EOR Solutions
Conformance Improvement and Water Shut-Off

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There are many types of conformance problems and many different conformance-improvement (water-shutoff and sweep-improvement) technologies. The challenge is to correctly identify the offending conformance problem and then to select, design, and execute an appropriate conformance-improvement technology. Conformance-improvement treatments are reservoir-, well-, and problem-specific.

APPLICATION
The gel can be injected into production or injection wells and can solve the following problems:

	Producing Wells: Bottom water coning, early water breakthrough, fracturing out of zone, conduit from injector to producer, natural fractures connected to bottom water drive
	Injection Wells: Conduit from injector to producer, injection out of zone, thief intervals of natural fractures or high permeability streaks

DESCRIPTION
The gel is made up of a polymer and a crosslinker. The polymer and crosslinker are added at the surface, then injected down into the formation. The reaction rate is sufficiently delayed to allow placement some distance from the wellbore.

ADVANTAGES
	Robust, versatile gel chemistry that does not require exact chemical concentrations
	Can be used in almost any type of mix water
	80% success at reducing water production at least 60% without reducing oil
	May not require zone isolation in fractured reservoirs
	Can place large volumes to block water flow paths further out from the wellbore than other methods, which reduces new flow paths bypassing the gel
	Works up to 210°F
	Payout is often within 6 to 9 months, based on incremental oil production alone

CRITICAL DESIGN FACTORS
	Producers with surface fluid levels are excellent candidates
	Perfs must be clean so the gellant can be readily injected
	Minimum efficient injection rate and maximum injection pressure constrain treatment volumes
	Should be able to place at least 1,000 BBLS of gel without reaching pressure limit