Biofilter absorbs gases

Problem

The Karcher Creek Wastewater Treatment Plant in Port Orchard, Wash., needed to control odors and had no room to expand.

 

Solution

Engineers chose a biofilter system from Bohn Biofilter Corp. that treats 200 ppm hydrogen sulfide. The biofilter, built on the roof of the solids storage tank, accommodates large mixers penetrating through the roof into the tank below.

 

Result

The system provides odor control and was shut down only once in seven years for fan maintenance. 520/624-4644; www.bohnbiofilter.com.

 

Insulated cover seals in odors

Problem

Odors from the Southwest Water Reclamation Facility in Bradenton, Fla., bothered golfers on a nearby course and local residents.

 

Solution

The Manatee County Public Works Department selected the LemTec modular insulated cover from Lemna Technologies to cap the 244-foot circular equalization tank. Individual casings of 1-inch closed-cell insulation sealed between two sheets of 40 mil HDPE geomembrane minimizes odors while adjusting to fluctuating water levels.

 

Result

The product proved cost-effective and maintenance-free. 612/253-2000; www.lemnatechnologies.com.

 

Ozone chamber controls odors

Problem

Engineers at the 333 mgd North Side Water Reclamation Plant in Skokie, Ill., proposed ozone to reduce odor complaints.

 

Solution

They chose an odor control system with corrosion-resistant fiberglass contact chamber from Ozonology. The chamber, sized for the exhaust air volume, detains hydrogen sulfide for 30 seconds, in which time it reacts with ozone and controls odor. A monitor regulates ozone production to match odor loads.

 

Result

The system has controlled odors for six years. 866/998-8808; www.ozonology.com.

 

Oxidation technology controls odor

Problem

For 20 years, hydrogen sulfide odor from 8.5 miles of sewer made life unpleasant for neighborhoods and small businesses in Clarksville, Ind. Wastewater Treatment Department personnel struggled to find a cost-effective solution.

 

Solution

A Source Technologies representative recommended the VSP superoxide process. It combines the VSP catalyst, a complex organic compound, with oxygen generated on site using a molecular sieve and the two chemistries combine to oxidize the sulfide in the water within minutes, preventing the formation of hydrogen sulfide in the lines.

 

Result

Since its installation in February 2010, the area has been odor free. Clarksville town council president Greg Isgrigg received the 2010 Collection Systems Small Facility Award from the Indiana Water Environment Association for solving the problem. 859/223-1444; www.sourcetechnologiesllc.com.

 

Activated carbon ensures fresh air

Problem

A 30 mgd municipal wastewater treatment facility in a Connecticut neighborhood wanted to minimize odor breakthrough while reducing activated carbon changeout frequency to lower costs.

 

Solution

Operators chose DARCO H2S, a nonhazardous lignite-based activated carbon from NORIT. The product’s natural catalytic capabilities required no impregnation to achieve optimal porosity and maximum hydrogen sulfide absorption.

 

Result

The facility extended its carbon filter bed life from four to more than 18 months, and the initial fill was still usable. Over five years, operators eliminated more than 12 changeouts, saved more than $360,000, and reduced odor-testing expenses by nearly 50 percent. 800/641-9245; www.norit-americas.com.

 

System stops odors, reduces FOG

Problem

Residents complained of sewer odors in neighborhoods near the Howell Avenue pump station in Riverhead, N.Y. The two wet wells also had large amounts of fats, oils, and grease.

 

Solution

Parkson Corp. proposed an OHxyPhogg V80 system with one standard nozzle per wet well. The Sewer District installed it in July 2011.

 

Result

Odor complaints ceased and FOG was reduced despite additional grease being diverted from other pump stations. Operators found the system easy to operate and maintenance requirements minimal. 888/727-5766; www.parkson.com.

 

Device controls odor and corrosion

Problem

A southern Arizona municipality had a two-mile force main with hydrogen sulfide peaking at 3,400 ppm and averaging 340 ppm at its outfall. Daily temperatures reached 110 degrees F.

 

Solution

Operators installed the FORSe 5 odor and corrosion control system from Anue Water Technologies in the line at the wet well and downstream from the check valve. The device diverts a fractional flow, infuses it with oxygen and ozone, then returns it to the force main.

 

Result

Five days after installing the device, hydrogen sulfide levels dropped from 17 mg/L to less than 0.2 mg/L. Vapor measurements decreased from greater than 3,400 ppm to less than 10 ppm. 760/476-9090; www.anuewater.com.