Bulk blending mixing efficiency tests


Baley, H.L.; Cole, C.A.; Rutland, D.W.

Proceedings of 32nd Annual Meeting of the Fertilizer Industry Round Table: 143-155

1982


Controlled tests were made to compare the cylindrical mixer with the concrete-type mixer for bulk blending operations. Raw materials used were urea, diammonium phosphate, triple superphosphate, and granular potassium chloride. Results are given. The tests showed little difference; however, the results may differ with other mixers of either type.

Wednesday,
October
17,
1982
Morning
Session
Al.
V.
Malone,
Moderator
CHAIRMAN
FRANK
P.
ACHORN:
Our
moderator
for
this
morning's
session
needs
no
introduc-
tion
to
most
of
you.
Al
Malone
has
participated
in
the
Round
Table
for
a
long
time
almost
from
the
start.
He
has
been
a
Board
member
of
the
Round
Table
for
several
years.
Al
has
held
several
technical
and
manage-
ment
positions
with
Agway
and
now
is
Manager,
Engineering,
Safety
and
Environmental
Protection
for
the
Fertilizer
Division.
He
is
located
at
Agway's
main
offices
in
Syracuse,
New
York.
Here
is
our
long-time
friend
Al
Malone.
(Applause)
MODERATOR
MALONE:
Good
morning.
The
Round
Table
is
known
for
its
ingenuity
and
creativity.
For
this
morning's
interesting
session
we
are
bringing
you
speakers
who
are
creative.
One
of
the
obstacles
to
creativity
is
that
there
are
killer
phrases
which
discourage.
I
have
a
list
of
these
killer
phrases
today,
and
as
I
introduce
the
speakers
I
want
to
announce
some
of
those
phrases
that
our
creative
speakers
have
con-
quered.
Our
first
presentation
today
is
by
Carl
A.
Cole,
Jr.
Carl
is
a
graduate
chemical
engineer
of
Auburn
Univer-
sity.
He
has
worked
for
five
years
for
the
Tennessee
Valley
Authority
in
research
and
development,
provid-
ed
technical
assistance
to
the
fertilizer
industry,
and
helped
start
up
fertilizer
plants.
He
is
a
chemical
engineer
with
Frank
Achorn's
group,
the
Field
Engineer-
ing
Staff,
Division
of
Agricultural
Development,
Mus-
cle
Shoals,
Alabama,
and
has
coauthored
several
technical
papers
and
articles.
Carl
has
wrestled
and
pin-
ned
these
killer
phrases:
We've
never
done
it
that
way
before.
We
haven't
the
manpower.
It's
not
in
the
budget.
We're
not
ready
for
it
yet.
All
right
in
theory,
but
can
you
put
it
into
practice?
Too
academic.
What
will
the
customers
think?
He
will
be
discussing
"Bulk
Blending
Mixing
Effi-
ciency
Tests."
We
are
pleased
to
introduce
Carl
to
the
Round
Table.
(Applause)
Bulk
Blending
Mixing
Efficiency
Tests
Hubert
L.
Balay
Carl
A.
Cole
David
W.
Rutland
Presented
by
Carl
A.
Cole
In
1968
Bridger
and
Bowen
reported
results
from
tests
of
several
kinds
of
mixers
used
for
bulk
blending
111
.
Among
the
mixers
tested
were
a
2-ton
stan-
dard
concrete
mixer
with
fixed
inclined
axis
and
helical
flights
and
a
cyclindrical
rotary
mixer
78
inches
in
diameter
and
38
inches
long.
The
conclusion
was
that
the
cylindrical
rotary
mixer
did
a
good
job
of
mixing
and
that
the
standard
concrete
mixer
did
a
poor
job
of
mixing.
Logic
supports
Bridger's
conclusion.
A
concrete,
or
concrete-type
mixer,
must
be
stopped
and
reversed
for
discharge.
Hoffmeister
showed
that
most
segregation
in
bulk
blends
is
the
result
of
segregation
of
particles
of
dif-
ferent
sizes
when
the
fertilizer
mixture
is
allowed
to
form
a
cone
[21
.
Since
it
appears
that
such
a
cone
will
be
formed
in
the
bottom
of
a
concrete-type
mixer
when
the
mixer
is
stopped
for
reversing
to
empty
the
mixer,
it
was
assumed
that
all
such
mixers
would
segregate,
or
unmix,
materials
which
had
previously
been
well
mixed.
