Abstract
In this paper we ask the question whether or not electrochemically enhanced deposition of minerals can be utilized to
repair leakage paths existing in cement plugs in wells. Electrical polarization of two electrodes may result in oxygen
reduction and water electrolysis, where both processes change the local pH close to the two electrodes. The solution
close to the anode is becoming acidic while close to the cathode it is becoming alkaline. Since solubility of many
scaling minerals is pH dependent, precipitation of minerals on conductive surfaces can be induced by electrical
polarization. We test whether cathodic polarization of conductive surfaces can be used to facilitate deposition of
minerals from brines resembling reservoir fluids. As a model the reservoir formation water from the Gyda field was
chosen. The electrochemically enhanced deposition at 23 and 120 °C from a synthetic Gyda brine was tested by
polarizing at 5 V. The results show that cathodic polarization significantly enhanced precipitation of minerals from
the synthetic Gyda brine.
repair leakage paths existing in cement plugs in wells. Electrical polarization of two electrodes may result in oxygen
reduction and water electrolysis, where both processes change the local pH close to the two electrodes. The solution
close to the anode is becoming acidic while close to the cathode it is becoming alkaline. Since solubility of many
scaling minerals is pH dependent, precipitation of minerals on conductive surfaces can be induced by electrical
polarization. We test whether cathodic polarization of conductive surfaces can be used to facilitate deposition of
minerals from brines resembling reservoir fluids. As a model the reservoir formation water from the Gyda field was
chosen. The electrochemically enhanced deposition at 23 and 120 °C from a synthetic Gyda brine was tested by
polarizing at 5 V. The results show that cathodic polarization significantly enhanced precipitation of minerals from
the synthetic Gyda brine.