JP3095575B2 - Cycle plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed-loop cycle plant in which a working fluid is a mixed medium in which one component absorbs and condenses into the other component, and more particularly to an improvement in cycle operation control in such a plant. The present invention can also be applied to power plants utilizing low-temperature heat sources such as heat recovery, ocean temperature difference, and geothermal energy, absorption refrigerators, absorption heat pumps, and the like.

[0002]

2. Description of the Related Art The structure of a conventional cycle plant will be described with reference to FIG. In FIG. 3, reference numeral 1 denotes a turbine, and a first heat exchanger 3 is provided at a turbine outlet of the turbine 1 via a pipe 2, and further connected to a low-pressure condenser 5 via a pipe 4. I have. From the low-pressure condenser 5, the pipe 6 and the condensate pump 7 pass, one passes through the pipe 8 and the first flow control device 9 to the first heat exchanger 3, and the other passes through the pipe 1.
0, high-pressure condenser 12 through first liquid level controller 11
Respectively. The first heat exchanger 3 is connected to a separator 14 by a pipe 13. One of the separators 14 is a pipe 15, a second heat exchanger 16,
The liquid level controller 17 is connected to the low-pressure condenser 5, and the other is connected to the high-pressure condenser 12 by a pipe 18. From the high pressure condenser 12, a pipe 19, a liquid supply pump 20
Is connected to the boiler 21 and from the boiler 21 to the turbine 1. The boiler 21 also has a hot gas pipe 22
To the chimney 23. Reference numeral 24 denotes a low-pressure condenser cooling water pipe, 25 denotes a high-pressure condenser cooling water pipe, 26
Denotes a second heat exchanger cooling water pipe.

[0003] The liquid cycle will be described. The liquid condensed by the low-pressure condensate 5 is divided into a liquid flowing through a pipe 8 via a liquid condensing pump 7 and a liquid flowing through a pipe 10. After being controlled to a predetermined flow rate by the first heat exchanger 3, it is sent to the separator 14 through the first heat exchanger 3. The other liquid is controlled to a predetermined flow rate by the first liquid level controller 11 and flows into the high-pressure condenser 12.

[0004] The fluid flowing into the separator 14 is separated into vapor and liquid, and the vapor passes through a pipe 18 and is supplied to the high-pressure condenser 12.
Sent to The liquid passes through the second heat exchanger 16 and passes through the second heat exchanger 16.
The flow rate is controlled by the liquid level controller 17 and sent to the low-pressure condenser 5.

In the high-pressure condenser 12, the liquid flowing from the pipe 10 and the separated steam flowing from the pipe 18 are separated by the cooling water pipe 2.
5 is cooled by, for example, seawater, and is returned.

The fluid condensed by the high-pressure condensate condenser 12
9 and sent to the boiler 21 via the liquid supply pump 20. In the boiler 21, the steam is heated by, for example, a hot gas flowing through the pipe 22 to form steam, which is sent to the turbine 1.

After the fluid vapor flowing into the turbine 1 performs work, it is sent to the first heat exchanger 3 through the pipe 2, where it exchanges heat with the liquid flowing through the pipe 8. The fluid flowing out of the first heat exchanger 3 and flowing through the pipe 4 mixes with the liquid flowing through the pipe 15, flows into the low-pressure condenser 5, is cooled by, for example, seawater flowing through the pipe 24, and returns. The above is one cycle of the liquid cycle.

[0008]

In the conventional cycle plant, when there is a leakage of the working fluid, for example, from the turbine 1 to the outside, the flow rate flowing through the pipe 2 is reduced by the amount of the leakage.
Less. Therefore, when performing heat exchange in the first heat exchanger 3
The temperature of the fluid flowing from the pipe 13 to the separator 14
As a result, the separator 1
The amount of steam flowing through the pipe 18 from 4 to the high-pressure condenser 12 is
Decrease. Therefore, since the heat exchange amount in the first heat exchanger 3 is smaller than the initial plan in which the leak is not considered, the heat / mass balance of the entire loop differs from the initial plan. However, the liquid level of the condensate in the high-pressure condensate condenser 12 can be controlled by the first liquid level controller 11 regardless of the presence or absence of a leak.
Because it is controlled constant by the mixing ratio of the liquid flowing through the steam and the pipe 10 through the pipe 18 at the inlet of the high pressure medium condenser 12, it will vary with changes in the presence or absence or amount of leak leak, That is, the steam flowing through the pipe 18
As the amount decreases, the mixing ratio changes, and there is a problem that efficient operation of the loop cannot be achieved due to occurrence of leak. Prediction of the amount of leak occurring here is impossible with the current technology, and it is also impossible to control the mixing ratio constant using the amount of leak as a variable.

The present invention has been made in view of the above circumstances, and is directed to a closed cycle loop in which a working fluid or air leaks between the inside and the outside of a loop in which a working fluid is separated and mixed. It is an object of the present invention to provide a cycle plant that can maintain the initially planned efficient operation regardless of the presence or absence of a large leak.

