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Propane Standby Systems: An Overview

Table 1 Thermodyamic Properties of Normal Saturated Propane

Enthalpies and Entropies are referred to saturated liquid at -200 °F where the values are zero.

ATMOSPHERIC PRESSURE =14.73PSIA
TEMP

°F 		PRESSURE *
(PSI) 		SPECIFIC VOLUME *
(Cf / Lb)		    DENSITY *
(Lb / Cf)		 ENTHALPY **
(Btu / Lb)		 LATENT HEAT **
(Btu/Lb)		 ENTROPY **
(Btu / Lb / °F)
ABSOLUTE GAUGE LIQUID VAPOR LIQUID VAPOR LIQUID VAPOR LIQUID VAPOR
Temp APress GPress LSpVol VSpVol LDen VDen LEnthal VEnthal Latent LEntrop VEntrop
-50
12.6
‑2.10
0.02732
7.74
36.6
0.129
79.5
262.7
183.2
0.173
0.617
-45
14.4
‑0.30
0.02748
6.89
36.39
0.145
82.3
264.2
181.9
0.179
0.615
-40
16.2
1.5
0.02763
6.13
36.19
0.163
85
265.8
180.8
0.185
0.614
-35
18.1
3.4
0.02779
5.51
35.99
0.181
87.5
267.2
179.7
0.19
0.613
-30
20.3
5.6
0.02795
4.93
35.78
0.203
90.2
268.9
178.7
0.196
0.612
-25
22.7
8
0.02811
4.46
35.58
0.224
92.8
270.3
177.5
0.202
0.61
-20
25.4
10.7
0.02827
4
35.37
0.25
95.6
271.8
176.2
0.208
0.608
-15
28.3
13.6
0.02844
3.6
35.16
0.278
98.3
273.2
174.9
0.214
0.607
-10
31.4
16.7
0.0286
3.26
34.96
0.307
101
274.9
173.9
0.22
0.607
-5
34.7
20
0.02878
2.97
34.75
0.337
103.8
276.2
172.4
0.226
0.606
0
38.2
23.5
0.02985
2.71
34.54
0.369
106.2
277.7
171.5
0.231
0.605
5
41.9
27.2
0.02913
2.48
34.33
0.403
108.8
279
170.2
0.236
0.604
10
46
31.3
0.02931
2.27
34.12
0.441
111.3
280.5
167.2
0.246
0.603
15
50.6
35.9
0.0295
2.07
33.9
0.483
114
281.8
167.8
0.248
0.602
20
55.5
40.8
0.0297
1.9
33.67
0.526
116.8
283.1
166.3
0.254
0.601
25
60.9
46.2
0.02991
1.74
33.43
0.575
119.7
284.4
164.7
0.26
0.6
30
66.3
51.6
0.03012
1.6
33.2
0.625
122.3
285.7
163.4
0.266
0.599
35
72
57.3
0.03033
1.48
32.97
0.676
125
287
162
0.272
0.598
40
78
63.3
0.03055
1.37
32.73
0.73
128
288.3
160.3
0.278
0.597
45
84.6
69.9
0.03078
1.27
32.49
0.787
131.1
289.5
158.4
0.285
0.596
50
91.8
77.1
0.03102
1.18
32.24
0.847
134.2
290.7
156.5
0.292
0.596
55
99.3
84.6
0.03125
1.1
32
0.909
137.2
292
154.8
0.298
0.596
60
107.1
92.4
0.0315
1.01
31.75
0.99
140.6
293.2
152.6
0.306
0.595
65
115.4
100.7
0.03174
0.945
31.5
1.06
143.8
294.5
150.7
0.313
0.594
70
124
109.3
0.03201
0.883
31.24
1.13
147.5
295.8
148.3
0.321
0.594
75
133.2
118.5
0.03229
0.825
30.97
1.21
150.3
296.9
146.6
0.327
0.594
80
142.8
128.1
0.03257
0.77
30.7
1.3
154
299.1
145.1
0.335
0.593
85
153.1
138.4
0.03287
0.722
30.42
1.39
157
299.2
142.2
0.342
0.593
90
164
149.3
0.03317
0.673
30.15
1.49
160.3
300.3
140
0.349
0.593
95
175
160.3
0.03348
0.632
29.87
1.58
163.4
301.3
137.9
0.356
0.592
100
187
172.3
0.03381
0.591
29.58
1.69
166.8
302.4
135.6
0.363
0.592
105
200
185.3
0.03416
0.553
29.27
1.81
169.8
303.2
133.4
0.37
0.592
110
212
197.3
0.03453
0.52
28.96
1.92
172.8
304
131.2
0.376
0.591
115
226
211.3
0.03493
0.488
28.63
2.05
176.2
304.7
128.5
0.383
0.59
120
240
225.3
0.03534
0.459
28.3
2.18
179.8
305.2
125.4
0.391
0.589
125
254
239.3
0.03575
0.432
27.97
2.31
183.5
305.8
122.3
0.399
0.588
130
272
257.3
0.03618
0.404
27.64
2.48
186.8
306.1
119.3
0.406
0.587
135
288
273.3
0.03662
0.382
27.32
2.62
190
306.3
116.3
0.413
0.586
140
305
290.3
0.03707
0.36
27
2.78
194
306.5
112.5
0.422
0.585

*Based on material from Dana, Jenkins, Burick and Timm, Refrigerating Engineering, June 1926, Vol. 12, No. 12, page 403
**From Mollier Diagrams for Propane, W.C. Edminster, Standard Oil Co., (Indiana)



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