Biocementation systems and methods
The present disclosure provides a method of biocementation comprising contacting a granular, cohesionless soil with a solution, wherein the solution comprises urea, urease, a source of calcium ions, and a source of non-urease proteins, wherein the urea, urease, source of calcium ions, and source of non-urease proteins are provided in effective amounts suitable to cause crystallization of calcium carbonate.
1. A method of biocementation comprising:
treating, via only one treatment cycle, a granular, cohesionless soil with a solution comprising:
urea;
urease;
a source of calcium ions; and
a source of non-urease proteins, wherein the urea, urease, source of calcium ions, and source of non-urease proteins are provided in effective amounts suitable to cause crystallization of calcium carbonate, and wherein the source of non-urease proteins comprises an enzyme stabilizer; and
responsive to the only one treatment cycle, forming an enzyme induced carbonate precipitation (EICP) treated soil comprising an unconfined compressive strength of greater than 0.5 MPa and a carbonate content of less than 3% by weight.
2. The method of claim 1 , wherein the enzyme stabilizer comprises nonfat milk powder.
3. The method of claim 2 , wherein the solution comprises about 4 grams/liter non-fat milk powder.
4. The method of claim 3 , wherein the source of calcium ions comprises calcium chloride dihydrate.
5. The method of claim 3 , wherein the solution comprises about 0.25 M to about 0.67 M calcium chloride.
6. The method of claim 3 , wherein the solution comprises about 0.37 M to about 1 M urea.
7. The method of claim 3 , wherein the solution comprises about 0.85 g/L to about 3 g/L urease.
8. The method of claim 1 , wherein the enzyme stabilizer comprises casein.