Illumination promoting biomass production in wastewater treatment for Rubrivivax gelatinosus

Abstract

In order to improve the reuse degree of Rubrivivax gelatinosus (R. gelatinosus) resource in soybean producing wastewater (SPW) treatment, the impacts of diverse illumination strength on R. gelatinosus biomass and organic contaminant abatement were discussed. It was reported that with the best illumination strength (6,000 lux), the production (3,800 mg/L) of biomass was increased by sixty percent of dark group. COD removal and protein removal rate got 85 and 80%. Influence of diverse illumination strength on R. gelatinosus growth were divided into three aspects, including illumination limitation (0−5,000 lux), illumination saturation (5,000−7,000 lux), illumination inhibition (8,000 lux or higher). Meanwhile, at 6,000 lux, bacteriochlorophyll and carotenoids contents, ATP production were increased by 200, 200, 43.9% severally. Appropriate illumination improved ATP production by increasing the generation of bacteriochlorophyll and carotenoids in photosynthesis. Augment of energy production provoked the biomass production and wastewater treatment. Nevertheless, low or high illumination strength was un-advantage for R. gelatinosus growth due to the illumination deficiency or restrian. Moreover, 6,000 lux shortened the treatment time from 96 h to 48 h.