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The CO2 concentration of flue gas from a natural-gas-fired power plant is only about 50% of that from a coal-fired plant. In contrast, the O2 concentration is more than double, which makes it more difficult to capture CO2 from the former source. China Huaneng Group, which is the largest power generation company in the world, has demonstrated post-combustion CO2 capture (PCC) in two coal-fired plants at a scale of 3 kt/y and 120 kt/y, and has now developed the capture technology for gas-fired power plants for the first time in China. A 100 kg/h CO2 capture pilot plant from natural-gas-fired flue gas has been built and the technology verification program has been conducted continuously for 4000 h. In this work, a novel PCC system with mechanical vapor recompression (MVR) was introduced, and the secondary pollutants from the absorber, material corrosion, solvent loss, and energy penalty during the verification test were investigated. From the aspect of pollutants control of the tail gas from the absorber, the volatile solvent content is less than 0.17 ppm, and total nitrosamine is less than 3 μg/Nm3. Compared with the traditional regeneration mode of steam, the energy penalty can be reduced by 10%∼15% by using the novel Steam-Flash-MVR system. This indicates that the system and process is technically feasible for CO2 capture from natural gas power plant, the solvent used is robust and reliable in long-time operation with a low corrosion and degradation rate. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Abstract: The COACH project (Cooperation Action Within CCS China-EU 1 [1] EC/FP6 Contract #038966, co-ordinated by F. Kalaydjian, IFP Energies nouvelles, France. ) was launched on November 1st 2006 for a period of 3 years, as part of the 6th framework programme of the European Commission 2 [2] The French Agency for Development (AFD) is gratefully acknowledged for its financial support to the dissemination, knowledge sharing and capacity building activities developed in COACH. . Gathering 20 partners comprising 8 Chinese partners and 12 European partners, the COACH project was conceived as contributing to the first phase of the Near Zero Emission Coal fired power plants (NZEC) programme, a 3-phase programme developed between the European Union and China, aiming at combating climate change by enabling the deployment in China of thermal power plants equipped with capture and storage (CCS) facilities. The objective of the COACH project was to establish the basis for the large-scale use of coal for polygeneration in China with pre-combustion capture, transport and geological storage of CO2. Main efforts were place on a future CCS demonstration operated on an Integrated Gasification Combined Cycle (IGCC) thermal power plant fully equipped for converting and splitting the produced syngas into a hydrogen-rich fuel gas and CO2, and with a subsequent storage of CO2 in either mature hydrocarbon reservoirs (Dagang or Shengli oil provinces), deep saline formations or unmineable coal seams. Focus was made on the emission sources and storage sites located in the part of the Bohai Basin in the Shandong Province. The paper will present the main outcomes of the project as follows : [•] Structuring the China-EU COACH venture: In order to enabling the sharing of knowledge between European and Chinese COACH partners and building capacity a survey of CCS activities was performed, workshops were organised in EU and China, a cooperative website was created and two one-week long CCS schools were organised in China gathering more than 100 students 2/3 thereof coming from China and the remaining from Europe; [•] Technical actions and challenges relating to CCS, gasification and polygeneration: A generic IGCC concept implemented with CO2 capture was defined and compared against a plain IGCC based on the GreenGen Phase I system without CO2 capture. A detailed analysis of technologies needed for implementing an option for CO2 capture in an IGCC process with provision for production of electricity and methanol was carried out as well as a cost analysis of both CO2 capture and transport; [•] Geological assessment and storage sites mapping: A quantitative assessment of the potential storage sites (the Dagang and Shengli oil provinces, the deep saline aquifers nearby and the Kailuan coal mining area) was performed along with a mapping of the possible transport infrastructure (by pipelines or ships) that could be developed to connect CO2 sources to CO2 sites; with regards to storage capacity, the