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Title: Effect of Ash in Paper Sludge on Enzymatic Hydrolysis

Journal Article · · Biomass and Bioenergy

The valorization of paper sludge is a high-potential process to develop renewable fuels and chemicals, which can be integrated with pulp and paper mills. Calcium carbonate is the main ash component in sludge, which plays a role in buffering pH and potentially lowering the conversion during enzymatic hydrolysis. Therefore, it is important to investigate the effect of ash on sugar yields and examine pH change to introduce efficient and economical enzymatic hydrolysis of sludge. Carbohydrate conversion was enhanced when the ash was removed by fractionation. On the other hand, the highest sugar recovery was obtained when the sludge contained 20% ash content. The pH change during enzymatic hydrolysis was influenced by ash and explained why sludge-derived hydrolysate showed lower carbohydrate conversion. Therefore, a high shear process with the increased acid amount is suggested to prohibit the negative effect of ash and enhance the accessibility of cellulase to fibers. This study highlights the feasibility of using wet waste streams generated by the paper industry.

Research Organization:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Sustainable Transportation Office. Bioenergy Technologies Office
DOE Contract Number:
AC36-08GO28308
OSTI ID:
1888781
Report Number(s):
NREL/JA-2800-84061; MainId:84834; UUID:eac1b7fd-ed98-4e86-8d0d-440441f4b527; MainAdminID:67532
Journal Information:
Biomass and Bioenergy, Vol. 165
Country of Publication:
United States
Language:
English

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