Stabilizing coal-water mixtures with portland cement

• US 4,602,918 A
• Filed: 10/17/1984
• Issued: 07/29/1986
• Est. Priority Date: 10/17/1984
• Status: Expired due to Fees

• Current Assignee: United States Department of Energy
• Original Assignee: United States Department of Energy
• Inventors: Steinberg, Meyer, Krishna, Coimbatore R.
• Primary Examiner(s): Dixon, Jr., William R.
• Assistant Examiner(s): Medley, Margaret B.
• Application Number:
  US06/661,841
• Time in Patent Office: 650 Days
• Field of Search: 44/51, 44/76, 44/15 R, 44/1 R
• US Class Current: 44/280
• CPC Class Codes: C10L 1/326 Coal-water suspensions

Abstract

Coal-water mixes stabilized by the addition of portland cement which may additionally contain retarding carbohydrates, or borax are described.

Claims

1. A coal-water mix for use as a fossil fuel containing up to 70% by weight coal particles, based on the total weight of the mix, stabilized by the presence in the mix of up to 15% by weight, based on the weight of the coal, of portland cement, said portland cement stabilizing the mix by greatly extending the time that the coal particles remain in suspension, thus eliminating problems of transporting and storing the mix which result when said coal particles come out of suspension.

2. A coal-water mix as in claim 1 wherein the portland cement is type III portland cement.

3. A coal-water mix as in claim 1 additionally containing a carbohydrate to retard the hardening of the mix.

4. A coal-water mix as in claim 3 wherein the retarding carbohydrate concentration is up to 2% based on the weight of the cement.

5. A coal-water mix as in claim 1 additionally containing from 0.1% to 2% by weight borax, based on the total weight of the mix, said borax decreasing the amount of portland cement required in the mix.