Wastewater Facility
I just wanted to let you know how pleased I am with the Bio-Tabs for reducing Hydrogen Sulfide from our forced main entering the East Providence Wastewater Treatment Facility.
The Town of Barrington recently experienced a collapsed forced main at the end of the 3.5 mile 24 inch diameter pipe. The collapse was due to sulfide corrosion. Measured levels were reported between 200-400+ ppm in atmospheric samples.
To reduce H2S levels and prevent future problems it was decided to treat for H2S removal at 2 of the 3 pump stations discharging into this forced main. The 2 stations chosen were the Bay Spring Station which is closest to end of pipe at 2 miles and the Brickyard Station which is furthest from the end of pipe at 3.5 miles.
Barrington investigated various systems to reduce H2S those being Bioxide, Bacta-Pur, Potassium Permanganate in liquid form plus the new solid form sticks (CR) Control Release extruded potassium permanganate and Cellinite Bio-Tabs.
As the pump stations are in residential areas and homes are within 100 feet from the stations, Barrington took into consideration vandalism, security, aesthetics, noise, power and water consumption, equipment, chemical costs, construction and product delivery.
These considerations eliminated all but Potassium Permanganate CR and Cellinite BioTabs. Both products are in solid form and do not require power, carry water, construction, dispensing equipment etc... Barrington tried both products with success. The Potassium Permanganate CR is placed in a netted bag and submerges into the wet well. The Bio-tabs are just tossed into the wet well. The following log shows when and how much each product was used, the daily flow rates and atmospheric H2S readings taken at end of pipe. You will also notice that flow rates also affect H2S readings. As the flows increase, the H2S decreases. This allowed us to easily adjust daily dosing of the Bio-Tabs and control chemical costs.
Annual chemical costs were estimated to be Permanganate at $31,000 and Bio-tabs at $20,000.
As both products proved near equal in effectiveness the Bio-Tabs were chosen, not only for cost but also ease of handling. The Bio-tabs are clean solid disc requiring only gloves for handling. Any broken pieces can be simply swept into to wet well. The Potassium Permanganate CR, although solid, requires proper dust masks, eye protection and gloves. When broken the Permanganate will leave a dust that is hazardous and when moist will stain anything it comes in contact with. This will require special cleaning products.
We are presently testing the Bio-tabs at another pump station for its effectiveness in grease reduction in the wet well. In just 2 weeks the operators have noticed the grease layer looking a bit softer. This trial will continue. If successful the Bio-tabs will be our choice for grease control.
We are very pleased with the Bio-Tabs. I must say, being in the wastewater business for 28 years I have seen and tried many products that promised to be the -solution for my problems. When I heard how simple the Bio-tabs were I thought this was another product with false hopes. I cannot tell you how pleased I am that the [Cellinite] BioTabs are all you said they were.
I wish you great success with this product. If needed, I will be glad to discuss our success with any potential customer of yours.
- Tony Silva, Dept. of Public Works, Town of Barrington
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