Full-scale bioreactor pretreatment of highly toxic wastewater from styrene and propylene oxide production

Linh Dao, Tatiana Grigoryeva, Alexander Laikov, Ruslan Devjatijarov, Olga Ilinskaya
2014 Ecotoxicology and Environmental Safety  
The wastewater originating from simultaneous production of styrene and propylene oxide (SPO) is classified as highly polluted with chemical oxygen demand level in the range 5965 to 9137 mg L À 1 -as well as highly toxic. The dilution factor providing for a 10 percent toxic effect of wastewater samples in a test with Paramecium caudatum was 8.0-9.5. Biological approach for pretreatment and detoxification of the wastewater under full-scale bioreactor conditions was investigated. The number of
more » ... ended microorganisms and the clean up efficiency were increased up to 5.5-6.58 Â 10 8 CFU mL À 1 and 88 percent, respectively during the bioreactor's operation. Isolates in the Citrobacter, Burkholderia, Pseudomonas, and Paracoccus genera were dominant in the mature suspended, as well as the immobilized microbial community of the bioreactor. The most dominant representatives were tested for their ability to biodegrade the major components of the SPO wastewater and evidence of their role in the treatment process was demonstrated. The investigated pretreatment process allowed the wastewater to be detoxified for conventional treatment with activated sludge and was closely related to the maturation of the bioreactor's microbial community.
doi:10.1016/j.ecoenv.2014.07.012 pmid:25086231 fatcat:ltvhy7r6i5gznfhguwubu7n33e