In-Situ Shipboard Heat Exchanger Cleaning and Maintenance Using Innovative i2 Bubble Infusion (i2BI) Technology
WP-201219
Objective
Ship board heat exchangers (HX) are used to cool both water and other fluids. Ranging in size from 5 to 5,500 gallons, ship board use can include; central freshwater, main engine and stern lube oil cooling and jacket water cooling and any exchanger malfunction can hinder ship use. Fouling by biological or mineral contaminants including; sedimentary components, metal oxides, minerals, and biological/microbiological is the principle cause of malfunction.
The objective of this project is to demonstrate and validate (DEMVAL) the use of i2 Bubble Infusion (i2BI) technology to reduce both the time required to clean a fouled HX and the rate of fouling within an operational exchanger. It will demonstrate the ease of i2BI system integration on to an existing system without extensive HX modification and the economic benefits of reduced fouling and cleaning frequency. The operating data gathered during this project will allow for the transition of this innovative i2BI technology into routine use.
Technology Description
The core technology is an innovative and patented iodine infusion method (US Patent# 7,329,385) that reduces microbial counts within a fluid, an air stream, and vessel using iodine vapor infusion. It has been proven in independent studies to inactivate waterborne and surface microbes and may disrupt microbial adhesion preventing or retarding biofouling in plate HXs. The microbes chosen for testing were active biofilm producers, pseudomonas a being the most active. i2BI technology utilizes the effectiveness of iodine disinfection but without high level biocide use, residue, or long dwell time. Unlike current iodine resin fluid disinfection, water does not enter the i2 cartridge so there is no concern for fouling of the resin bed. Additionally, the i2 resin is unaffected by water pH and turbidity. Compressed air is directed through a cartridge containing iodinated resin beads where iodine vapor is eluted into the airstream. Air containing iodine vapor is imparted into a fluid as a perfusion of bubbles. The interaction between the iodinated bubble and microbes is what accounts for the rapid inactivation.
There are two parts to the technology - the i2 cleaning protocol (i2CP) and the i2 maintenance protocol (i2MP) that uses the i2 bubble infusion process. The i2CP is a cleaning method that uses iodinated air and eco-safe cleaners as part of an in situ method to eliminate existing foul within HXs. The i2CP method eliminates the need to break down the exchanger. Although cleaning-in-place methods have been developed, they merely recirculate the cleaner throughout the exchanger requiring considerable exposure time. The i2MP method uses a timed infusion of iodinated air bubbles into the water stream entering a HX to prevent or reduce foul formation. It does not require system disassembly and, unlike current methodology, treats HX systems chronically rather than acutely.
Benefits
The Department of Defense (DoD) wide savings resulting from the reduced frequency of small to medium HX cleaning and maintenance are estimated to be $10 million per year. To reduce the cleaning and maintenance frequency of the HXs will also result into additional DoD-wide benefits such as savings of wastewater disposal costs of $1 million/year. Improved system function from reduced fouling will lower energy consumption (approximately one billion kWh/year) and associated greenhouse gas production, which amounts to about 500,000 metric tons/year. (Anticipated Project Completion - 2014)
Points of Contact
Principal Investigator
Mr. Bruce Holden
NAVFAC Engineering Service Center
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.
