JPS6210319A - Heat retaining of tank in icy sea - Google Patents

Abstract

PURPOSE:To obtain the heat of a tank with good efficiency by using a simple structure in which a warm wind duct is provided in the internal space of a double shell structure, and warm waste gas is sent into the duct and circulated in the space. CONSTITUTION:The wall to be touched by open air and sea water of a marine structure having a water tank and an oil tank in its inside is of a double-shell structure consisting of an outer plate 1 and an inner wall 2 to be touched by water or oil. A warm wind duct 3 is provided in the internal space 8 of the double shell structure, and a warm wind outlet 4 is provided in the duct 3 and an opening 5 is provided in a partition wall 6. Waste warm gas from residential areas, Diesel engines, and heat source sections is sent into the space 8 from the outlet 4 by an air blower and discharged through the opening 3 to the outer air.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of keeping a tank warm for a marine structure in icy seawater, and particularly to preventing water, etc. in a tank from freezing by using warm exhaust.

[Conventional technology]

Figure 3 shows an example of marine structures in icy waters, with 51 residential areas and 32. Drilling e) 53e
34 is the frozen sea, and 35 is the ocean floor on which the artificial island 31 is installed.

As mentioned above, on the artificial island 61 installed in the icy sea area, the outside air temperature drops to about -50 degrees Celsius, so the water and oil stored in the tanks of the artificial island 31 (for last use) freeze. It may become unusable.

In order to prevent water, etc. in this tank from freezing, conventionally the fourth
As shown in the figure, each tank 36&~36n of the artificial island 31
Insulation tubes 37a to 37n are individually piped into the tank, and antifreeze heated by a boiler 38 is sent to the insulation tubes 37a to 37n to keep water, oil, etc. in each tank 36a to 36n warm. There is.

[Problem that the invention seeks to solve]

In the conventional heat retention method as described above, each tank 36a
- 36n, for example, heat insulation bulbs 37a to 37n in water.
The problem is that it is not easy to repair the piping, and it requires an independent boiler 381 to heat the antifreeze circulating in the heat insulation pipes 37a to 37n, which also requires extra fuel. was there.

The present invention has been made to solve these problems, and its purpose is to propose a simple and efficient method for keeping a tank warm in icy seas.

[Means for solving problems]

The method of keeping a tank warm in an icy sea according to the present invention is to connect a wall in contact with the outside air and seawater of a marine structure installed in an icy sea area and having an inner SVC water tank and an oil tank with an outer panel and an inner wall in contact with water or oil. A method of circulating hot exhaust air into the space within the double shell structure by installing a hot air duct in the space within the double shell structure and sending hot exhaust air into the hot air duct. It is.

[Effect]

In this invention, the Il that is in contact with the outside air has a double-shell structure, and by circulating hot exhaust air in the space within this double-shell structure, the outside air, the water tank, and the oil tank are isolated by the hot exhaust air, and each Keep the tank warm.

〔Example〕

FIG. 1 shows a partial cross-sectional configuration of an artificial island in a flooded area according to an embodiment of the present invention, in which 1 is an outer panel in contact with the outside air and seawater, 2 is an inner wall, and 3 is a structure between the outer panel 1 and the inner wall 2. A hot air duct installed in a double shell structure space.

4 is a warm air outlet provided in 3 (hot air duct), 5 is an outer panel 1
And inside! ! In the space between 2 is an opening in the bulkhead 6, and 7 is a water tank.

Hot exhaust air is sent to the hot air duct 6 configured as described above. Figure 2 shows a system diagram for collecting and supplying hot exhaust gas.

As shown in the figure, the hot air exhaust 21 after heating the residential area, the diesel engine exhaust 22, and the exhaust 23 from other compartments with heat sources such as the engine room and the compressor room are used as the hot exhaust. The hot air exhaust 21 in the residential area and the exhaust 23 in areas with other heat sources can be used as is.
The exhaust gas 22 of the diesel engine is heat recovered by a heat recovery device 24, and then purified by a desulfurization/soot removal device 25 before use.

This hot exhaust air is sent to the hot air duct 3 by the blower 26 27
After performing ventilation 28 into each space 8 of the double shell structure from the hot air outlet 4 of the hot air duct 6, each opening 61Fr
Exhaust 29 is carried out through the air to the outside air.

1 through the outer panel 1 and inner wall 2 from the space 8 of the double shell structure.
The amount of heat Q transferred per hour can be expressed by the following formula.

Q=ΔT−K−S (KcsllA) where ΔT is the outer plate 1. The temperature difference between the inside and outside of the inner wall 2, S is the temperature difference between the outside and the outer wall 1. The area of the inner wall 2 and K indicate the heat transmission coefficient.

The thermal conductivity of the steel plate is 6.32 Kca to h°C.

Now, if the temperature inside the space 8 of the double shell structure is maintained at 10°C and the temperature of the outside air is 50°C below freezing, then the temperature of the outer panel 1 is 1? The amount of heat Qo transferred per F/ is Qo = (5O-10) x 6.3
2x1 ” ” 80Kcaz/h.

Further, if the water temperature in the water tank 7 is set to a temperature that does not freeze, for example 2°C, 1? of the inner wall 2? The amount of heat QI transferred to P/A⇠υ is Ql = (2-10) x6, 32x 1 = 51Kc
at/h.

Assuming that the heat transfer from the space 8 of the double shell structure is only from the outer plate 1 and the inner wall 2, and there is no heat transfer to the other side,
The amount of heat QT transferred from the space 8 to the outside IN and the 1-A corner of the inside a2 is q〒=Q++q■=431 Keaj/h.

Therefore, the air volume V necessary for the space 8 of the double shell structure to maintain the temperature of 10° C. while discharging this amount of heat QT is obtained by the following equation.

Here, V is the specific volume, C is the specific heat, and ΔT1 is the temperature difference between the temperature of the hot exhaust and the space 8.

Now, the specific heat C of air is Q, 24 Kc&t/f#℃,
The specific volume mass is α83 Wl/Kg, and the hot exhaust temperature t-
When the temperature is 20°C, the above air volume V is as follows.

In fact, even hot exhaust gas of around 20°C can be fully utilized.

〔Effect of the invention〕

As explained above, this invention is designed to keep each tank warm by insulating the outside air and the water tank by circulating hot exhaust air in the space inside the double shell structure. This also has the effect of reducing fuel consumption in marine structures without requiring an independent heat source to keep each tank warm.

Also, since the hot air duct, hot air outlet, etc. are provided within the space of the double shell structure, it also has the effect of making repairs easier.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a part of an embodiment of the present invention, Fig. 2 is an operational system diagram of the above embodiment, Fig. 3 is a side view of an artificial island in icy sea water, and Fig. 4 is a conventional It is an explanatory view showing a heat retention method. 1...Outer panel, 2...Inner wall, 6...Hot air duct, 4
...Hot air outlet, 5...Opening, 7...Water tank. Agent: Patent Attorney Tadashi Sato Figure 1, 1 and 2

Claims (1)

[Claims] In marine structures that are installed in icy ocean waters and have internal water tanks and oil tanks, the walls in contact with the outside air and seawater have a double shell structure consisting of an outer plate and an inner wall that contacts the water or oil, and the double shell A method for keeping a tank warm in an icy sea characterized by providing a warm air duct in a space within the structure, supplying hot exhaust air into the hot air duct, and circulating the hot exhaust air into the space within the double shell structure. .