Patent · US Expired

Particulate ceramic useful as a proppant

US4680230A · kind A · utility

92Cited by
17References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 18, 1984
Grant dateJul 14, 1987
Priority date
Expiry dateJan 18, 2004

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/2998
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A two-phase ceramic particulate useful as a proppant in hydraulic fracturing operations is provided which comprises a vitreous matrix phase containing a crystalline alumina phase. The new ceramic particles are characterized by: PA0 (i) a concentration gradient of alumina which increases from very low in the center to relatively high near the surface of the particles; PA0 (ii) a fired density less than about 2.9 g/cc; and PA0 (iii) closed cell microporosity. Certain embodiments of the inventive ceramic particulate are also characterized by a Krumbein roundness of at least 0.8 and are chemically stable. The ceramic is made by a process comprising the steps of: PA0 a. mixing and pelletizing, with the aid of water, the dry raw materials including a mineral particulate such as nepheline syenite and a binder such as bentonite; PA0 b. drying the wet pelletizer product; PA0 c. mixing the dried pellets with a parting agent; and PA0 d. firing the mixture of pellets and parting agent at sufficient temperature and for sufficient time to cause vitrification to occur.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.