Studying the efficiency of the multiple biofilters in the reduction of pollutants from wastewater

Abstract

The Microorganisms: yeast Sporobolomyces yunnanensis, Rhodotorula mucilaginosa and Kluyveromyces marxianusin growth of 184× 106 ± 15 cell\ml, and bacteria Pseudomonas aeruginosa and Bacillus cereus in the growth of 9 – 15× 108 ± 5 cell\ml, and algae Chlorella vulgaris in the growth of 45 × 105 ± 5 cell\ ml were selected as a bio filter to reduce organic and nonorganic pollutants from wastewater by COD, TOC, TN and TP concentrations of 455, 151, 9.5 and 31 ppm in treatment period 4, 6 and 18 hr. and pH of 7-8 in 25 Co as a Batch culture system. The yeasts showed ability to reduce COD concentration by 50-64% in 18 hr. treatment period, and the bacteria showed the ability to reduce COD, TOC, TN and TP concentrations by 59-69%, 57-66%, 53-63% and 40-55% in 18 hr. treatment period. At the same time, algae showed efficiency in reducing TN and TP by 81, 82%. The selective microorganisms showed high efficiency as a biofilter to reduce pollutants concentrations from wastewater in three serial steps by a treatment period of 6 hr in each step with a high ability to reduce COD, TOC, TN , and TP concentrations by 83, 91, 100, and 100% in 18 hr. treatment period. Ultimately, this study demonstrated the high efficiency of the multiple biofilters consisting of bacteria, yeasts, and algae in reducing the concentration of pollutants in sewage wastewater. Keyword. Multiple biofilters, Bacteria, Yeast, Algae, COD, TOC, TN.