UltraClear Nitrification System
The ammonia or nitrite effluent concentration of
wastewater treatment system is too high, fails
to meet EPA mandated levels or just needs to be
Problem: The ammonia or nitrite level of wastewater discharge from
a lagoon needs to be lowered to meet accepted or
desired levels established by the local
municipality or the Federal Government.
Solution: The UltraClear Nitrification System for wastewater
treatment plants or systems provides a
concentrated liquid biological solution for
reducing the ammonia and nitrite concentrations
in wastewater. The solution is achieved through
A reduction in ammonia level
General Information on Nitrification
Nitrification is the biological oxidation
of ammonia to nitrite. The nitrification process
consist of two steps:
Conversion of ammonia (NH3) to nitrite
Conversion of nitrite (NO2) to nitrate
is performed by the bacterium, Nitrosomonas.
is performed by the bacterium, Nitrobacter.
Various parameters play a key role in successful
nitrification. Among these are the following:
Presence of Required Bacteria:An obvious
requirement is the presence of Nitrosomonas and
Nitrobacter bacteria. However, their presence or
absence may be a function of the other
parameters listed below.
Aerobic Conditions: Nitrifying bacteria are aerobic bacteria,
which means they require dissolved oxygen in
order to metabolize, grow and reproduce.
Alkalinity: Alkalinity of water is a measure of its capacity to
neutralize acids. A variety of compounds,
including bicarbonates, salts of weak acids, and
hydroxides contribute to alkalinity. When
ammonia is oxidized during nitrification,
hydrogen ions (H+) are liberated. Alkalinity is
needed to neutralize these hydrogen ions. In
fact, 8.64 mg/l of alkalinity are consumed for
each mg/l of ammonia that is oxidized. Without
sufficient alkalinity, the pH of the system will
drop, and nitrification will slow down or even
pH: Nitrification works best when the pH is between 6.5 and 8.5. The
process slows considerably at pH values outside
Temperature: Assuming that dissolved oxygen (D.O.) remains constant,
nitrification efficiency decreases as the
temperature falls. Many plants have severe
nitrification problems during the cold winter
period. A related problem may occur during hot
summer weather. Since DO is less soluble in hot
water than cold water, it is sometimes difficult
to maintain necessary DO levels in the summer.
When this occurs, nitrification may become
inadequate during hot periods. Extreme weather
(hot and cold) can impair nitrification
Simultaneous Removal of BOD: From a practical point of view,
nitrification proceeds better when the
concentration of soluble BOD is low (less than
20 mg/l). Therefore, many treatment plants are
designed with two stages. The first stage is for
BOD removal. The second stage is for
nitrification. In some plants, BOD removal and
nitrification must occur in the same aeration
tank, trickling filter, or RBC. The BOD removal
efficiency of a plant is always an important
factor in nitrification efficiency.
Growth and Reproduction Rate of Nitrifying Bacteria:
Compared to heterotrophic bacteria, which
consume organic compounds, the growth and
reproduction rates of nitrifying bacteria are
quite low. Heterotrophic bacteria take as little
as 30 minutes to reproduce. Nitrifying bacteria
take several hours to reproduce. For every gram
of organic substrate consumed, roughly 0.4 grams
of new heterotrophic bacteria are produced.
However, for every gram of ammonia converted to
nitrate, less than 0.2 grams of nitrifying
bacteria are produced.
Chemical Inhibition of Nitrifying Bacteria:
There are only two main species of nitrifying
bacteria. Nitrosomonas and Nitrobacter. There
are varieties of chemicals that are known to
inhibit these bacteria, such as sulfides and
cyanides (among many others). Since there are
only two main species involved, nitrifying
bacteria are very susceptible to
chemically-based toxicity, shock or upset.
wastewater treatment plants (WWTP's) are subject
to discharge permits, which limit the amount of
ammonia that can be lawfully discharged.
Government permits and regulations influence
levels of ammonia and nitrite that may be
discharged into streams. The discharge of
ammonia or nitrite into a stream, lake or river
may cause oxygen to be consumed, thereby
lowering the dissolved oxygen concentration and
endangering the aquatic ecosystem.
