Chemical heat accumulator

Patent metadata

Field	Value
Publication number	US-8951475-B2
Application number	US-201213433766-A
Country	US
Kind code	B2
Filing date	Mar 29, 2012
Priority date	Mar 31, 2011
Publication date	Feb 10, 2015
Grant date	Feb 10, 2015

Abstract

A chemical heat accumulator includes a receptacle, a first reaction vessel, and a second reaction vessel. The first reaction vessel is hermetically connected to the receptacle and supplied with water from the receptacle. The first reaction vessel contains a chemical compound that causes a hydration reaction with the water from the receptacle to generate water vapor by a heat of reaction, and causes a dehydration reaction by receiving heat. The second reaction vessel is hermetically connected to the first reaction vessel and supplied with the water vapor from the first reaction vessel. The second reaction vessel contains a chemical heat storage material that generates heat by causing a hydration reaction with the water vapor from the first reaction vessel and stores heat through a dehydration reaction caused by receiving heat. The chemical heat storage material is thermally in contact with an object to be heated.

First claim

What is claimed is:

1. A chemical heat accumulator comprising:
a receptacle storing water;
a first reaction vessel being hermetically connected to the receptacle and being supplied with the water from the receptacle, the first reaction vessel containing a chemical compound therein that causes a hydration reaction with the water from the receptacle to generate water vapor by a heat of reaction, and causes a dehydration reaction by receiving heat; and
a second reaction vessel being hermetically connected to the first reaction vessel and being supplied with the water vapor from the first reaction vessel, the second reaction vessel containing a chemical heat storage material that generates heat by causing a hydration reaction with the water vapor from the first reaction vessel and stores heat through a dehydration reaction caused by receiving heat, the chemical heat storage material being thermally in contact with an object to be heated; and
a connection pipe connecting the first reaction vessel and the second reaction vessel to supply the water vapor from the first reaction vessel to the second reaction vessel; wherein
the second reaction vessel is one of a pair of second reaction vessels, and
the connection pipe connects the first reaction vessel to each of the pair of second reaction vessels,
the chemical heat accumulator further comprising
an on-off valve disposed on the connection pipe.

2. The chemical heat accumulator according to claim 1 , further comprising:
a control unit configured to control the on-off valve to adjust at least one of an amount of the water vapor supplied from the first reaction vessel to each of the second reaction vessels and a timing to supply the water vapor from the first reaction vessel to each of the second reaction vessels.

3. The chemical heat accumulator according to claim 2 , wherein
the pair of second reaction vessels is disposed in an exhaust pipe through which an exhaust gas from an engine flows such that one of the second reaction vessels is located upstream of the other with respect to a flow of the exhaust gas, the one being an upstream second reaction vessel and the other being a downstream second reaction vessel,
the first reaction vessel is disposed in the exhaust pipe downstream of the downstream second reaction vessel with respect to the flow of the exhaust gas,
each of the upstream and downstream second reaction vessels provides a gas passage therein to allow the exhaust gas to flow and supports the object to be heated in the gas passage, the object to be heated being a catalyst for purifying the exhaust gas, and
the control unit controls the on-off valve so that the water vapor is supplied from the first reaction vessel to the upstream second reaction vessel in an initial stage when the engine is started, and controls the on-off valve so that the water vapor is supplied from the first reaction vessel to the upstream second reaction vessel and the downstream second reaction vessel when a temperature of the chemical heat storage material of each of the upstream second reaction vessel and the downstream second reaction vessel is lower than an equilibrium temperature of the chemical heat storage material after the initial stage.

4. The chemical heat accumulator according to claim 2 , further comprising:
an operation state detector configured to detect a discharge pressure and a rotational speed of the engine, wherein
the control unit controls the on-off valve so that the water vapor is supplied from the first reaction vessel to one of the second reaction vessels when it is determined that the engine is in a partial load state based on a detection result of the operation state detector, and controls the on-off valve so that the water vapor is supplied from the first reaction vessel to each of the second reaction vessels until a temperature of the chemical heat storage material of the respective second reaction vessel reaches an equilibrium temperature of the chemical heat storage material when it is determined that the engine is in a full load state based on the detection result.

5. The chemical heat accumulator according to claim 1 , wherein
the first reaction vessel is disposed in an exhaust pipe through which an exhaust gas from an engine flows, and
the first reaction vessel provides a gas passage therein to allow the exhaust gas to flow, and supports a catalyst in the gas passage for purifying the exhaust gas.

6. The chemical heat accumulator according to claim 1 , further comprising:
a condenser being hermetically connected to at least one of the first reaction vessel and the second reaction vessel, wherein
the condenser is configured to receive the water vapor generated by the dehydration reaction from the one, to condense the water vapor therein to generate water, and to supply the water to the receptacle.

7. The chemical heat accumulator according to claim 1 , wherein the second reaction vessel is separate from the first reaction vessel.

8. The chemical heat accumulator according to claim 7 , further comprising a condenser disposed between the second reaction vessel and the receptacle storing water.

9. A chemical heat accumulator comprising:
a receptacle storing water;
a first reaction vessel being hermetically connected to the receptacle and being supplied with the water from the receptacle, the first reaction vessel containing a chemical compound therein that causes a hydration reaction with the water from the receptacle to generate water vapor by a heat of reaction, and causes a dehydration reaction by receiving heat; and
a second reaction vessel being hermetically connected to the first reaction vessel and being supplied with the water vapor from the first reaction vessel, the second reaction vessel containing a chemical heat storage material that generates heat by causing a hydration reaction with the water vapor from the first reaction vessel and stores heat through a dehydration reaction caused by receiving heat, the chemical heat storage material being thermally in contact with an object to be heated;
a connection pipe connecting the first reaction vessel and the second reaction vessel to supply the water vapor from the first reaction vessel to the second reaction vessel;
a condenser, wherein
the connection pipe respectively connects the first reaction vessel, the second reaction vessel and the condenser,
the chemical heat accumulator further comprising
an on-off valve being disposed on the pipe, the on-off valve being switched between a first state where the first reaction vessel is communicated with the second reaction vessel and a second state where the first reaction vessel is communicated with the condenser and the second reaction vessel is communicated with the condenser; and
a control unit being configured to switch the on-off valve to the first state when the hydration reaction is carried out in the first reaction vessel and the second reaction vessel, and to the second state when the dehydration reaction is carried out in the first reaction vessel and the second reaction vessel.

10. A chemical heat accumulator comprising:
a receptacle storing water;
a first reaction vessel being hermetically connected to the receptacle and being supplied with the water from the receptacle, the first reaction vessel containing a chemical compound therein that causes a hydration reaction with the water from the receptacle to generate water vapor by a heat of reaction, and causes a dehydration reaction by receiving heat; and
a second reaction vessel being hermetically connected to the first reaction vessel and being supplied with the water vapor from the first reaction vessel, the second reaction vessel containing a chemical heat storage

Assignees

• Komaki Katsuya
• Mieda Hiroshi
• Nakagawa Tadahiro
• Shimazu Takashi
• Wakasugi Tomohisa
• Mitsui Hiroyuki
• Sobukawa Hideo
• Denso Corp

Inventors

• Komaki Katsuya
• Mieda Hiroshi
• Nakagawa Tadahiro
• Shimazu Takashi
• Wakasugi Tomohisa
• Mitsui Hiroyuki
• Sobukawa Hideo

Classifications

• Y02E60/14

  Thermal energy storage · CPC title

• F28D20/003 Primary

  using thermochemical reactions · CPC title

• Y02E60/142

  Cross-Sectional Technologies · mapped topic