초록 ▼

The present invention provides a wet starch preparation system for gypsum wallboard comprising a loss-in-weight starch feeder, a venturi mixer, a vacuum pick-up unit for supplying the dry starch from the feeder at an adjustable rate to the venturi mixer, a first water pump for supplying water at an

The present invention provides a wet starch preparation system for gypsum wallboard comprising a loss-in-weight starch feeder, a venturi mixer, a vacuum pick-up unit for supplying the dry starch from the feeder at an adjustable rate to the venturi mixer, a first water pump for supplying water at an adjustable rate to the venturi mixer to form a starch pre-dispersion of from about 2% to about 10% by weight starch and a second water pump for supplying gauging water to the starch pre-dispersion, the system equipped with appropriate system controls. The present system provides more efficient use of starch such that the amount of pregelatinized starch is at least about 10% less than a system in which the starch is not pre-dispersed in water prior to the board mixer. The system can be used to make gypsum-containing products including gypsum wallboard having increased board strength and reduced board weight.

대표청구항 ▼

1. A method for preparing a starch pre-dispersion in a gauging water line for the production of gypsum wallboard, comprising: (a) feeding a dry starch at an adjustable rate to a venturi mixer;(b) wetting the starch with water in the venturi mixer to form a starch slurry at a concentration of from ab

1. A method for preparing a starch pre-dispersion in a gauging water line for the production of gypsum wallboard, comprising: (a) feeding a dry starch at an adjustable rate to a venturi mixer;(b) wetting the starch with water in the venturi mixer to form a starch slurry at a concentration of from about 2% to about 10% based on the weight of the starch;(c) delivering the starch slurry from the venturi mixer to the gauging water line outside the venturi mixer to form a starch pre-dispersion in the gauging water line; and(d) delivering the starch pre-dispersion in the gauging water line to a board mixer on a production line. 2. The method of claim 1, further comprising: (e) calculating a starch pre-dispersion delivery rate by means of a slurry output controller. 3. The method of claim 1, further comprising recycling the starch slurry before delivering the slurry to the gauging water line to form a starch pre-dispersion in the gauging water line. 4. The method of claim 1, wherein the starch feeding rate is constant. 5. The method of claim 1, wherein the starch slurry is delivered at a constant rate. 6. The method of claim 1, wherein the starch is pregelatinized corn flour.