POWER GENERATING APPARATUS AND METHOD OF OPERATING POWER GENERATING APPARATUS

• US 20140223907A1
• Filed: 02/10/2014
• Published: 08/14/2014
• Est. Priority Date: 02/14/2013
• Status: Active Grant

• Current Assignee: Anest Iwata Corporation
• Original Assignee: Anest Iwata Corporation
• Inventors: FUJIOKA, Tamotsu, UNAMI, Atsushi, IZUMI, Takaaki
• Granted Patent: US 9,528,394 B2
• Time in Patent Office: Days
• US Class Current: 60/645
• CPC Class Codes: F01K 13/02 Controlling, e.g. stopping or starting
• CPC Class Codes: F01K 25/08 using special vapours
• CPC Class Codes: F01K 9/003 condenser cooling circuits

Abstract

Provided is a power generating apparatus including an evaporator configured to evaporate a working medium with a heating medium supplied from the outside of a working medium flow path, an expander to which a driven machine is connected and which is configured to convert expansion force of the evaporated working medium into rotational force to drive the driven machine, a condensing mechanism configured to condense the working medium discharged from the expander with a cooling medium supplied from the outside of the working medium flow path, the condensing mechanism having at least one heat exchanger pipe through which the working medium flows, a cooling water sprayer configured to spray cooling water as the cooling medium over the surface of one or a plurality of heat exchanger pipes of the at least one heat exchanger pipe, and a cooling fan configured to blow ambient air over the one or a plurality of heat exchanger pipes to evaporate cooling water attached to the surface of the one or a plurality of heat exchanger pipes, and a circulating pump configured to pressurize and supply the condensed working medium to the evaporator.

Claims

1. A power generating apparatus comprising:

an evaporator configured to evaporate a working medium with a heating medium supplied from an outside of a working medium flow path;

an expander to which a driven machine is connected and which is configured to convert expansion force of the evaporated working medium into rotational force to drive the driven machine;

a condensing mechanism configured to condense the working medium discharged from the expander with a cooling medium supplied from the outside of the working medium flow path, the condensing mechanism having at least one heat exchanger pipe through which the working medium flows, a cooling water sprayer configured to spray cooling water as the cooling medium over one or a plurality of heat exchanger pipes of the at least one heat exchanger pipe, and a cooling fan configured to blow ambient air over the one or a plurality of heat exchanger pipes to evaporate cooling water attached to a surface of the one or a plurality of heat exchanger pipes; and

a circulating pump configured to pressurize and supply the condensed working medium to the evaporator.

2. The power generating apparatus of claim 1, further comprising:

a liquefaction degree detecting device provided in the working medium flow path at an outlet side of the condensing mechanism and configured to detect a degree of liquefaction of the working medium; and

a control device supplied with a detected value from the liquefaction degree detecting device configured to control respective operations of the cooling water sprayer and the cooling fan on a basis of the detected value to control the degree of liquefaction to a target value or within a target range.

3. The power generating apparatus of claim 2, wherein the condensing mechanism further includes as temperature sensor detecting an ambient temperature of the at least one heat exchanger pipe;

the at least one heat exchanger pipe having a plurality of heat exchanger pipes provided in series to the working medium flow path;

wherein one heat exchanger pipe of the plurality of heat exchanger pipes is provided with the cooling water sprayer and the cooling fan, and another heat exchanger pipe of the plurality of heat exchanger pipes is provided with a second cooling fan configured to blow ambient air thereover;

the control device being configured to control an operation of the second cooling fan according to a detected value of the temperature sensor.

4. The power generating apparatus of claim 2, wherein the at least one heat exchanger pipe includes a plurality of heat exchanger pipes;

the condensing mechanism including;

the plurality of heat exchanger pipes provided in parallel to the working medium flow path;

the cooling water sprayer and the cooling fan, which are provided for each of the plurality of heat exchanger pipes; and

a switching device configured to selectively switch inflow of the working medium to the plurality of heat exchanger pipes;

wherein the control device controls the switching device to alternately perform, at each of the plurality of heat exchanger pipes, a cooling water spray step of allowing the working medium to flow into the heat exchanger pipe and of spraying cooling water over the heat exchanger pipe with the cooling water sprayer, and an evaporation step of blowing ambient air over the heat exchanger pipe sprayed with the cooling water.

5. The power generating apparatus of claim 4, further comprising:

one or a plurality of timers configured to measure an elapsed time of each of the cooling water spray step and the evaporation step;

wherein the control device controls the switching device on a basis of a time measured with the one or a plurality of timers.

6. the power generating apparatus of claim 2, wherein the liquefaction degree detecting device is a temperature sensor configured to detect a temperature of the working medium.

7. The power generating apparatus of claim 2, wherein the liquefaction degree detecting device is a flow sensor configured to detect a flow rate of the working medium.

8. The power generating apparatus of claim 2, wherein the liquefaction degree detecting device has a temperature sensor configured to detect a temperature of the working medium, and a flow sensor configured to detect a flow rate of the working medium;

the control device configured to judge, when a working medium temperature detected with the temperature sensor is below a threshold value, that the working medium has been all liquefied and cooled more than necessary, and to judge, when a flow rate of the working medium detected with the flow sensor exceeds a threshold value, that a proportion of vapor to liquid is high, and that cooling of the working medium is insufficient.

9. The power generating apparatus of claim 1, further comprising:

a heat exchanger provided in the working medium flow path, through which heat exchanger a refrigerant or brine for cooling the working medium circulates.

10. The power generating apparatus of claim 1, wherein the driven machine is an electric power generator.

11. A method of operating a power generating apparatus, the power generating apparatus including:

an evaporator configured to evaporate a working medium with a heating medium supplied from an outside of a working medium flow path;

an expander to which a driven machine is connected and which is configured to convert expansion force of the evaporated working medium into rotational force to drive the driven machine;

a condensing mechanism configured to condense the working medium discharged from the expander with a cooling medium supplied from the outside of the working medium flow path; and

a circulating pump configured to pressurize and supply the condensed working medium to the evaporator;

the condensing mechanism having a plurality of heat exchanger pipes provided in parallel to the working medium flow path, a cooling water sprayer and a cooling fan, which are provided for each of the plurality of heat exchanger pipes, and a switching device configured to selectively switch inflow of the working medium to the plurality of heat exchanger pipes;

the method comprising;

performing at each of the plurality of heat exchanger pipes, a cooling water spray step of allowing the working medium to flow into the heat exchanger pipe and of spraying cooling water over the heat exchanger pipe with the cooling water sprayer, and an evaporation step of blowing ambient air with the cooling fan over the heat exchanger pipe sprayed with the cooling water.

12. The method of claim 11, wherein an elapsed time of each of the cooling water spray step and the evaporation step is measured with one or a plurality of timers, and switching by the switching device is controlled on a basis of the time measured with the one or a plurality of timers.

13. The method of claim 11, wherein a temperature sensor configured to detect a temperature of the working medium and as flow sensor configured to detect a flow rate of the working medium are provided in the working medium flow path, and when the temperature of the working medium detected with the temperature sensor is below a threshold value, it is judged that the working medium has been all liquefied and cooled more than necessary, and when the flow rate of the working medium detected with the flow sensor exceeds a threshold value, it is judged that a proportion of vapor to liquid is high, and that cooling of the working medium is insufficient, and wherein, based on these judgment results, respective operations of the cooling water sprayer and the cooling fan are controlled.

14. The method of claim 11, wherein the working medium is further cooled by a heat exchanger provided in the working medium flow path, through which heat exchanger a refrigerant or brine circulates.

15. The method of claim 11, wherein the driven machine is an electric power generator.