fulltext.study @t Gmail

Development and testing of a novel lab-scale direct steam-injection apparatus to hydrolyse model and saline crop slurries

Paper ID Volume ID Publish Year Pages File Format Full-Text
23919 43482 2012 8 PDF Available
Title
Development and testing of a novel lab-scale direct steam-injection apparatus to hydrolyse model and saline crop slurries
Abstract

In this work, a novel laboratory-scale direct steam-injection apparatus (DSIA) was developed to overcome the main drawback of the conventional batch-driven lab rigs, namely the long time needed to heat fiber slurry from room to reaction temperatures greater than 150 °C. The novel apparatus mainly consisted of three units: (i) a mechanically-stirred bioreactor where saturated steam at 5–30 bar can be injected; (ii) an automatic on–off valve to flash suddenly the reaction medium after a prefixed reaction time; (iii) a cyclone separator to recover the reacted slurry.This system was tested using 0.75 dm3 of an aqueous solution of H2SO4 (0.5%, v/v) enriched with 50 kg m−3 of either commercial particles of Avicel® and Larch xylan or 0.5 mm sieved particles of Tamarix jordanis. Each slurry was heated to about 200 °C by injecting steam at 28 bar for 90 s. The process efficiency was assessed by comparing the dissolution degree of suspended solid (YS), as well as xylose (YX), glucose (YG), and furfural (YF) yields, with those obtained in a conventional steam autoclave at 130 °C for 30 or 60 min. Treatment of T. jordanis particles in DSIA resulted in YS and YG values quite similar to those obtained in the steam autoclave at 130 °C for 60 min, but in a less efficient hemicellulose solubilization. A limited occurrence of pentose degradation products was observed in both equipments, suggesting that hydrolysis predominated over degradation reactions. The susceptibility of the residual solid fractions from DSIA treatment to a conventional 120 h long cellulolytic treatment using an enzyme loading of 5.4 FPU g−1 was markedly higher than that of samples hydrolysed in the steam autoclave, their corresponding glucose yields being equal to 0.94 and 0.22 g per gram of initial cellulose, respectively. Thus, T. jordanis resulted to be a valuable source of sugars for bioethanol production as proved by preliminary tests in the novel lab rig developed here.

► A novel laboratory-scale direct steam-injection apparatus (DSIA) was developed. ► It consisted of a stirred vessel, an automatic on–off valve and a cyclone. ► It was tested with particles of Avicel® and Larch xylan or Tamarix jordanis suspended in diluted H2SO4. ► Similar xylose, glucose, and furfural yields were achieved at 200 °C – 1.5 min, and 130 °C – 60 min. ► The cellulolytic treatment of residual steam-exploded solids yielded 0.94 g of glucose per g of initial cellulose.

Keywords
Steam explosion; Direct steam injection apparatus; Lignocellulosic material; Biomass pretreatment; Saccharification; Tamarix jordanis
First Page Preview
Development and testing of a novel lab-scale direct steam-injection apparatus to hydrolyse model and saline crop slurries
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Journal of Biotechnology - Volume 157, Issue 4, 20 February 2012, Pages 590–597
Authors
, , , , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us