COMPARISON OF FUEL GAS PROPERTIES

COMBUSTION PROPERTIES

FXD+
Natural Gas

FXD +Propane FXD +Butane ACETYLENE MAPP GAS NATURAL GAS PROPANE BUTANE APACHI/HPG

Flame Temp in Oxygen, F

5900 +

5900 +

6000

5875

5301

4600

4579

4925

5300

Total Heating Value after
Vaporization BTU/lb

28520

22896

22743

21500

21100

24800

19768

19494

22100

Heating Value of gas, BTU/ft3

1108

2700

3603

1480

2380

1050

2560

3374

2400

Burning Velocity in
Oxygen, ft/sec

16.6

14.3

12.5

22.7

15.4

15.2

12.2

11

15

Formation Reaction

Exothermic

Exothermic

Exothermic

Endothermic

Endothermic

Exothermic

Exothermic

Exothermic

Endothermic

Primary Combustion
Heating Value BTU/ft3

68

350

360

505

484

55

295

315

438

Secondary Combustion
Heating Value, BTU/ft3

1036

2270

3240

1134

1896

995

2268

3114

1962

Combustion Ratio,
O2 vs Fuel

2:1

2.06:1

1.9:1

1.5:1

3.5:1

2:1

4.7:1

1.8:1

3.1:1

SAFETY
Shock Sensitivity

Stable

Stable

Stable

Unstable

Relatively
Stable

Stable

Stable

Stable

Stable

Explosive Limits
in Oxygen, %

5.0 - 59

2.5 - 58

1.7 - 60

3.0 - 93

2.5 - 60

5.0 - 59

2.4 - 57

1.8 - 60

2.0 - 57

Explosive Limits
in Air, %

5.3 - 14

2.25 - 9.40

1.7 - 9.0

2.5 - 80

3.4-10.8

5.3 - 14

2.3 - 9.5

1.8 - 8.4

2.0 - 10.0

Maximum allowable
Use Pressure

Line

Cylinder

Cylinder

PSI 15

Cylinder

Line

Cylinder

Cylinder

Cylinder

Tendency to Backfire

Slight

Slight

Slight

Considerable

Moderate

Slight

Slight

Slight

Slight

Reactions with
Common Materials

Few Restrictions

Few Restrictions

Few Restrictions

Copper &
Silver Alloys

Copper & Silver Alloy

Few Restrictions

Few Restrictions

Few Restrictions

Few Restrictions

PHYSICAL PROPERTIES

FXD+propane Acetylene MAPP NG Propane APG
Specific Gravity
of Liquid (60F)
0.527

--

0.576

-- 0.507 0.527

Pounds Per
Gallon at 60F

4.24

--

4.8

--

4.22

4.38

Cubic Feet Per
Pound of Gas at 60F

8.46

14.5

8.85

23.6

8.45

9.2

Specific Gravity of
Gas (air=1) at 60F

1.55

0.906

1.48

0.555

1.55

1.42

Vapor Pressure
at 70F, psig

119

--

94

--

120

135

Boiling Range at
760 mm Hg, F

-45

-119

-36 to -4

-250

-44

-50

Latent Heat of
Vaporization BTU/lb

183

--

227

--

184

187