Operating conditions-induced changes in product yield and characteristics during thermal-conversion of peanut shell to biochar in relation to economic analysis


Liu R., Liu G., Yousaf B. , Abbas Q.

JOURNAL OF CLEANER PRODUCTION, vol.193, pp.479-490, 2018 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 193
  • Publication Date: 2018
  • Doi Number: 10.1016/j.jclepro.2018.05.034
  • Title of Journal : JOURNAL OF CLEANER PRODUCTION
  • Page Numbers: pp.479-490
  • Keywords: Thermochemical conversion, Peanut shell, Pyrolysis condition, Particle size, Yield optimization, Economic analysis, FIXED-BED PYROLYSIS, RUBBER WOOD SAWDUST, CARPINUS-BETULUS L., SLOW PYROLYSIS, BIO-OIL, BIOMASS PYROLYSIS, PROCESS PARAMETERS, SURFACE-CHEMISTRY, SAFFLOWER SEED, HOLDING TIME

Abstract

The influences of pyrolysis conditions on the products yield distribution and physico-chemical characteristics of biochar derived from peanut shell in a fixed-bed reactor were investigated in this study. The pyrolysis conditions included the pyrolysis temperature (300-700 degrees C), retention time (15-90 min), heating rate (1-10 degrees C min(-1)), gas flow rate (20-200 mL min(-1)) and feedstock particle size (<0.075, 0.075 0.150, 0.150-0.300 and 0.300-2.00 mm). Various analytical techniques were used to characterize the biochar for ultimate and proximate analyses, higher heating value (23.99-30.44 MJ kg(-1)), pH (8.11 -12.89), electrical conductivity (22.78-34.44 mS cm(-1)), surface functional groups (acidic, carboxylic and basic groups), Fourier transform infrared spectroscopy analysis, pore volume (0.055-1.241 cm(3) g(-1)) and specific surface area (7.12-20.96 m(2) g(-1)). The results demonstrated that the temperature predominantly regulated the product yields distribution and characteristics of produced biochar. Furthermore, the heating rate considerably influenced the biochar proximate composition, micropore surface area and pore size. Particle size had significant influences on biochar surface porosity and bio-oil yield. The economic analysis of the pyrolysis system indicated its feasibility and superiority with a positive net present value of 12.07 x 10(6) USD after twenty-five years of operation. (C) 2018 Elsevier Ltd. All rights reserved.