Bulletin 5008
Ammoniator Materials/Installation Notes

Chemical Injection Technologies
Technical Bulletin
SUPERIOR™ Gas Ammoniators
Applications, Materials and Installation Notes
APPLICATIONDESIGN

Chloramines are the result of the reaction ofammonia and chlorine in water. They are widely usedin potable water treatment as an inexpensivealternative to using activated carbon filtration fortrihalomethane precursor removal, and to maintainchlorine residuals for an extended period.

SUPERIOR™ Gas Ammoniators are identical indesign and function to SUPERIOR™ Gas
Chlorinators. All features, advantages, dimensions
and specifications contained in SUPERIOR™ Gas
Chlorinator literature, with the exception of ejector
nozzle requirements and part numbers, may beinterchanged for use with SUPERIOR™ Gas
Sulfonators.

The reaction of chlorine with ammonia produces
monochloramine, dichloramine, and trichloramine.
Monochloramine is the most commonly used form ofchloramine since it contributes little or nothing totaste and odor in the finished product. To produce
monochloramine, the chlorine-ammonia ratio must
be maintained at 3 to 4 parts chlorine to one partammonia. When chlorine is added in excess of thisratio, coupled with a lower pH, it can produce
dichloramine and trichloramine. These two
chloramine forms can cause taste and odor
problems in the drinking water. Trihalomethanes
which have been formed prior to the addition ofchloramine will not be altered in this process. Any
free chlorine present prior to the application ofammonia will form chloramines.
Chloramines are more widely known as “combinedchlorine”. They do not react with precursors to form
trihalomethanes. Trihalomethanes are suspectedcarcinogens and are formed in the presence of freechlorine residual when the precursors are present
and sufficient contact time is available. It should be
noted that there is an ongoing debate about therelevance of the studies and methodology used in
the research on trihalomethane toxicity.
Of the two types of chlorine residual, combined
residual is a far less active disinfectant than freeresidual. Therefore, either the dosage of combined
residual must be higher than that of free residual, or
the contact time longer to produce equivalent results.
This combination of dosage and time is referred to as
Ct value. Ct values for chloramines are an order ofmagnitude larger than free chlorine.

NH3 Materials/Installation

MATERIALS
Ammonia (NH3) in a dry (anhydrous), gaseous stateis relatively compatible with a number of common
engineering plastics. Unlike Chlorine gas, Ammonia
exhibits no corrosive effects on stainless steel,although in a pressurized state its highly alkaline
nature can cause some plastics to swell and discolor.
Therefore, the PVDF inlet adaptor used in gas
chlorinators is replaced with a stainless steel adapter
designed to fit the slightly different dimensions of theammonia cylinder valve. Also, the silver inlet valve
plug is replaced with an identical valve plug made ofstainless steel.
The special Viton O-Rings used in SUPERIOR™ Gas
Chlorinators and Sulfonators are designed towithstand highly acidic environments and are notsuitable for use in Ammonia gas. All O-Rings inSUPERIOR™ Gas Ammoniators are made ofneoprene. All other materials, not specificallymentioned above, are the same as those used inSUPERIOR™ Gas Chlorinators.

INSTALLATION CONSIDERATIONS
Ammonia must be added to the system before thechlorine. Since the ammonia must come into contactwith the chlorine to form the chloramines, staticmixers should be installed in the piping before theapplication of chlorine in order to disperse theammonia. Another static mixer should be installed
after the addition of the chlorine to thoroughly mix
the chlorine/ammonia solution.

Copyright © 1997, Chemical Injection Technologies, Inc., Pub.No. 1297-1

Printed in U.S.A.

Other mixing methods may be employed, depending
upon the installation. For example, excellent mixing
can be provided by placing a static mixer between
the application points of ammonia and chlorine,
when both of those points are in a pump suction line.

HARD WATER CONSIDERATIONS
Users should be aware that there exists a problem
when an Ammoniator is installed in a water system
where the ejector supply water is considered “hard”.
Hard water is high in calcium salts. This causes areaction with the ammonia gas that causes themineral to precipitate out of the water and deposit on
the walls of the nozzle. These deposits can form
rather quickly in severe “hard” water conditions, andwill eventually cause the ejector to stop producing
vacuum. The only cure at that point is to remove thenozzle and clean it in muriatic acid.
The question has arisen with regard to “What isHARD water?”. Generally, water is considered ideal
at approximately 120 PPM (7 GRAINS) hardness
content. That’s ideal for people and washing clothes,
not necessarily for ammoniator ejectors. At 120
PPM (7 GRAINS) there will definitely be some
deposits formingin the nozzle, but it will not be serious and probably
will not plug things up within the first 3 or 4 months,
possibly more. Above 120 PPM (7 GRAINS) things
start to go downhill fast! For this reason, it is highly
recommended that ammonia solution lines runningfrom the ejector to the point of application be
avoided. These solution lines are subject to thesame build-up of deposits as the ejector nozzle.
Ammonia ejectors should always be installed directlyat the point where the amonia/water solution will be
added to the system.
Some installations have been known to installsofteners in the ejector supply water line. This works
well, but in some states the softener backwash
cannot be dumped by a commercial treatment plant(considered a ground water pollutant). Anothermethod for coping with (not solving) the problem isto install two ejectors in parallel and use ball valvesto operate one at a time. The ejectors have unions orother quick disconnect fittings so they can be easily
removed to clean the nozzles. There are many
possible variations on these ideas.
1 GRAIN HARDNESS = 17.1 PPM

CAUTION!!!!!
Do not store chlorine gas cylinders withAmmonia Gas Cylinders!

NH3 Materials/Installation

Copyright © 1997, Chemical Injection Technologies, Inc., Pub.No. 1297-1

Printed in U.S.A.