Also
large
particles
tend
to
empty
first
from
this
kind
of
mix-
er
as
a
result
of
the
auger
action
of
the
flights
during
discharge.
A
distinction
must
be
made
between
a
standard
concrete
mixer
of
the
kind
that
Bridger
tested
and
the
concrete-type
mixer
specifically
built
to
mix
fertilizer.
The
concrete-type
fertilizer
mixer
is
usually
an
expand-
ed
version
of
a
standard
concrete
mixer
but
its
capacity
may
vary
from
2
to
10
tons
and
the
axis
of
the
mixer
is
usually
at
a
lower
angle
to
the
horizontal
than
in
the
standard
concrete
mixer.
The
flights
are
also
sometimes
narrower.
Several
tests
by
TVA
in
cooperating
plants
using
materials
directly
from
plant
bins
indicated
that
the
concrete-type
mixer
blended
almost
as
well
as
the
cylin-
drical
mixert
3]
.
Results
obtained
from
two
of
these
tests
are
shown
in
tables
1
and
2.
However,
the
raw
materials
used
in
the
two
plants
varied
greatly
in
analysis,
size,
shape,
and
density.
There
were
also
questions
about
the
143
mechanical
condition
of
the
mixers,
which
were
more
than
20
years
old.
Methods
used
in
obtaining
and
preparing
the
samples
were
also
different.
Thus,
the
tests
did
not
provide
a
sound
basis
for
evaluating
effec-
tiveness
of
the
two
kinds
of
mixers.
Although
data
indicate
that
concrete-type
mixers
do
not
do
a
good
job
of
mixing,
most
bulk
blend
plants
in
the
United
States
use
them
because
they
cost
less
than
cylindrical
mixers.
Also,
package
units
are
available
complete
with
weigh
hopper
and
feeding
and
discharge
devices
which
can
be
easily
and
inexpensively
installed.
Because
of
the
number
of
concrete-type
mixers
being
us-
ed,
the
limited
nature
of
Bridger's
tests,
and
the
unex-
pected
results
of
random
field
tests,
another
set
of
con-
trolled
tests
to
compare
the
cyclindrical
mixer
with
the
concrete-type
mixer
was
performed.
The
tests
were
conducted
in
two
mixers
located
near
TVA's
National
Fertilizer
Development
Center
(NFDC).
Both
were
relatively
new
and
in
good
condi-
tion.
The
cyclindrical
mixer
(figure
1)
was
a
1-ton
mixer
at
the
International
Fertilizer
Development
Center
(IFDC)
pilot
plant
in
Muscle
Shoals,
Alabama.
This
mixer
had
been
used
only
once.
The
mixing
time
recom-
mended
by
the
manufacturer
(90
seconds)
had
been
used
in
the
previous
run
and
results
were
not
as
good
as
ex-
pected.
To
overcome
this
problem,
the
mixing
time
was
increased
to
180
seconds
for
the
current
tests.
The
concrete
mixer
(figure
2)
was
recently
installed
in
a
plant
near
Athens,
Alabama.
Although
the
mixer
had
a
capacity
of
8
tons,
only
a
1-ton
batch
was
mixed
to
lower
costs
and
preparation
time.
Also,
a
better
com-
parison
could
be
made
if
both
mixers
were
mixing
the
same
size
batch
rather
than
operating
at
capacity.
The
manufacturer
of
the
concrete-type
mixer
confirmed
that
the
mixer
should
have
about
the
same
mixing
efficiency
with
a
1-ton
batch
as
with
an
8-ton
batch.
Raw
materials
were
taken
from
storage
at
two
local
fertilizer
plants
and
from
the
TVA
pilot
plant.
These
materials
were
urea,
diammonium
phosphate
(DAP),
triple
superphosphate
(TSP),
and
granular
potassium
chloride
(KC1),
all
manufactured
by
different
com-
panies.
Urea
was
obtained
from
the
TVA
falling
curtain
granulation
pilot
plant.
The
DAP
was
shoveled
manual-
ly
from
bulk
piles
into
bags.
All
other
materials
were
prebagged.
Two
samples
of
each
material
were
obtained
with
a
sampling
cup
during
the
riffling
procedure
from
bags
picked
at
random.
A
chemical
analysis
was
obtain-
ed
on
each
sample
(table
3).
