Coal-Direct Chemical Looping Process with In Situ Sulfur Capture for Energy Generation Using Ca–Cu Oxygen Carriers

Abstract

A novel process scheme for energy production from coal with in situ sulfur capture, known as the coal-direct chemical looping process with sulfur removal (CDCL-SR), is proposed in this study. The proposed process utilizes multimetal oxide comprising the oxides of copper and calcium supported on inert SiC as the oxygen carrier to combust coal and simultaneously produce separate streams of CO2 and SO2, thus eliminating the need for downstream processing units. The computational software ASPEN Plus has been utilized to carry out detailed reactor simulations along with a thorough thermodynamic analysis of the process. The reactor modeling results indicate that the moving bed reducer can effectively convert all the carbon present in coal into CO2 while capturing sulfur in the form of calcium sulfide in the reduced oxygen carrier. The reduced oxygen carrier can in turn be oxidized using steam to produce pure SO2 stream that can be readily utilized. Process simulation results indicate that the proposed CDCL-SR process has thermal and exergy efficiencies of 86 and 51%, respectively, significantly higher than both the conventional pulverized coal Rankine cycle and Fe-based CDCL processes.

Synergistic Chemical Looping Process Coupling Natural Gas Conversion and NOx Purification

“…The NO x reactor, which operates as a fluidized bed, is modeled as a single-stage RGibbs reactor. 33 The regenerator can be operated either as a co-current moving bed or a counter-current moving bed. The co-current moving bed is modeled using a single RGibbs reactor, while the countercurrent moving bed is modeled using a series of five RGibbs reactors.…”

“…The NO x reactor, which operates as a fluidized bed, is modeled as a single-stage RGibbs reactor . The regenerator can be operated either as a co-current moving bed or a counter-current moving bed.…”

Nanoscaled Oxygen Carrier-Driven Chemical Looping for Carbon Neutrality: Opportunities and Challenges

“…While the realm of chemical looping applications extends beyond these aforementioned processes, including hydrogen sulfide abatement and ammonia production, this Account primarily highlights its role in CO 2 utilization. Chemical looping offers several advantages over conventional methods, including inherent product separation, enhanced process flexibility, autothermal characteristics, and simple scalability, positioning it as a promising technology. − Notably, under specific conditions, our chemical looping gasification technique can generate high-quality syngas utilizing CO 2 as a partial substitute to steam, rendering the process CO 2 negative. , …”

Comparative Study on Ni/γ-Al2O3 Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

“…It releases a CO 2 -enriched flue gas that simplifies the capture and separation of CO 2 . 7 Chemical looping technology utilizes a solid material mainly to transport the oxygen from the air to the fuel reactor. 8 It has been proposed in various ways including chemical looping combustion (CLC), chemical looping reforming (CLR), chemical looping gasification (CLG), and chemical looping hydrogen generation (CLHG).…”

“…Chemical looping is one of the promising oxyfuel combustion technologies available, and it has been developed over several years. It releases a CO 2 -enriched flue gas that simplifies the capture and separation of CO 2 . Chemical looping technology utilizes a solid material mainly to transport the oxygen from the air to the fuel reactor .…”