73-26 AW
Effects of FID Oven and Sample Line
Temperature on the Measurement of
Hydrocarbon Emissions from Diesel Engines
May 1973
Emission Control Technology Division
Office of Air ง Water Programs
Environmental Protection Agency
------- Background In late December 1972, an Opel Rekord 2100D Diesel-powered sedan was delivered to the EPA facility in Ann Arbor, Michigan. The car was supplied by the General Motors Corp. at EPA request for investigation of exhaust emission as part of an ECTD technical feasibility study and evaluation of light duty Diesel vehicles. The car was also used by EPA as part of a program to investigate the measurement of hydrocarbon emissions from Diesel engines. It is that program which is reported here. The program consisted of a series of tests during which the hydrocarbon emissions were measured using the 1975 Federal test procedure (CVS 4-bag) and by simultaneous continuous analysis of the dilute exhaust using a Beckman 402 flame ionization detector. The purpose of the tests was to determine whether there was a particular oven or sample line temperature which gave optimum results when measuring hydrocarbon emissions. Vehicle Description The car is a 1973 Opel Rekord 2100D, 4-door sedan. Seating capacity is five persons. Mileage at delivery was about 3000 miles. The engine is a four-cylinder, four-stroke Diesel with a dis- placement of 2.1 litres and an advertised horsepower of 68 (SAE). The car is equipped with a three-speed automatic transmission and the test inertia weight was 3000 pounds. Test Program Standard instrumentation was used to measure CO, C02, HC and NOx.from the CVS sample bags. A Beckman 400 flame ionization detector (FID) was used to measure hydrocarbon concentration in the sample bags. For continuous analysis of the dilute exhaust a heated Beckman 402 FID was used, with the output signal recorded on a strip chart. The sample for the Beckman 402 was taken immediately downstream of the dilution box and delivered to the instrument through a heated sample line. The sample line was constructed of stainless steel wrapped with heating tape and asbestos insulation. An in-line filter was located in the line about 15 cm (6") downstream of the sample probe. The purpose of this filter was to prevent ------- contamination of the sample line and FID with soot from the Diesel exhaust. Two thermocouples were located in the sample line, one located about 20 cm (8") downstream of the in-line filter and the other about 8 cm (3") before the sample enters the FID. Sample temperature refers to the temperature of the sample flow delivered to the FID. A series of tests were run as directed in the Federal Register for 1975 vehicles. The purpose of these tests was to determine the effect of sample line and oven temp- erature of the FID when measuring hydrocarbon concentrations in the diluted exhaust. Test Program Cold start LA-4 tests were run at oven and sample line temperatures of 200ฐF, 250ฐF, 300ฐF, 350ฐF, and 375ฐF. In addition, steady state cruises were run at each oven temperature. The car was run at a steady speed (40 or 50 mph) until fully warmed-up while the sample line was heated to approximately 425ฐF. When the complete system had stabilized, the sample line heaters were shut off and the line allowed to cool to 200ฐF. A strip chart recording was made of the hydrocarbon concentration during the cooling-off period. The chart was checked for variations in hydrocarbon concentrations as a function of sample line temperature. Results The parameter in which we were most interested during these 1975 FTP tests was the ratio of Hot HC/Cold HC. Cold HC refers to the hydrocarbon emissions in grams per mile deter- mined by integration of the strip chart from the continuous analysis of the dilute exhaust. The ratio of Hot HC/Cold HC increases with increasing oven and sample line temperature from 200ฐF to 375ฐF. The rate of increase appears to be slightly less from 300ฐF to 375ฐF than from 200ฐF to 300ฐF. In the steady state tests, when sample line temperature was varied while holding oven temperature, the hydrocarbon con- centration increased steadily with sample temperature from 200ฐF to 425ฐF. A leveling off of the rate of increase occurred between 300-350ฐF. The results of the 1975 tests are given in Table I.
-------
-3-
Conclusions
The test results do not show a particular combination of
oven and sample line temperatures giving optimum results
when measuring hydrocarbon emissions. It appears that oven
and sample line temperatures should be in the range of 350ฐF
to 400ฐF to give best results.
