Grantee Research Project Results

Final Report: Surface plasma-based decontamination for pathogen removal from water pipes

EPA Contract Number: EPD15038
Title: Surface plasma-based decontamination for pathogen removal from water pipes
Investigators: Maneval, David
Small Business: SurfPlasma Inc.
EPA Contact: Richards, April
Phase: I
Project Period: September 1, 2015 through February 29, 2016
Project Amount: $99,798
RFA: Small Business Innovation Research (SBIR) - Phase I (2015) RFA Text |  Recipients Lists
Research Category: SBIR - Homeland Security , Small Business Innovation Research (SBIR)

Description:

Americans depend on safe uncontaminated water that flows through pipes from public water-supplies. A problem with water pipes is biofilm formation, natural microbial communities that form on the inner pipe surfaces. Biofilms can impede flow and make water discolored, bad tasting or foul smelling. However, more importantly, biofilms may harbor and release human pathogens including the agent of Legionnaire’s disease. Current best practices for decontamination are often ineffective, expensive, and environmentally unsound. SurfPlasma proposed a novel innovative core technology, Surface Plasma-based decontamination (SBD) to be employed in frequent cycles to destroy biofilms and ensure water pipes remain pathogen-free.

The research project proposal examined the feasibility of dielectric barrier discharge atmospheric surface plasma to disrupt and decontaminate microbial biofilms, including Legionella pneumophila, in water pipes. Phase I of the proposal addressed these technical research goals:

1. Design and fabricate a prototype, electrode-embedded water pipe,
2. Generate surface plasma on the inner surface of such a pipe, and
3. Demonstrate effective biofilm decontamination by SBD.

Summary/Accomplishments (Outputs/Outcomes):

SurfPlasma evaluated dielectric substrates for suitability in this dielectric barrier discharge plasma application, and successfully designed, constructed, tested and optimized requisite electrical components, assemblies and parameters. A prototype, plasma electrode-embedded pipe was fabricated and has been successfully demonstrated to generate surface plasma on the inner surface of such pipe. Experiments established that at appropriate low voltage input power, SBD effectively killed all organisms in the biofilms tested, including target organism Legionella pneumophila, within biofilms in less than 2 minutes when exposed to such surface plasma.

Conclusions:

SurfPlasma developed the Proof-of-Concept prototype, electrode-embedded pipe to generate surface plasma for decontamination of biofilms as envisioned at the project’s inception, namely by:

• Demonstration of plasma electrode killing of biofilm microbes on various flexible dielectric materials
• Delineation of power levels and lethal exposure times with select biofilm organisms including Legionella
• Definition of requisite operational parameters: input voltage, frequency, power and plasma energy flux
• Establishment of kinetics and extent of SBD disinfection for biofilm organisms on various dielectric substrates
• Successful design and fabrication of a market feasible prototype pipe with embedded electrodes
• Generation of preliminary data on parameters for complete biofilm inactivation on the inner surface of a prototype water pipe

Conventional Disinfection Methods

• Produce potentially toxic levels of chlorine and chlorinated compounds necessitating transport and disposal
• Can employ copper, silver, or other agents that may similarly generate environmentally harmful waste
• Can require substantial energy input to flush pipes using high velocities or heat or abrasives
• Can damage or corrode pipes, requiring premature replacement

Surface Plasma-based Decontamination

• Environmentally friendly: plasma generation produces no long term residual toxic materials, employing only ionized air
• Performed at atmospheric pressure and low temperatures with reduced safety and energy concerns
• Energy efficient (uses less power than a light bulb) reducing environmental impacts from power generation
• Generally does not corrode pipes or other environmental surfaces
• Surface Plasma-based Decontamination = Green Clean Technology

Based on these results, SurfPlasma successfully demonstrated and proved the Technical Feasibility of effective biofilm decontamination by SBD.

Commercialization:

SurfPlasma received interest from a large plastic pipe manufacturer to discuss future development activities. SurfPlasma also received a Letter of Support from a potential corporate partner interested in developing new prototypes in Phase II and commercial products in Phase III.

Journal Articles:

No journal articles submitted with this report: View all 1 publications for this project