74-10 DWP
Evaluation of Dana Retronox
EGR and UOP Oxidizing Catalyst Retrofits
On Two Medium Duty Vehicles
September 1973
Emission Control Technology Division
Office of Air and Water Programs
Environmental Protection ' Agency
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Background
Medium duty vehicles (6000 to 10,000 pounds GVW) have been
shown to have many similarities to light duty vehicles.
Characterization of technically feasible emission reduction
is an important input.when considering development of medium
duty exhaust emission standards. In addition, state authorities
have expressed interest in retrofit control for this vehicle
class. To provide technical input to these areas test work
was conducted on two medium duty vehicles retrofitted with
oxidizing catalysts and exhaust gas recirculation (EGR) systems.
Device Description
Dana Retronox EGR system and UOP oxidizing catalysts were
retrofitted to both a 1972 Chevrolet 3/4-ton pick-up truck
with a 350 CID engine and automatic transmission, and a 1972
Dodge stake truck with a 318 CID engine and standard trans-
mission.
The Dana Retronox EGR system employs an engine speed and ported
carburetor vacuum controlled EGR system, and an engine speed
controlled vacuum advance cut-off system. Both EGR and relative
spark timing retard have been shown to be effective in reduction
of total oxides of nitrogen. The Retronox system is installed
typically as per the attached figure 1. The EGR valve is
controlled by ported vacuum assuming the engine speed is above
the set point of the ignition operated speed-sensing valve.
The recirculated exhaust gas is introduced into the intake system
via the existing PCV plumbing. The distributor vacuum advance
is connected downstream of the speed-sensing valve. Thus, as
with the EGR, vacuum advance can only be activated above the
speed-sensing valve set point.
In both truck installations the engine speed-sensing valve
opened at 1200 to 1300 rpm and the vacuum operated EGR valve
closed at approximately 3 in. Hg vacuum. Both trucks were
retrofitted with UOP pellet-type, noble metal oxidizing
catalysts. Air pumps were required. The Chevrolet installation
incorporated two heavily loaded sixty cubic inch converters
(1.7 gm noble metal/catalyst). One was fitted to each exhaust
manifold of the 350 CID V8 engine. The Dodge installation
incorporated one moderately loaded 180 cubic inch low profile
converter (1.52 gm noble metal in catalyst).
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Test Program
Tests were performed on the Chevrolet and Dodge trucks in both
the stock and retrofitted configurations. Tests were conducted
according to the 1975 FTP as described in the November 15, 1972,
Federal Register. The vehicles were tested at various inertia
loads and rear wheel horsepower absorption levels. Inertia vs.
power absorption is presented in Table II. Steady state testing
was also conducted. No mileage accumulation was attempted during
this program.
Results
A summary of results from this testing is given in Table I.
At low mileage a minimum of 80% reduction in hydrocarbon and
carbon monoxide emissions was achieved with a minimum 40% re-
duction in oxides of nitrogen. Complete tabulation of test
results is given in Tables III and IV.
Conclusion
At low mileage the Dana Retronox EGR system/UOP oxidizing
catalyst retrofit of two medium duty vehicles demonstrated
consistent reductions in hydrocarbon and carbon monoxide
emissions in excess of 80% and a reduction of 40% or more
in oxides of nitrogen.
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"DftNPi "RETRONOX EGK SYSTEM
INSTALLATION
SPEED
. CONT'UEP
ECiR VRLV6
FtGURE J
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TABLE I
1975 FTP - Summary of Average
Results with and without Dana/UOP Retrofit
Chevrolet 3/4-ton Pick-up Truck
Baseline
Retrofit
% reduction
Baseline
Retrofit
% reduction
HC (gm/mi)
6500 Ib. inertia
CO (gm/mi)
NOx (gm/mi)
2.92
0.51
83
3.23
0.35
89
39.61
7.27
82
5500 Ib. inertia
44.28
3.14
93
6.58
4.02
39
6.43
2.74
57
Dodge Stake Truck
Baseline 7.99
Retrofit 1.15
% reduction 86
Retrofit
Retrofit
1.11
1.09
7000 Ib. inertia
81.93
11.66
86
6500 Ib. inertia
11.66
6000 Ib. inertia
11.12
7.49
4.07
46
4.36
4.07
Retrofit
0.97
5500 Ib. inertia
7.75
3.52
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TABLE II
Medium Duty Rear Wheel HP at 50 MPH
Inertia Rear Wheel Power
Ibs. HP
5500 22.7
6000 27.5
6500 32.3
7000 37.1
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TABLE III
Test Results on 1972 3/4-ton Chevrolet C-20
Pick-up with 350 CID engine
1975 FTP Results
No Emission Control (5500 Ib. inertia)
HC
CO
NOx
Average
2.97
3.85
2.86
3.23
3.23
37.11
56.11
38.95
44.06
44.28
Steady State No Emission Control
Idle
gm/5 min.
1.97
40.62
.04
1975 FTP
With
Average
15 mph
gm/mi
1.29
12.15
.93
30 mph
gm/mi
1.51
3.41
5.00
Results
Dana/UOP Retrofit (5500 Ib.
