The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 24, 1990
Filed:
Mar. 20, 1987
Seppo K Kokkonen, Savonlinna, FI;
Harri T Qvintus, Savonlinna, FI;
A. Ahlstrom Corporation, Karhula, FI;
Abstract
The present invention relates to a method and an apparatus for washing pulp according to which method the pulp is supplied onto a movable liquid-pervious support surface (2) to form a substantially continuous layer (7); and washing liquid is supplied to the pulp layer and passed in several successive washing phases through different areas of the layer in such a way that the washing liquid gradually flows in the opposite direction compared with the flow direction of the pulp layer. According to the invention the washing liquid is divided in two or more partial flows which pass alternately through different washing phases in such a way that the washing liquid which in one phase has passed through the pulp layer flows past at least the washing phase preceding it in the flow direction of the pulp layer. The apparatus of the invention preferably comprises a rotating cylinder (1) the casting surface (2) of which serves as the liquid-pervious support surface for the pulp.