Indoor premise plumbing (PP) is the last part of the water distribution system that influences the water quality before the treated drinking water reaches customers at their taps. The PP pipelines have smaller diameters than those in other parts of the distribution systems, resulting in significantly higher loss of residual disinfectant and higher biomass growth. Depending on building design and customers’ usage, water in PP could stay unused for days, leading to quality deterioration through the reactions between disinfectants with the biofilms and the pipe materials. Diminishing concentrations of disinfectants throughout the distribution system and especially in PP eliminate the safeguard against pathogen exposure for customers at their taps. To overcome the challenge of maintaining water quality at the taps for end-users, we developed microplasma jet array technology to remove biofilms grown on PVC surfaces. Three-dimensional reconstruction of the biofilm images obtained by optical coherence tomography revealed a porosity of 32% ± 5% and 10% ± 2% with pores in 50 µm × 50 µm × 80 µm and 10 µm × 10 µm × 5 µm for biofilms grown from groundwater amended with silicate and tin biofilms, respectively. Faster disruption rate by microplasma jet treatment for silicate biofilms was observed compared to that for tin biofilm (16 ± 2 µm/min vs. 9 ± 2 µm/min). Analysis of confocal laser scanning images of biofilms showed that both the cells and the extraccelular polymeric substances were removed. These results revealed that the novel microplasma jet array provides a potential solution for controlling biofilms in premise plumbing and the physical structures of these biofilms played an important role on the disruption efficacy of microplasma jet treatment for drinking water biofilms.

Roles of corrosion inhibitors on simulated drinking water biofilm physical structures and responses to microplasma jet array treatment

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.