Biofixation of CO_2 from synthetic combustion gas using cultivated microalgae in three-stage serial tubular photobioreactors

摘要

Coal is the most abundant of the fossil fuels, with reserves estimated at 10~2 billions of tons. The feasibility of using coal as a fuel depends upon reducing emissions of gas when it is burnt, such as carbon dioxide (CO_2), sulfur oxides (SO_x), and nitrogen oxides (NO_x). The removal of CO_2 with microalgae may be one of the most effi cient ways of reducing this gas, without the need for radical changes in the world's energy supply and production methods. Spirulina sp. LEB-18 and Scenedesmus obliquus LEB-22 were cultivated in serial tubular photobioreactors, with the aim of measuring the potential of CO_2 biofi xation and the resistance of the microalgae to SO_2 and NO. Spirulina sp. and S. obliquus had CO_2 biofi xation scores of 0.27 and 0.22 g L~(-1) d~(-1), respectively. Both microalgae were resistant to SO_2 and NO, and grew during the 15 d they were cultivated, which proves that using microalgae is an effi cient method of biofi xation of CO_2 emitted when fossil fuels are burnt.