Investigation of the role of electrokinetic effects in corrosion deposit formation

A review on clogging of recirculating steam generators in Pressurized-Water Reactors

“…Investigation of the electrokinetic effect, which may be another strengthening mechanism of iron precipitation, should be conducted to evaluate its contribution to TSP clogging formation. The experimental deposit and protocol developed by Scenini [69] seem adapted to this purpose. Advanced modelling works should simultaneously be carried out with representative test loop experiences and electrokinetic studies, to well define local parameters.…”

“…Scenini et al [69] recently investigated the role of electrokinetic effects in corrosion deposit formation in primary circuit. A miniature flow cell was designed in order to accelerate fluid flow and produce negatively charged regions onto electrodes evidenced by recording polarization curves.…”

Finite Element Modelling to Investigate the Mechanisms of CRUD Deposition in PWR

“…Work on CRUD deposition in micro-orifices with very high flow velocities has been performed by Scenini et al [11]. The electrochemical potential distribution through the annulus of a test has been measured [12] and the anodic and cathodic behaviour of the current component at the front face of an orifice where the CRUD is known to deposit has been investigated [13].…”

Development of a microfluidic setup to study the corrosion product deposition in accelerated flow regions

“…The use of microfluidic systems for such investigations also allows the electrical behaviour of separate regions of the system to be measured, which has been shown by the current authors to enable investigations of the electrokinetic behaviour of such systems. 16 The aims of the work presented in this paper are: (i) to develop a small-scale microfluidic system that enables investigation of CRUD deposition under accelerated flow conditions in simulated PWR conditions, (ii) to validate the hydrodynamics of the setup and correlate the pressure drop across a restriction with the microorifice diameter to allow the online measurement of CRUD buildup and (iii) to provide an example of how real time pressure and flow measurements can be used to investigate the effect of water chemistry on CRUD deposition. The addition of pressure drop measurements to complement the electrical monitoring of the microfluidic system already demonstrated will further enhance the usefulness of this approach in understanding the coupling between mechanical and electrokinetic factors in CRUD deposition.…”

“…While the Faradaic current can increase the release of metal ions into the water, the wall current might also further oxidise the Fe 2+ ions and, ultimately, induce the formation of magnetite. 16 Streaming currents become important in low conductivity solutions as the diffuse layer is thick. The magnitude of streaming currents that can be generated depends on a number of factors including solution water chemistry, 8 flow velocity, 17 electrochemical potential 18 and material.…”