In this study, the authors conducted a battery of toxicity tests using photo bacterium, algae, crustacean and fish to evaluate acute toxicity profile of coking wastewater, and to evaluate the performance of a novel wastewater treatment process, vertical tubular biological reactor (VTBR), in the removal of toxicity and certain chemical pollutants. A laboratory scale VTBR system was set up to treat industrial coking wastewater, and investigated both chemicals removal efficiency and acute io-toxicity to aquatic organisms. The results showed that chemical oxygen demand COD) and phenol reductions by VTBR were approximately 93% and 100%, respectively. VTBR also reduced the acute toxicity of coking wastewater significantly: Toxicity Unit (TU) decreased from 21.2 to 0.4 for Photobacterium phosphoreum, from 9.5 to 0.6 for Isochrysis galbana, from 31.9 to 1.3 for Daphnia magna, and from 30.0 to nearly 0 for Danio rerio. The authors concluded that VTBR is an efficient treatment method for the removal of chemical pollutants and acute bio-toxicity from coking wastewater.
Authors: Zhou S, Watanabe H, Wei C, Wang D, Zhou J, Tatarazako N, Masunaga S, Zhang Y. ;Full Source: Ecotoxicology & Environmental Safety. 2015 Feb 20;115C:217-222. doi: 10.1016/j.ecoenv.2015.02.017. [Epub ahead of print] ;