Closed drain recovery system

Patent metadata

Field	Value
Publication number	US-9500360-B2
Application number	US-201214387805-A
Country	US
Kind code	B2
Filing date	Apr 27, 2012
Priority date	Mar 29, 2012
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

To achieve a downsized drain tank without reducing an effective drain recovery rate. A closed drain recovery system includes: a steam boiler ( 2 ); a closed-type drain tank ( 4 ); an air-open-type makeup water tank ( 7 ); a steam introduction line ( 10 ) for introducing a first flush steam within the drain tank ( 4 ) to the makeup water tank ( 7 ); a surplus drain introduction line ( 8 ) for introducing surplus drain to the makeup water tank ( 7 ) from the drain tank ( 4 ); and condensing units ( 33 ) and ( 39 ) provided for the makeup water tank ( 7 ), and configured to condense one or both of the first flush steam and a second flush steam by bringing the one or both of the first flush steam and the second flush steam into contact with the makeup water within the makeup water tank ( 7 ), the second flush steam being generated from the surplus drain.

First claim

The invention claimed is:

1. A closed drain recovery system comprising:
a steam boiler configured to supply steam to a loading apparatus;
a closed-type drain tank for reserving drain discharged from the loading apparatus through a drain return line, and configured to supply the reserved drain to the steam boiler through a drain supply line;
an air-open-type makeup water tank configured to supply makeup water to the drain tank through a makeup water line;
a steam introduction line for introducing a first flush steam within the drain tank to the makeup water tank;
a surplus drain introduction line for introducing surplus drain to the makeup water tank from one of the drain tank and the loading apparatus; and
a condensing unit provided for the makeup water tank, and configured to condense one or both of the first flush steam and a second flush steam by bringing the one or both of the first flush steam and the second flush steam into contact with the makeup water within the makeup water tank, the second flush steam being generated from the surplus drain,
wherein the condensing unit brings the makeup water into contact with the one or both of the first flush steam and the second flush steam while causing the makeup water to be circulated within the makeup water tank.

2. The closed drain recovery system according to claim 1 , wherein
the condensing unit includes mixer means and circulation means,
the mixer means includes:
a sprinkler;
a mixer configured to condense the one or both of the first flush steam and the second flush steam by bringing the one or both of the first flush steam and the second flush steam into contact with the makeup water sprinkled from the sprinkler; and
a water introduction unit configured to introduce the water condensed by the mixer into a liquid phase unit of the makeup water tank, and

the circulation means includes:
a circulation pump; and
a circulation line configured to introduce the makeup water at a bottom of the makeup water tank to the sprinkler.

3. The closed drain recovery system according to claim 2 , wherein
the mixer is provided with a contact heat exchange member for exchanging contact heat between the makeup water and the flush steam.

4. The closed drain recovery system according to claim 1 , comprising:
the steam introduction line; and
the surplus drain introduction line, wherein
the condensing unit is provided for a connecting unit of the makeup water tank with the steam introduction line and the surplus drain introduction line.

5. The closed drain recovery system according to claim 1 , comprising:
a first valve that is openable and closable and provided for the drain return line;
the surplus drain introduction line connected between the drain return line on an upstream side of the first valve and the makeup water tank; and
a second valve that is openable and closable and provided for the surplus drain introduction line, wherein
one of a first open-close state and a second open-close state is selectable, the first open-close state being a state in which the first valve is opened and the second valve is closed, the second open-close state being a state in which the first valve is closed and the second valve is opened, and
the surplus drain is introduced into the makeup water tank in the second open-close state.

6. The closed drain recovery system according to claim 5 , wherein
the condensing unit provided for the surplus drain introduction line includes a steam separator disposed under the contact heat exchange member of the mixer, the steam separator being configured to separate steam by causing surplus drain that has flowed in to be hit against a separating plate.

Assignees

• Akinaga Sohei
• Ookubo Tomohiro
• Kobayashi Tatsuki
• Hatanaka Hiroyuki
• Miura Kogyo Kk

Inventors

• Akinaga Sohei
• Ookubo Tomohiro
• Kobayashi Tatsuki
• Hatanaka Hiroyuki

Classifications

• F22D11/06 Primary

  for returning condensate to boiler · CPC title

• F28B1/02

  using water or other liquid as the cooling medium · CPC title

• F22D1/28

  for direct heat transfer, e.g. by mixing water and steam · CPC title