Process for controlling the supply of delignifying and/or bleaching chemicals in the continuous delignification of lignocellulosic material

A process for controlling the supply of delignifying chemicals in the continuous delignification of lignocellulosic material in a through flow delignification stage, which comprises admixing the lignocellulosic material with delignifying chemicals and flowing the lignocellulosic material under delignifying conditions through the stage while controlling the addition of the delignifying chemicals according to the ratio of the quantity of delignifying chemicals consumed to the quantity of delignifying chemicals originally charged to the delignification, the temperature and the time in a manner to maintain substantially constant the relative consumption of delignifying chemicals at a predetermined time by the lignocellulosic material during flow through the stage.

A continuous flow process for the bleaching of lignocellulosic material, in which there is a throughput of lignocellulosic material through a bleaching stage, with addition of bleaching chemicals at at least one location to the bleaching, which comprises adding bleaching chemicals to the system in an amount so adjusted according to the ratio of the quantity of bleaching chemicals consumed and the quantity of the bleaching chemicals originally charged that the relative consumption of bleaching chemicals is maintained substantially constant.

A process for controlling the supply of bleaching chemicals in the continuous bleaching of cellulose pulp in a through flow bleaching stage, which comprises admixing the cellulose pulp with bleaching chemicals and flowing the cellulose pulp under bleaching conditions through the stage while controlling the addition of the bleaching chemicals according to the ratio of the quantity of bleaching chemicals consumed to the quantity of bleaching chemicals originally charged to the bleaching, the temperature and the time in a manner to maintain substantially constant the relative consumption of bleaching chemicals at a predetermined time by the cellulose pulp during flow through the stage.

A continuous flow process for the pulping of lignocellulosic material, in which there is a throughput of lignocellulosic material through a pulping stage, with addition of pulping chemicals at at least one location to the pulping, which comprises adding pulping chemicals to the system in an amount so adjusted according to the ratio of the quantity of pulping chemicals consumed and the quantity of the pulping chemicals originally charged that the relative consumption of pulping chemicals is maintained substantially constant.

A process for controlling the supply of pulping chemicals in the continuous pulping of lignocellulosic material in a through flow pulping stage, which comprises admixing the lignocellulosic material with pulping chemicals and flowing the lignocellulosic material under pulping conditions through the stage while controlling the addition of the pulping chemicals according to the ratio of the quantity of pulping chemicals consumed to the quantity of pulping chemicals originally charged to the pulping, the temperature and the time in a manner to maintain substantially constant the relative consumption of pulping chemicals at a predetermined time by the lignocellulosic material during flow through the stage.