The
formula
was
prepared
by
mixing
500
pounds
of
each
material
per
ton
of
fer-
tilizer
produced.
Based
on
the
chemical
analyses
the
grade
formulated
was
15.9-23.2-15.0.
Each
raw
material
was
divided
into
A
and
B
por-
tions
by
riffling
(Figure
3).
The
A
portions
were
used
in
the
cylindrical
mixer,
the
B
portions
in
the
concrete-type
mixer.
A
screen
analysis
of
each
portion
was
made
and
the
percent
and
cumulative
percent
size
distribution
of
the
raw
materials
were
determined
(Tables
4
and
5).
The
largest
deviation
in
size
in
each
case
was
between
the
urea
and
the
potash,
31.88
percent
on
side
A
and
28.56
percent
in
side
B.
Laboratory
results
indicate
that
blend
materials
which
diverge
more
than
20
percent
result
in
blends
with
high
segregation
tendencies
121
.
Therefore,
the
materials
were
chosen
so
that
there
was
enough
divergence
for
coning
to
occur
(if
there
was
a
problem
during
discharge
of
the
concrete
mixer),
but
not
so
ex-
treme
that
such
divergence
would
not
be
experienced
in
common
used
raw
materials.
To
insure
that
differences
in
weighing
did
not
occur,
raw
materials
for
all
tests
with
both
mixers
were
weigh-
ed
on
an
Electronic
Flexure
Base
Platform
Scale,
Model
4848
manufactured
by
the
Electrical
Scales
Corpora-
tion,
Santa
Rose,
California.
It
has
an
accuracy
guaranteed
to
1
part
in
5,000.
The
weighing
operation
is
shown
in
Figure
6.
After
weighing,
500
pounds
of
each
raw
material
was
taken
to
the
1-ton
cylindrical
mixer
at
the
IFDC
pilot
plant,
placed
by
hand
in
the
mixer,
and
mixed
for
180
seconds.
The
mixer
was
then
discharged
and
samples
obtained
using
AOAC
procedures
for
stream
sampling
with
a
recommended
stream
sampling
cup.
The
adding
of
materials
to
the
mixer
and
the
sampling
process
are
shown
in
Figures
7
and
8.
As
each
cup
of
material
was
obtained,
the
cup
was
dumped
onto
3-inch
PVC
pipe
split
in
half
and
subse-
quently
into
sample
bottles.
The
split
PVC
pipe
was
used
so
that
the
sampling
cup
could
be
emptied
quickly
without
spilling.
The
sample
could
then
be
placed
in
a
numbered
sample
bottle
without
slowing
down
the
sampling
process
and
without
danger
of
spilling
the
sample.
As
many
samples
as
possible
were
obtained.
After
sampling,
each
sample
was
submitted
to
the
NFDC
general
analytical
laboratory
for
N,
P2
05
,
and
K2O
analysis.
Only
total
P2
05
was
determined
since
this
was
adequate
for
this
experiment.
This
explains
the
high
P
2
O
5
analysis
of
the
TSP.
After
all
samples
were
obtained,
the
test
was
repeated
with
a
second
set
of
rif-
fled,
preweighed,
raw
materials.
After
the
cylindrical
rotary
mixer
tests
were
com-
pleted,
the
second
portion
of
riffled
preweighed
materials
was
taken
to
the
plant
with
the
concrete-type
mixer
and
the
sequence
of
mixing
and
collecting
samples
repeated
exactly
as
with
the
cylindrical
mixer.
Mixing
time
was
5
minutes
with
this
mixer
rather
than
3
minutes
to
conform
with
recommended
mixing
practice.
Analyses
of
samples
obtained
from
both
mixers
are
shown
in
Tables
6
and
7.
The
formulated
amount
of
nitrogen
was
15.9
percent.
Average
nitrogen
content
of
the
cylindrical
horizontal
mixer
samples
was
15.4
per-
cent
for
the
first
test,
and
15.7
percent
for
the
second;
both
are
slightly
lower
than
the
formulated
amount.
For
the
concrete-type
mixer
nitrogen
content
was
15.3
per-
cent
for
the
first
test,
and
15.6
percent
for
the
second;
these
are
also
slightly
lower
than
the
formulated
amount
of
nitrogen.
The
standard
nitrogen
deviation
for
the
cylindrical
mixer
was
0.45
for
the
first
test
and
0.49
for
the
second.
