Design and Implementation of Air Extraction using the Odor Capture Performance for the Containment of Odors

The complete containment of odorous gases is often challenging, partly because containment is difficult to quantify and subject to ever changing conditions like wind. Moreover, odor containment covers inevitably have openings for access requirements. Openings are also created from wear and tear of covers and seals over time and sometimes because of poor installation and limited quality control checks. This paper focusses on the design of the air extraction system (ventilation, ductwork and covers) to obtain near complete odor containment. The paper outlines a practical method for setting ventilation targets for covered process units, using easily obtained input data. The new concept introduced here is referred to as the “Odor Capture Performance”, which can be used as a tool for the design and the implementation of air extraction systems. The Odor Capture Performance has been taken to be the percentage of time (percentile) that an air extraction system provides sufficient extraction from a covered area to eliminate fugitive odor emissions. The Odor Capture Performance can be calculated and essentially only requires three input parameters: the measurement of the negative pressure and the air extraction rate at the covered process unit, and regional wind speed data. A case study has been used to illustrate the concept.