Nature Environment and Pollution Technology

A. R. Vinod ¹, R. M. Mahalingegowda ²

Affiliations
1 Department of Environmental Engineering, P. E. S. College of Engineering, Mandya-571 401, Karnataka, IN
2 Department of Civil Engineering, P. E. S. College of Engineering, Mandya-571 401, Karnataka, IN

Abstract

Recent interest in environment-friendly materials for the treatment of wastewater leads to the creation of new composites. Organic matter can be effectively removed by packed materials such as plastic honey comb structures, corrugated sheets, stones, etc. in attached growth process. The use of naturally available fibrous materials, which is cost effective and also have characteristics of high specific surface area can be used as a support media in fixed film reactor. Several natural fibrous biomass support mediums are available for use; some of these are coffee husk and wooden chips. The present investigation aims to study the applicability of coffee husk blended with wooden chips as a fixed bed, and also to study the removal efficiency of chemical oxygen demand (COD), phosphate and ammonia nitrogen (NH₃-N) from the municipal wastewater. Two phases of operation were conducted to study the effects of hydraulic retention time (HRT), mixed liquor suspended solids (MLSS) and organic loading rates (OLR). In this study the experiment was conducted for a continuous mode of operation. The bioreactors were continuously aerated and fed with institutional wastewater having an initial average COD of 669 mg/L, ammonia nitrogen of 2.9 mg/L, phosphate of 19.83 mg/L, and TSS of 3600 mg/L. The reactor filled with coffee husk blended with wooden chips showed nominal amount of COD removal of 88-91%, ammonia nitrogen removal of 70-73% and phosphate removal of 91- 94% under different reactor conditions.

Keywords

Fixed Film Reactor, Wastewater Treatment, Coffee Husk, Wooden Chips.

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A. R. Vinod ¹, R. M. Mahalingegowda ²

Affiliations
1 Department of Environmental Engineering, P. E. S. College of Engineering, Mandya-571401, Karnataka, IN
2 Department of Civil Engineering, P. E. S. College of Engineering, Mandya-571401, Karnataka, IN

Abstract

The present investigation was aimed to study removal of COD and NH₃-N in two fixed bed reactors, one filled with fibrous coconut coir and the other with alternate pebble bed with corrugated sheets. The experimental study was conducted for a batch mode of operation. The bio-reactors were continuously aerated and fed with hostel sullage having an initial average COD of 890 mg/L and NH₃-N of 70 mg/L. The reactor with coconut coir showed appreciable amount of COD removal of 79% to 84% and nitrification of 56% to 71% for a detention period of 4-16hrs. The reactor with alternate pebble bed with corrugated sheets showed COD removal of 70% to 75% and NH₃-N of 50% to 65%. The use of various fixed beds having higher surface area is effective in removing COD and nitrogen levels in domestic sullage with high organic impurities. Fibrous materials like coconut coir seem to be a promising option in removal of COD and NH₃-N comparing to conventional attached growth bed such as pebble bed along with corrugated sheets.

Keywords

Wastewater Treatment, Fixed Bed Reactors, Fibrous Coconut Coir, Corrugated Sheets.

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