(BASIC TEMP.28℃, INPUT TEMP.：60℃CEMENT ＋ 28℃3/8” GRAVEL ＋ 28℃3/4” GRAVEL ＋ 26℃ SAND + 1℃ WATER)
| |
(1)
SPECIFIC HEAT
Kcal/Kg℃ |
(2)
WEIGHT
Kg/M3 |
(3)
WATER CONTENT
Kg/M3 |
(4)
HEAT EQUIVALENT
Kcal/℃M3
(=1x2+3) |
(5)
INPUT TEMP.
℃ |
(6)
TEMP. DIFFERENCE WITH 28℃ |
(7)
HEAT DISCHARGE
Kcal/M3
(=4x6) |
|
CEMENT |
0.22 |
330 |
0 |
72.6 |
60 |
32 |
2,323 |
|
3/8” GRAVEL |
0.22 |
700 |
7 (1%) |
161 |
28 |
0 |
0 |
|
3/4” GRAVEL |
0.22 |
350 |
3.5 (1%) |
80.5 |
28 |
0 |
0 |
|
SAND |
0.22 |
780 |
62.4 (8%) |
234 |
26 |
-2 |
-468 |
|
WATER |
1 |
80 |
|
80 |
1 |
-27 |
-2160 |
|
MIX HEAT |
|
|
|
|
|
|
2,586 |
|
TOTAL HEAT EQUIVALENT |
|
|
|
628.1 |
|
|
2,281 |
| TOTAL HEAT DISCHARGE |
TEMP OF CONCRETE AFTER MIX＝28℃＋ΔT
ΔT＝TOTAL HEAT DISCHARGE／TOTAL HEAT EQUIVALENT＝2,281／628.1＝3.63℃
TEMP AFTER MIX＝28℃＋ΔT＝28＋3.63＝31.63℃ ≧28℃ (BASIC TEMP)
It shows that mix concrete only with 1℃ ice water will fail to satisfy the basic requirement of concrete batching plant.
Recommendation:
1. Purchase a new Cold Air Chiller (75HP) to chill the gravel aggregate and improve the situation.
2. Reconstruct the original Ice Water System(100Tons) by adding a new Cold Air Chiller(20HP) to chill the gravel aggregate and improve the situation
