A method for extracting hydrolysate， a batch cooking system and a hydrolysate extracting arrangement

A method for extracting hydrolysate in a batch cooking process for producing pulp， said method comprising the steps of:- providing lignocellulose raw material to a batch cooking vessel;- performing acid hydrolysis of the lignocellulose raw material in the batch cooking vessel;displacing a first part of a hydrolysate from the batch cooking vessel by adding to the batch cooking vessel at least one first displacement liquid comprising recycled hydrolysate from a hydrolysate recirculation tank， wherein said recycled hydrolysate has been transferred to the hydrolysate recirculation tank from the batch cooking vessel during a previous batch cooking process;receiving the first part of the hydrolysate in at least one hydrolysate extraction tank;displacing a second part of the hydrolysate from the batch cooking vessel by adding to the batch cooking vessel at least one second displacement liquid comprising alkaline neutralization liquor; andreceiving the second part of the hydrolysate in a hydrolysate recirculation tank.

一种用于生产纸浆的间歇蒸煮过程中提取水解液的方法，所述方法包括以下步骤：
- 将木质纤维素原料（lignocellulose raw material）投入间歇蒸煮釜（batch cooking vessel）；
- 在该间歇蒸煮釜内对木质纤维素原料进行酸水解（acid hydrolysis）；
- 通过向间歇蒸煮釜中加入至少一种第一置换液，将第一部分水解液从间歇蒸煮釜中驱出，该第一置换液包含来自水解液循环罐（hydrolysate recirculation tank）的循环水解液，其中所述循环水解液是在先前的间歇蒸煮过程中从间歇蒸煮釜转移至水解液循环罐的；
- 将第一部分水解液收集至至少一个水解液提取罐（hydrolysate extraction tank）；
- 通过向间歇蒸煮釜中加入至少一种第二置换液，将第二部分水解液从间歇蒸煮釜中驱出，该第二置换液包含碱性中和液（alkaline neutralization liquor）；
- 将第二部分水解液收集至水解液循环罐。