Produced water re-injection in a non-fresh water aquifer with geochemical reaction, hydrodynamic molecular dispersion and adsorption kinetics controlling: model development and numerical simulation

Abstract

An improved produced water reinjection (PWRI) model that incorporates filtration, geochemical reaction, molecular transport, and mass adsorption kinetics was developed to predict cake deposition and injectivity performance in hydrocarbon aquifers in Nigeria oil fields. Thus, the improved PWRI model considered contributions of geochemical reaction, adsorption kinetics, and hydrodynamic molecular dispersion mechanism to alter the injectivity and deposition of suspended solids on aquifer wall resulting in cake formation in pores during PWRI and transport of active constituents in hydrocarbon reservoirs. The injectivity decline and cake deposition for specific case studies of hydrocarbon aquifers in Nigeria oil fields were characterized with respect to its well geometry, lithology, and calibrations data and simulated in COMSOL multiphysics software environment. The PWRI model was validated by comparisons to assessments of previous field studies based on data and results supplied by operator and regulator. The results of simulation showed that PWRI performance was altered because of temporal variations and declinations of permeability, injectivity, and cake precipitation, which were observed to be dependent on active adsorption and geochemical reaction kinetics coupled with filtration scheme and molecular dispersion. From the observed results and findings, transition time t r to cake nucleation and growth were dependent on aquifer constituents, well capacity, filtration coefficients, particle-to-grain size ratio, water quality, and more importantly, particle-to-grain adsorption kinetics. Thus, the results showed that injectivity decline and permeability damage were direct contributions of geochemical reaction, hydrodynamic molecular diffusion, and adsorption kinetics to the internal filtration mechanism, which are largely dependent on the initial conditions of concentration of active constituents of produced water and aquifer capacity.

Prediction of Pressure Increase during Waste Water Injection to Prevent Seismic Events

“…Numerous studies investigated the slippage potential of faults and fractures in different ways, including analytical calculation, numerical simulation, and semi-analytical methods [22][23][24]. Most studies rely on the understanding of both the geological and mechanical properties of the faults and fractures in the formations.…”

Modeling fracturing pressure parameters in predicting injector performance and permeability damage in subsea well completion multi-reservoir system

“…Improved models and field data to describe the role of geochemical reaction, adsorption-scale kinetics were recently published to impact cake formation, permeability damage and injection performance (Obe et al 2017). Nonetheless, the wellestablished field data for fractured modeling in most cases show more than these parameters including filtration coefficient k characterizing the intensity of the particle capture by the porous rock, while formation damage coefficient b shows permeability decrease due to particle capture (Pang and Sharman 1994;AlAbduwani et al 2001;Guo 2000;Meyer et al 2003a, b).…”