Air-breathing tube photobioreactor

The invention discloses an air-breathing tube photobioreactor which comprises a tube photobioreactor and a cylindrical alkaline fuel cell stack, wherein the tube photobioreactor comprises photoreaction tubes, a liquid storage tank and a circulating water pump; alga liquid is driven by the circulating water pump to flow in the photoreaction tubes and the liquid storage tank in cycle; and cylindrical alkaline fuel cells are arranged at the connected part between the photoreaction tubes. The alga liquid with high dissolved oxygen content in the photobioreactor is treated by using cathodic oxygen reduction reaction of the fuel cells, a traditional aeration device of the tube photobioreactor is not needed under the condition of ensuring efficient culture of the alga liquid, meanwhile, the fuel cells carry out anodic oxidation to generate CO2 as a carbon source of the alga liquid and the generated electric energy can be used as a power source of an additional light source, thereby achieving the target of reducing t