[0010]

According to the present invention, there is provided, in accordance with the present invention, heat exchange of turbine exhaust from a turbine with a working fluid in a first heat exchanger and operation of the turbine exhaust heated in the first heat exchanger. The fluid is separated into vapor and liquid by a separator, the liquid separated by the separator is subjected to heat exchange with a cooling medium by a second heat exchanger, and the second heat is supplied to the turbine exhaust exiting the first heat exchanger. The liquid cooled in the exchanger is mixed, the mixed working fluid is condensed in a low-pressure condenser, and a part of the condensed liquid is supplied to the first heat exchanger as a working fluid, and the condensed liquid is supplied. Is mixed with the steam separated by the separator, the mixed working fluid is condensed by a high-pressure condenser, and the working fluid condensed by the high-pressure condenser is evaporated by a boiler and supplied to the turbine. Cycle with closed loop configuration In Holland, flow rate, or before the working fluid flowing from said low pressure medium condenser to the pressure medium condenser
Of the working fluid flowing from the separator to the high-pressure condenser.
Measure the flow rate, and according to the measured working fluid flow rate,
Of the working fluid flowing from the low-pressure condenser to the high-pressure condenser.
There is provided a cycle plant including a flow control device that controls a flow rate .

[0011]

According to the above-mentioned means, the flow rate of the liquid or vapor flowing into the high-pressure condenser is measured , and based on this amount , the flow rate of the liquid flowing into the high-pressure condenser is adjusted to a heat / mass balance as planned. It can be controlled based on the flow rate.

[0012]

FIG. 1 shows an example of a cycle plant according to the present invention. In FIG. 1, the same parts as those shown in FIG. 3 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, the closed cycle loop of the cycle plant is exactly the same as the conventional example of FIG. According to the present invention, the low pressure condenser 5 to the high pressure condenser 12
A second flow control device 27 that measures the flow rate of the fluid flowing through the pipe 10 and adjusts the fluid flow rate is installed in the pipe 10 to the pipe 10. The second flow control device 27 measures the flow rate of the fluid flowing into the high-pressure condenser 12 through the pipe 10 and based on the heat / mass balance when there is no fluid leak from the turbine 1 to the outside, for example. Control the flow rate. Accordingly, even if there is a fluid leak, the flow rate of the fluid flowing from the low-pressure condenser 5 through the pipe 10 to the high-pressure condenser 12 is controlled according to the amount of the leak. Steam flowing through pipe 18 and pipe 10
The mixing ratio with the liquid flowing through the loop is kept constant, and efficient operation of the loop is achieved.

FIG. 2 shows another embodiment of the cycle plant according to the present invention. In the drawing, the same parts as those shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. I do. According to the embodiment of FIG. 2, the second flow control device 27 measures the fluid flow rate for indirectly detecting a fluid leak with the steam flowing from the separator 14 through the pipe 18 into the high-pressure condenser 12. This is different from the embodiment of FIG. The second flow control device 27 measures the flow rate of the steam flowing into the high-pressure condenser 12 through the pipe 18, adjusts the flow rate of the liquid flowing into the high-pressure condenser 12 through the pipe 10, and The mixing ratio is kept constant.

[0015]

As described above, according to the present invention, the mixing ratio of the steam and the liquid flowing into the high-pressure condensate, regardless of, for example, whether or not the working fluid leaks from the inside of the closed cycle loop to the outside. Is kept constant, and the plant can always be operated with efficiency close to the initial plan.

[Brief description of the drawings]

FIG. 1 is a system diagram showing one embodiment of a cycle plant according to the present invention.

FIG. 2 is a system diagram showing another embodiment of the cycle plant according to the present invention.

FIG. 3 is a system diagram showing an example of a conventional cycle plant.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Turbine 3 1st heat exchanger 5 Low pressure condenser 7 Recondenser pump 9 1st flow control device 11 1st liquid level controller 12 High pressure condenser 14 Separator 16 2nd heat exchanger 20 Feed pump 21 Boiler

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Isamu Nagata 2-5-1 Marunouchi, Chiyoda-ku, Tokyo Inside Mitsubishi Heavy Industries, Ltd. (56) References JP-A-2-241909 (JP, A) JP-A-3 −9005 (JP, A) Japanese Utility Model 4-8706 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F01K 25/06 F01K 25/00 F01K 25/10

Claims (1)

(57) [Claims] 1. A turbine exhaust gas from a turbine is subjected to heat exchange with a working fluid in a first heat exchanger, and the working fluid heated in the first heat exchanger is separated into steam and liquid by a separator.
The liquid separated by the separator is heat-exchanged with a cooling medium in a second heat exchanger, and the liquid cooled in the second heat exchanger is mixed with the turbine exhaust flowing out of the first heat exchanger. The condensed working fluid is condensed in a low-pressure condenser, a part of the condensed liquid is supplied to the first heat exchanger as a working fluid, and the remainder of the condensed liquid is mixed with the steam separated by the separator. Then, in a cycle plant having a closed loop configuration in which the mixed working fluid is condensed in a high-pressure condenser and the working fluid condensed in the high-pressure condenser is evaporated by a boiler and supplied to the turbine, There is a flow rate of the working fluid flowing from the low-pressure condenser to the high-pressure condenser.
Or operation to flow from the separator to the high-pressure condenser
Measures the flow rate of the fluid, and according to the measured working fluid flow rate
Operating from the low-pressure condenser to the high-pressure condenser.
A cycle plant comprising a flow control device for controlling a flow rate of a fluid .