Challenge

Hyperion Wastewater Treatment Plant is located next to the Los Angeles International Airport in a densely populated urban environment. Throughout the 1980’s, the City used conventional packed tower systems and activated carbon adsorbers to treat odors. Plant operations generated odors resulting in more than 60 individual scrubbing units across the plant, each varying in size and design.

Knowing that the plant’s odor control equipment would eventually need to be replaced, the City conducted an odor control testing program. The purpose - to select the next generation of odor control equipment that would provide the city with improved odor control and reduced cost.

Solution

The City conducted an exhaustive evaluation of all available odor control technologies, including:

• Single-stage packed towers
• Activated carbon adsorption
• Incineration
• Catalytic carbon adsorption
• Formulated media bio-trickling filters
• Two-stage packed towers
• Multi-stage packed towers
• Solid dual-media (activated carbon and potassium permanganate impregnated activated alumina) adsorption

The Siemens Water Technologies LO/PRO® odor control system outperformed all other technologies in terms of:

• Odor control effectiveness - H₂S removal efficiencies greater
   than 99.5 percent
• Operating cost
• Space efficient design

Results

The first full-scale, three-stage LO/PRO® system was installed at the plant to treat odors from the primary effluent channel. Key benefits:

• Projections showed LO/PRO® design would save Hyperion $240,000 annually in chemical costs
• System very effective in controlling odors
• The Environmental Engineering Division (EED) adopted the LO/PRO® system as the basis of design for their future designs

Next Step - develop a program to standardize and centralize their odor control equipment to achieve:

• Reduced number of individual odor control stations
• Better automation of their operation
• Significant cost savings by reducing the number of purchasing contracts, spare parts inventory, field operators, and maintenance time

Based on the success of the LO/PRO® system, Los Angeles purchased six, 20,000 CFM LO/PRO® odor scrubbers for the Hyperion WWTP.