Patent ID: 7868166
Filing Date: 2011-01-11
Classification: C08B,F42C

Abstract:
1. A process for the continuous conditioning and/or reacting of a polysaccharide material comprising: a) providing a column having a top portion, a bottom portion and an interior, said interior of said column being substantially filled with a column liquid phase L, and said column having a column liquid phase level; b) introducing continuously a suspension feed stream, comprising a solids phase SE and a liquid phase LE, into said top portion of said column, said suspension feed stream being optionally preheated to a temperature up to 185° C., said column being optionally under a pressure buffer of up to 6 ×10 wherein said solids phase SE is a polysaccharide material selected from the group consisting of cellulose, starch, carboxymethyl cellulose, nitrocellulose, methylcellulose, methylhydroxyalkylcellulose, carboxymethyl starch, and combinations of any of these, and said liquid phase LE is a suspension medium for said solids phase SE, said liquid phase LE comprising water and optionally isopropanol; c) allowing the solids phase SE to sediment freely, due to the action of gravity, through the column liquid phase L to the bottom portion of said column, with the solids phase SE being converted to a solids phase SA by contact at said solids phase SE with the column liquid phase L; d) discharging from the top portion of said column ascending gases G that are optionally formed within said interior of said column; and e) without centrifuging, discharging continuously the solids SA together with a bottoms liquid phase LR and/or LN as a suspension stream at the column bottom at a constant column filling level by adding liquid phase LR previously taken off at the column top and transporting it separately to the column bottom and/or by a liquid phase LN, newly added from outside to the column bottom.