Removal of liquid from pullulan
AssigneesShin-Etsu Chemical Co., Ltd., Shin-Etsu Bio, Inc.
InventorsKanji Murofushi, Shigehiro Nagura, Jiro Moriya
Life of this patent
Estimating the term…
Abstract
Pullulan is precipitated from an aqueous solution by mixing with a hydrophilic organic solvent incapable of dissolving pullulan. Solid pullulan is then separated from the liquid component of the dispersion by feeding the dispersion into a V-type disk press having a pair of discoid screens arranged so that the distance between them decreases as they are rotated. The pullulan dispersion is pressed by the discoid screens, recovering the liquid component through the screens. The resulting low-liquid-content pullulan continues to rotate together with the screens to an outlet, where it is discharged from the press.
Claims13
A method for the recovery of pullulan, comprising the steps of:
- a) providing a V-type disk press having an inlet, an outlet, and a pair of discoid screens arranged so that the distance therebetween decreases as the screens are rotated;
- b) feeding, to the inlet, a dispersion containing precipitated pullulan;
- c) rotating said screens from said inlet about respective axes of rotation so that the distance between said screens decreases;
- d) pressing said dispersion between said screens during said step of rotating;
- e) squeezing a liquid component of said dispersion through said screens during said step of pressing;
- f) continuing to rotate said screens about said axes after squeezing said liquid component from said dispersion;
- and
- g) discharging a semi-dry cake of pullulan from between said screens at the outlet during step f) by scraping said semi-dry cake of pullulan from said screens by rotating the semi-dry pullulan component past a scraper member, the space between the screens and the scraper being 1 mm or less.
A method for the recovery of pullulan, comprising the steps of:
- a) providing a press having an inlet, an outlet, and a pair of screens facing one another to define a pressing space therebetween.
- b) feeding, to the inlet, a dispersion containing precipitated pullulan;
- c) pressing said screens towards one another to squeeze said dispersion between said screens;
- d) forcing a component of said dispersion through said screens during said step of pressing;
- and
- e) discharging pullulan in the form of a semi-dry cake from between said screens at the outlet upon completion of said step of pressing and discharging by scraping said semi-dry cake of pullulan from said screens by rotating the semi-dry pullulan component past a scraper member, the space between the screens and the scraper being 1 mm or less.
Dependencies are inferred from the claim text.