-------
TABLE I
OPEL DIESEL
Mass Emissions
grams per mile
1975 FTP
Oven ง Sample
Test #
16-198
16-238
16-252
16-263
16-264
16-265
16-268
16-271
16-273
16-331
16-336
16-368
16-374
16-378
16-385
16-388
16-394
16-396
16-399
16-420
16-422
Cold HC
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
20
16
20
19
17
17
19
19
19
19
23
21
21
21
18
19
19
24
27
21
25
Hot HC
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.35
.39
.47
.45
.50
.48
.58
.48
.42
.58
.57
.48
.49
.42
.45
.48
.57
.70
.60
.62
.63
CO
1.46
1.07
1.27
1.20
1.24
1.17
1.19
1.27
1.26
1.36
1.36
1.36
1.34
1.42
1.37
1.31
1.23
1.40
1.39
1.44
1.44
co2
427.
410.
430.
417.
427.
419.
409.
411.
416.
405.
410.
409.
419.
402.
404.
407.
421.
416.
411.
426.
419.
NOx
23 1.
66 1.
61 1.
29 1.
13 1.
98 1.
67 1.
95 1.
10 1.
14 1.
37 1.
25 1.
29 1.
51 1.
25 1.
18 1.
22 1.
75 1.
29 1.
88 1.
36 1.
27
24
34
35
38
32
35
29
33
36
33
59
52
55
50
47
40
59
55
55
55
Hot HC/Cold HC Line T
1.
2.
2.
2.
2.
2.
3.
2.
2.
3.
2.
2.
2.
2.
2.
2.
3.
2.
2.
2.
2.
75
44
35
37
94
82
05
53
21
05
48
29
33
0
5
53
0
92
22
95
52
200
250
300
300
350
350
400
250
200
375
375
250
250
200
200
300
300
375
375
350
350
-------
A 0 U A B E ฃ
MADE IN- US
j- rm.E.n;
H-tfmS
HHIHEE
-H-4 f H-
r - f-T 'I T-
' LL" - tit
L-. : - . uft
f-l I I I I i i :
H-f fi-t-H^
-1-4-4-4 - -I- -
..4 i-}- -U-
2.0
200
250
300 350
Oven and Sample Line Temperature
'F
400
-------
I 0
I 0
1 INCH
* 0 U A B E F
y A o e IN USA
20 -4-
10
] -ganger
WtM i
H-H-H--. -
Us
-t-HH-hH
-ffl+R
-frr
MTi-mt:
Sample Line
450
|fcperature
-------
I A D E IN US*
40
ns :..
-ii-ttili
H
---
4t-
ฑ11
Tiftti
- +- \i*~Jr- .
i ifl^if
TfT
n~rrt
.
$0 -
H
4-- t- i-H
Tjlttfto
i "*"
'* ~ - -4 [ -;
Ttrrf:[rr
-,. . 1 . . . r . -u
..t!iuft,4
. - j. : i J I L 1
-r4* - *~
30
tt'tf
4.1.1
-Wf
tt^H1
4-1
-f-
--ป44
t-[ -i
T
n-
i~r
44 P
J j-4-Li-: - i-
I ' '-i I-
n': M-'i-;-r|
. ;-=-4.t 4..J.-J. I.
sm\
-
ii
zrt :ฑT
_- LJ_
wr-
rt-
i .
-'4-
20
r"t~t
=f-
11:
ftf
t-r--
W'..^
44-44-M
-f-
tu
i
:W4:ffF
i-ri
.. -i.
!~i~; i ;
-r-r1 l-j-
-tJH"
tt
4;-R
t-r I
"! * *
EE-TTrS
i ;
f-f-i~
ฑฃt
H::ฑ
250
300 350
Sample Line Temperature ฐF
400
450
-------
* 0 U * ft t t
U A 0 t IN US
:HG iCbricen tratiions
I
'j-
pxr.!:: i
l-f4 i U. . .
:.,!!...,
: : : :c
0 raph
veri:300ฐF
4.
4T1
nil
\\m\-\
* < I- i I" !
i i l--, i , I i
jjtM-M
i
[
H -I 4
U-
44 !4
; iu.
.-4
-i
L ป-:
^UTi
4
J-4 ; i :
. r
; ! t|
MI:
i
hH-
M-
_4:
j-U.
titt
M
I "
h-4
m
-i--
; 14
i!
11
! l i -
' t !
iflltt
srป
44+W4
;;[;:;
'!-' i
T ;-+ ] ;-j-|-
i ' ;--t i
r-j- |-+ 4 t- -{-f -' '*
ttt-1
44-
H
.! I
4:
CH--
t
ti: tf41
-.4 I
f:
:ฑ.t
t
!()
H
1-UlHii
ft!:
-H-H-
i!l!i t
- 4-
1"--
ft
r
F
.
tm
iru i
-rij
!-(--
ป i H !-t-
-t I- i -)' i r
; -1 4-i
H4-f
.(f; ; , : ,
TI i i i r
r
-l- f
t
r - . 1 i- 1-4- !
