JP2002285805A - Rankine cycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the lowering of energy efficiency by supplying power to a motor for a cooling fan. SOLUTION: A Rankine cycle 10 is composed of an expansion machine 12 to which steam is fed from a boiler 11 and which is rotated by the expansion work of the steam; a condenser 15 to condense the steam worked at the expansion machine 12; and a liquid pump 13 to supply a condensed working fluid to the boiler 11. In this case, the condenser 15 is provided with a cooling fan 14 to high-efficiently condense the working fluid and the liquid pump 13 to circulate the working fluid, and the cooling fan and the liquid pump are coupled to a rotary shaft 16 to obtain the power directly from the rotary shaft 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Rankine cycle in which the size and efficiency of a device are reduced.

[0002]

2. Description of the Related Art A conventional Rankine cycle (Rankin cycle)
-Cycle) is shown in FIG. Rankine cycle 1
A working fluid circulates through 10, a boiler 111 for evaporating the working fluid, and steam is supplied from the boiler 111,
An expander 112 that rotates by the expansion work of the steam, a condenser 115 that condenses the steam worked by the expander 112,
It is composed of a liquid pump 113 for supplying the condensed working fluid to the boiler 111 and the like. 2 shows a configuration in which a generator 117 is connected to the expander 112, and the generator 117 is driven by rotation of the expander 112 to generate power.

The condenser 115 is provided with a cooling fan 114 rotated by a motor 118 for efficiently cooling the working fluid, and the liquid pump 113 is provided with a motor 119 as a power source thereof.

[0004]

However, the motor 11 of the cooling fan 114 used in the condenser 115
8 and the motor 119 as a drive source of the liquid pump 113, since power must be separately supplied from the outside,
There was a problem that energy efficiency was reduced.

That is, the electric power supplied to these motors 118 and 119 is electric power generated by the power plant or the generator 117. 100% of the energy spent on power generation
It is not converted to electric power, but only part of the supplied energy is converted to electric power.

Further, the electric power is used by the motors 118 and 11.
When driving the motor 9, all of the motor 9 cannot be taken out as motive power because a part thereof generates heat loss or the like. Therefore, there is a problem that the energy efficiency cannot be increased accordingly.

Accordingly, an object of the present invention is to provide a Rankine cycle capable of preventing a reduction in energy efficiency due to power supply to a motor.

[0008]

According to a first aspect of the present invention, there is provided a boiler for heating a working fluid to produce steam, and steam supplied from the boiler to expand the steam. An expander whose rotating shaft rotates, a condenser for exchanging heat produced by the expander with heat by exchanging heat with a coolant, a coolant supply device for supplying the coolant to the condenser, and a condensed working fluid Cycle that has a liquid pump that supplies water to a boiler, prevents a decrease in energy efficiency due to supplying power to a motor or the like by using power of a rotating shaft as a power source of a coolant supply device and a liquid pump. It is characterized by doing so.

According to a second aspect of the present invention, the coolant supply device is a cooling fan that blows outside air to the condenser or a cooling pump that pressure-feeds the cooling water to the condenser, and receives the power from the rotating shaft. It is characterized by doing so.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a Rankine cycle 10 according to the present invention.
FIG.

The Rankine cycle 10 is a boiler 11 for generating a working fluid, and steam is supplied from the boiler 11, and the expander 1 is rotated by expansion work of the steam.
2, a condenser 15 for condensing steam condensed by the expander 12 and condensing it, a liquid pump 13 for supplying condensed working fluid to the boiler 11, and the like. FIG.
The generator 17 is connected to the rotating shaft 16 of the expander 12 shown in FIG. 1, and the rotating shaft 16 rotates to drive the generator 17 to generate power.

The condenser 15 is provided with a cooling fan 14 for efficiently cooling the working fluid, and the cooling fan 14 is attached to a rotating shaft 16. Further, the liquid pump 13 is also provided so as to obtain power directly from the rotating shaft 16.

[0013] The working fluid that has become steam in the boiler 11 in such a configuration is supplied to an expander 12 such as a steam turbine, and expands the drive fluid to drive the expander 12. Accordingly, the rotating shaft 16 rotates to drive the generator 17 connected to the rotating shaft 16, drive the liquid pump 13, and drive the cooling fan 14.

The working fluid from the expander 12 is supplied to the condenser 15, where it exchanges heat with the outside air and condenses. At this time, since the cooling fan 14 operates by the rotation of the rotating shaft 16, the resulting wind is blown to the condenser 15, so that the efficiency of heat exchange between the outside air and the like and the working fluid is improved.

The working fluid condensed in this way is pressure-fed by a liquid pump 13 operated by the rotation of a rotating shaft 16 and supplied to a boiler 11.

As described above, the cooling fan 14 and the liquid pump 13 for blowing the outside air and the like to the condenser 15 are not driven by the motor but by the power of the rotating shaft 16, so that the energy is lower than in the conventional case. Efficiency can be improved.

Further, since a motor is not required, the apparatus can be simplified and the size can be reduced.

In the above description, the cooling fan 1
4 and the case where the power of the liquid pump 13 is obtained from the rotating shaft 16 has been described. However, when such a Rankine cycle 10 is used for power generation or the like, a motor-driven device other than the cooling fan 14 and the liquid pump 13 may be used in many cases.

For example, in a Rankine cycle of a thermal power plant, an LNG vaporizer (heat exchanger) is provided for burning a fossil fuel such as LNG by a boiler, and seawater is used as a coolant for the LNG vaporizer or condensate. For example, seawater is used to cool a working fluid in a vessel.

When seawater is used, a pump for pumping seawater is required, and a motor is used as a power source for the pump. However, a power source for the pump may be obtained from a rotating shaft.

[0021]

As described above, according to the first aspect of the present invention, the power of the rotary shaft is used as the power source of the coolant supply device and the liquid pump. The electric power to be supplied becomes unnecessary, and a decrease in energy efficiency can be prevented.

According to the second aspect of the present invention, the coolant supply device is a cooling fan that blows outside air to the condenser or a cooling pump that pressure-feeds cooling water to the condenser. , The electric power supplied when these are driven by the motor becomes unnecessary, and a decrease in energy efficiency can be prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a Rankine cycle applied to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a Rankine cycle applied to a description of a conventional technique.

[Explanation of symbols]

 Reference Signs List 10 Rankine cycle 11 Boiler 12 Expander 13 Liquid pump 14 Cooling fan 15 Condenser 16 Rotary shaft 17 Generator

Claims (2)

[Claims] 1. A boiler that heats a working fluid to produce steam, a steam is supplied from the boiler, and an expander whose rotating shaft rotates by the expansion work of the steam; and the steam that has been worked by the expander is cooled. In a Rankine cycle having a condenser for exchanging heat with a material for condensation, a coolant supply device for supplying the coolant to the condenser, and a liquid pump for supplying a condensed working fluid to the boiler, the coolant supply device And a power source for the liquid pump, wherein the power of the rotary shaft is used. 2. The cooling material supply device is a cooling fan that blows outside air to the condenser or a cooling pump that pressure-feeds cooling water to the condenser, and receives the power from the rotating shaft. The Rankine cycle according to claim 1, wherein: