A typical Allam cycle operates roughly as follows 1 high temperature and

A typical allam cycle operates roughly as follows 1

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A "typical" Allam cycle operates roughly as follows: 1) high-temperature and pressure sCO2 is expanded through a turbine (producing mechanical work that drives a generator, producing electricity) 2) sCO2 is cooled, water is condensed out, and CO2 equivalent to the burned fuel is removed 3) sCO2 is compressed to high pressure 4) fuel is added to the working fluid stream, combusted, and the cycle repeats The illustrated power generation utilizes a hybrid Allam cycle. The hybrid cycle eliminates requirements for cryogenic air separation, removing direct combustion entirely, while retaining the advantages of integrated carbon capture and a relatively simple cycle. A high-temperature fuel cell (3.02) operating from 500-900C is utilized as the topping cycle. The cell stack (3.02) runs incoming synthesis gas (3.13, 3.15) through the anode side and heated air through the cathode. This prevents dilution of the CO2 working fluid (3.17) by atmospheric nitrogen and an economizer (3.08) transfers heat from the exhaust stream to the incoming air (3.16). The exhausted (oxidized) fuel is mixed with the bulk working fluid (3.17) and run through the typical Allam-cycle steps: expanded (3.10), cooled (3.03), water condensed (3.04), re- compressed (3.11), excess carbon dioxide removed (3.05), and reheated (3.03). In place of direct combustion, a second heat exchanger (3.06) is also utilized in reheating the working fluid. This secondary heat exchanger (3.06) draws from S3 and there is no mixing of the power-cycle’s working fluid with reactants from that process. A chemical looping reaction (3.07) is shown to accommodate the added thermal load, molten metals react with oxygen from air (3.16), then get reduced in S3 (reacting exothermically with carbon) and the process is repeated. In the diagram, the air intake/exhaust for the high-temperature fuel cell (3.02) and the molten-metal-oxide chemical-looping (3.07) utilize a common economizer (3.08). The described power cycle integration allows for high-efficiency, integrated CO2 capture (3.18), water conservation (3.19), and electricity generation (3.09). With reference to FIG. 4 , a conceptual diagram of CO2ZERO’s platform integration is illustrated. Any processes referenced are in no way meant to limit system options. Various hypothetical advanced technologies are outlined in FIGS. 1-3, while simple retrofits of modern industrial infrastructure remain advantageous. Having summarized the basic principles of CO2ZERO: Zero Emissions Reforming Operation , further exploration of specific control systems, feedback, monitoring, various integrated complex stages, and optimization (i.e. machine learning applied to complex systems, identifying adaptive edge-of-chaos meta- stabilities) portend myriad opportunities in disruptive and sustainable systems design. For further information regarding Systems Change, SystemsInnovation.io (no affiliation) offer numerous excellent courses, available on YouTube. Here is one recommended link:
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2.01 Molten Salt Stripping 2.12 Molten Salt + Carbon to S3 2.23 Syngas FIG. 2 CO2ZERO – “X to Liquids” Integration 2.09 Carbon + Syngas from S1 2.10 Molten Salt + Carbon to S2 2.02 Feedstock
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