Document ID: EPA-HQ-OAR-2002-0059-0650
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2004-02-24T05:00Z

Date
Time
11/
7/
03
11:
30
a.
m.

Project
Name
CONTACT
REPORT
RICE
NESHAP
Project
Number
ESD3­
B­
1­
4
Alpha­
Gamma
Originator
Contact
Phone
Number
Jennifer
Snyder
Mike
Wyatt,
Johnson
Matthey
610
341
3429
General
Subject
I
called
Mike
Wyatt
at
Johnson
Matthey
in
response
to
this
public
comment
made
on
catalyst
deactivation:

"
Typically,
oxidation
catalysts
undergo
two
stages
of
deactivation:
a
period
of
rapid
deactivation
as
the
catalyst
adjust
to
the
thermal
and
gas
conditions,
typically
over
a
period
on
the
order
of
100
hours;
followed
by
a
period
of
slow
deactivation
that
occurs
over
thousands
or
tens
of
thousands
of
hours."

He
verified
that
there
are
two
periods
of
deactivation,
as
was
described
in
the
comment.
He
said
the
first
would
best
be
described
as
"
stabilization,"
and
would
be
more
on
the
order
of
20
hours,
but
this
depends
on
a
number
of
variables,
of
course.
The
longer
term
deactivation
rate
depends
a
lot
on
oil
consumption.
If
you
have
an
engine
which
burns
a
lot
of
oil,
then
your
deactivation
will
be
more
rapid.
They
design
the
catalyst
to
have
the
guaranteed
percent
reduction
at
the
end
of
its
useful
life
(
i.
e.
they
have
a
warranty
period).
I
asked
him
what
these
typically
were,
and
he
said
for
a
natural
gas
fired
engine,
2
years,
and
for
a
turbine,
which
burns
no
oil,
3
to
5
years.
He
gave
the
example
of
a
guarantee
for
90%
CO
reduction
to
have
an
efficiency
of
93%
after
its
degreening
period,
to
be
eventually
degraded
to
90%.
He
said
CO
deactivation
was
relatively
flat,
while
HC
deactivation
has
more
of
a
slope
to
it.
He
did
say
that
they
have
a
catalyst
installation
on
a
turbine
in
California
which
was
installed
in
1988,
which
is
still
in
operation
and
has
had
no
problems.
I
asked
him
if
this
is
typical
and
he
said
it
was
not
unusual,
but
this
is
the
oldest
installation
he
knows
of.
It
has
run
for
over
100,000
hours,
and
has
not
had
to
be
regenerated
or
remanufactured.
It
has
been
washed
many
times
on
site,
but
this
is
a
simple
wash
procedure
performed
by
the
operators.

Signed