Capillary trapping for geologic carbon dioxide storage - From pore scale physics to field scale implications

AbstractA significant amount of theoretical, numerical and observational work has been published focused on various aspects of capillary trapping in CO2 storage since the IPCC Special Report on Carbon Dioxide Capture and Storage (2005). This research has placed capillary trapping in a central role in nearly every aspect of the geologic storage of CO2. Capillary, or residual, trapping – where CO2 is rendered immobile in the pore space as disconnected ganglia, surrounded by brine in a storage aquifer – is controlled by fluid and interfacial physics at the size scale of rock pores. These processes have been observed at the pore scale in situ using X-ray microtomography at reservoir conditions. A large database of conventional centimetre core scale observations for flow modelling are now available for a range of rock types and reservoir conditions. These along with the pore scale observations confirm that trapped saturations will be at least 10% and more typically 30% of the pore volume of the rock, stable against subsequent displacement by brine and characteristic of water-wet systems. Capillary trapping is pervasive over the extent of a migrating CO2 plume and both theoretical and numerical investigations have demonstrated the first order impacts of capillary trapping on plume migration, immobilisation and CO2 storage security. Engineering strategies to maximise capillary trapping have been proposed that make use of injection schemes that maximise sweep or enhance imbibition. National assessments of CO2 storage capacity now incorporate modelling of residual trapping where it can account for up to 95% of the storage resource. Field scale observations of capillary trapping have confirmed the formation and stability of residually trapped CO2 at masses up to 10,000tons and over time scales of years. Significant outstanding uncertainties include the impact of heterogeneity on capillary immobilisation and capillary trapping in mixed-wet systems. Overall capillary trapping is well constrained by laboratory and field scale observations, effectively modelled in theoretical and numerical models and significantly enhances storage integrity, both increasing storage capacity and limiting the rate and extent of plume migration

Hip1r is expressed in gastric parietal cells and is required for tubulovesicle formation and cell survival in mice

Huntingtin interacting protein 1 related (Hip1r) is an F-actin– and clathrin-binding protein involved in vesicular trafficking. In this study, we demonstrate that Hip1r is abundantly expressed in the gastric parietal cell, predominantly localizing with F-actin to canalicular membranes. Hip1r may provide a critical function in vivo, as demonstrated by extensive changes to parietal cells and the gastric epithelium in Hip1r-deficient mice. Electron microscopy revealed abnormal apical canalicular membranes and loss of tubulovesicles in mutant parietal cells, suggesting that Hip1r is necessary for the normal trafficking of these secretory membranes. Accordingly, acid secretory dynamics were altered in mutant parietal cells, with enhanced activation and acid trapping, as measured in isolated gastric glands. At the whole-organ level, gastric acidity was reduced in Hip1r-deficient mice, and the gastric mucosa was grossly transformed, with fewer parietal cells due to enhanced apoptotic cell death and glandular hypertrophy associated with cellular transformation. Hip1r-deficient mice had increased expression of the gastric growth factor gastrin, and mice mutant for both gastrin and Hip1r exhibited normalization of both proliferation and gland height. Taken together, these studies demonstrate that Hip1r plays a significant role in gastric physiology, mucosal architecture, and secretory membrane dynamics in parietal cells

Influence of injection well configuration and rock wettability on CO2 plume behaviour and CO2 trapping capacity in heterogeneous reservoirs

© 2017 Elsevier B.V. CO2 geo-storage efficiency is highly affected by many factors including formation geology, storage site conditions and properties (e.g. aquifer temperature, aquifer depth, vertical to horizontal permeability ratio, cap rock properties, and reservoir heterogeneity) and the CO 2 injection process (e.g. continues injection, WAG, etc.). However, the impact of well configuration has not yet been addressed in detail. Thus, we compared the efficiency of three different vertical injection well scenarios (i.e. one well, two wells, and 4 wells) with a horizontal injection well in a deep aquifers via computer simulation; and furthermore investigated how rock wettability affects CO 2 plume migration and trapping. The results indicate that the injection well configuration has a major influence on CO 2 plume migration and on the amount of mobile, residual and dissolved CO 2 . A horizontal well reduces CO 2 plume migration, CO 2 mobility and CO 2 solubility trapping, while it improves CO 2 residual trapping. Hence, our results from a previous study, that water-wet rocks are preferable CO 2 storage formations, as they increase storage capacity and containment security, is valid for any injection well configuration. We thus conclude that from a technical perspective horizontal injection wells and from a geological perspective the more water-wet rock are preferable as they increase storage capacity and containment security