For
the
concrete
mixer
the
standard
nitrogen
144
Table
1
Analysis
of
10-10-10
Grade
Bulk
Blended
Fertilizer
Exit
Cylindrical
Rotary
Mixer
(Plant
A)
Sample
Time
(sec)
I.
N
%
P
2
0
5
%
K
2
0
10
10.5
10.7
12.5
20
9.9
9.8
11.1
30
9.7
10.6
10.3
40
10.3
11.3
10.1
50
b
X
10.3
11,4
9,7
10.1
10.8
10.7
S
c
0.33
0.64
1.11
a.
b.
Sample
obtained
as
mixer
discharged
Average
c.
Standard
deviation
Table
2
Analysis
of
15-10-10
Grade
Bulk
Blended
Fertilizer
Exit
Concrete-Type
Mixer
(Plant
B)
Sample
Time
(sec)
%
N
%
P20
5
%
K
2
0
14.1
10.2
9.2
14.2
10.8
8.9
14.2
9.7
10.0
14.0
10.6
10.3
14.0
10.1
10.7
14.6
10.3
11.1
14.4
10.2
11.3
14.7
9.3
12.2
15.2
10.1
12.8
13.8
13.6
11.2
14.3
10.5
10.8
0.415
1.17
1.23
a.
Average
b.
Standard
deviation
4
9
16
21
26
31
36
40
45
51
S
b
Table
3
Chemical
Analysis
of
Materials
Useg
for
Tests
of
Bulk
Blending
Mixers
Material
%
N
%
P
2
0
5
%
K20
Triple
superphosphate
47.0
Triple
superphosphate
47.0
Potash
60.1
Potash
tfammonium
phosphate
17.5
46.2
60.1
Diammonium
phosphate
17.4
45.9
a.
Samples
taken
from
two
bags
chosen
at
random
deviation
for
the
first
test
was
0.42
and
0.68
for
the
sec-
ond.
On
nitrogen
the
cylindrical
rotary
did
slightly
bet-
ter.
The
formulated
amount
of
P
2
O
5
was
23.2
percent.
Average
P
2
O
5
analysis
for
the
cylindrical
mixer
was
24.0
percent
in
test
1
and
24.2
percent
in
test
2.
Standard
deviation
was
0.41
for
test
1
and
0.91
for
test
2.
For
the
concrete-type
mixer
the
average
P
2
O
5
in
test
1
was
24.2
percent
and
the
average
in
test
2,
24.0
percent.
The
stan-
dard
deviation
for
the
first
test
was
0.33
and
0.41
for
the
second.
The
P
2
O
5
analysis
for
both
mixers
was
about
one
percent
higher
than
the
formulated
amount.
Means
for
P
2
O
5
samples
from
the
two
mixers
were
exactly
the
same;
standard
P
2
O
5
deviations
for
the
concrete-type
mixer,
however,
were
slightly
better
than
those
for
the
cylindrical
rotary
mixer.
The
formulated
amount
of
K
2
O
was
15.0
percent.
The
mean
for
the
first
test
with
the
cylindrical
mixer
was
14.7
percent
and
for
the
second
test,
15.1
percent.
Stan-
dard
K2
O
deviation
for
the
first
test
was
0.60
and
for
the
second
test,
0.67.
For
the
concrete
mixer
the
means
were
15.1
percent
and
14.8
percent,
respectively,
and
the
standard
deviations,
0.58
and
0.57.
For
K
2
O
th
e
concrete-type
mixer
did
slightly
better.
The
sample
analyses
shown
in
Tables
5
and
6
are
plotted
on
Figures
9,
10
and
11.
Although
these
tests
show
little
difference
between
the
two
mixers,
it
should
not
be
concluded
that
all
cyclindrical
rotary
mixers
and
concrete-type
mixers
do
an
equally
good
or
bad
job.
These
tests
were
performed
only
to
add
more
data
to
that
already
available.
More
tests
must
be
made
to
provide
a
statistically
accurate
conclusion
and
data
that
can
be
used
to
design
the
best
mixer
possible.
In
the
meantime,
owners
of
different
kinds
of
bulk
blend
mixers
should
be
encouraged
to
try
to
determine
the
efficiency
of
their
own
mixers.
145
Screen
Analysis
TVA/IFDC
Bulk
Blend
Tests
Side
A
Raw
Materials
Screen
Scale
Urea
DAP
TSP
KC1
Time:
10
Minutes
Time:
10
Minutes
Time:
10
Minutes
Time:
10
Minutes
Weight
Between
%
Between
Cum.
