Determination of the Optimal and Economical Biofilter Depth in an Anaerobic Hybrid Reactor for Treating Livestock Industrial Wastewater

Abstract

A laboratory scale anaerobic hybrid reactor (AHR) being comprised of UASB and anaerobic biofilter was used to study the different biofilter depth with corresponding different critical HRT (1) and HRT (2) in treating livestock industrial wastewater, where the critical HRT (1) was defined as the HRT which resulted in the total COD in the effluent of the AHR exceeding in the influent at unsteady state, and the HRT (2) was defined as the HRT which resulted in the total COD in the effluent of the AHR exceeding the quality standard for discharging to sewer (in Hong Kong is Total COD < 1000 mg L¹) at steady state. Two formulas expressing the relationship of different biofilter depth in the AHR and it's critical HRT (1) and HRT (2) in treating livestock industrial wastewater were obtained and used to design optimal and economical biofilter depth in a full scale AHR for treating livestock industrial wastewater on site. The performance of the full scale AHR indicated that using the experience formulas to design the optimal and economical biofilter depth in the full scale AHR for treating livestock industrial wastewater was successful. Experimental results also showed that the biofilter in the full scale AHR had not only physical filtration effect, but also had powerful biodegradation capability, furthermore, at unsteady state, the effect of biofilter on pollutant degrading in the full scale AHR was more great.

Keywords:

• Anaerobic hybrid reactor
• Biodegradation
• Biofilter
• Critical HRT
• UASB
• Wastewater treatment