Grantee Research Project Results

Innovations in Vapor Phase Bioreactor Design

EPA Grant Number: R826168
Title: Innovations in Vapor Phase Bioreactor Design
Investigators: Kinney, Kerry A.
Institution: The University of Texas at Austin
EPA Project Officer: Hahn, Intaek
Project Period: December 1, 1997 through November 30, 2000
Project Amount: $293,809
RFA: Exploratory Research - Environmental Engineering (1997) RFA Text | Recipients Lists
Research Category: Safer Chemicals , Land and Waste Management

Description:

The purpose of the proposed research is to develop an efficient, vapor phase bioreactor that will reliably treat VOC-contaminated air streams over long periods of time. Conventional vapor phase bioreactor systems do not adequately control several important operating parameters such as biomass distribution, biomass activity and nutrient/moisture levels within the biofilm. These simple systems work acceptably during short term tests in the laboratory but fail to ensure reliable performance in the field where process variables fluctuate widely. In this study, the following three design features will be investigated for their ability to overcome several key problems that inhibit the reliable performance of vapor phase bioreactors:

Directionally-switching operation (to improve biomass distribution and prevent clogging);
Slip stream feed (to maintain high biomass activities even during periods of little or no contaminant feed); and
An aerosol system (to efficiently deliver nutrients and moisture to the biofilm).

Approach:

Four, laboratory-scale, vapor phase bioreactors will be constructed that incorporate each of the bioreactor design innovations described above. During the first phase of the study, the directionally-switching parameters required to control biomass accumulation and distribution will be determined. During second study phase, the effectiveness of the slip stream to maintain high biomass activity during continuous operation as well as during system shutdowns will be evaluated. The final study phase will be devoted to optimizing the aerosol nutrient and moisture delivery system. To make the study results broadly applicable, the effectiveness of each of these design modifications will be determined for a bioreactor packed with inert media as well as for a bioreactor packed with a natural, compost-based material.

Expected Results:

Vapor phase bioreactors have the potential to treat air streams contaminated with VOCs in a cost-effective and efficient manner. Unlike other air pollution control technologies, vapor phase bioreactors are relatively "clean" systems that do not consume large amounts of energy or generate undesirable byproducts. Successful optimization of the three design innovations will allow greater control of several important operating parameters and, ultimately will result in more stable and efficient bioreactor performance. Particularly for small businesses, an inexpensive, low-risk, and reliable vapor phase bioreactor will make it much easier to comply with increasingly stringent control requirements for VOC emissions.

Publications and Presentations:

Publications have been submitted on this project: View all 15 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 4 journal articles for this project

Supplemental Keywords:

air pollution, VOCs, innovative technology, biofilter, biotrickling filter, biomass control, biomass activity, nutrients., Air, Scientific Discipline, Environmental Chemistry, Engineering, Chemistry, & Physics, air toxics, Environmental Engineering, air sampling, biofilms, biofiltration systems, biotrickling filters, chemical treatment, treatment, vapor phase bioreactors, innovative technologies, atmospheric particles, cost effective, emission control technologies, environmental contaminants, biomass, VOCs, directionally-switching parameters

Progress and Final Reports:

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.