%
(Total
%
on
each
Weight
Between
%
Between
Cum.
%
(Total
%
on
each
Weight
Between
%
Between
Cum.
%
(Total
%
on
each
Weight
Between
%
Between
Cum.
%
(Total
%
on
each
Openings
Tyler
U.S.
Milli-
Inc-es
meters
Mesh
No.
Sieves Sieves
Sieve)
Sieves
Sieves
Sieve)
Sieves
Sieves
Sieve)
Sieves
Sieves
Sieves)
D.131
3.327
6 6
0.1
0.04 0.04
1.4
0.50
0.50
0.2
0.07
0.07
7.3
2.99 2.99
0.0;3
2.362
8
8
71.1
28.23
28.27
62.9
22.42
22.92
52.4
18.16
18.23
64.4
26.38
29.37
-
,.365
1.651
10
12
151.7
60.22
88.49
139.1
49.59
72.51
150.3
52.08
70.31
66.5
27.24
56.61
:.055
1.389
12
14
22.4
8.89
97.32
41.8
14.90
87.41
46.5
16.11
86.42
31.8
13.03
69.64
',.3-6
1.163
14
16
5.6
2.22
99.54
19.6
6.99
94.40
23.6.
8.18
94.60
29.6
12.13
81.77
3.0323
0.833
20 20
1.0
0.40
99.94
12.4
4.42
98.82
14.2
4.92
99.52
33.0
13.52
95.29
0.0000
0.0000
Pan
Pan
99.94
3.3
1.18
100.00
1.4
0.48
100.00
11.5
4.71
100.00
Totals
251.9
99.94 99.94
280.5
100.00
100.00
288.6
100.00
100.00
244.1
100.00 100.00
Table
5
Screen
Analysis
TVA/ITDC
Bulk
Blend
Tests
Side
B
Raw
Materials
Urea
Time:
10
Minutes
DAP
Time:
10
Minutes
TSP
Time:
10
Minutes
KC1
Time:
10
Minutes
Screen
Scale
Weight
Between
Sieves
%
Between
Sieves
Cum.
%
(Total
%
on
each
Sieve)
Weight
Between
Sieves
%
Between
Sieves
Cum.
%
(Total
%
on
each
Sieve)
Weight
Between
Sieves
Between
Sieves
Cum.
%
(Total
%
on
each
Sieve)
Weight
Between
Sieves
Between
Sieves
Cum.
%
(Total
%
on
each
Sieves)
Openings
Tyler
Mesh
U.S.
No.
Milli-
Inches
meters
0.131
3.327
6 6
0.1
0.04 0.04
1.7
0.66
0.66
0.5
0.20
0.20
7.8
3.52 3.52
0.093
2.362
8
8
72.1
29.17
29.21
63.3
24.49
25.15
48.1
18.98
19.18
62.3
28.11
31.63
0.065
1.651
10
12
147.2
59.55
88.76
132.8
51.37
76.52
133.0
52.49
71.67
63.3'
28.57
60.20
0.056
1.389
12
14
22.1
8.94
97.70
34.2
13.23
89.75
39.3
15.51
87.18
29.4
13.27
73.47
0.046
1.163
14
16
5.0
2.02
99.72
15.9
6.15
95.90
19.6
7.74
94.92•
25.8
11.64
85.11
0.0323
0.883
20
20
0.•6
0.24
99.96
8.6
3.33
99.23
11.4
4.50
99.42
25.3
11.42
96.53
0.0000
0.0000
Pan Pan
0.1
0.04
100.00
2.0
0.77
100.00
1.5
0.59
100.01
7.7
3.47
100.00
Totals
247.2
100.00
100.00
258.5
100.00
100.00
253.4
100.01
100.01
221.6
100.00
100.00
Table
4
Table
6
Analysis
of
15.9-23.2-15.0
Bulk
Blended
Fertilizer
From
Cylindrical
Rotary
Mixer
at
IFDC
Test
1
Test
2
Sample
Sample
Time
(Sec)
P205
K
2
0
Time
(Sec)
N
P
2
0
5
K
2
0
1
15.4
24.4
14.2
2
16.3
23.1
15.5
5
15.9
23.9
14.1
5
16.0
22.7
16.3
8
15.4
24.1
14.7
10
16.3
23.1
15.6
11
15.0
24.7
14.3
16
15.9
23.a
15.2
14
15.8
23.4
14.9
23
16.3
23.7
15.2
17
15.4
24.3
14.1
28
16.5
23.5
15.0
22
15.4
24.0
14.6
34
15.5
23.7
16.0
27
15.9
24.6 13.6
39
15.2
25.0
15.0
30
15.5
23.3
15.2
45
15.6
24.2
15.1
33
14.6
23.9
15.1
51
15.9
23.8
15.6
37
15.6
23.9
14.8
58
16.1
24.8
14.1
40
14.8
24.5
14.6
63
15.1
25.0
15.2
44
15.5
23.9
14.4
70
15.3
24.6
14.7
48
15.2
24.0
15.0
76
15.4
25.2
14.2
52
15.1
23.7
15.3
83
15.4
26.0
13.8
56
15.7
23.5
15.2
88
14.9
24.9
14.9
58
14.8
23.9
16.1
76
15.9
24.2
14.2
82
16.4
23.4
15
,
5
Ra
15.4
24.0
14.7
a
15.7
24.2
15.1
S
b
0.45
0.41
0.60
X
S
b
0.49
0.91
0.67
a.
