Kazan National Research Technological University, Kazan, Russia:

F. Yu. Akhmadullina, Senior Lecturer, Department of Industrial Biotechnology, e-mail: ilc2013@inbox.ru
E. S. Balymova, Associate Professor, Department of Industrial Biotechnology, Candidate of Technical Sciences, e-mail: ilc2013@inbox.ru
R. K. Zakirov, Associate Professor, Department of Industrial Biotechnology, Candidate of Technical Sciences, e-mail: zakrus@mail.ru

Electroplating industry is a source of highly toxic waste containing heavy metals. Minimization of the related environmental risks is associated with the implementation of a combination decontamination process, which will ensure a thorough decontamination of waste and reduce environmental charges. The proposed decontamination process is based on the use of reagents in combination with biotechnology. Because of their biological inertness, the sorption ability on the flakes of activated biomass, as well as high toxicity, heavy metals can be referred to hidden factors that can disrupt the operation of a biological treatment plant and, as a consequence, impact the quality of biotreated wastewater. Preventative measures are necessary to minimize and eradicate such impact, which would involve a thorough elimination of heavy metals from effluents. One solution can be sorption treatment of metal-containing effluents after they have been treated on-site. The paper considers using excessive activated sludge, which forms in the course of biological treatment, as a biosorbent. This would help further reduce costs related to the disposal and storage of biosludge. A series of experiments was carried out to understand the sorptive capacity of biosludge in relation to certain heavy metal ions. Sorption isotherms were obtained that indicate the sorption performance of activated sludge flakes for biochromate ions and chromium (III) and nickel (II) ions. The paper demonstrates that excessive biomass can actually be used for thorough elimination of metals from effluents that have been treated on-site. The authors describe an advanced high-performance combination process for the treatment of sewage water together with metal-containing effluents generated by electroplating industry.

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