87-15: The Growth and Control of Nitrifying Bacteria in a Urea Plant Cooling History of Cooling Towers

87-15: The Growth and Control of Nitrifying Bacteria in a Urea Plant Cooling History of Cooling TowersA urea plant cooling water system experienced problems with the growth of nitrifying bacteria which produced nitric acid from ammonia resulting in a sharp drop in the pH of the cooling water was found to drop from 7. 5 to 6. 1 over a period of 34 days. It was demonstrated in the laboratory that bacteria possessing the enzyme urease were present in the cooling water. A number of biocides were screened for their ability to inhibit growth of ammonia

through the high end of the expected temperature range in hot water heaters and dishwashers

Occasionally

one-drum liquid solution that combines 5-Chloro-2-Methyl-4-Isothiazolin-3-one

The paper will discuss recent innovations in solid biocides and the numerous advantages over their liquid counterparts

conducted by qualified personnel

An ion exchange based technology has been developed to selectively remove calcium from aqueous streams effectively eliminating calcium as the limiting constituent for COC

This Standard covers the design

at significantly lower system ORP

The root caused investigation indicated serious corrosion problems with fan equipment

the principles apply well to industrial plants and to other water treatment systems

all the droplets are included in the statistical sampling

while the supplies of uncontaminated water dwindle