Investigation of the Effect of Water Quality on Formation Damage using Porous Discs

Investigation of the Effect of Water Quality on Formation Damage using Porous Discs

de Jonge, Maurits (TU Delft Civil Engineering and Geosciences)

Zitha, Pacelli (mentor)
Voskov, Denis (mentor)
Gebert, Julia (mentor)
Welling, Marco (mentor)

Delft University of Technology

Applied Earth Sciences

2020-06-18

Water injection is widely used in the petroleum industry for the increase of hydrocarbon recovery or disposal of wastewater. Water production and injection are the primary mechanisms in Geothermal Energy. Both include injecting water into a porous formation under matrix injection conditions. While maintaining water injection is vital in these branches in the industry, so is the occurrence of formation damage (FD) due to suspended contaminants or brine incompatibility. Suspended particles in injection water are retained or deposited due to the creation of an External Filter Cake (EFC) or Internal Filter Cake (IFC) impairing the permeability. Consequently, FD results in Water Injectivity Decline (WID). In most cases, the negative impact on injectivity translates into operational and economic targets not being met. WID, as a result of FD, is highly connected to the Water Quality (WQ) of the injection water. A new approach to water quality (WQ) testing is proposed which suffices as a bridging application of membrane filtration and core flooding. To establish a foundation for this method, tests are conducted by performing particle-laden suspension injection experiments with porous outcrop sandstone 8 mm thin discs utilizing the ‘Con-vergence Hydra’. An experimental study is conducted investigating the effect of water quality (WQ) on formation damage, using dilute (20-100 mg/l) Baracarb2 (CaCO3) particle suspension as a model contaminant. Baracarb2 is tested for particle size distribution, mineral content and stability within synthetic brine (resembling Seawater). Subsequently, suspension flow experiments are conducted on porous thin discs (Bentheimer & Berea sandstone) as well as membrane filters (MF0.45μm). As performing suspension injection test with porous thin disc test utilising the Hydra has not been done before, reproducibility of the experiments is tested. The reproducibility of performing experiments utilising the Hydra is high, with very little difference between the experimental outcomes.Varying WQ within each different porous media type illustrates remarkably similar trends. Moreover, it is demonstrated that by performing a similarity curve collapse, a master curve is obtained for each porous medium type which scales with suspension concentration for Baracarb2. The damage mechanisms explaining this master curve all demonstrate a linear permeability impairment in the early part of the experiments. Subsequently, a linear impedance trend is observed where it is assumed that cake filtration is dominant. The latter is demonstrated by calculating the Modified fouling Index (MFI), which shows a linear dependency with suspension concentration. SEM imaging and Micro-CT scan images substantiate the damage mechanisms hypothesized from the pressure and rate data.The Con-vergence Hydra utilising porous thin discs has great potential for on-site testing which allows fast and reliable results on permeability impairment, i.e. formation damage. Subsequently, monitoring of the water quality can be done by performing MFI analysis during cake filtration. 

Water quality
Formation damage
Con-vergence Hydra
Baracarb2
Calcium carbonate
Porous sandstone disc
MFI

http://resolver.tudelft.nl/uuid:a6b4ed98-a46c-4878-9cca-e97dbf753167

2020-06-18

Student theses

master thesis

© 2020 Maurits de Jonge