The Application of Depth of Formation Damage Measurements in Predicting Water Injectivity Decline

Abstract

Pressure maintenance by sea water injection is part of many offshore field developments. Experiences gained over the last decade in the North Sea, where there is a wide variance in the systems used, appears not to have clarified design specifications.The paper describes various approaches to analysing water quality criteria with reference to water injection schemes and presents the philosophy of the interrelated approach of laboratory experiments, theoretical models and well injectivity predictions in relation to reservoir characteristics.Results are presented from a laboratory and modelling investigation of permeability impairment as a function of the depth of invasion.A pore network model is described which is generated from laboratory derived pore size distribution data.Predictions of permeability from the model are compared to experimental values and good agreement is demonstrated.The incorporation into the model of particle capture mechanisms enables it to be used to predict the reduction in permeability of a core arising from injection fluids.Another modelling approach is described where the contribution of pore size to permeability is demonstrated.Water quality experimental results are presented showing permeability profiles obtained using a multiport pressure tapped core holder which demonstrate local permeability impairment as a function of particle size and rock properties.The results of one modelling approach is applied in the paper to the prediction of well injectivities and filtration requirements.

Permeability Reduction in Qishn Sandstone Specimens due to Particle Suspension Injection

“…Formation and well impairment due to particle invasion during produced water re-injection has been extensively studied using experiments (e.g., Barkman and Davidson 1972;Abrams 1977;Davidson 1979;Muecke 1979;Todd et al 1984;Eylander 1988;Vetter et al 1987;Sharma and Yortsos 1987;Todd et al 1990;van Oort et al 1993;Roque et al 1995;Pandya et al 1998;van den Broek et al 1999;Veerapen et al 2001;Moghdasi et al 2004;Al-Abduwani et al 2003;Al-Abduwani et al 2005). Roque et al (1995) proposed four different particle retention phases: deposition, bridging, internal accumulation, and external accumulation.…”

A network model for deep bed filtration of solid particles and emulsion drops

“…The network model was first used to simulate formation damage by Todd et al (1984), who used an unbiased random walk to move the particles through the network. Two methods of capture were employed in the simulations: random capture and capture by y3rd-ydh geometric rule.…”

The Impact of Kinetic Hydrate Inhibitors Within Produced Water on Water Injection/Disposal Wells

“…Measure produced water permeability at near wellbore temperature (rates 0, 15ml/h, 30ml/h, 60ml/h, 90 ml/h). 15. Inject 100 PV of formation water pH 6.…”

“…Injection water quality has been studied extensively [5][6][7][8][9][10][11][12][13][14][15][16][17][18] . The impact of solids suspended in seawater 5,6,[13][14][15] and in reinjected produced water 10 have been compared.…”

“…The impact of solids suspended in seawater 5,6,[13][14][15] and in reinjected produced water 10 have been compared. In addition, the effects of fracturing injection wells 2,12 , either as a result of injection above the fracture pressure, or as a result of reservoir cooling, have emerged to be very important.…”