Nontoxic Sparker Control of Zebra MusselsEPA Contract Number: 68D02059
Title: Nontoxic Sparker Control of Zebra Mussels
Investigators: Schaefer, Raymond B.
Small Business: Phoenix Science and Technology Inc.
EPA Contact: Richards, April
Project Period: June 1, 2002 through June 1, 2004
Project Amount: $225,000
RFA: Small Business Innovation Research (SBIR) - Phase II (2002) Recipients Lists
Research Category: Watersheds , SBIR - Water and Wastewater , Small Business Innovation Research (SBIR)
Description:Zebra mussels are a nonindigenous aquatic nuisance that now extends from the Great Lakes to the mouth of the Mississippi River. Zebra mussels clog intake pipes, screens, cooling systems, and so on, and are a serious problem. The Nonindigenous Aquatic Nuisance Prevention and Control Act and Amendments mandate control of zebra mussel infestations. Chlorine effectively controls zebra mussels but produces disinfectant by-products, some of which are carcinogenic. Many alternative technologies have been attempted, but a viable means of effectively managing zebra mussels has not been demonstrated.
Sparker technology is a potential nontoxic control method. Sparkers emit pressure pulses that can prevent the growth of new zebra mussels and clear away adult zebra mussels. However, the only commercial sparker is not widely used because of effectiveness questions, the need to replace electrodes frequently, and a high capital cost. Phoenix Science & Technology, Inc., has developed innovative sparker sources with high efficiency, proprietary electrodes, and acoustic reflectors. The objective of this Phase II project is to develop a new low-cost, long-lifetime sparker system with proven zebra mussel control capabilities.
The feasibility of sparker control was demonstrated in Phase II. Field tests at two water intake pipes determined the pressure levels needed to control zebra mussels, and for the first time determined the control range of a sparker. In laboratory experiments, Phoenix Science & Technology, Inc., demonstrated how to increase electrode lifetime by a factor of four and designed a conceptual low-cost sparker.
The proposed Phase II project, in concert with an outside investment by the U.S. Army Corps of Engineers, is a comprehensive program to develop a new sparker system that will provide proven, nontoxic, cost-effective control of zebra mussels. Phase II will address remaining questions about pressure requirements, pulse propagations in pipes, and optimizing utilization of sparker pulses with acoustic reflectors. A new sparker with high-efficiency and long-lifetime electrodes will be designed, built, and field tested. The sparker also will be tested in a new field configuration that is expected to provide complete control of zebra mussels for intake pipes of all lengths. A successful Phase II project will produce a prototype sparker with low life-cycle cost that will lead to commercialization. The sparker also will be useful for other biofouling problems, such as aquatic nuisance species in ballast water (see U.S. Environmental Protection Agency Office of Water 4504F Fact Sheet), removal of algal colonies, and bacterial growth.