main capacity was found to reside in the deep saline aquifers (several giga tonnes) but would require further geological investigation for delivering definite values. The storage potential in oil fields was found to be much smaller (less than one giga tonne) but could provide opportunities for enhanced oil recovery. Finally, the coals of Kailuan mining area exhibit a high ability to adsorb CO2 and provide enhanced coalbed methane recovery, but their injectivity remains to be verified. [•] Case studies and recommendations for CCS demonstration in China: By integrating results obtained in the previous tasks dealing with CO2 capture and CO2 storage, two scenarios (one small scale–from 0.1 to 1 million tonnes of CO2 per year, one large scale–2 to 3 million tonnes of CO2 per year) were designed to screen options for a possible CCS demonstration project. These alternative CO2 streams are both considered captured from the GreenGen IGCC power plant in Tianjin and transported to one or more geological formations in the Bohai Bay geological basin for permanent disposal. Storage for the smaller scale scenario could be accommodated in the Dagang or Shengli oilfields. Storage for the larger scale scenario (2–3 million tonnes a year) could be accommodated in the Shengli oilfield province (in a number of fields) or potentially in the saline formations that can be found in the Huimin sub-basin area. For each of these options, a preliminary risk assessment was performed. A thorough cost analysis was performed. Policy and regulation issues pertaining to a shift towards CCS in China. The 3-year targeted cooperative actions under the COACH project have mobilised capacities in China and Europe and paved the ground for subsequent CCS demonstrations in China. The next phase of the China-EU NZEC programme should start in 2010 and deliver FEED studies which should allow starting operating a CCS demonstration in China by 2015. [Copyright &y& Elsevier]

Abstract: The first industrial-scale CO2 capture plant in China has been demonstrated at Huaneng Beijing power plant has shown that this technology is a good option for the capture of CO2 produced by commercial coal-fired power plants. The commissioning and industrial tests are introduced in this paper. The tests show that in the early stages of the passivation phase, the concentration variations of amine, anti-oxidant and Fe3+ are in the normal range, and the main parameters achieve the design value. The efficiency of the CO2 capture was about 80–85%, and by the end of January 2009 about 900tons of CO2 (99.7%) have been captured. The equipment investment and consumptive costs, including steam, power, solution and others, have been analyzed. The results show: the cost of the absorber and the stripper account for about 50% of main equipment; the consumptive cost is about 25.3US$ per metric tons of CO2, of which the steam requirement accounts for about 55%; the COE increased by 0.02US$/kWh and the electricity purchase price increased by 29%. [ABSTRACT FROM AUTHOR]

CALF-20 nanocrystals uniformly anchored on the macroporous surface of poly(acrylate) via in situ crystallization technique, forming a carbophilic/hydrophobic functional composite. Scalability supports the successful kilogram-scale production. The composite extends the application scope of CALF-20 from cement kilns to post-combustion high-humidity flue gases due to the rapid CO 2 adsorption kinetic and the blocking effect of the hydrophobic shell on water. [Display omitted] • Nano-ZnC 2 O 4 seeds in the confined space induced inhomogeneous nucleation. • CALF-20 nanocrystals provided high adsorption efficiency and low diffusion barrier. • The composite yielded 2.2 times CO 2 /N 2 dynamic selectivity than that of the powder. • The composite retained 97.1% dry CO 2 uptake at high-humidity simulated flue gas. To extend the application range of Calgary framework-20 (CALF-20, Zn 2 (1,2,4-triazolate) 2 (oxalate)), an in-situ crystallization method was used to synthesize spherical CALF-20@poly(acrylate) composite. Owing to the inhomogeneous nucleation induced by nano-ZnC 2 O 4 in poly(acrylate), the size of CALF-20 was reduced to 100–200 nm, forming a carbophilic/hydrophobic functional composite with a macroporous/microporous coupling structure. Compared with the original powder, the adsorption efficiency of the CALF-20 nanocrystals in poly(acrylate) improved by 32 %. In a penetration experiment (10 vol% CO 2 /90 vol% N 2 and 90 % relative humidity), the composite retained 97.1 % of its dry CO 2 uptake capacity. The dynamic selectivity of CO 2 /N 2 reached 77.5, which was 2.2 times higher than that of the CALF-20 powder. These results demonstrate that CALF-20@poly(acrylate) can be applied to high-humidity flue gases. [ABSTRACT FROM AUTHOR]