Maintaining nitrification would be relatively
simple for wastewater treatment plants if they
operated in a 'steady state'. However, the
desired 'steady state' conditions do not exist
in the WWTP environment. For example, all
treatment plants experience significant changes
in daily flow, organic loading, nitrogen
loading, temperature, and concentrations of
toxic chemicals. The nitrification process can
be easily upset and lose efficiency with the
numerous changes that occur on a daily basis. Of
course, the most severe cases occur when a
facility violates its ammonia discharge limit.
These upsets may last only a short while (a few
days or weeks) or can be chronic problems.
In other cases, a plant may nitrify only some of
the time, incompletely, or not at all. Many
factors may be involved when nitrification is
inadequate. Among the most important are:
Inadequate physical plant design for
Inappropriate biological conditions.
Occasional process upset due to toxic
Occasional process upset due to hydraulic
Difficulty in establishing nitrification
when variations in seasonal permits exist.
Loss of nitrification during extreme
The degree of improvement from use of
The UltraClear Nitrification System
varies depending on which specific factors are
causing the problem. The primary benefit of The
UltraClear Nitrification System is designed to
help WWTP's to meet ammonia discharge permits.
Occasionally, there are other benefits from
system use. For example, a WWTP may be able to
maintain nitrification with lower sludge age or
less aeration input when The UltraClear
Nitrification System is in use.
The UltraClear Nitrification System can be used to:
Consistently Meet Nitrification Permit: Some plants, due to inadequate plant design, excessive
hydraulic or organic loading, or other
uncontrollable factors, violate ammonia
discharge limits on a regular basis. When the
plant is typically coming close but not quite
The UltraClear Nitrification System
will most likely bring the plant within
compliance. Ammonia levels that periodically
exceed permit levels can be reduced. Average
ammonia levels can be reduced.
Delay or Avoid Plant Expansion:
In some cases, a facility will consider
expanding in order to consistently meet existing
or pending nitrification limits. Often,
The UltraClear Nitrification System
for ammonia reduction can be used to meet permit
until the expansion is complete. As long as the
sole need is for improved nitrification, and not
for a more difficult situation such as better SS
or BOD removal,
The UltraClear Nitrification System
can potentially save a community the cost of
unnecessary plant expansion.
Recover Rapidly from Upsets: Without The UltraClear Nitrification
System in use, a hydraulic or chemical shock can
cause loss of nitrification that might last for
weeks. With The UltraClear System in use,
recovery occurs as rapidly as possible, often
within a day or two rather than weeks.
Production of Nitrifying Bacteria
The UltraClear Nitrification System for ammonia reduction produces massive numbers of
nitrifying bacteria. With use of the UltraClear
Nitrification System, a treatment plant receives
as many nitrifying bacteria in a single day as
the treatment plant would normally get in 30
days from the raw influent wastewater.
As discussed previously, nitrifying bacteria
have different requirements than heterotrophic
bacteria do. Heterotrophic bacteria consume
soluble organic carbon. And different
heterotrophic bacteria not only grow in water
with plenty of dissolved oxygen (D.O.), but with
low D.O., or even anaerobic conditions (no D.O.).
The conditions in raw wastewater are excellent
for growth of heterotrophic bacteria. There is
an abundant organic food source, varying amounts
of oxygen, and varying lengths of time available
for growth and reproduction (depending on the
residence time of sewage in the sewer pipes).
Many technical specialists will state that 'all
of the bacteria needed for successful biological
wastewater treatment are present in the raw
influent'. However, this is rarely the case with
The conditions required for growth of nitrifying
bacteria are not present in sewer collection
pipes (i.e., the collection system). Nitrifying
bacteria are strictly aerobic, meaning that they
require D.O. for growth and reproduction. The
collection system rarely has significant level
of D.O. Nitrifying bacteria do not grow well in
the presence of high concentrations of soluble
BOD. Of course, the soluble BOD level in the
sewage collection system is quite high.
The concentration of heterotrophic bacteria in
the collection system (raw influent wastewater)
is quite high, generally in the range of 10's of
millions of bacteria per milliliter (ml). These
bacteria are present in the waste that enters
the collection system (in human waste, for
example), plus heterotrophic bacteria grow and
multiply easily in raw influent wastewater.
However, nitrifying bacteria DO NOT grow in the
collection system environment. Plus, nitrifying
bacteria are not among those bacteria that are
typically enter the sewage stream as part of
human waste. Instead, the main source of
nitrifying bacteria is in rain water that enters
the collection system. As strictly aerobic
bacteria, nitrifying bacteria live in the top
few centimeters of top soil. When it rains, some
of the nitrifying bacteria are carried by
rainwater into the sewage system.
