Enhancing early-stage techno-economic comparative assessment with site-specific factors for decarbonization pathways in carbon-intensive process industry

Development and evaluation of FINEX off-gas capture and utilization processes for sustainable steelmaking industry

The National Carbon Capture Center: Cost-effective test bed for carbon capture R&D

CO2 capture is an important carbon management route to mitigate the greenhouse gas emission in power sector. In recent years, China Huaneng Group (CHNG) has paid more attention on CO2 capture technology development and launched a series of R&D and demonstration projects. In the area of pre-combustion CO2 capture technology, GreenGen project initiated by CHNG is the first integrated gasification combined cycle (IGCC) power plant in China. Located in Tianjin, GreenGen aims at the development, demonstration and promotion of a near-zero emissions power plant. An IGCC plant of 250 MW has successfully passed full-scale trial operation. In the next phase, a pre-combustion CO2 capture unit will be integrated into the system. Pre-combustion process based on coal chemical process has been developed with lower costs successfully. Regarding to post-combustion CO2 capture (PCC), in 2008, CHNG built a 3,000 tpa CO2 capture plant, which was the first CO2 capture demonstration plant in China. In 2009, CHNG launched a PCC project in Shanghai with a capture capacity of 120,000 tpa CO2. Recently, Huaneng Clean Energy Research Institute (CERI) and Powerspan formed a joint venture, Huaneng-CERI-Powerspan (HCP). HCP has completed the technology qualification program to supply carbon capture technology for the CO2 capture Mongstad project. Besides these activities mentioned above, feasibility studies and system design for large scale PCC system, have been undertaken by CERI and its partners from Australia, US and Europe.

Pre-combustion CO2 capture

Coal is an abundantly available source for power generation in India, contributing about 77% in the total electricity generation in the country. India has substantial reserves of low sulphur, low grade (high ash) coal which is expected to continue to be a major energy source for the next few decades. But the coal-based thermal power industry is responsible for significant share of emissions of the industrial sector in India. Combustion of coal leads to emission of carbon dioxide (CO2), a prominent greenhouse gas (GHG) responsible for climate change. Various CO2 mitigation techniques including Carbon Capture and Sequestration (CCS) may be required in future to stabilize the greenhouse gas level in the atmosphere. The quality of coal used for power generation plays a critical role in deciding the need for appropriate emission control technologies, and affects the performance of the plant (plant efficiency, net electricity generation and CO2 emissions) and cost of electricity generation. It would also affect the overall performance and cost of CCS. This study investigates the impact of coal quality while implementing post-combustion carbon capture system and oxy-fuel carbon capture system in the new supercritical coal fired power plants in India. Pre-combustion CO2 capture in IGCC plant using the Indian coal is a challenge, and hence not included as an option in this analysis. This study focuses on post-combustion CO2 capture and oxy-fuel carbon capture system which seems a promising option in Indian context, considering the large existing pulverized coal (PC) fleet that is available in the country and the ease with which it can be retrofitted. Also, there have been large scale post combustion CCS based demonstration projects in Canada and U.S. with more upcoming projects planned globally. The scope of this work however, is limited till CO2 capture and compression and does not take into account technical and economic viability of transportation and long-term storage (T&S) of the captured CO2, due to the lack of reliable data and cost estimates. The Integrated Environmental Control Model (IECM) is used to simulate 500 MWe supercritical pulverized coal (PC) base plant, with and without CO2 capture system (post-combustion capture and oxy-fuel combustion). The performance of these plants is simulated using coals from different parts of the country, each with different composition, calorific value and pricing. In addition to the domestic coal, plants using imported coal are also simulated. Through this study, we wish to investigate the suitability of Indian coal for implementation of CCS in the country while providing a viable roadmap. Finally, we would also carry out uncertainty analysis to discuss how technical, economic and policy parameters would affect the relevance of CCS in India.

