Parametric study and exergy analysis of the gasification of sugarcane bagasse in a pressurized circulating fluidized bed
- PDF / 1,641,755 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 11 Downloads / 178 Views
Parametric study and exergy analysis of the gasification of sugarcane bagasse in a pressurized circulating fluidized bed gasifier Abinash Mahapatro1 · Alok Kumar2 · Pinakeswar Mahanta1,2 Received: 23 October 2019 / Accepted: 22 July 2020 © Akadémiai Kiadó, Budapest, Hungary 2020
Abstract The present work is to study the effect of pressure on the gasification of sugarcane bagasse in a pressurized circulating fluidized bed reactor. The range of operating pressure is maintained at 1–4 bar, and thereby the composition of generated syngas is measured with the help of gas chromatography. The gasification parameters like dry gas yield, lower heating value (LHV), cold gas efficiency (CGE), and carbon conversion efficiency (CCE) have been calculated from the syngas composition. The output yields some interesting results, i.e., with the increase in pressure from 1 to 4 bar, and there is an increment of concen O2. However, a decreasing trend of H 2 concentration (7.62–6.75% by volume) is tration value by 26% for C H4 as well as C observed for the same pressure rise. In addition, it has been observed a little deviation in the trend for CO (16.39–16.86%), which bears an increasing trend from a pressure of 1–2 bar and a decreasing trend thereafter. Following a similar trend for CO, the LHV first increases from 4013 to 4200 kJ Nm−3 with an increase in pressure from 1 to 2 bar and thereafter decreases gradually to 4081 kJ Nm−3 at a pressure of 4 bar. Apart from these parameters, gas yield, CCE, and CGE values imparted positive effects with pressure rise, and the magnitudes increased from 0.93 to 1.27 Nm3 kg−1, 38.3–57.5 and 23.3–32.3%, respectively, with an increase in pressure from 1 to 4 bar. The exergy destruction and exergy efficiency are observed to be 140 MW and 76% at 4 bar operating pressure. Keywords Gasification · Sugarcane bagasse · Exergy analysis · PCFB (pressurized circulating fluidized bed) List of symbols H2 Concentration of hydrogen in the syngas N2 Concentration of nitrogen in the syngas C Content of carbon in the feed material CO Concentration of carbon monoxide in the syngas CO2 Concentration of carbon dioxide in the syngas CH4 Concentration of methane in the syngas CmHn Concentration of higher hydrocarbon in the syngas cp Constant pressure specific heat capacity (kJ kmol−1 K−1) ER Equivalence ratio h Specific enthalpy (kJ kmol−1)
Xash Ash content of the feed material Y Dry gas yield (Nm3 kg−1) Qa Mass flow rate of air (Nm3 h−1) Mb Mass flow rate of feed material (kg h−1) LHV Lower heating value (kJ Nm−3) HHV Higher heating value (kJ Nm−3) ̇ Energy rate (MW) En ̇ feed material Exergy of feed material Ex ̇ air Exergy of the fluidization air Ex ̇ heat input Exergy of the electrical heat input Ex ̇ Syngas Exergy of the syngas Ex ̇ Char Exergy of the char Ex ̇ tar Exergy of the tar Ex ̇Igasifier Irreversibility of the gasifier β Quality of feed material
* Abinash Mahapatro [email protected]; [email protected]
Introduction
1
Department of Mechanical Engineer
Data Loading...
