Experimental Demonstration of a Novel Gas Switching Combustion Reactor for Power Production with Integrated CO₂Capture

Abstract

This paper experimentally demonstrates the feasibility of a novel Gas Switching Combustion (GSC) reactor as an alternative to the traditional Chemical Looping Combustion (CLC) process for power production with integrated CO2 capture. Whereas the CLC process circulates an oxygen carrier material between two fluidized bed reactors where it is exposed to separate fuel and air streams, the GSC concept employs a single dense fluidized bed reactor where the oxygen carrier is periodically exposed to fuel and air streams. A lab-scale GSC reactor was operated autothermally (without any external temperature supply) to continuously convert cold feed gasses into hot product gasses which would be suitable for driving a downstream power cycle. A parametric study was carried out to further investigate the behaviour of the GSC concept. The reactor achieved a high CO2 capture efficiency (97.2%) and purity (98.2%) even without the use of a purging stage between the oxidation and reduction stages. A small amount of carbon deposition (around 1%) had a slight negative effect on the CO2 capture efficiency. Finally, the operation of a cluster of GSC reactors capable of delivering two steady process streams to downstream process equipment was discussed. IntroductionSince the start of the second industrial revolution, fossil fuels have driven the global economy to expand by a factor of 50 (1), leading to a 500% increase in population and an 800% increase in per-capita consumption. Today, 150 years later, the global economy remains totally dependent on fossil fuels, deriving fully 87% (2) of its primary energy consumption from oil, coal and natural gas. Fossil fuel consumption is still rapidly increasing while the use of renewable energy sources (primarily hydroelectricity) still contributes only 8% to the global energy production. All major energy roadmaps (3-6) project this trend to continue up to 2030 and beyond.

Innovative Internally Circulating Reactor Concept for Chemical Looping‐Based CO2 Capture Processes: Hydrodynamic Investigation

“…Design and scale‐up of pressurized dual CFB systems is likely to pose important technical challenges related to the achievement of a large solids circulation rate which must be tightly controlled in order to maintain the species and energy balance between the two reactors. For this reason, several alternative reactor configurations have been proposed to simplify the reactor scale‐up process such as packed‐bed CLC (PBCLC) 16, 17, gas switching combustion (GSC) 18–20, and the rotating reactor 21. However, these process concepts also have some disadvantages such as the dynamic nature of the PBCLC and GSC concepts, thus requiring a large assembly of reactors operating in parallel with outlet streams regulated by a high‐temperature valve system, as well as significant gas leakage challenges for the rotating bed.…”

The evaluation of a methane autothermal chemical looping reforming experiment based on exergy analysis

“…The calculation model of the engineering drawing method is as follows. (19) where E F,tot , E P,tot and E D,other are the total input exergy of the system, the total output exergy of the system, and the total exergy destruction of other devices than the reactor x. By drawing of a curve of E F,tot À E P,tot with respect to E D,other , the researchers found that when E D,other ¼ 0, the intercept of the curve on the y-axis is equal to the endogenous exergy destruction of the reactor x.…”

“…9 According to relevant studies, pressurization has a lot of benets to the CLR process, such as improving the conversion rate of carbon, increasing the combustion efficiency, improving the purity of CO 2 captured and reducing the total capital cost of hydrogen production. [19][20][21] However, the CFBR has obvious disadvantages in pressurization. This is because with the increase of pressure, the efficiency of cyclone separator would decrease, while and the destruction of OC particles would increase.…”

Simulation-Based Design and Economic Evaluation of a Novel Internally Circulating Fluidized Bed Reactor for Power Production with Integrated CO2 Capture

“…Consequently, several alternative CLC configurations have been proposed to overcome the challenges of the pressurized dual CFB CLC system. These include gas switching technologies [7,8], rotating bed reactors [9,10], packed bed chemical looping [11,12], and internally circulating reactors (ICRs) [13][14][15], which will be the focus of the present study.…”