| The emission of hydrogen sulfide to sewer atmosphere implies noxious odor, deterioration of concrete sewer by corrosion and health endangerment to both sanitation and wastewater workers. Several solutions to this problem exist but alternatives are always being researched to identify a solution that effectively performs odor control, prevent concrete sewer corrosion without endangering the downstream biological wastewater treatment by increasing its load and of course, cost effective.;Accell, a non hazardous, protein surfactant complex made by Advanced Biocatalytics Corporation, Irvine California, claims to satisfy the aforementioned criteria while also significantly reducing the fats, oil and grease (FOG) content of wastewater which as well contributes to the odor problem.;To test for the effectiveness of the surfactant product at providing a solution to the problem on a microbial level, full scale experiments were conducted on DC Water sanitary sewer system. Controlled dosing of Accell was done in a 10 feet by 9 feet East Outfall Sewer with a flow capacity of 140 MGD while the impact on FOG, sulfide, dissolved oxygen, pH, oxidation reduction potential, total suspended solids (TSS), volatile suspended solids (VSS), nitrate, phosphate and nitrate level was monitored for a period of 12 weeks.;Although dissolved oxygen level remained low during the summer weeks of research, results showed a steady decline in TSS and VSS levels close to 74% from baseline studies accompanied by nitrate and phosphate concentration reductions. Hydrogen sulfide concentration stayed at a concentration below 3ppm at the two closest sites to the dosing point. Our attempt at researching the product's effect on other water quality is inconclusive at this stage and further investigation is still required to substantiate Accell claim for FOG reduction in collection system. |