4 i ! I i 1 M
< I r
t-44i-ii
iii'.
4
i- t -i
-
ir n
-li^j
! ; i t t-t
mif
I~M
4
i
Tt'iiili-r
tHr!4t1 '
-}-!-
-t--f I
: it
l {4
-t--! t
1J '
250
300
350
400
Sample Lin^^e
mperature
450
-------
INC t>APt" N'j. 1 7 8 O . 1 C
CH.J'I-J sปCTio*-toxio r
Cancer tratio.ns
HC :
PPM C
40 'rapH| i
6ven:373c!l
fM-l-i i i
250
300 350
Sample Line Temperature ฐF
400
450
-------
I INCH'
M A 0 C IN US*
30
20
10 r
HC qq
* ! :
i
t
r
1
r
i
i
-4
i
t"
i-
-t
:
i i
1;
i
:
:
--
.
...
^
t-t
i
-f
i!
t
t
. i
-
_L
..-
;'
1
i
1
-
I
-
~
t
nqen
G3
i
t
;
:
i i
-
t l
; ;
i
.1.
t
t-
_.- -
"
i
-11
-.
'
i
i
t
r
'
.
j-
-
"
<
t
i
~t.
l .
4} i
rr
i-f
it.
tratilari
T
I
L I
'
t~
hP
ft
f
S
.
t
r
4
a :
* i :
t i
r i ,
1
j
I
!,
H
"j i
j
i
I--
-
-
*
_.
i
-
'
-
-
-~
'-
-
-
-
...
:
-
-
-
(--
|-
t
i
-i-"
-l-
T
i
-t
r
t
k
-
-
. t
i
~
* r
frf
i!
'
;
...
-
-
-_.
t
1
-
-
-
-
-
-
-
"
-
^
-
\
\
t
i
,
It
-
-
...
-
t
i
r
i-
-
-
].
r
:H
-I f-
t ;
4 j t
-
.
*--
i
-
-
-
-
~
;
i
:
Tt;,
tff4
, -r j- -
h t"
j '
4
tt
ri
- 1:
E
[
i
i
t--
r
I
!
j i
(
!
i
"
'-
:
-
-
.
4-
4
i
' -
.
-
-
-
-
-
W
i- t t ' t
! ' t ; H
j i- ! !-! i
1 ! - !
! : i " '
H
j
,
[ii
r
r. i
250
...
-
"4-
-
i
i
:
,. i ._.,..
j
..
-
^
i
r
-| r *
r
i .1
t
i ._
! ;
-
[
-
:
-
-
i
-
:_
i i
i'!"
-
r
i -
-
-
-
-
-
.
r
-.
J
-
if
.
*
1 1
- L i
.
-4 4
t- f t :
i
i
-
|
7
i
1
] : r 1-
] '.
-
-
-
)
j-
1
"
-
]
y
-
ป
f"
1
-
-
--
-
-
-
-
.1
-
r i
-r
-
.
i
. ;
rli:!
L
- r
j
T
-
:! i
-H
.-I .
;
-|_; :
ji.u
300
-
-
-
-
-
'.'-
-
; I
; * -
i
f -1
-
;
-
-
-
-
-
i
i
\\
~
t.
i
!
-
-
;
-
i
-
-
.KJ
-
-
-
~
...
-
-
-
-
.
-
:
=
:
T
r
"j
1
"
i
i-.
i
i~
.
-
-
-i
...
^~
1;-
4-
j-
-
-
i
. .i
i
t
-
--
-
:
.
-
-
^
!
i
i
f r!
':'!'"
i
i i
t
i
'
-
i
4-
"t
- t"
i
t
L-
- t
t
t
.
-
--
:-f-
-
7
-
-
-
1.
|.:
i H
i i
-U
1
M-4- ;
- i :
.
-
-
-
"
-
-
-
'
1
-
i
f
.
i
1 j
r :
n
\
\ '
L
1
i ;
i !
-11
I -J
M-
. 4-
H-
H
. i
i i
;
| t
i
f-
r!
ii
1 t
i' I
- - -
.
t
t
t-
j
i
i
i
j.
1
l
l
t
;t .
I
\
1
*
!
i
:
;
1
.:
-
i
-l
t
t
l
-!
i
.4
i
t
i
I.