The situation in the winter is more adverse.
Again, the nitrifying bacteria live in the top
few centimeters of topsoil. When the soil
freezes, the nitrifying bacteria are
immobilized, and do not enter the sewer system
in sufficient quantities. Cold temperatures
alone inhibit nitrification. But, the lack of
nitrifying bacteria in raw sewage during the
winter conditions makes cold weather
nitrification even more challenging.
Due to many factors, the average concentration
of nitrifying bacteria in raw influent
wastewater is about 10 organisms per ml. Using
this value, it is simple to compare the number
of organisms the number of organisms fed to the
treatment plant by raw influent wastewater
compared to the number fed with the UltraClear
The following calculation is based on a
hypothetical 1 MGD (million gallon per day)
treatment plant. With a concentration of 10
bacteria per ml, the number of nitrifying
bacteria fed to the treatment plant in one day
by the raw influent is 38 billion bacteria per
day (10 nitrifying bacteria/ml times 1,000,000
gallons per day times 3,785 ml/gallon).
The UltraClear Nitrification System is designed to add as many nitrifying bacteria to the
treatment plant as would normally be added in
one month from the raw influent. The UltraClear
Nitrification System is designed to add
nitrifying bacteria at 30 times the rate
contributed by raw influent. The reason is
simple. Many WWTP's do not have an ammonia
permit in the winter period, but have an ammonia
permit restriction in warmer months. Experience
has shown that it takes an average of 30 days to
make the transition from a non-nitrifying mode
into permit-level nitrification. The UltraClear
System offers a solution for speeding-up the
What is Required for Using the UltraClear Nitrification System?
There are three basic parts to
The UltraClear Nitrification System.
First, The UltraClear System Growth Chamber.
Second, a six gallon pail of liquid of
concentrated nitrifying bacteria (UltraClear
Nitrifying Concentrate) and,
Third, dry powder bacteria and nutrients
(Powdered UltraBac) that are introduced to The
UltraClear Growth Chamber on a weekly basis.
See section on
The UltraClear Growth Chamber
for more specific details about the equipment,
installation and operation.
Selecting the Size of the UltraClear System?
Select The UltraClear Nitrification System for
ammonia reduction based on:
1) the flow rate of the WWTP and,
2) the aeration time (retention time) for the
See the following tables to determine the
appropriate UltraClear System:
For 6 to 12 hours retention time:
For 12 to 36 hours retention time:
Initial Set-up Cost for the UltraClear Nitrification System
The set-up cost for using the UltraClear
Nitrification System includes the UltraClear
Growth Chamber and the UltraClear UltraBac
Concentrate. The UltraClear Growth Chamber and
the UltraClear UltraBac Concentrate are common
start-up components for System 1000 through
Weekly Operating Cost for The UltraClear Nitrification System:
The weekly dose of the UltraBac is added to the
UltraClear Growth Chamber every seven days. This
allows the system to continuously operate as
long as this weekly process is repeated.
UltraClear Nitrification System versus 'Ready-To-Pour'?
Which should you use? You need to determine
which solution provides the best value and
benefits. The 'Ready-To-Pour' is not as
economical on a per day comparison, but also
does not require the investment of a start-up
system (i.e., UltraClear Growth Chamber),
set-up, installation cost and ongoing operation.
In addition, it can be used immediately upon
receiving it. Please note that the shelf life of
'Ready-To-Pour' UltraBac Concentrate is one year
after receipt at your facility, so the product
can be kept on hand to deal with nitrification
upsets in an immediate and timely fashion.
Ordering The UltraClear Nitrification System or 'Ready-To-Pour'
Call 800-847-8950 to order. All systems,
components and bacteria are shipped via FedEx
from our facility in Cleveland. Or, send a fax
to 1-866-637-1376 with details.
Where do you add the nitrifying bacteria
produced by the UltraCler System?
The finished product that you draw from The
UltraClear System Growth Chamber every seven
days should be discharged (or poured) to the
secondary treatment. The recommended location is
Single Stage Aeration tank: to the head of the aeration tank.
Multi stage unit:
to the point where nitrification is just
In general, add the finished product to the head
of the aeration tank.
Getting Started with the UltraClear
Go to the section on the
UltraClear Growth Chamber
for additional details about this part of the
system and requirements for utilities, space,
operation and other general issues.