| abstract |
A process for recovering hydrocarbonaceous fluids from a formation having a substantially low pH where a rehealable gel prepared ex-situ is used to close off a zone of greater permeability. Said gel is obtained by mixing into an aqueous medium sufficient biopolymer amounts of a Xanthan or Alcaligene polysaccharide. This mixture is maintained at a pH of about 5.5 while an aminoplast resin in excess of 4,000 ppm is added thereto which causes said gel to form in about 0.5 to 6 hours. The resultant gel is suitable for use in a carbon-dioxide flood process. Said gels are very stable at a pH of less than about 5.5. |