Digestion of fibre pulp from vegetable raw material including pulp level controls
Abstract
Abstract METHOD AND APPARATUS FOR PRODUCING PULP FROM FINELY COMMINUTED MATERIAL SUCH AS SAWDUST FROM WHICH CORASE AND OTHER NONDESIRABLE PARTICULATE MATTER IS WASHED OUT IN A FLOATION DEVICE THROUGH WHICH AN AQUEOUS CHEMICAL SOLUTION IS CIRCULATED IN CONTACT WITH THE PULP MATERIAL, THE THUS IMPREGNATED PULP BEING SUBSEQUENTLY DEWATERED TO A SOLID CONTENT RANGING BETWEEN 30% TO 50% AND FOLLOWED BY TREATMENT WITH STEAM IN A DIGESTER THROUGH WHICH THE PULP IS PASSED BY GRAVITY AND HAVING A CONTROLLER FOR MAINTAINING THE PULP AT A PREDETERMINED LEVEL ABOVE THE OUTLET OF THE DIGESTER AND A SECOND CONTROLLER FOR MAINTAINING A LAYER OF THE PULP AT A CONTROLLED LEVEL ABOVE THE STREAM INLET TO THE DIGESTER, THE PASSAGE OF THE PULP BEING ARRESTED ADJACENT THE STEMA INLET OF A PREDETERMINED PERIOD OF TIME AND ABOVE THE PREDETERMINED LEVEL OF THE DIGESTED PULP.
Inventors
- 👤 Rolf Bertil Reinhall
Bibliographic Details
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