Rising climate change ambitions require large-scale clean hydrogen production in the near term. “Blue” hydrogen from conventional steam methane reforming (SMR) with pre-combustion CO2 capture can fulfil this role. This study therefore presents techno-economic assessments of a range of SMR process configurations to minimize hydrogen production costs. Results showed that pre-combustion capture can avoid up to 80% of CO2 emissions cheaply at 35 €/ton, but the final 20% of CO2 capture is much more expensive at a marginal CO2 avoidance cost around 150 €/ton. Thus, post-combustion CO2 capture should be a better solution for avoiding the final 20% of CO2. Furthermore, an advanced heat integration scheme that recovers most of the steam condensation enthalpy before the CO2 capture unit can reduce hydrogen production costs by about 6%. Two hybrid hydrogen production options were also assessed. First, a “blue-green” hydrogen plant that uses clean electricity to heat the reformer achieved similar hydrogen production costs to the pure blue configuration. Second, a “blue-turquoise” configuration that replaces the pre-reformer with molten salt pyrolysis for converting higher hydrocarbons to a pure carbon product can significantly reduce costs if carbon has a similar value to hydrogen. In conclusion, conventional pre-combustion CO2 capture from SMR is confirmed as a good solution for kickstarting the hydrogen economy, and it can be tailored to various market conditions with respect to CO2, electricity, and pure carbon prices.

Chapter 24 - Carbon dioxide as a main source of air pollution: Prospective and current trends to control

Energy and exergy investigation on two improved IGCC power plants with different CO2 capture schemes

CO2 Capture from Sulphur Recovery Unit Tail Gas by Shell Cansolv Technology

Chemical Looping for Pre-combustion and Post-combustion CO2 Capture

Chapter 10 - Application of membrane technology for CO2 capture and separation

Power plants are a major source of CO2 emissions in the environment, which cause global warming; due to this issue, CO2 capture from hydrocarbon fuels is one of the key technology options to reduce greenhouse gases. Pre-combustion capture of CO2 in the combined gas and steam turbine cycle has been investigated in this paper. The first step in the pre-combustion method is to react the fuel with oxygen, which comes from the air separation unit and produces a mixture of hydrogen and carbon monoxide. The CO is converted to CO2 in a water-shift reactor, and a physical absorbent removes the CO2; a hydrogen-rich fuel is produced, which can be burnt in a gas turbine with minimal CO2 emissions. This paper presents a thermodynamic cycle analysis, where pre-combustion CO2 capture is applied in a combined cycle where the main goal is to reduce the CO2 emission into the atmosphere. The main parameters are varied to examine the influence on cycle performance. The cycle performance results for the combined cycle with CH4 as fuel are presented and compared to the combined cycle with precombustion CO2 capture, both with and without Nitrogen injection into the compressor. An exergy analysis is carried out to determine which case has more exergy destruction. The results indicate that at 45 oC the combined cycle efficiency is raised by around 3 % when the pre-combustion CO2 capture without Nitrogen injection into the compressor is used, and the power output has been increased by 29 %. The performance of combined cycle with CO2 capture can be further enhanced by the N2 acquired from the air separation process and injected into the compressor’s middle stage. The results demonstrate a good improvement in the performance; the power output increases by 48 % and efficiency by 4.2 %. However, exergy destruction is increased when the CO2 capture, both with and without N2 injection into the compressor is used. Nevertheless, pre-combustion capture requires large monetary investment for a new-build plant where also the CO2 emission is reduced by 100 %.

2 - Economic comparison of oxy-coal carbon dioxide (CO2) capture and storage (CCS) with pre- and post-combustion CCS

Carbon capture and storage (CCS) represents a key solution to control the global warming reducing carbon dioxide emissions from coal-fired power plants. This study reports a comparative performance assessment of different power generation technologies, including ultrasupercritical (USC) pulverized coal combustion plant with postcombustion CO2 capture, integrated gasification combined cycle (IGCC) with precombustion CO2 capture, and oxy-coal combustion (OCC) unit. These three power plants have been studied considering traditional configuration, without CCS, and a more complex configuration with CO2 capture. These technologies (with and without CCS systems) have been compared from both the technical and economic points of view, considering a reference thermal input of 1000 MW. As for CO2 storage, the sequestration in saline aquifers has been considered. Whereas a conventional (without CCS) coal-fired USC power plant results to be more suitable than IGCC for power generation, IGCC becomes more competitive for CO2-free plants, being the precombustion CO2 capture system less expensive (from the energetic point of view) than the postcombustion one. In this scenario, oxy-coal combustion plant is currently not competitive with USC and IGCC, due to the low industrial experience, which means higher capital and operating costs and a lower plant operating reliability. But in a short-term future, a progressive diffusion of commercial-scale OCC plants will allow a reduction of capital costs and an improvement of the technology, with higher efficiency and reliability. This means that OCC promises to become competitive with USC and also with IGCC.

Amine-based post-combustion CO2 capture in air-blown IGCC systems with cold and hot gas clean-up