Akzo Nobel N.v.

Eka Chemicals Ab

Akzo Nobel Pulp and Performance Chemicals Ab

Patrick S Bryant

John Charles Sokol

Jiri J Basta

Michael Burke

Gary Charles

Daniel D Olson

Dwane S Hutto

Donald Fitzgerald Moles

Gary A Charles

The invention relates to a continuous process for producing chlorine dioxide comprising the steps of continuously:

Chemical process and production unit

The present invention relates to a process for the removal of lignin from lignocellulose containing material comprising treating the lignocellulose containing material prior to a high-yield pulping process with a delignifying gas comprising gaseous compounds comprising at least one oxygen atom such as chlorine dioxide containing gas.

Process for removal of lignin from lignocellulosic material

The present invention relates to a process for the removal of lignin from lignocellulose containing material comprising treating the lignocellulose containing material prior to a chemical pulping process with a delignifying gas, wherein the gas comprises chlorine dioxide.

Process for gas phase pretreating of lignocellulosic containing material

The process according to the present invention relates to the treatment of wastewater discharged from a bleach plant and more particularly treatment of bleach plant alkaline wash filtrate from treatment-steps and/or delignification/bleaching-steps of pulp. Further improvements of known processes are needed for solving the problems associated with the recovery of alkaline filtrates into the chemical recovery system. According to the process of the present invention, alkaline wash filtrate from treatment-steps and/or delignification/bleaching-steps of pulp is treated in a process by the following steps: i) treating at least a part of the alkaline filtrate in order to produce an alkaline concentrate enriched in high molecular weight dissolved organic compounds and a stream depleted in organic compounds, where the share of the alkaline concentrate to the total amount of the alkaline filtrate corresponds to a volume reduction factor (VRP) in the range of from about 2.0 up to about 7.5; ii) withdrawing the depleted stream; iii) collecting at least a part of the alkaline concentrate from step i) and using the concentrate as wash or dilution water in brownstock washing fiberline with a dilution factor of up to about 4.0, where at least a part of the washing filtrate is brought to the chemical recovery system.

Process for treating wastewater from a bleach plant

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Woodstock, GA, United States of America

Patrick S Bryant