A CIRCULATORY PHOTOSYNTHETIC BIOREACTOR IS PROVIDED. THE CIRCULATORY PHOTOBIOREACTOR COMPRISES A FIRST CULTIVATING PART (100), A HEAT EXCHANGER (200) AND A SECONDARY CULTIVATION PAR (300). THE SECONDARY CULTIVATING PART (300) IS SCALABLE SO THAT VOLUME OF THE CULTIVATION CAN BE ADJUSTED. FURTHER, THE SCALABLE CIRCULATORY PHOTOSYNTHETIC BIOREACTOR SHORTEN THE CULTIVATION PERIOD COMPARED WITH CONVENTIONAL CIRCULATORY PHOTOSYNTHETIC BIOREACTORS AND SUITABLE FOR MAINTENANCE. FIGURE 1