PURE OXYGEN FOR PURE AIR AT WASTEWATER TREATMENT PLANTS

High purity oxygen has been injected into force mains in wastewater collection system for many years. The injection of oxygen into wastewater streams within treatment plants specifically for odor abatement, however, has been done in only very limited applications. This paper presents the details and results of a pilot study in which pure oxygen was injected into 40-MGD raw wastewater stream in an existing in-plant force main at a large regional wastewater treatment plant to minimize the release of odorous compounds from preliminary and primary treatment areas. The use of high purity oxygen represented a potentially lower cost alternative to the traditional covering and scrubbing option. In addition to lower cost, eliminating covering and scrubbing would eliminate the significant maintenance and personnel safety issues associated with maintaining equipment and structures under covers. Results of the pilot study showed that the use of pure oxygen for odor control could be both effective and safe. The final planning level cost evaluation showed the pure oxygen odor control system to be significantly less costly from an initial capital investment perspective and cost competitive with alternative odor control options from an operations and maintenance perspective.