Hazen and Sawyer is a leader in the design of odor control facilities for sludge and wastewater treatment projects, having been responsible for state-of-the-art odor control systems installed around the world. Our process specialists routinely advise clients on process modifications with the aim of achieving better odor control; improved effluent quality; increased efficiency in power, labor, or chemical usage; and enhanced sludge handling. Experience has taught us that there are three general approaches to developing an odor control program: elimination of the odor source, elimination of the odor perception, and treatment of the odor.
While the sources of wastewater treatment plant odors cannot be completely eliminated, they can be minimized through good housekeeping, proper facilities design and operation, and control of discharges. Elimination of the odor perception refers to the dilution of odors with fresh air, or masking the odor by superimposing a more pleasant aroma. The efficacy of masking is often uncertain with respect to public acceptance, and the process tends to be high in chemical cost. Treatment of the odor at its source is usually the necessary approach for odor control at wastewater treatment plants. This can be achieved through technologies such as carbon adsorption and wet scrubbers to treat off gases, and the installation of covers on tanks and chambers that process wastewater, to contain odors and prevent their dispersion.