Experiment Research On Performance Of Bioreactor For Light Guiding Of Solar Energy Light Inside

There are two kinds of photobioreactors for the cultivation of microalgae, open system and closed one. They have their own advantages and disadvantages respectively. The closed one has high utilization rate of light energy and high cultivate density with controlled cultivation condition, but it’s structure is complicated, and the cost is high, so is difficult to be commercialized. The open one has simple structure and low cost, it is easy to be commercialized, but it’s light energy utilization rate is low, and the density of cultivation is small. After study we realize that we can combine the advantages of both. Based on the open raceway pond the characteristics of high ratio of surface area to the volum in the closed bioreactor is integrated to open pond, which means putting simple structure grooves for light guiding to the open pond.Three different grooves for light guiding are designed and the light transmission law inside the grooves are theoretically and experimentally explored. Firstly, with software LightTools and Tracepro, a parallel light beam is put on three models of the grooves, in different incidence angles. The light transmission law, that is transmission ratio of light ray and the radiation distribution in the bottom of grooves, is explored. By theoretical calculation and computer simulation, the changes of the relative concentration rate of grooves and radiation distribution in the bottom of grooves with respect to the angle between normal line of box and vertical line of ground are found. At last, there is a comparison about light intensity between outside and inside of the bioreactor grooves to verify light transmission and the performance of the groove. The experiment result shows that it is quite well consistent with the theoretical analysis and computer simulation. Sometimes, the bottom of the light intensity is even higher than the outside light intensity.