Concord, New Hampshire
Electrical-grid powered aeration is used to mix and oxygenate wastewater in most treatment
plants. However, much more mixing than oxygenation typically is needed. This imbalance
creates an operational inefficiency that increases costs and greenhouse gas emissions. The New
Hampshire Department of Environmental Services directed a 3-site study to assess the ability of
solar powered circulation (SPC) to reduce or eliminate the need for aeration. Water quality, odor
event, sludge buildup and power consumption data were collected 1-year pre-SPC and 1.25-years
during-SPC. The results generally indicated no differences between study periods in effluent
flow rates, total suspended solids, biochemical oxygen demand, dissolved oxygen, pH, ammonia
or nitrate levels. No discharge violations or odor events, and little or no sludge buildup, occurred
during SPC. Power consumption declined by 43-91%, and payback periods were 1.5-3.9 years.
These data and a 25-year, low maintenance, SPC-unit life expectancy indicated a long-term
improvement in operational efficiency.
Posted: May 20th, 2011 | Filed under: 100K-500K, 50k-100k, Stormwater, Waste Water Treatment, Water Treatment | Tags: Cost Savings, Energy Savings, Environmental Impact, Green Infrastructure, Improved Effluent Quality, Improved Oxygenation Efficiency, Improved Wastewater Mixing, Innovative Mixing Design, Operational Costs Declined, Reduced Carbon Footprint, Reduced Greenhouse Gas Emissions, Solar Power | No Comments »