The synthesis of structured CO 2 adsorbents with high separation selectivity, strong stability, and low cost to meet industrial needs is very challenging. Here, we synthesized an ultra-stable Zn-MOF (Zn 2 (3-amion-1,2,4-triazolate) 2 (oxalate), Zn 2 (Atz) 2 Ox), and adopted an efficient in-situ growth strategy to produce millimeter-sized spherical Zn 2 (Atz) 2 Ox@AFP (Amino-Functionalization Poly(acrylates), AFP) composite. Due to the heterogeneous crystallization induced by the nanoscale crystal seeds and the confined space of AFP, the three-dimensional (3D) Zn 2 (Atz) 2 Ox bulk crystals transformed into 2D nanosheets with higher CO 2 adsorption efficiency and faster kinetics. Zn 2 (Atz) 2 Ox@AFP has a high affinity for CO 2 (2.05 mmol g−1 at 0.05 bar and 313 K) while exhibiting an inhibitory effect for N 2 (only 0.051 mmol g−1 at 1.0 bar and 313 K), leading to an excellent ideal adsorbed solution theory (IAST) selectivity (2990 for CO 2 /N 2 (5/95, v/v)). Interestingly, Zn 2 (Atz) 2 Ox@AFP exhibits a unique gating effect on CH 4 adsorption, which further extends its application range to natural gas purification. Dynamic breakthrough experiments confirmed that Zn 2 (Atz) 2 Ox@AFP can selectively capture CO 2 in the simulated CO 2 /N 2 (5/95) and CO 2 /CH 4 (5/95) mixed gases. The transformation of 3D micrometer-sized Zn 2 (Atz) 2 Ox crystals into 2D nanosheets was achieved in spherical polyacrylate particles via in-situ crystallization technology and obtained a Zn 2 (Atz) 2 Ox@AFP composite with high moist heat stability. Plentiful CO 2 adsorption site and lower gas diffusion resistance of Zn 2 (Atz) 2 Ox nanosheets enhance the adsorption efficiency, adsorption kinetic, and selectivity, thus extending to low concentration CO 2 capture. [Display omitted] • The 3D bulk MOF crystals transformed into 2D nanosheets in the polymer matrix. • Zn 2 (Atz) 2 Ox nanosheets yielded higher adsorption efficiency than that of its powder. • The composite provided 42% faster CO 2 kinetics than that of its powder. • The composite exhibits both high CO 2 /N 2 and CO 2 /CH 4 separation selectivity. • The composite retained 95.6% CO 2 uptake after soaking in 403 K water for 7 days. [ABSTRACT FROM AUTHOR]

• Regulated proton migration during amine grafting through solvent effects. • Ultra-high amine group utilization of 89.6% at ambient condition is obtained. • With a 27.5-fold adsorption capacity increase of UiO-66(Zr)-based adsorbent using NMP. • Regeneration energy consumption below 2.5 GJ/t CO 2 under a lower humidity is achieved. In recent years, the solid amine of Metal-Organic Frameworks (MOFs) has shown promise as a direct air capture (DAC) adsorbent. However, the efficiency of amine groups under ultra-low CO 2 concentrations requires improvement. In this study, we propose a novel method to regulate proton migration through solvent effects during amine grafting, to enhance the synthesis of MOFs as solid amine adsorbents and improve amine group utilization. This approach yielded outstanding results with a MIL-100(Cr)-based DAC adsorbent, demonstrating a CO 2 adsorption capacity of 2.15 mmol/g and an ultra-high amine group utilization of 89.6 % at ambient conditions. By directional deprotonation regulation, the CO 2 adsorption performance of the UiO-66(Zr)-based adsorbent significantly increased from 0.06 mmol/g of using H 2 O as solvent to 1.71 mmol/g of using NMP, with a 27.5-fold increase. Specifically, organic polar aprotic solvents enhanced the binding energy and reduced the energy barrier for deprotonation during the grafting process, thereby improving CO 2 adsorption performance and amine group utilization, which shed a new light on the development of MOFs based CO 2 adsorbent. Furthermore, due to the coordination of secondary amine groups with metal sites leads to the decrease of hydrophilic functional groups in the CO 2 adsorption products, the hydrophobicity of products was reduced significantly resulting in an increase in the ΔS of the hydrated ion pairs after the adsorption, which reduced the heat of CO 2 adsorption about 15 % than that reported in the literature. Based on changes in humidity conditions, the regeneration energy consumption of the MF-Cr-AEEA is less than 2.5 GJ/t CO 2 under a relatively lower humidity, demonstrating outstanding industrial applications potential of the adsorbent. [ABSTRACT FROM AUTHOR]