Method for common digestion of two differently pre-treated fractions of wood chips
Abstract
Abstract A CONTINUOUS DIGESTER IS CHARGED WITH WOOD CHIPS DIVIDED BY SCREENING INTO TWO FRACTIONS, VIZ A LARGER FRACTION OF COARSER PARTICLES AND A SMALLER FRACTION OF FINER PARTICLES. THE FRACTIONS ARE DIGESTED IN COMMON BUT ARE PRE-TREATED DIFFERENTLY. THE PRE-TREATMENT OF THE COARSER FRACTION CONSISTS IN STEAMING AND THOROUGH IMPREGNATION WITH DIGESTING LIQUOR, AND THE PRE-TREATMENT OF THE FINER FRACTION CONSISTS IN MERELY STEAMING OR STEAMING AND IM- PREGNATION DURING A SHORTER TIME. THE TWO FRACTIONS ARE CONVEYED TO THE DIGESTER TOP IN DIFFERENT WAYS, THE COARSER CHIPS BEING SUSPENDED IN CIRCULATING LIQUID, AND THE FINER CHIPS MAY BE BLOWN BY STEAM, PREFERABLY STEAM LATER USED FOR HEATING THE DIGESTER TO DIGESTING TEMPERATURE.
Inventors
- 👤 Johan C F C Richter
Bibliographic Details
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