Hydrogen Sulfide (H₂S) gas and Sulfuric Acid (H₂SO₄) are the two materials excogitated from the Sulfur-containing materials inside the wastewater and contaminated stormwater in sewer and drainage system respectively by Sulfur reducing and oxidizing bacteria. In Hong Kong, due to insufficient land space, some of the drainage and sewer system are build nearby the community and the presence of the odorous gas could promote immense sensory botheration to the surrounding neighbourhood. Sulfuric acid, on the other hand, would corrode the water pipe that was constructed using the alkaline concrete. This study is to scrutinize a sustainable and long-lasting solution to address both odor and corrosion controversies inside the drainage and sewer system. The contemplated approach is by ut...[ Read more ]

Hydrogen Sulfide (H₂S) gas and Sulfuric Acid (H₂SO₄) are the two materials excogitated from the Sulfur-containing materials inside the wastewater and contaminated stormwater in sewer and drainage system respectively by Sulfur reducing and oxidizing bacteria. In Hong Kong, due to insufficient land space, some of the drainage and sewer system are build nearby the community and the presence of the odorous gas could promote immense sensory botheration to the surrounding neighbourhood. Sulfuric acid, on the other hand, would corrode the water pipe that was constructed using the alkaline concrete. This study is to scrutinize a sustainable and long-lasting solution to address both odor and corrosion controversies inside the drainage and sewer system. The contemplated approach is by utilization of hydrogel technology with the incorporation of metabolic inhibitors to suppress the total bacteria population and epoxy coating to protect the concrete façade from the corrosive Sulfuric Acid.

Both laboratory study and field study in Jordan Valley drainage system using 400 grams of hydrogel indicated that the total bacteria population was curtailed for 90% and 80% respectively. Hydrogen Sulfide gas level was also discounted by 90% during the whole year monitoring in the drainage system. Corrosion study in the drainage system also showcased that the hydrogel was capable to retain the structural rigidity of the concrete coupon by approximately 10% than that in the system without hydrogel. Electron images from the concrete surface also indicated fewer blemishes and pores on the concrete surface in the system with hydrogel presence. On the other hand, the epoxy coating was proven to be able to retain the whole concrete mass, structural rigidity and overall concrete composition after 90 days deployment in the drainage system.