Reclaiming device, reclaiming method, and recovery unit for CO2 or H2S or both

• US 10,471,379 B2
• Filed: 01/07/2015
• Issued: 11/12/2019
• Est. Priority Date: 01/17/2014
• Status: Active Grant

• Current Assignee: Mitsubishi Heavy Industries Engineering, Ltd. (Mitsubishi Heavy Industries, Ltd.)
• Original Assignee: Mitsubishi Heavy Industries Engineering, Ltd. (Mitsubishi Heavy Industries, Ltd.)
• Inventors: Hagimoto, Akiyori, Oishi, Tsuyoshi, Hamada, Tsutomu, Yukumoto, Atsuhiro
• Primary Examiner(s): Orlando, Amber R
• Assistant Examiner(s): Shao, Phillip Y
• Application Number:
  US15/110,829
• Publication Number:
  US 20160375398A1
• Time in Patent Office: 1,770 Days
• Field of Search: None
• CPC Class Codes: B01D 2252/204 Amines
• CPC Class Codes: B01D 2252/20478 Alkanolamines
• CPC Class Codes: B01D 2256/24 Hydrocarbons
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2258/02 Other waste gases
• CPC Class Codes: B01D 2258/0283 Flue gases
• CPC Class Codes: B01D 2311/2619 UV-irradiation
• CPC Class Codes: B01D 2311/2653 Degassing
• CPC Class Codes: B01D 2311/2673 Evaporation
• CPC Class Codes: B01D 53/1425 Regeneration of liquid absorbents
• CPC Class Codes: B01D 53/1462 Removing mixtures of hydrogen sulfide and carbon dioxide
• CPC Class Codes: B01D 53/1493 Selection of liquid materials for use as absorbents
• CPC Class Codes: B01D 61/44 Ion-selective electrodialysis
• CPC Class Codes: B01J 39/04 Processes using organic exchangers
• CPC Class Codes: B01J 41/04 Processes using organic exchangers
• CPC Class Codes: B01J 47/00 Ion-exchange processes in general; Apparatus therefor ion-exchange chromatography processes or apparatus B01D15/08
• CPC Class Codes: B01J 49/00 Regeneration or reactivation of ion-exchangers; Apparatus therefor ion-exchange chromatography processes or apparatus B01D15/08
• CPC Class Codes: B01J 49/50 characterised by the regeneration reagents
• CPC Class Codes: C02F 1/048 Purification of waste water by evaporation
• CPC Class Codes: C02F 1/32 : with ultraviolet light
• CPC Class Codes: C02F 1/325 : Irradiation devices or lamp constructions
• CPC Class Codes: C02F 1/42 : by ion-exchange ion-exchange in general B01J
• CPC Class Codes: C02F 1/4693 : electrodialysis
• CPC Class Codes: C02F 2103/18 : from the purification of gaseous effluents
• CPC Class Codes: C02F 2303/16 : Regeneration of sorbents, filters
• CPC Class Codes: Y02C 20/40 : of CO2

Abstract

An evaporator is provided that separates, from a degraded substance, an absorbent branched off and introduced, a heating section which is interposed on a circulation line L₂₁ that circulates the absorbent introduced into this evaporator, heats the circulating absorbent to obtain gaseous recovery steam containing a vaporized absorbent and CO₂, a concentrate branch line L₂₂ that branches off a part of the absorbent circulating through the circulation line L₂₁ at a bottom of the evaporator from the circulation line L₂₁ as a concentrate, a cooler that is interposed on this concentrate branch line L₂₂ and cools the concentrate, an ionic degraded substance removal section that removes an ionic degraded substance in the cooled concentrate, and a purified absorbent discharge line L₂₃ that reuses the concentrate as a purified absorbent from which the ionic degraded substance is removed.

Claims

1. A reclaiming device comprising:

an evaporator that is configured to introduce a part of an absorbent to recover CO₂ or H₂S in a gas in a closed system recovery unit through an introduction line and separate a degraded substance contained in the absorbent from the absorbent;

a heating section that is provided on a circulation line configured to draw off the absorbent from the evaporator and circulate the absorbent therein, and is configured to heat the circulating absorbent to obtain recovery steam containing an absorbent and CO₂ or H₂S;

a recovery steam discharge line that is configured to discharge the recovery steam from a top side of the evaporator;

a concentrate drawing off line that is drawn off from the circulation line and is configured to supply a concentrate from a bottom side of the evaporator;

a cooler that is interposed on the concentrate drawing off line and is configured to cool the concentrate;

an ionic degraded substance removal section that is configured to remove an ionic degraded substance in the cooled concentrate;

wherein

a concentrated waste water line that is branched off from the concentrated drawing off line and is configured to discharge a concentrated waste water; and

a first on-off valve that is provided between the branched portion of the concentrated waste water line and the cooler on the concentrated drawing off line, wherein

the reclaiming device is configured to concentrate an absorbent containing the degraded substance in the evaporator by closing the first on-off valve to concentrate the degraded substance and discharge the concentrated waste water to the outside through the concentrated waste water line.

2. The reclaiming device according to claim 1, wherein

the ionic degraded substance removal section is an electrodialyser or an ion exchange resin device.

3. The reclaiming device according to claim 2, in the case where the ionic degraded substance removal section is the ion exchange resin device, comprising:

a chemical introduction section that introduces a regenerating chemical to the ion exchange resin device; and

a recirculation line that branches off a resin-regenerated waste liquid obtained by regenerating an ion exchange resin with the introduced chemical from a purified absorbent discharge line and recirculates the resin-regenerated waste liquid to the evaporator side, wherein

the ion exchange resin is regenerated by regenerating the ion exchange resin with a regenerating chemical as well as stopping the introduction and discharge of the absorbent and concentrating the resin-regenerated waste liquid in the evaporator while returning the resin-regenerated waste liquid to the evaporator.

4. The reclaiming device according to claim 1, comprising:

an ultraviolet irradiation section that decomposes a nonionic degraded substance, which is provided downstream of the ionic degraded substance removal section.

5. A recovery unit for CO₂ or H₂S or both, comprising:

an absorber that brings a gas containing CO₂ or H₂S or both into contact with an absorbent and removes CO₂ or H₂S or both;

an absorbent regenerator that regenerates a solution that has absorbed CO₂ or H₂S or both to obtain an absorbent; and

the reclaiming device according to claim 1 which draws off a part of the absorbent regenerated in the absorbent regenerator and removes a coexisting substance in the absorbent, wherein

recovery steam recovered from the reclaiming device is introduced into the regenerator as well as the absorbent regenerated in the absorbent regenerator circulates and is reused in the absorber, wherein

the recovery unit is configured to reuse a purified absorbent from which the ionic degraded substance has been removed in the reclaiming device.