US4357172A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for continuous crystallization of alpha monohydrate dextrose utilizing high agitation
Assignee: Unilever Bestfoods North America
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Filing: 1980-12-17
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Granted: 1982-11-02
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Expires: 2000-12-17
Abstract
Abstract A process for continuously crystallizing alpha monohydrate dextrose from dextrose-containing liquours. The process is operated isothermally and produces a lean phase massecuite. According to the process, a rate of agitation is employed, within a reaction zone operated in a continuous mode, which permits linear growth of crystals to occur at a growth rate which is surface reaction controlled. The process may be combined with a batch process by feeding lean phase massecuite from the process into a second reaction zone operated in a batch mode. This is done at a constantly declining temperature and produces a rich phase massecuite. The batch process stage is also continuously agitated, but at a slower rate than the first stage continuous process to prevent excessive attrition of existing crystals while maximizing crystal yield.
Inventors
- 👤 Larry W. Edwards
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:05
CPC Classifications
C; C13; C13K; C13K1/00; C13K1/10; C07; C07H; C07H3/00; C07H3/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
200 words
A process for continuously crystallizing alpha monohydrate dextrose from a dextrose containing liquor wherein the primary mode of nucleation is secondary which comprises: continuously introducing a dextrose-containing feed liquor at a predetermined rate into a first reaction zone comprised substantially of a lean phase massecuite having a crystal phase content between about 15% and about 45% alpha monohydrate dextrose; continuously agitating said first reaction zone at an impeller tip speed rate of from about 60 cm/sec to about 600 cm/sec, said rate being characterized high enough to promote good mixing of the feed liquor with said lean phase massecuite within said first reaction zone and to assure a linear crystal growth rate which is surface reaction controlled and low enough to avoid excessive attrition of said lean phase massecuite within said first reaction zone; continuously crystallizing said feed liquor within said first reaction zone to form additional lean phase massecuite, said first reaction zone operating at a constant temperature between about 40° C. and about 50° C., the mean residence time of said feed liquor in said first reaction zone being from about 6 hours to about 30 hours; and continuously withdrawing lean phase massecuite from said first reaction zone.
Claim 2
Dependent Claim
200 words
A process for continuously crystallizing alpha monohydrate dextrose from a dextrose containing liquor wherein the primary mode of nucleation is secondary which comprises: continuously introducing a dextrose-containing feed liquor at a predetermined rate into a first reaction zone comprised substantially of a lean phase massecuite having a crystal phase content between about 15% and about 45% alpha monohydrate dextrose; continuously agitating said first reaction zone at an impeller tip speed rate of from about 60 cm/sec to about 600 cm/sec, said rate being characterized high enough to promote good mixing of the feed liquor with said lean phase massecuite within said first reaction zone and to assure a linear crystal growth rate which is surface reaction controlled and low enough to avoid excessive attrition of said lean phase massecuite within said first reaction zone; continuously crystallizing said feed liquor within said first reaction zone to form additional lean phase massecuite, said first reaction zone operating at a constant temperature between about 40° C. and about 50° C., the mean residence time of said feed liquor in said first reaction zone being from about 6 hours to about 30 hours; and continuously withdrawing lean phase massecuite from said first reaction zone.
Claim 3
Dependent Claim
26 words
A process as defined in claim 1 further including the step of separating a dry sugar and a mother liquor stream from said lean phase massecuite.
Claim 4
Dependent Claim
151 words
A process as defined in claim 1 further including the steps of: immediately introducing said lean phase massecuite from said first reaction zone into a second reaction zone until said second reaction zone is essentially comprised of said lean phase massecuite; continuously agitating said second reaction zone with cooling coils at a rate at which excessive crystal attrition is avoided while heat is transferred between the coils and the bulk of the massecuite; crystallizing said lean phase massecuite within said second reaction zone at a crystallization temperature from about 35° C. to about 50° C. for a time period sufficient to form a rich phase massecuite having a crystal phase content above about 60% alpha-monohydrate dextrose, the temperature of crystallization being lowered from a preselected initial value to a preselected final value during said time period; and separating alpha-monhydrate dextrose crystals from said rich phase massecuite by removal of mother liquor.
Claim 5
Dependent Claim
25 words
A process as defined in claim 1 wherein said rate of agitation is provided by use of an impeller tip speed of about 60 cm/sec.
Claim 6
Dependent Claim
29 words
A process as defined in claim 1 wherein said rate of agitation is provided by use of an impeller tip speed between about 300 cm/sec and about 600 cm/sec.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-11-01 | 1986-05-03 | 1986-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-01 | 1990-05-03 | 1990-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-01 | 1994-05-03 | 1994-11-02 | $7700.00 | Window Closed / Lapsed |