BioCycle January 2006, Vol. 47, No. 1, p. 24
Treated water is in high demand in places that range from breweries in Boonville to mountain villages in New Mexico and reuse programs in King County, Washington.
THROUGHOUT THE NATION – and the world – the critical need for water is leading to greater reuse of treated water. Coming issues of BioCycle will report on these developments, providing additional data on places like Cloudcroft, New Mexico where the state’s governor Bill Richardson stressed that “water reuse is essential.” This summer, the village of Cloudcroft with its 1,000 population at an elevation of 9,000 feet will install a water recycling system that includes a membrane bioreactor and reverse osmosis with ultrafiltration technology.
The village economy relies heavily on tourism with a ski hill, golf course and many summer events. Currently, the village has to truck water to satisfy requirements during peak demands.
The new wastewater system will utilize the ITT/Sanitaire Dual Stage membrane bioreactor (MBR) to supplement the irrigation water demand and the potable water supply. According to John Koch of ITT/Sanitaire based in Brown Deer, Wisconsin, the MBR provides a high degree of treatment, combining activated sludge for organic and nutrient removal with membrane filtration for liquid solids separation. In addition to the MBR, an ITT/Aquious reverse osmosis (RO) system was designed to follow the MBR process – providing further treatment to the effluent. The current raw water storage reservoir collects and retains the village’s water source.
The addition of the integrated membrane system will enable the village to supplement the current raw water sources with highly treated wastewater effluent.
“Our bathtub is not very big, and we’re still in a period of drought,” explains village administrator Mike Nivison.”We use about 66 million gallons/year of water and need to put back close to 90 percent. Water reuse in Cloudcroft is part of our infrastructure as we create a pond to store water.”
RECLAIMED WATER IN KING COUNTY, WASHINGTON
The Wastewater Treatment Division in King County, Washington has been safely using reclaimed water since 1997 at its regional treatment plants in Seattle and Renton. The reclaimed water meets Class A standards of the state departments of Health and Ecology. Both facilities reuse treated wastewater for irrigation, tank cleaning, etc. replacing drinkable water (about 4 to 5 million gallons/ month). The water from the Renton plant – about 1.3 million gallons – is distributed off-site during the hotter months of July and August. About half is used to irrigate ball fields and the other half goes to a wetlands nursery.
Treatment alternatives include ballasted flocculation that uses minute particles to hold materials together. Larger, heavier particles settle out of the wastewater rapidly, improving removal of solids and organic material. Wastewater then flows to another machine “through lots of fuzzy pink balls that pick up most of the solid particles … reducing the footprint of the primary treatment process.”
As part of other treatments, biological aerated filtration injects air and granules which separate solids and provide a surface for biological activity to take place. This technology can be adapted to remove nitrogen. A membrane bioreactor combines an activated sludge secondary treatment bioreactor and microfiltration membrane. For more details about King County’s Water Reuse program, contact Jo Sullivan at (206) 296-8361 or via e-mail: dnr.metrokc.gov.
WASTEWATER RECYCLING PLANT
Penn State University began experiments with treated wastewater in the 1960s, and by the mid-1980s had developed a delivery system. Researchers in the silviculture department have tested different tree species that benefited from higher nutrients of nitrogen and phosphorus. According to Prof. Todd Bowersox, by replacing typical forest community of red oak, black oak, red maple and hickory – trees adapted to normal rainfall and acidic soils – with thirstier species found along state riverbanks like sycamore, silver maple, green ash, river birch, black gum and Norway spruce, a natural demand was created for wastewater. They also found that native species such as quaking aspen did well.
Most important, declared Bowersox, the water is returned “to the ground from which it came. … This is really a wastewater recycling plant. The real goal is to discharge this water in a way that’s environmentally friendly, and putting it back into the ground.”
Robert Bastian of the EPA Office of Wastewater Management in Washington, D.C. has written extensively about the future of water reuse. He has reviewed scientific papers that have covered: Chemical and microbial comparisons of reclaimed water; Epidemiological studies of populations consuming reclaimed water; and Multiyear animal testing for potential carcinogenic, terratogenic, and mutagenic effects. Sums up Bastian:
“Such studies generally have shown that reclaimed water can produce high quality food and its quality is as good as that of existing local raw water supplies … Improved technologies for small-scale on-site water reclamation and reuse, ranging from greywater recycling systems to membrane reactors, probably will become important.”
WASTEWATER RECLAMATION AT ANDERSON VALLEY BREWING POND
From Peter Suddeth at the Anderson Valley Brewing Company in Boonville, California comes this report on its wastewater reclamation methods:
“First off, we try to use as much water as we can multiple times before it becomes waste,” begins Suddeth. Cold water is run through the heat exchanger to cool down the boiling wort (liquid that will be fermented into beer) to a temperature suitable for fermentation; water goes in cold, beer goes in hot – beer comes out cold, water comes out hot. This hot water is used for cleaning, and future mashing (the stewing of the grains to extract flavor, sugar, and enzymes). Caustic wash water from the tank and filler machine’s cleaning cycles can be used during scrubbing of the floors.
Once it becomes waste, the water runs through a course and medium screen to filter off larger solids, then is pumped to a settling tank where smaller solids settle out and are removed. The water goes through a three-pond treatment system, in which the ponds are aerated and/or stirred. Overflow from one pond is fed into the successive pond. At each step, biological and enzymatic processes break down the wastes, producing methane at first, and oxygen eventually. By pond three, the water supports frogs, fish, water beetles, algae, etc. “A white egret and its mate have been seen hunting in pond three. From pond three, water is used for irrigation of pastures for our Shire Horses and pygmy goats,” adds Suddeth.
Other BioCycle worthy practices, Suddeth continues, include the following: Spent grain and hops are used by local ranchers as feed supplement for livestock including cattle, sheep, and pigs; Glass, plastic, and cardboard are all recycled through a company called Summertime Farms. Old equipment, stainless steel, PVC piping, copper tubing, etc. are stored for reuse in future projects. “As one of the largest industrial employers in Anderson Valley, we still produce only one 4′ by 4′ by 8′ dumpster (or less) of refuse per week.”
“We’ve almost completed our $860,000 state-of-the-art photovoltaic project, Two arrays; a freestanding array of 176 panels, and a 592 panel array on the facility’s roof. When complete, the project will be the largest private photovoltaic solar array north of the San Francisco Bay Area, and should supply up to a third of our annual electrical needs.”
On its website (www.avbc.com), the company describes itself as a regional brewery dedicated to the art of brewing and protecting our environment – reusing or recycling much of its waste products and providing spent grain to local farmers for feed and fertilizer. It has installed its own wastewater treatment facility and uses the reclaimed water to irrigate its 30-acre property. In the last year, the brewery has diverted 2,000 tons of spent grain and over 30 tons of recycled glass, cardboard and plastics. Savings from the wastewater treatment facility and the solar array are figured to be at least $80,000 annually.
Its award-winning Boonville Beers (in scenic Mendocino County) have won the company honors as a Top Ten Brewery.
January 30, 2006 | General
Sustainable Water Supplies With Wastewater Recycling
BioCycle January 2006, Vol. 47, No. 1, p. 24