Characterization of a mesophilic moderately acidiphilic methanogen from pulp and paper waste treatment system

Peer reviewed: YesNRC publication: Ye

Anaerobic digestion of kraft mill primary sludge

Many kraft mills have a settling basin instead of a clarifier ahead of a mechanically aerated secondary treatment lagoon, to remove the suspended solids from their wastewater. Maintenance of good overall operating efficiency in a settling basin normally requires that an annual mechanical dredging be carried out to physically remove the accumulated sludge, with subsequent disposal of the air dried material to landfill. The overall process is both time consuming and expensive. A field trial has been successfully completed at the kraft mill in Espanola, Ontario which removed the accumulated cellulosic sludge from a 4.5 x 10 4 m3 capacity settling basin by an in situ anaerobic fermentation method we developed and optimized. During the fermentation, the cellulose fibres in the sludge were biodegraded and converted into soluble organic acids, methane and carbon dioxide. The anaerobic digestion process was significantly more economical than the traditional landfill method, and it did not adversely affect the environment or the mill's normal operation.Peer reviewed: YesNRC publication: Ye

EVALUATION OF SUGARCANE BAGASSE ACID HYDROLYZATE TREATMENTS FOR XYLITOL PRODUCTION

Acid sugarcane bagasse hydrolyzate was submitted to pH shifts in order to remove toxic compounds from the medium. The hydrolyzate was treated with bases containing mono-, di- or tri-valent cations and H2SO4, and its performance as a fermentation medium was evaluated by the production of xylitol by Candida guilliermondii FTI 20037. The use of bases containing mono-valent cations was not an efficient method of detoxification, and the use of a tri-valent cation did not show any detectable improvement in detoxification. The treated hydrolyzate recovery (in volume) is greatly affected by the utilized base. Treatment using Al(OH)3 and NaOH showed the best hydrolyzate recovery (87.5%), while the others presented a recovery of about 45% of the original hydrolyzate volume. Considering the whole process, best results were achieved by treatment using Al(OH)3 and NaOH which allowed 0.55 g of xylitol produced from each gram of xylose in the raw hydrolyzate

Outcomes of allogeneic haematopoietic stem cell transplantation from HLA-matched and alternative donors: a European Society for Blood and Marrow Transplantation registry retrospective analysis

Transplantation and immunomodulatio