Over a 14 month period, a mature field in Mexico's southern region experienced a gradual increase in water cut from 0 to 85%, with an associated decrease in oil production from 166 BOPD (barrels of oil per day) to 57 BOPD.
Methods to mitigate this problem include blocking gels, cement, microcement, silicates, and other materials. Because these materials all act as sealing agents, the water zone must be isolated from the hydrocarbon zone, usually requiring the use of mechanical or chemical systems and, in most applications, the use of equipment for major workovers. However, in this case the operator opted to implement a new technology involving the use of a hydrophobically modified polymer (HMP), Halliburton's WaterWeb® service. The deployment of this technology was based on projected cost reductions, execution simplicity and quick response.
Production data following the treatment showed a gradual water reduction from 85% to 58%, after two months. This finding represents a decrease of 30%. Six months after the treatment was applied, the water cut had dropped by 68%. Hydrocarbon production increased from 57 to 104 BOPD (an 82% increase) due to the lowering of the hydrostatic column in the well. This increase demonstrates that the HMP neither damaged nor reduced permeability to hydrocarbon in the interval. In terms of economics and profitability, six months after the treatment was applied, $250,000 had been added to the hydrocarbon production at present value. Savings are $187,000 in terms of intervention costs and $33,000 for surface-water handling costs at present value.
For more information about WaterWeb service, consult SPE paper 102711 or contact your local Halliburton representative.