Degradation of amine-based solvents
- Authors: Reynolds, Alicia , Verheyen, Vincent , Meuleman, Erik
- Date: 2016
- Type: Text , Book chapter
- Relation: Absorption-Based Post-Combustion Capture of Carbon Dioxide Chapter 16 p. 399-423
- Full Text: false
- Reviewed:
- Description: Degradation of aqueous amines during post-combustion capture (PCC) of CO2 from fossil-fuel flue gases by wet gas scrubbing can lead to reduced energy efficiency, operational instability, increased corrosion, and unwanted emissions to the environment. Oxidative amine degradation and the accumulation of heat-stable salts primarily occur during absorption of CO2, whereas carbamate polymerization (also called thermal degradation) primarily occurs during desorption of CO2 and thermal amine reclamation. Oxidative degradation is closely related to corrosion, catalyzed by dissolved metal ions, and can be exacerbated by intermittent operation of PCC. Other important reactions, such as nitrosation, occur at much slower rates but can produce environmentally sensitive compounds. The ability to measure the concentrations of individual compounds or monitor amine degradation during PCC is important for managing amine degradation during PCC and demonstrating compliance with environmental regulations. Although some suitable analytical methods are available, further work is needed before they could satisfy the rigorous statutory and legal requirements. Strategies for avoiding and managing amine degradation need to be integrated into all PCC activities including: selecting degradation-resistant amines, ensuring adequate pretreatment of CO2-rich flue gas, avoiding severe CO2 absorption and desorption conditions, and the use of anticorrosion and antioxidation additives. Avoiding intermittent operation of PCC processes and choosing nonmetal column packing may also assist in minimizing amine degradation. © 2016 Elsevier Ltd All rights reserved.
Dynamic operation of liquid absorbent-based post-combustion CO2 capture plants
- Authors: Bui, Mai , Gunawan, Indra , Verheyen, Vincent , Meuleman, Erik
- Date: 2016
- Type: Text , Book chapter
- Relation: Absorption-Based Post-Combustion Capture of Carbon Dioxide (Woodhead Publishing Series in Energy) Chapter 24 p. 589-621
- Full Text: false
- Reviewed:
- Description: Dynamic (or flexible) operation has been proposed as a strategy to reduce the impact of integrating post-combustion CO2 capture (PCC) into power plants. It provides a means for counteracting ongoing variations in the composition of flue gas and absorbent, and also accounts for dynamic variations in carbon and electricity pricing, and electricity demand. For example, in periods of low energy demand, electricity prices will be lower and capture rates may be ramped up accordingly. During high-demand periods, electricity prices will be higher, and capture may be turned down or switched off completely. Flexible PCC operation can also coordinate the balance between electricity demand and legislative requirements for CO2 emission reductions, to improve the economic feasibility of PCC. However, dynamic PCC operation imposes process disturbances when the CO2 capture plant is ramped up or turned down. The immediate and long-term effects of these disturbances are unclear. Thus, recent research is now focusing on the feasibility of flexible PCC operation on a technical basis. Dynamic modeling and pilot plant studies will improve our understanding of dynamic PCC behavior and enable process control to be optimized. © 2016 Elsevier Ltd All rights reserved.
Treatment of flue-gas impurities for liquid absorbent-based post-combustion CO2 capture processes
- Authors: Meuleman, Erik , Cottrell, Aaron , Ghayur, Adeel
- Date: 2016
- Type: Text , Book chapter
- Relation: Absorption-Based Post-Combustion Capture of Carbon Dioxide Chapter 22 p. 519-551
- Full Text:
- Reviewed:
- Description: This chapter discusses the importance of flue-gas treatment and the effect of its impurities on post-combustion CO2 capture (PCC) process performance. Important consequences of nonoptimized flue-gas treatment include atmospheric emissions, amine degradation, extra maintenance requirements through corrosion or fly ash deposition, and waste handling. Each of these areas is strongly dependent on the others. We briefly describe existing flue-gas separation technologies and compare them to the requirements of PCC. Further pretreatment technologies are suggested to improve the composition and thereby the properties of the flue gas entering the PCC plant. For optimal plant operation, the overall process from boiler to atmosphere and waste needs to be analyzed holistically, because: certain approaches can increase efficiency when treating multiple contaminants compared with treating each component separately;most "cleaning" steps influence or generate other compounds that could reduce the performance of the process chain;all costs associated with the treatment chain increase production costs, with little or no increase in value. © 2016 Copyright © 2016 Elsevier Ltd All rights reserved.