News from Schwing Bioset

Positive Results From Schwing Bioset Stabilization System

Case Study: Hollywood, FL

The South Regional wastewater treatment plant (WWTP) is owned by the city of Hollywood, Florida, primarily serving Hollywood and surrounding communities. The South Regional WWTP is an activated sludge facility that produces 60 tons of dry solids per day. The sludge is dewatered with six 2 meter Andritz belt filter presses to approximately 16 % total solids.

Sludge was being disposed at regional landfills until Florida changed its environmental regulations to protect the Okeechobee/Everglades watershed and to encourage reuse of biosolids. This substantially increased fees for disposing of biosolids.

The South Regional WWTP installed an alkaline stabilization facility in the 1990s, but it was decommissioned when neighbors complained about the odor and noise.

The retrofit of the Schwing Bioset stabilization system required demolition of all of the legacy equipment save the truck loading equipment and the lime handling equipment, which consisted of two 3500 cubic foot bulk storage silos and a pneumatic conveyance system.

Installation proceeded close to schedule; the only surprises were hurricanes Francis, Ivan, and Jeanne, as well as a pneumatic lime system that proved to need an overhaul of the rotary and diversion valves, replacement of the silo dust collectors, and replacement of silo isolation knife gate valves.

The facility has been in operation since February 2005 and over 200,000 wet tons of biosolids have been processed to a very positive response: fugitive dust and sludge spills, as occurred with the earlier equipment, are gone, and the new Bioset equipment controls odors. It’s gone so well that the disposal contract has been renewed for the next 5 years.

South Regional wastewater treatment plant

Tags: Biosolids Processing, Water Environment Federation (WEF), Biosolids, Wastewater Treatment

Biosolids in the Future

Mankato, MN: The Future of Biosolids

Mankato, MN, a small city in southern Minnesota, was recently recognized by the National Biosolids Partnership with environmental management system (EMS) Certification. Mankato’s wastewater treatment facility is the first organization in Minnesota and the 28th in the nation to achieve this certification.

Some of the benefits Mankato has seen from the EMS process include:

  • Energy savings and reduced greenhouse gas emissions resulting in the use of 95% of methane generated.
  • Solids content in biosolids being sent for land application has increased from 18% to 20%, resulting in better quality product and lower transportation and energy costs.
                           EMS certified by the national biosolids partnership

The National Biosolids Partnership is a not-for-profit alliance formed in 1997 with the National Association of Clean Water Agencies, Water Environment Federation, and U.S. Environmental Protection Agency. Its goal is to advance environmentally sound and accepted biosolids management practices. Biosolids producers, service contractors, and users—together with regulatory agencies, universities, farmers, and environmental organizations—have input into shaping NBP priorities through scientific and technical support relating to biosolids issues.

The type of system in place in Mankato is a bright indicator of the future of biosolids. In fact, Mankato City Manager Pat Hentges noted, “Who knows, in the future it might be a closed system,” where wastewater could be cleaned and reused as drinking water.

For more information about clean, environmentally efficient biosolids processing, contact Schwing-Bioset

Tags: Biosolids Processing, Water Environment Federation (WEF), Biosolids, Wastewater Treatment