1
h!'
-1-
i
i
]
i
t
. |. . . '. . . j.. . .
40 Imptt ,
Oven;3SC
II,:; j
)..;.,
' ' : \
i ; ! i It
i ! i ; 1
!!-:;!
, i 1 . I
i .... I
i ! i I i i
1 i ' i -
i 1 t < > ;
ft! M !
' t
t ' i '
ill..)
\ ':'.':'.',
i 1 i : i j
! ; i ! ; !
'
i1
i
i
.
i -
i
r
i
;:;:;! {
350 400
45
Sample Lin^ffemperature ฐF
-------
3.0
2.0
1.0
CO .
grams per
. , . . i. 4
t
;--; - -
*
.
' :
1
T , |- -4 .- - .
^ : r t r i
i-l
i
mile
* t
. . , : . .
' i
, i i .
< -
' . -
. *
, ! .
_ ; i(g 4 .
,
, i
- - . . r . . .
- . ' .
' ' 1 i
i i i
' .
hi,. , . : j.
|
i *
| f - ' t - ; , I
.:.;::; i t
1 ; i !
" : : L.-:7i !
41!
, . . . !
1 ' ' ! -
' .
i i
> ;
'. ' ' L r , I 1 I
. r . ; 1
i . .
.'.'.'.
i
.; i-i i : : '
II,, : . . -
1 1 . ' . . .
T i . '
I * .. .*_...
!
1 . "*
' 1
1"i ; ; .'
'
.^4..;.' .. | i._j-4-
t ! .! i_i , ..4+.
4- -, - - 4 ^ , .. 4
j . ; . . .
.
. .
v -t f
J .........
r* : r : i
tl. i : i , : LI.
t-j ^
:i_i' ILL.: .:;.;'
. .t j ......
-
I
,,.... .._j ...
. . . . *- . .
*- - -
,
T ;
; . , i
i
i
i- ป
; LL ' : : : ; 4
, , i . , . . . t
... ... ,
:-(+- 4 -t -
1 ,
... : : | ij j
1 , . . . I ; ,
: 'in ' '
i i
'ซ- i
1 :.:,...,
! ' ! . .
1 : ' '
: i i ;..;..
! i 1 ' 1 ' ' '
1 1 r . , .
i 1 i
i h t '
| i T t ;
it4-!"' '
:..;ซ,.:
a
I , . a, . . . . t
^.f.;:.4.ฃ
-ป!].,...
CO mas
odomet
: '
1 ' '
6K , 0>
. . .- ffl fei . .
-
1
Opel Dies
s emission
er reading
***:E:ฎ . :
.61 ...
0'
~ " "
el
s vs .
12 ฃ
5000
6000
Odometer-Kilometers
7000
-------
10 '0 I I 1 C M
* 0 U A B ฃ C
D I IN US
Cojltd tfiag
grams '. per
PC
mile '
-1 i
.Opel Diejsjel
Cold HC emissiiqns
vs. Odometer <
reading
. I 4 i , j :
-t- : * ' '
TTpT:
i t-J H
: . .j J , . 4. J
,....!;
-
-f !
II
1 r t
:[ ii;
! '- 4-4 f-i
; i. - 1 \ .
-i
-H -
| -r
- -i i i 4
i , i i i
-fr , , f
:m&
ilirl
ai r t
-M-t.i
ii-!:
rLttrtt
i ! H'i"' t i
nrh Hr
F.
-U
l
w
. .* f }- } l- f :
r
* . i
! iTri-ii rt
1.1..: i- ^ i. ; : i
ilฅi'irf
U
-t i i-J-rฎ
l | t T"1 ' ' '
! 1
i ' r
t ! -f
ii r
<->eeป
i
1-.4
t I
| -i
l-f
ซ--Hi
H
6000
Odome tei^Ki 1 ome ter s
7000
-------
in. t ? 2 7 . i o
0X10 T (, I N C
A U U ป -l f t
M A 0 1 IN U '. i
NO* ! : : :
grams per
3.0
. . . -
mile
!NOx i:
odometer
Opel Diese
emissions
reading
vs
i i
t i
2.0
iiiiiiiii
liiiiiMi
i i
1 ; '
1.0
j I. I , :
4
.
-
mi
!.;i
fit
h : ! 1 ' i t i
itUUM
iH! i Hi!
i : ,. i (. .; , i
I
fl
I'**
1 ! ! ' i
(j:
;n
4
-t
5000
6000
Odometer-Kilometers
7000
------- |