Back to results
US 4,289,875 AGranted
Process for continuous filtration and aging of xanthated alkali cellulose
AssigneeFiber Associates, Inc.
InventorsCharles J. Geyer, Jr., Ben E. White
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeFiber Associates, Inc.
InventorsCharles J. Geyer, Jr., Ben E. White
Estimating the term…
A process for the continuous filtration and aging of a viscose solution comprising xanthated alkali cellulose (XAC) is described wherein the XAC is continuously passed in a downstream direction through a series of aging tanks and a series of filter means. The aging tanks are so designed and arranged that the viscose solution is never partitioned into batches, as necessitated by common manufacturing systems, but constitutes a continuous, uninterrupted stream throughout aging filtration, deaeration and spinning. The filter means, standard plate and frame filters, are designed and installed in such a manner that the number of filter changes, or redressings, are substantially reduced in the aggregate, without increasing the number of filters now used in a standard plant, or sacrificing viscose quality. This results in less process interruption, loss of product, and less potential environmental pollution.
An improved continuous process for forming cellulose products by the viscose process from a solution of xanthated alkali cellulose, wherein said solution of xanthated alkali cellulose is passed in a downstream direction through a series of filter means, the improvement comprising controlling the rate of flow per unit area whereby each said filter means in said series has a successively greater initial pressure differential as said xanthated alkali cellulose solution passes in said downstream direction through said series of filter means, so that the filter rate is inversely related to the degree of gel removal.
Dependencies are inferred from the claim text.