Water Environment & Technology (WE&T) is the premier magazine for the water quality field. WE&T provides information on what professionals demand: cutting-edge technologies, innovative solutions, operations and maintenance, regulatory and legislative impacts, and professional development.
What’s Old Is New Again
Ozone is gaining greater prominence as interest grows in microconstituent removal, water reuse
Although ozone has been used to treat water for more than 100 years, it did not receive widespread use in the United States until the late 1970s and early 1980s, when both drinking water and wastewater treatment facilities began to use it as a disinfectant. However, as the use of ozone increased, utilities were drawn to its oxidant and microflocculation properties. Due to recent research showing that ozone can be effective in removing some microconstituents, there has been a resurgence of interest in using ozone for drinking water and wastewater treatment, as well as water reuse.
A planning tool for selecting wastewater treatment technologies
Most large communities have sufficient economic and technical resources to ensure that the new facility planning process adequately matches their needs with the wide range of available treatment technologies. Smaller communities however, frequently lack either the economic resources or technical expertise to support a facility planning process that examines the broadest range of appropriate treatment technologies. Frequently, the consultants, public works staff, and community decision-makers have training or experience with only a limited range of “conventional” treatment technologies, and the facility planning process fails to consider a wide range of potentially applicable alternative technologies.
Biosolids Technologies in the Environmental Age
The SlurryCarb® facility commissioned in June in Rialto, Calif., is designed to process 245,000 Mg (270,000 ton) of biosolids from five Southern California municipalities — Orange County Sanitation District; the Sanitation Districts of Los Angeles County (LACSD); and the cities of Riverside, San Bernardino, and Rialto. The expected output is 54,000 Mg (60,000 ton) of renewable fuel, called E-fuel, that is expected to generate 823,000 million kJ/yr (780,000 million Btu/yr). Based on average U.S. household consumption, this is enough energy to power 8000 homes.
Independent evaluation by Environmental Resources Management (Annapolis, Md.) concluded that the use of E-fuel would reduce annual greenhouse gas emissions by more than 73,000 Mg (80,000 ton).
The Rialto facility is one of several new installations designed with sustainability in mind.
“The biosolids market is currently in the early phases of repositioning itself to the new world of global warming, carbon credits, green energy, and sustainability,” said Peter Brady, president of Alpine Technology Inc. (Austin, Texas) and co-chair of the Water Environment Federation (Alexandria, Va.) Residuals and Biosolids Committee. The “rule of thumb,” he said, is to “follow full-scale site performance data over a period of time and several projects.”
Some pioneers are testing and evaluating these new technologies as part of their environmental ethic.
Coming in the next issue:
Two-thirds of the challenge in effective wastewater treatment is collecting and transporting the water from where it’s generated to where it’s cleaned. To that end, find out how green infrastructure projects are emerging as a complementary technology to deep-tunnel storage and conveyance systems for curbing CSOs and SSOs. Making the most of rehabilitation dollars is also a must; read about how the proper application of assessment technologies makes the investment in system rehabilitation more cost-effective. Pumps and force mains form a third part of the transport issue; so don’t miss the second part of the article “How to Troubleshoot an Underperforming Pump Station.”
Also in this issue:
- In Search of a Sustainable Future: Population, water issues prompt southern Florida to expand water reuse.
- Thinking Inside the Box: Using a shipping container as a low-cost alternative to traditional building construction.
- Worried About Wireless Networks? Today’s technologies and practices provide much better security.