Average
b.
Standard
deviation
Table
7
Analysis
of
15.9-23.2-15.0
Bulk
Blended
Fertilizer
From
Concrete-Type
Mixer
at
Athens,
Alabama
Test
1
Test
2
Sample
Time
(Sec)
N
P
2
0
5
K
2
0
Sample
Time
(Sec)
N
P205
K
2
0
7
14.9
23.8
16.0
12
15.3
24.8
14.2
11
15.1
24.7
15.1
16
17.0
23.5
13.6
14
15.4
24.0
15.3
21
15.9
24.5
14.2
18
15.9
23.9
15.1
25
15.9
24.0
14.6
21
15.5
24.3
14.9
28
16.3
24.0
14.4
24
15.2
24.2
15.7
32
16.2
23.6
14.5
28
15.4
24.1
14.8
36
15.7
24.2
14.7
31
15.4
24.6
14.6
39
15.7
23.8
15.1
34
15.9
23.5
14.1
43
15.3
23.9
15.1
38
14.8
23.6
16.3
48
14.2
23.9
15.7
42
15.7
24.4
14.9
51
14.8
24.1
15.3
46
15.5
24.4
14.5
55
14.8
24.6
15.1
49
15.7
23.9
15.3
60
15.2
23.4
15.6
53
14.6
24.2
15.9
65
15.7
23.5
14.8
58
15.5
24.3
14.8
70
15.4
24.0
15.2
65
14.6
24.2
15.0
X
a
15.3
24.2
15.1
R
a
15.6
24.0
14.8
S
b
0.42
0.33
0.58
S
b
0.68
0.41
0.57
a.
Average
b.
Standard
deviation
4.
4
.
4
11
,
to
4
1.•
del.
4
)•••••
••••
11119"..•
0
FIGURE
1
CYLINDRICAL
ROTARY
MIXER
rib
FIGURE
2
CONCRETE-TYPE
MIXER
'
s
II
:or
FIGURE
3
DIVIDING
RAW
MATERIALS
L
P
ERC
ENT
R
ETAINED
PERCEN
T
RETAI
NED
CUMULATIVE
SIZE
DISTRIBUTION
FOR
FOUR
COMPONENT
BULK
BLENDED
FERTILIZER
SIDE
A
"
*
100
90
80
70
rZ .
/.
//
60
/••
LEGEND
50
0
UREA
----_A
DAP
40
__.
—.0
TSP
—X
POTASH
30
r•
20
*
USED
WITH
CYLINDRICAL
ROTARY
MIXER.
10
0
+6
+8
+10
+12
+14
+20
FINES
TYLER
MESH
SIZES
FIGURE
4
CUMULATIVE
SIZE
DISTRIBUTION
FOR
FOUR
COMPONENT
BULK
BLENDED
FERTILIZER
SIDE
B
"
*
co
co
c‘i
LEGEND
O
UREA
---
A
DAP
•0
TSP
—X
POTASH
/
*
USED
WITH
CONCRETE-TYPE
MIXER
/
/Y
1/
.
6
8
10
12
14
20
FINES
TYLER
MESH
SIZES
FIGURE
5
100
90
80
70
60
50
40
30
20
10
0
151
S
-
j I
4
11114
g
-10
,
-
t
I
.
