Abstract
Pretreatment is a key step for lignocellulose converting into universal raw material for industries as alternative of petroleum. This review discusses that single pretreatment lacks cost-competitiveness because only one product takes responsibility for all cost. Based on the inheterogeneity of lignocellulose and the advantages of steam explosion pretreatment, steam explosion integrated pretreatment is proposed as strategy to solve the problem above. Steam explosion integrates with different pretreatment technologies to deconstruct lignocelluloses selectively for multiple products. By comparison, steam explosion-washing-alkali extraction-mechanical carding integrated pretreatment is considered the best. Finally, industrial demonstration of this integrated pretreatment is given out. With this integrated process, the recovery yields of cellulose, hemicelluloses and lignin reached 70, 80 and 80%, respectively. Key words: Clean production technology, Lignocellulose, Integrated pretreatment, steam explosion, industrialization.
Highlights
Making the process cost-competitive is critical for the industrialization of lignocellulose refining
Based on the inheterogeneity of lignocellulose and the advantages of steam explosion pretreatment, steam explosion integrated pretreatment is proposed as strategy to solve the problem above
It was found (Chen et al, 2011b) that rice straw pretreated by dilute-acid/steam explosion had a higher xylose yield, a lower level of inhibitor in hydrolysate and a greater degree of enzymatic hydrolysis, which resulted in a 1.5fold increase in the overall sugar yield while compared to acid-catalyzed steam explosion
Summary
Making the process cost-competitive is critical for the industrialization of lignocellulose refining. Before 1990, lignocellulose was only converted to ethanol with single pretreatment technology including chemical, physical and biological methods. Lignocellulose conversion into single product with single pretreatment method could hardly industrialize nowadays because of high feedstock price and strong environmental consciousness. The production from this technology was 1.5 million tons of fodder yeasts and 195 million L of ethanol It proved that integrated pretreatment for multiproduct was the only way for the industrialization of lignocellulose refining. As early as 1986 (Klyosov, 1986), integrated pretreatment for multiproduct was proposed as an effective way to apply lignocellulose which was considered as wastes of large number . Lignocellulose refining technology could hardly been industrialized due to the lack of competitiveness, though related technology has been researched as long as 100 years and the price of petroleum has been rising nowadays. Even biochemicals could not take place of those from petroleum, multiproduct can make the industrialization of lignocelluloses refining beneficial
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
