Research Colloquium for Mr. Tirupathi Naidu Chintala (CH16D013)

Research Colloquium for Mr. Tirupathi Naidu Chintala (CH16D013)

When:
December 26, 2022 @ 3:00 pm – 4:00 pm
2022-12-26T15:00:00+05:30
2022-12-26T16:00:00+05:30
Where:
Online
Contact:
Head's Office
044-22574150

Name: Mr. Tirupathi Naidu Chintala (CH16D013)

Title: Thermodynamic Analysis of Optimal Performance of Gasification and Chemical Looping Gasification

Abstract:

Gasification is a process of converting any carbonaceous feedstock into syngas by employing blend of gasification agents O2, steam and or CO2. The equilibrium modeling of gasification provides quick limits of syngas characteristics (syngas composition, carbon conversion and cold gas efficiency (CGE)). The existing literature on equilibrium modelling of gasification has mostly focused on single feed and single gasification agent. In this work, unified model applicable for any feedstock and blend of gasification agent, is proposed to predict the gasification performance under isothermal and adiabatic conditions and the model is validated with Aspen plus.

The oxygen required for gasification requires costly air separation unit (ASU). To avoid utilization of ASU, a novel method called chemical looping gasification (CLG) is adopted to generate syngas. CLG employs a solid oxygen carrier (OC) like metal oxides instead of molecular oxygen. In this work, thermodynamic modeling of chemical looping gasification (CLG) process is carried out using the Gibbs free energy minimization approach. The effect of temperature, Fe2O3/C, steam/C and CO2/C on syngas characteristics and solids composition are analyzed in detail and the optimum performance of CLG for feedstocks of different H/C and O/C is presented as contour plots.

One of the crucial advantages of CLG is that the plant can be operated auto thermally (aCLG) due to energy integration between the fuel reactor (FR) and air reactor (AR). In this work, studies on aCLG have been carried out by solving mass and energy balance equations along with equilibrium relation. The effect of solids circulation rate on air flow and AR temperature required to attain aCLG condition have been studied in detail. The optimum conditions have been established and generalized analysis on optimal performance of CLG at auto thermal conditions is carried out.

Keywords: Chemical looping gasification, thermodynamic modeling, syngas composition, optimal operation point, cold gas efficiency, solid phase composition, auto thermal operation.