Monday, December 21, 2009

Non Chemical Water Treatment Device


I recently had the opportunity to see the conversion of a cooling tower from standard chemical water treatment to a new "Non Chemical Water Treatment Device". In this instance the unit installed was called a Fluidtron. These pictures were taken at about 90 days into the non chemical water treatment program. While the algae build up is troubling it is a minor problem compared to the aggressive corrosion cells that developed. The customer ended up re-coating the tower basin with an epoxy and installed brominators to add Bromine to control the algae.
A quick search of vendors selling this product uncovered some marketing literature. One brochure stated that the unit "eliminates the need for chemical treatment" and listed the benefit of "extended life of equipment" because "reduced corrosion rates extend equipment life". Certainly one case study does not reveal enough data to draw a conclusion, however, in my opinion the results achieved here border on negligence.
I am not implying that all non chemical water treatment devices do not work but the end user should to do their homework before making an investment in a "new" system that is designed to protect the heart of a buildings HVAC system.

Tuesday, December 8, 2009

Cooling Tower Frozen Over


A unexpected cold snap hit recently and created some problems for this cooling tower. It was was not drained and froze over. It is not apparent whether or not there was any damage to the tower or the fill. For towers that are operated in climates that may experience freezing temperatures be sure that the sumps are drained or that the sump heaters are on and operating correctly when the temperature begins to drop.

Thursday, December 3, 2009

Non Oxidizing Microbiocide


Non Oxidizing Microbiocides (NOM) have a specific mode of operation. Some attack structural, or functional components of protoplasm such as enzymes, proteins, lipids, metals, or minerals. Some NOM poison or interfere with the normal metabolic process. Still others inhibit the permeability of the cell membrane. All of these modes contribute to the death of the cell body.
Regardless of the the mode, all NOM have the same general effects upon the system.
1. In the presence of a toxic substance mircorbiological organisms increase their rate of metabolism. This is part of their nartural survival response. This means that underfeeding a biocide will actually stimulate the microbiological growth in the system.
2. The microbiological population in a cooling tower can be drastically altered through the use of only one NOM. Species and strains of microbiological organisms least affected by the biocide will some become the dominant strain in the system.
3. NOM kill, but they do not consume the organic molecules that previously supported the life of microbes. The debris of the dead cells provides a significant source of food for new growth. This tends to cause a response of higher growth and reproduction rates. This is one of the main reasons an oxidizer is often used in conjunction with NOM. Oxidizers physically destroy the organics eliminating the food source.
4. Microbiological organisms rapidly adapt to a changing environment. The organisms will develop resistant strains.