Removal
of
Chemical
Compounds
Removal
of
Chemical
Compounds
in
Wastewater
Treatment
Plantsin
Wastewater
Treatment
Plants


TreatmentTreatment


Biodegradation
Biodegradation
(
transformation/
mineralization)(

transformation/
mineralization)



Hydrolysis
and
photolysisHydrolysis
and
photolysis


Surface
volatilization
and
air
strippingSurface
volatilization
and
air
stripping


SorptionSorption


Ion
exchange
and
organic
binding
(
90Ion
exchange
and
organic
binding
(
90
­­
95%)

95%)



Adsorption
and
precipitation
(<
10%)

Adsorption
and
precipitation
(<
10%)
Removal
Mechanisms
for
Select
Removal
Mechanisms
for
Select
Groups
of
CompoundsGroups
of
Compounds


Heavy
Metals
Heavy
Metals
 
 
only
by
sorption
only
by
sorption
(
includes
precipitation)(

includes
precipitation)



Volatile
Organic
Compounds
(
VOCs)

Volatile
Organic
Compounds
(
VOCs)

 
 
biodegradation
and
volatilizationbiodegradation
and
volatilization


Hydrophobic
Organics
Hydrophobic
Organics
 
 
biodegradation,
volatilization,
and
biodegradation,
volatilization,
and
sorption
sorption
Heavy
Metals
Sorption
to
BiosludgeHeavy
Metals
Sorption
to
Biosludge


Cation
exchange
with
biopolymersCation
exchange
with
biopolymers


Bind
to
cell
walls
and
membranes
in
ionic
Bind
to
cell
walls
and
membranes
in
ionic
formform


Can
become
internalized
(
70%
of
Cr
(
III)

Can
become
internalized
(
70%
of
Cr
(
III)

intercellular)

intercellular)



Increased
removal
with
increased
pHIncreased
removal
with
increased
pH


Increased
removal
with
increased
sludge
Increased
removal
with
increased
sludge
ageage


Rapid
process
(
equilibrium
in
1
to
2
Rapid
process
(
equilibrium
in
1
to
2
hours)

hours)
Determinations
for
SARA
ReportDeterminations
for
SARA
Report
1.1.
Analytical
data
whenever
availableAnalytical
data
whenever
available


NPDES
discharge
monitoring
reports
NPDES
discharge
monitoring
reports
(
monthly
metals
and
quarterly
(
monthly
metals
and
quarterly
organics)

organics)



Sludge
analysis
for
BIFSludge
analysis
for
BIF


Gas
chromatography
on
influentGas
chromatography
on
influent


Analyses
for
Universal
Treatment
Analyses
for
Universal
Treatment
Standard
List
for
RCRA
LDR
ComplianceStandard
List
for
RCRA
LDR
Compliance


Additional
special
samplingAdditional
special
sampling
2.2.
Modeling
with
ToxchemModeling
with
Toxchem
+

+
Selection
of
ToxchemSelection
of
Toxchem
++



Used
an
inUsed
an
in
­­
house
model
until
midhouse
model
until
mid
­­
1990'
s1990'
s


Field
data
from
fullField
data
from
full
­­
scale
WWTP
and
pilot
scale
WWTP
and
pilot
plant
demonstrated
overestimation
of
air
plant
demonstrated
overestimation
of
air
emissionsemissions


ToxchemToxchem
commercially
available
and
commercially
available
and
recognized
by
EPA
as
one
of
the
accepted
recognized
by
EPA
as
one
of
the
accepted
models
for
Method
304models
for
Method
304


User
friendlyUser
friendly


Calculation
methods
wellCalculation
methods
well
­­
documenteddocumented


Estimations
compare
more
favorably
to
Estimations
compare
more
favorably
to
data
data
ToxchemToxchem
++
Demonstration
Demonstration
