Kolmetz.com Cooling Tower Monitoring 10 Page 11
engineers of the cooling towers sometime have to install a high performance mist eliminator to
reduce the drift loss as low as 0.0005%. This increases the cost and operating horsepower of the
cooling tower to reduce the potential future environmental impacts.
Organic Loading of the Cooling Water: Organic loading of the cooling water can be determined
by a number of tests of the cooling water, including total HAP, total VOC, speciated HAP, total
organic compound (TOC), or chemical oxygen demand (COD). These tests will identify the
total organic loading or the specific chemical loading of the cooling water. As a result of the
operation of the cooling tower, many of these organic compounds will be volatilized and emitted
to the atmosphere.
Lower Explosive Limit (LEL) Monitoring: LEL monitors can be placed in the vicinity of the
cooling tower, to monitor the cooling tower for episodic releases of combustible organic
compounds. The LEL monitors would provide near real-time indication of a release from the
cooling tower.
Material Balance: A material balance of a facility's operation can also be utilized as an indicator
of large on-going releases, or large episodic releases. The material balance could indicate a
significant loss in the facility, which may be a result of cooling tower emissions. The material
balance method could only be utilized for large losses, due to the inefficiency of the balance.
7.
Future Possible Regulations
The evolution of environmental regulation indicates that monitoring cooling tower performance
will be enhanced in the future. This will be facilitated by the development of new technology.
Three of these technologies are identified below, and are currently being implemented at sites in
the United States. Although not specific cooling tower monitoring schemes, these technologies
may assist in the monitoring of cooling tower performance in the future.
Open Path FTIR Monitoring: Open Path Monitoring utilizing a Fourier Transform Infrared
(FTIR) technology can provide real time ambient air monitoring along an open-air path (or fence
line). The open path FTIR transmits infrared (IR) light along the monitoring path to a retro-
reflector mirror, which returns the IR beam back to the FTIR. Gaseous compounds present in the
beam absorb IR energy at characteristic wavelengths. The amount of energy absorbed is directly
proportional to the concentration of the gas. The use of this system would establish a path or
fence line monitoring system, which would provide an indicator of the cooling towers
performance to monitor and detect releases and emissions to the atmosphere.
Open Path UV Monitoring: Open Path Monitoring utilizing a ultraviolet (UV) technology can
provide real time ambient air monitoring along an open-air path (or fence line). The open path
UV transmits ultraviolet light along the monitoring path to a retro-reflector mirror, which returns
the UV beam back to the monitor. Gaseous compounds present in the beam absorb UV energy at
characteristic wavelengths. The amount of energy absorbed is directly proportional to the
concentration of the gas. The use of this system would establish a path or fence line monitoring
