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Oil & Gas Technologies

 

Enhanced Oil Recovery Conformance Control Gels

A customer requested we develop an improved silicate gel to use in conformance control.  More than 60 years ago, sodium silicate was used in conformance gels with an initiator to plug of high permeability areas of the oil & gas producing formation. The problem with these gels was the requirement to pump the two different fluids in alternating stages since the two reacted rapidly to form brittle, pasty gels. We were also well aware of the hazardous chromium VI gels with partially hydrolyzed polyacrylamide developed in the 70’s & 80’s that are still used today.  A discovery was made using different initiators, a linear polymer and other stabilizing components with the sodium silicate that resulted in a time delayed gel possessing ringing elasticity and three to ten times more gel strength that the chromium-polymer gels. These gels are called SPI gels today which stands for Silica Polymer Initiator. They were versatile enough to be delayed for significant periods of time to allow in-depth penetration treatments in water floods or form hard elastic gels for casing leak repairs. We found they could even be used for water divergence around house foundations. Recent lab and field testing efforts suggested they are excellent conformance gel products for CO2 flooding.

The Clean Tech - Rendezvous Resources laboratory team performed core and sand pack testing at reservoir pressures and temperatures up to 2,500 psi and 180 oF using CO2 as the gelling agent. The results showed significant ΔP in the sand pack resulting from the gels at commercial flow rates of 1 foot per day and higher. Three successful field tests have been conducted showing similar results providing increased oil production and decreased water and CO2 production.  More testing is anticipated.

This work was supported by the independent customer, Department of Energy (DOE), OCAST and the Stripper Well Consortium (SWC) in a DOE Prime Cooperative Agreement with Penn State University.

 

Polymer Flooding

A large oil and gas company where Mr. Burns was previously employed had a chemical operation which sold drilling and cementing additives into the oil and gas industry.  This business was expanding into Production Chemicals sales.  One of the product leaders was a High Temperature High Salinity stable polymer for use in polymer flooding.  This was a large project R & D effort for the company.  We were effective in developing one of the best products available for the application.  Unfortunately, by the time the project was ready for field testing and commercialization, oil prices dropped from $38 to $10/bbl, the industry became depressed for several years and polymer flooding never became the enhanced oil recovery technique earlier desired.  None-the-less, the water soluble polymer knowledge is present at Clean Tech Innovations.

 

High Temperature Acid Gelling Agent for Hydraulic Acid Fracture Stimulation

A large oil and gas company where Mr. Burns was previously employed had a chemical operation which sold drilling and cementing additives into the oil and gas industry. They felt the market and the parent oil & gas company had a need for a high temperature acid gelling agent for hydraulic acid fracturing in its worldwide operations.  Gelled acids retard the reactivity of carbonate formations such that the acid is not spent in a short fracture length, but instead, allows significantly longer live acid penetration deep into the reservoir. This was the perfect challenging opportunity for an individual who had entrepreneurial flair, yet technical knowledge of the subject matter to be able to take a project from invention to commercialization and marketing/sales.  Within two years the product was developed in R & D and ready for field testing in the US and later at several world-wide well locations. The field test conclusions indicated the gelling agent was very stable in 28% hydrochloric acid up to 300 oF for a long enough period of time to pump 60,000 barrels of gelled acid fluid.  After a reasonable shut-in time, the gelled acid fluid broke down to a low viscosity for flow back without damaging the fracture or wellbore area.  Proof of this concept was found in the decline curves in the years following the treatments.  We noted that when the wells stabilized after stimulation, they stayed at that stabilized level for four years or more beyond where the wells had previously started the natural decline rate.  After this decline has started, it is normally time to start considering another stimulation treatment.  Four years of production in this manner could be considered additional profitability for the well before more stimulation investment is required.  Mr. Burns continued with this project through field testing to marketing and sales.  The product is still reported to be a significant product contributor in this decade.

 

Drilling and Completion Activities

Although Clean Tech Innovations does not have a specific product or technology falling into the domain of drilling and completion activities, it has been around these types of projects.  Clean Tech has the knowledge of the product additives and the properties required for these additives.