Flotation treatment of phenolic wastewater in a biochemical unit of the coke and by-product process

Summary

In 2014 the construction of a unique unit for biochemical treatment of wastewater from coke and by-product process at the «Novolipetsk Steelworks» OJSC was finished. EKOTON flotation units used in the process of removing tar and oils from the recycling phenol wastewater have been specially designed for the application in this industry and provide for 97.5% treatment level in relation to the main parameters. The results of the laboratory studies and full-scale tests of phenolic coke wastewater treatment by chemical dissolved air flotation are presented. The specialists of «EKOTON» Company have selected the parameters of the process equipment and improved the design of the flotation unit; determined the main parameters of physical-and chemical treatment of phenolic wastewater with due account for the wastewater composition, high temperature, limits of the tar and oil concentrations in the mixtures discharged from the flotation unit. The experimental data allowed developing the regulations for operating flotation units for coke and by-product process with the use of chemical treatment of phenolic wastewater. The novelty and singularity of the treatment processes introduced at the wastewater treatment facilities of «NMLK» OJSC provided for installing the completely sealed utilities and tanks above the ground to eliminate any possible underground water pollution and reduce air emissions. In 2015 after industrial-scale testing «EKOTON» flotation unit was commissioned as a part of the biochemical unit of the coke and by-product process.

Key words

coagulant , flocculant , pressure flotation , coking plant , biochemical treatment unit , flotation unit , phenolic water