HC
gm/mi
0.32*
0.37
0.33
0.35
0.35
Steady State with
Idle
gm/5 min
0.14
0.73
0.07
15 mph
gm/mi
0.07
0.07
0.48
CO
gm/mi
3.08*
3.43
2.69
3.29
3.14
(22.7 HP
45 mph
gm/mi
1.86
16.64
8.96
inertia)
Dana/UOP Retrofit (22.7
30 mph
gm/mi
0.05
0.02
0.58
45 mph
gm/mi
0.03
0.03
1.32
7.29
6.11
5.90
6.43
6.43
@ 50 MPH)
60 mph
gm/mi
3.05
96.62
8.42
NOx
gm/mi
2.34*
2.43
2.88
2.91
2.74
HP @ 50 MPH)
60 mph
gm/nu.
0.05
0.18
3.09
HC
CO
NOx
HC
CO
NOx
* Test conducted at 17.4 hp at 50 mph instead of 22.7 hp,
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TABLE III con't.
1975 FTP Results
With UOP Cat.- No EGR (5500 Ib. inertia)
HC
gm/mi
0.33
0.32
Average 0.33
CO
gm/mi
2.95
2.71
2.83
NOx
gm/mi
5.94
5.36
5.65
1975 FTP Results
No .Emission Control (6500 Ib. inertia)
3.23
2.64
2.88
2.92
44.42
35.81
38.59
39.61
6.61
6.31
6.82
6.58
Average
Steady State No Emission Control (32.3 HP @ 50 MPH)
Idle
gm/5 mi
1.99
37.30
0.00
15 mph
gm/mi
0.52
6.28
0.48
30 mph
gm/mi
0.84
1.64
3.46
45 mph
gm/mi
0.83
5.63
6.56
60 mph
gm/mi
1.64 HC
15.25 CO
11.83 NOx
1975 FTP Results
With Dana/UOP Retrofit (6500 Ib. inertia)
HC
gm/mi
0.43
0.56
0.47
0.56
0.51
CO
gm/mi
5.07
7.98
6.56
9.48
7.27
NOx
gm/mi
3.43
5,
4,
,04
,09
3.53
4.02
Average
Steady State with Dana/UOP Retrofit (32.3 HP @ 50 MPH)
Idle
gm/5 mi
0.29
0.68
0.07
15 mph
gm/mi
0.07
0.00
0.77
30 mph
gm/mi
0.10
0.14
1.26
45 mph
gm/mi
0.06
0.09
4.12
60 mph
gm/mi
0.11
1.35
6.13
HC
CO
NOx
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TABLE IV
Test Results on 1972 Dodge Stake Truck
With 318 CID Engine^
1975 FTP Results
No Emission Control (7000 Ib. inertia)
HC
gm/mi
8.62
7.90
8.40
7,
7,
46
56
Average 7.99
CO
gm/mi
85.44
80.86
78.99
84.38
79.96
81.93
NOx
gm/mi
7.69
9.11
5.99
8.27
6.39
7.49
Steady State No Emission Control (37.1 HP @ 50 MPH)
Idle
gm/5 mi
4.95
148.69
0.14
15 mph
gm/mi
4.15
42.82
1.10
30 mph
gm/mi
2.43
3.57
5.43
45 mph
gm/mi
2.09
~6.88
9.17
60 mph
gm/mi
1.44
18.75
11.33
HC
CO
NOx
1975 FTP Results
With Dana/UOP Retrofit (7000 Ib. inertia)
HC
gm/mi
1.27
1.19
14
10
,04
Average
1.
1.
1.
1.15
CO
gm/mi
13.51
9.84
9.64
13.37
11.95
11.66
NOx
gm/mi
4.22
4.31
3.96
4.31
3.55
4.07
Steady State with Dana/UOP Retrofit (37.1 HP @ 50 MPH)
Idle
gm/5 mi
0.08
1.25
0.00
15 mph
gm/mi
0.29
0.92
0.14
30 mph
gm/mi
0.25
0.34
1.25
45 mph
gm/mi
0.18
0.41
3.38
60 mph
gm/mi
0.03 HC
0.93 CO
4.90 NOx
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TABLE IV con't.
1975 FTP Results
With UOP/Dana Retrofit (6500 Ib. inertia)
HC
gm/mi
1.04
1.18
Average 1.11
1975 FTP Results
CO
gm/mi
9.47
13.85
11.66
With UOP/Dana Retrofit (6000 Ib.
1.11
1.17
1.13
1.16
0.88
Average 1.09
Steady State with
Idle 15 mph
gm/5 mi ' gm/mi
0.05 0.34
0.96 1.06
0.15 0.66
11.01
9.63
12.46
13.38
9.11
11.12
NOx
gm/mi
4.35
4.37
4.36
inertia)
4.06
5.70
3.93
3.72
2.94
4.07
Dana/UOP Retrofit (27.5 HP
30 mph
gm/mi
0.26
0.00
1.63
1975 FTP Results
With UOP/Dana Retrofit (5500 Ib.
HC
gm/mi
0.95
0.99
Average 0.97
CO
gm/mi
8.01
7.49
7.75
45 mph
gm/mi
0.18
0.37
4.99
inertia)
NOx
git/mi
3.29
3.76
3.52
@ 50 MPH)
60 mph
gm/mi
0.10
0.96
8.91
HC
CO
NOx
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