天津大学研究生e-Learning平台

Energy penalty of solvent regeneration in CO₂ absorption process is a critical challenge. To avoid the energy consumption, novel ammonia absorption-microalgae hybrid CO₂ capture process has been designed in this work. In the proposed process, the conventional desorption column is replaced by a microalgae cultivation system. As a result, the NH₄HCO₃ could be utilized as nutrient for microalgae growth and converted into biofuel or value-added ingredients. Meanwhile, the challenge of ammonia escape could be avoided via high purity ammonia recycling in the hybrid process. In the detail, three Chlorella sp. (L166, L38 and UTEX1602) are used as the candidate algae for the hybrid process, and two different nitrogen source in four cultivation modes (NaNO₃, NH₄HCO₃, NH₄HCO₃ assisted with 5% CO₂ and NH₄HCO₃ via fed-batch) are tested to find the optimal conditions. The experiment results indicated that the selected Chlorella sp. L166, L38 and UTEX1602 could be potential microalgae to be used in chemical-biological hybrid CO₂ capture and utilization process with carbon fixation efficiency over 85%. The above results also indicated that the novel absorption-microalgae hybrid process could be a promising alternative to the conventional CO₂ absorption technology.