/
Pt--
FIGURE
6
WEIGHING
RAW
MATERIALS
-I
I
.1•1•
4
ti
/or
---
dm.
I
'-
p
IP
FIGURE
7
CHARGING
ROTARY
MIXER
17
4,
1
":••••
.•
7;:iqi4;•f-
11
'"
4..
FIGURE
8
SAMPLING
ROTARY
MIXER
NITROGEN
ANALYSES
VS.
ELAPSED
UNLOADING
TIME
FOR
BULK-
BLENDED
FERTILIZER
16
15
LEGEND
14
0
TEST
A
-
1
A
TEST
A-
2
0
TEST
B
-
1
13
X
TEST
6-2
THEORETICAL
VALUE
"A
"
-
4
THEORETICAL
VALUE
"8
I
I
1
I
I
I
I
I
I
I
I
I
I
i
1
I
1
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
ELAPSED
TIME,
SEC.
FIGURE
9
-4- -4-
153
A
/
\
/
\
/
\
A
/
p
A
,
A.
/
\
A
,
\
A
\
--
/
,
,
I
%
ef
/
V
PHOSPHATE
ANALYSIS
VS.
ELAPSED
UNLOADING
TIME
FOR
BULK
-
BLENDED
FERTILIZER
26
25
co
e
0_
24
I-
z
23
cr
0-
22
-I--
-I-
-I- -4- -+-
-4-
-4-
-I- -I-
-I- -I-
--I-
...........
_kk
A
LEGEND
)1e
/
0
TEST
A
-
I
A
TEST
A
-2
0
TEST
B-I
X
TEST
B-2
---
THEORETICAL
VALUE
"A"
THEORETICAL
VALUE
"B"
I
I
I
I
I I
I
I
.
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
ELAPSED
UNLOADING
TIME,
SEC.
FIGURE
10
POTASH
ANALYSES
VS.
ELAPSED
UNLOADING
TIME
FOR
BULK-BLENDED
FERTILIZER
17
16
PL
ANT
NUTR
I
ENT,
%
K2
0
d
15
_
•E;1
r
t
LEGEND
0
TEST
A
-
I
TEST
A
-
2
—L
CI
TEST
B
-
I
X
TEST
B-
2
--
THEORETICAL
VALUE
I
I
I I
I
I
1_
I
I
I I
I
I
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
ELAPSED
UNLOADING
TIME,
SEC.
FIGURE
11
14
13
154
REFERENCES
1.
Bridger,
G.
L.,
and
I.
J.
Bowen,
1968.
"Mixing
Ef-
ficiency
of
Fertilizer
Bulk-Blending
Equipment,"
Proceedings
of
the
18th
Annual
Meeting
of
the
Fertilizer
Round
Table,
pp
31-36,
Washington,
D.C.
2.
Hoffmeister,
George,
1973.
"Quality
Control
in
a
Bulk
Blending
Plant,"
Proceedings
of
the
TVA
Bulk
Blending
Conference,
TVA
Bulletin
Y-62,
pp
59-69.
3.
Internal
TVA
report,
H.
L.
Balay
to
F.
P.
Achorn,
March
1980.
MODERATOR
MALONE:
Thank
you,
Carl,
for
an
interesting,
timely
and
informative
paper.
It
provides
documentation
in
an
area
of
importance
to
many
of
us
involved
in
"Bulk
Blending."
(Applause)
Our
next
speaker
is
W.
Bennett
Spratlin
and
he
has
conquered
the
following
creativity
killer
phrases:
Somebody
would've
suggested
it
before,
if
it
were
any
good.
Too
Modern.
Too
Old-Fashioned.
Let's
discuss
it
at
some
other
time.
You
don't
understand
our
problem.
We're
too
small
for
that.
We're
too
big
for
that.
W.
Bennett
Spratlin
is
president
of
Johnson
City
Chemical
Co.,
Inc.,
Johnson
City,
Tennessee.
He
was
born
in
Florence,
Alabama,
and
has
a
B.S.
degree
from
Auburn
University.
He
was
employed
by
Agrico
from
1959
to
1974
in
various
manufacturing,
sales
and
technical
service
positions.
He
founded
Johnson
City
Chemical
Co.
in
1974.
