wintertime were optimized. The technical and economic feasibility and conditions for large-scale production of Spirulina in Kazakhstan for commercial purposes are justified. It has been shown that the Spirulina biomass may serve as a feedstock for the production of biodegradable surfactants.