Huang and Myoda Win Horner Award for Paper Documenting Novel Water Treatment Method

By Diane S. Kukich

Chin-Pao Huang, Donald C. Phillips Professor, and Samuel P. Myoda (PhDEnvE2001) have been selected by the Environmental Water Resources Institute (EWRI) to receive the 2008 Wesley W. Horner Award for their paper “Sonochemical Treatment of Wastewater Effluent for the Removal of Pathogenic Protozoa Exemplified by Cryptosporidium.”

The paper documents the researchers’ development of a treatment method that uses ultrasonic waves to remove pathogenic protozoa such as Cryptosporidium and Giardia from water supplies. These microscopic parasites can cause serious outbreaks of intestinal illness when contaminated water is ingested.

“To meet the increasing demand for potable water, it is essential that reuse and reclamation projects be developed and implemented to augment water sources,” Huang says. “The reuse of treated wastewater could provide a significant portion of the demand for clean water if we can successfully deal with microbial and chemical contamination.”

“Pathogenic organisms such as Cryptosporidium and Giardia pose a potential threat to public health,” he continues. “These parasites can withstand typical disinfection processes such as chlorine-based systems. Typically, the chlorine dose can be increased to eliminate the pathogens, but there is a trade-off in treatment strategies.” 

Using large doses of chlorine to eliminate the biological contaminants increases unwanted disinfectant by-products, known as DPBs, raising other health concerns.  On the other hand, using reduced rates of chlorine to minimize DBP formation can lead to a larger population of potentially dangerous microorganisms. 

The alternative process developed by Huang and Myoda sends waves of ultrasound through water samples, creating hydroxyl radicals that can render bacteria and protozoan pathogens inactive. A preliminary study was carried out to assess the effectiveness of the technology.

“We found that a number of factors had an effect on ultrasonic destruction of Cryptosporidium,” Huang says, “including the density of the pathogen population, pH, and ultrasonic energy intensity.  But overall, the method shows promise as an effective low-cost disinfection technology that works quickly and requires no pretreatment or temperature control.”

The Horner Award has been given by EWRI, a branch of the American Society of Civil Engineers (ASCE), since 1968 to recognize excellence in journal papers in the areas of “hydrology, urban drainage, and sewerage.”  In selecting Huang and Myoda’s paper, the committee noted its contribution to the field of environmental engineering. 

The paper was published in the April 2007 issue of Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management.