Exhaust heat recovery device and binary electricity generation device

Patent metadata

Field	Value
Publication number	US-10711993-B2
Application number	US-201715998958-A
Country	US
Kind code	B2
Filing date	Jan 25, 2017
Priority date	Feb 19, 2016
Publication date	Jul 14, 2020
Grant date	Jul 14, 2020

Abstract

An exhaust heat recovery device includes: a main passage through which an exhaust gas containing a corrosive component flows; a boiler which heats a heat medium using the exhaust gas; a bypass passage connected to the main passage so as to detour around the boiler; a regulation valve member which regulates a flow rate of the exhaust gas flowing into the boiler; a heat medium circuit which circulates the heat medium that is heated to be in a hot-water state by the boiler; a binary electricity generation device which recovers thermal energy from the heat medium in the heat medium circuit and generates electricity; and a valve control unit which controls an opening of the regulation valve member such that a temperature of the exhaust gas passed through the boiler is equal to or higher than a temperature of an acid dew-point of the corrosive component in the exhaust gas.

First claim

The invention claimed is:

1. An exhaust heat recovery device comprising:
a main passage through which an exhaust gas containing a corrosive component flows;
a boiler provided in the main passage, the boiler being configured to heat a heat medium using the exhaust gas so as to place the heat medium in a hot-water state;
a bypass passage connected to the main passage so as to detour around the boiler;
a regulation valve member configured to regulate a flow rate of the exhaust gas flowing into the boiler;
a heat medium circuit including a hot-water pump, the heat medium circuit being configured to circulate the heat medium that is heated so as to be placed in the hot-water state by the boiler;
a binary electricity generation device including a circulation circuit through which a working medium circulates, the binary electricity generation device being configured to recover thermal energy from the heat medium in the heat medium circuit and generate electricity;
a valve control unit configured to control an opening of the regulation valve member such that a temperature of the exhaust gas passed through the boiler is equal to or higher than a temperature of an acid dew-point of the corrosive component in the exhaust gas;
a temperature sensor configured to detect a temperature of the heat medium that is in the hot-water state; and
a pressure sensor configured to detect a pressure of the heat medium that is in the hot-water state,
wherein the valve control unit controls the opening of the regulation valve member such that the temperature of the heat medium is in a predetermined range and a supercooling degree of the heat medium is maintained in a state in which the supercooling degree has a predetermined value or higher.

2. The exhaust heat recovery device according to claim 1 , wherein
the regulation valve member includes a flow-rate regulation valve provided in the bypass passage, and
the valve control unit is configured to control an opening of the flow-rate regulation valve so as to increase an amount of a heat-source gas that flows into the bypass passage so that the supercooling degree of the heat medium has the predetermined value or higher.

3. The exhaust heat recovery device according to claim 1 , wherein
the regulation valve member includes a flow-rate regulation valve provided in the main passage, and
the valve control unit is configured to reduce an opening of the flow-rate regulation valve so that the supercooling degree of the heat medium has the predetermined value or higher.

4. An exhaust heat recovery device comprising:
a main passage through which an exhaust gas containing a corrosive component flows;
a boiler provided in the main passage, the boiler being configured to heat a heat medium using the exhaust gas so as to place the heat medium in a hot-water state;
a bypass passage connected to the main passage so as to detour around the boiler;
a regulation valve member configured to regulate a flow rate of the exhaust gas flowing into the boiler;
a heat medium circuit including a hot-water pump, the heat medium circuit being configured to circulate the heat medium that is heated so as to be placed in the hot-water state by the boiler;
a binary electricity generation device including a circulation circuit through which a working medium circulates, the binary electricity generation device being configured to recover thermal energy from the heat medium in the heat medium circuit and generate electricity;
a valve control unit configured to control an opening of the regulation valve member such that a temperature of the exhaust gas passed through the boiler is equal to or higher than a temperature of an acid dew-point of the corrosive component in the exhaust gas;
a temperature sensor configured to detect a temperature of the heat medium that is in the hot-water state; and
a pressure sensor configured to detect a pressure of the heat medium that is in the hot-water state,
wherein the valve control unit controls the opening of the regulation valve member such that the temperature of the heat medium is equal to or higher than a predetermined temperature and a supercooling degree of the heat medium is maintained in a state in which the supercooling degree has a predetermined value or higher in stopping the hot-water pump.

5. The exhaust heat recovery device according to claim 4 , wherein
the regulation valve member includes a flow-rate regulation valve provided in the bypass passage, and
the valve control unit is configured to control an opening of the flow-rate regulation valve so as to increase an amount of a heat-source gas that flows into the bypass passage so that the supercooling degree of the heat medium has the predetermined value or higher.

6. The exhaust heat recovery device according to claim 4 , wherein
the regulation valve member includes a flow-rate regulation valve provided in the main passage, and
the valve control unit is configured to reduce an opening of the flow-rate regulation valve so that the supercooling degree of the heat medium has the predetermined value or higher.

7. An exhaust heat recovery device comprising:
a main passage through which an exhaust gas containing a corrosive component flows;
a boiler provided in the main passage, the boiler being configured to heat a heat medium using the exhaust gas so as to place the heat medium in a hot-water state;
a bypass passage connected to the main passage so as to detour around the boiler;
a regulation valve member configured to regulate a flow rate of the exhaust gas flowing into the boiler;
a heat medium circuit including a hot-water pump, the heat medium circuit being configured to circulate the heat medium that is heated so as to be placed in the hot-water state by the boiler;
a binary electricity generation device including a circulation circuit through which a working medium circulates, the binary electricity generation device being configured to recover thermal energy from the heat medium in the heat medium circuit and generate electricity;
a valve control unit configured to control an opening of the regulation valve member such that a temperature of the exhaust gas passed through the boiler is equal to or higher than a temperature of an acid dew-point of the corrosive component in the exhaust gas;
a temperature sensor configured to detect a temperature of the heat medium that is in the hot-water state;
a pressure sensor configured to detect a pressure of the heat medium that is in the hot-water state; and
a pump control unit configured to increase a rotation speed of the hot-water pump so that the supercooling degree of the heat medium is maintained in a state in which the supercooling degree has a predetermined value or higher.

Assignees

• Kobe Steel Ltd

Inventors

• Takahashi Kazuo

Classifications

• F22B1/18

  the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines · CPC title

• F02G5/02 Primary

  Profiting from waste heat of exhaust gases · CPC title

• F01N5/02

  the devices using heat · CPC title

• F01K23/101

  Regulating means specially adapted therefor (F01K23/105, F01K23/108 take precedence) · CPC title

• F01K13/02

  Controlling, e.g. stopping or starting · CPC title