Process optimization and engineering integration of the Deployable Aerobic Aqueous Bioreactor (DAAB) system for treating municipal wastewater.

摘要

Natural disasters can cause disruption or failure to water and wastewater systems. Recent hurricanes, like Katrina, Rita, and Ike remind us that natural disasters can cause both physical damage and contamination impacts on publicly owned treatment works (CWSSR and NRC 2007). Moreover, there are some situations where centralized wastewater systems are not available or impractical such as remote communities, fairs, and war fields. There is growing interest in developing wastewater treatment systems that are easily deployable to the disaster affected areas and can serve communities until the recovery of water and wastewater facilities. Decentralized systems offer a number of benefits over centralized systems in flexibility, portability, wastewater management, ease of operation, cost effectiveness, and water reuse potential.;This study was performed to provide long-term performance of the Deployable Aerobic Aqueous Bioreactor (DAAB) system for treating municipal wastewater under typical conditions as well as in the event of shock or toxic loads. The DAAB system utilizes laboratory cultivated microorganisms in a logarithmic growth state for a quick start of the treatment system. Seven types of microorganisms were selected for inoculating in the acclimatized in the laboratory with raw municipal wastewater before inoculating in the DAAB system. A specially designed vacuum bubble technology (VBT) surface aerator was used to create micro vacuum bubbles with an average diameter of 0.25 mm in diameter (Advanced Aeration, Inc.). The DAAB system is designed as a fully deployable system; it can be housed in a standard 40-foot-long shipping container or single C-130 aircraft for transportation. The DAAB system is capable of achieving EPA discharge standards within 24 hours of deployment.;The results of the study showed that the DAAB system produced better quality effluent with 3 to 4 GPM wastewater flowrates. The average percent removals for 3 to 4 GPM wastewater flowrates were 82+/-10% and 83+/-10% for BOD5 and TSS, respectively. The DAAB system showed nutrient removal potential with average percent removals of 35% and 64% for NH 3-N and TP, respectively. The DAAB system showed some of the advantages over other biological treatment systems such as minimal chemical, energy and labor inputs, relatively easy operation and less maintenance problems. Ongoing research and developments aim at achieving water re-use application of the DAAB system effluent.