It
has
grown
from
one
plant
and
seven
employees
and
one
million
in
sales
to
15
plants
and
warehouses,
90
employees
and
in
excess
of
12
million
in
sales.
He
is
founding
director
and
past
presi-
dent
of
the
Tennessee
Plant
Food
Educational
Associa-
tion.
He
is
past
president
of
Rotary
Club.
He
is
a
member
of
the
Board
of
Directors
for
Commerce
Union
Bank
and
is
a
member
of
the
President;s
Association.
He
was
elected
to
Who's
Who
in
the
South
and
South-
west.
He
is
married
and
has
three
children.
He
will
be
talking
about
"How
to
Produce
Bulk
Blends
That
Meet
State
Tolerances."
We
are
happy
to
introduce
you
to
the
Round
Table.
(Applause)
How
To
Produce
Bulk
Blends
That
Meet
State
Tolerence
W.
Bennett
Spratlin
I
would
like
to
begin
my
presentation
with
a
brief
introduction
to
Johnson
City
Chemical
Company
and
why
I
became
so
interested
in
meeting
state
tolerences.
My
career
in
the
fertilizer
industry
began
in
1959
with
the
old
American
Agrico
Chemical
Company
as
a
production
trainee,
I
gained
experience
in
all
phases
of
fertilizer
manufacturing
including
sulfuric
acid
produc-
tion.
In
1974,
the
opportunity
to
become
an
independent
business
person
presented
itself
and
I
purchased
an
Agrico
plant
in
Johnson
City,
Tennessee.
The
plant
had
been
converted
from
a
dry
mix
plant
to
a
blending
operation
in
1970
and
was
one
of
the
first
blending
operations
in
that
part
of
the
country.
For
those
of
you
who
are
not
familiar
with
East
Tennessee,
Southwest
Virginia,
and
Western
North
Carolina,
we
have
a
very
unique
agricultural
economy.
We
have
small
farms,
a
wide
variety
of
crops
such
as
corn
(for
silage),
tobacco,
cattle,
dairy,
vegetables,
ap-
ples,
small
grain,
etc.
A
large
portion
of
our
farmers
are
part
time,
and
depend
heavily
on
assistance
from
the
universities
on
what
to
do.
The
terrain
in
this
area
is
mountainous;
therefore,
we
cannot
bulk
spread
a
lot
of
this
area
nor
are
the
farms
large
enough
to
justify
bulk
loads.
We
also
still
have
people
that
do
not
mind
work,
and
a
lot
of
the
farms
are
a
family
effort.
I
tell
you
this
so
you
can
picture
in
your
mind
the
environment
we
operate
in.
The
blending
operation
was
unique
because
90
per
cent
of
all
tonnage
was
bagged.
I
became
very
concern-
ed
when
penalities
began
to
flow
in
for
deficient
analysis.
Our
reputation
was
at
stake.
Also,
it
was
get-
ting
too
expensive.
My
plant
manager,
Newell
Taylor,
and
myself
knew
that
the
material
was
in
the
bag.
We
pulled
numerous
resamples.
We
invited
the
state
officials
to
visit
our
plant.
We
begged
for
help.
What
profit
we
were
making
was
going
out
to
the
states
in
deficient
analysis.
Also
word
was
getting
around
that
we
could
not
make
good
fertilizer.
My
friend,
Curtis
Brummitt,
TVA,
introducted
me
to
Bud
Balay
and
George
Hoffmeister
who
were
doing
some
work
on
segregation
in
bulk
blends.
They
agreed
to
come
to
our
plant
and
assist
us
with
equipment
changes
in
order
for
them
to
conduct
their
tests
under
actual
field
conditions.
We
were
using
an
IC
Open
Mouth
Bagger
with
a
four
ton
holding
hopper.
After
the
hopper
modifica-
tions
were
made,
the
tests
were
made
and
our
segrega-
tion
problems
were
solved.
We
went
from
one
of
the
worst
records
in
our
area
to
one
of
the
best
in
one
year.
We
were
confident
that
our
product
would
meet
state
specifications
regardless
of
who
sampled.
We
had
the
results
to
prove
it.
Particle
size
had
very
little
to
do
with
the
result.
We
found
that
if
the
material
was
weighed
right
and
mixed
right,
it
would
stay
mixed
even
after
traveling
100
miles
by
truck.
Now
for
total
frustration.
In
order
to
improve
our
productivity,
we
decided
to
install
a
valve
packer
bag-
155