Foam composition
Foams suitable for such uses as landfill coverage, frost protection, volatile emission control, gas control in mining, are composed of a hydrolyzable protein and a pre-gelatinized cationic modified starch along with other ingredients. The foam concentrate can be made at ambient temperature, is stable over time, can be easily tailored to achieve a desired foam stiffness and drain time characteristic over wide ranges, and can be easily diluted at ambient temperature to produce a foamable composition.
1. A method of making a foamable concentrate comprising the steps of adding to water a pre-gelatinized cationic modified starch having a degree of substitution of at least approximately 0.02 and a nitrogen content of at least approximately 0.15%, and a stabilized hydrolyzed protein.
2. The method according to claim 1 , in which, when the pre-gelatinized cationic modified starch is added to the water, the water is at a temperature in the range from approximately 10° C. to 60° C.
3. The method according to claim 1 , in which, when the pre-gelatinized cationic modified starch is added to the water, the water is at a temperature in the range from approximately 15° C. to 30° C.
4. The method according to claim 1 , in which the pre-gelatinized cationic modified starch, when added to the water, has a particle size distribution such that not more than about 25% by weight of the starch would pass through a 200 mesh screen.
5. A method of making a stiff foam having a slow drain time comprising the steps of:
making a foamable concentrate by adding to water a pre-gelatinized cationic modified starch having a degree of substitution of at least approximately 0.02 and a nitrogen content of at least approximately 0.15%, and a stabilized hydrolyzed protein;
diluting said foamable concentrate with water to produce a foamable liquid; and
introducing a gas into the foamable liquid to produce a foam.
6. The method according to claim 5 , in which, when the pre-gelatinized cationic modified starch is added to the water, the water is at a temperature in the range from approximately 10° C. to 60° C.
7. The method according to claim 5 , in which, when the pre-gelatinized cationic modified starch is added to the water, the water is at a temperature in the range from approximately 15° C. to 30° C.
8. The method according to claim 5 , in which the pre-gelatinized cationic modified starch, when added to the water, has a particle size distribution such that not more than about 25% by weight of the starch would pass through a 200 mesh screen.
9. The method according to claim 5 , in which, when said foamable concentrate is diluted with water, the water with which said foamable concentrate is diluted is at ambient temperature.
10. The method according to claim 5 , in which the pre-gelatinized cationic-modified starch has a degree of substitution in the range from approximately 0.02 to 0.2.
11. The method according to claim 5 , in which the pre-gelatinized cationic-modified starch has a nitrogen content in the range from approximately 0.15% to 2.0%.
12. The method according to claim 5 , in which the pre-gelatinized cationic-modified starch has a degree of substitution in the range from approximately 0.02 to 0.2 and a nitrogen content in the range from approximately 0.15% to 2.0%.
13. The method according to claim 5 , in which the pre-gelatinized cationic-modified starch has a degree of substitution of approximately 0.04.
14. The method according to claim 5 , in which the pre-gelatinized cationic-modified starch has a nitrogen content of approximately 0.35%.
15. The method according to claim 5 , in which the pre-gelatinized cationic-modified starch has a degree of substitution of approximately 0.04 and a nitrogen content of approximately 0.35%.
16. The method according to claim 5 , in which the foamable concentrate, when diluted with water in the dilution step, also comprises ferrous sulfate.
17. The method according to claim 5 , in which the foamable concentrate, when diluted with water in the dilution step, also comprises a dispersant.
18. The method according to claim 5 , in which the foamable concentrate, when diluted with water in the dilution step, also comprises a dispersant composed of a combination of ammonium lignosulfonate and sodium lignosulfonate.
19. The method according to claim 5 , in which the foamable concentrate, when diluted with water in the dilution step, also comprises ammonium hydroxide.
20. The method according to claim 5 , in which the foamable concentrate, when diluted with water in the dilution step, also comprises ferrous sulfate, a biocide, ammonium hydroxide, ammonium lignosulfonate and sodium lignosulfonate.