Removal of paracetamol from aqueous solution by containment composites

Storage of wastes leads to severe problems of water pollution and neighboring matrices due to the infiltration of landfill leachate. Uncontrolled landfill and waste storage can lead to groundwater pollution, which can lead to serious health problems for the living. Engineered barriers can be a solution to these pollution problems. The purpose of this study was to develop novel composite materials – clay-based, activated carbon, cement, and PVA polymer. These composites were intended for the containment of waste in landfill. The clay (70–80%) and activated carbon (5–15%) contents were varied to obtain three different geomaterials – GM1, GM2, and GM3. In the preparation of GM3, the content of activated carbon used was higher than for GM1 and GM2, paracetamol removal capacity tested by adsorption, experiments were influenced by parameters such as the adsorbent mass, the initial solute concentration, contact time, temperature, and pH effect. The parameter of initial paracetamol concentrations was studied using a range of 50, 100, and 150 mg L−1. For a GM3 mass of 80 mg, the adsorbed amount is 14.67 mg g−1, and the contact time is 180 minutes. This study revealed that composites are efficient for the treatment of landfill leachates.

Noncontact Displacement Measurement of Nuclear Waste Canisters in a Geological Disposal by Using an Electromagnetic-Wave Approach

The aim of this work is to show a preliminary investigation of possible noncontact techniques for displacement measurement of radioactive waste in a geological disposal. Since a nuclear waste repository can be considered as a harsh environment, the possibility to study alternative methods for measurement, for example, not using cables or buses for detecting relevant data, should be considered as a priority. A straightforward approach could be the substitution of cables with wireless sensors. But if cables cannot be used and the use of wireless techniques is required, new sensors must assure a reliable transmission without affecting the engineered barriers performance and the reliable use of energy supply for the measuring equipment over long periods. This work shows the results of a study of feasibility on using an electromagnetic (EM) approach for the contactless displacement measurement of a canister immersed and suspended in bentonite, a material with a high degree of water retention.

Concept of Large-scale Thermomechanical URL Experiments in the Nizhnekanskiy Rock Massif

Numerical simulation of thermomechanical processes in a deep underground radioactive waste repository requires information on the host rock and the engineered barriers properties at a scale of dozens of centimeters, meters and more. However, the extrapolation of the values obtained on small-scale samples in surface laboratories yields excessive uncertainties. The materials behavior is also influenced by conditions that cannot be reliably reproduced in a surface laboratory, such as water content or initial stress-strain state. Following experiments are planned to study the host rock and the engineered barriers behavior during heating under conditions similar to those expected in the repository, as well as to assess their large-scale thermomechanical properties. In the experiment focused on the excavation damaged zone thermal mechanics, the behavior of reinforced drift walls and vaults under heating will be studied. The experimental facility will involve two drifts with the same orientation as the planned repository ones. As a result, the spatial distribution of excavation damaged zone thermomechanical parameters and their evolution due to heating will be identified. The second experiment focuses on the host rock mass behavior under spatially nonuniform unsteady heating. The facility will feature two vertical boreholes with heaters. The experiment will be divided into several stages: study of the host rock initial state, estimation of the rock main thermomechanical properties, study of the temporal evolution of the stress field due to 3D temperature gradients and of the processes in the host rock occurring during its cooling and re-saturation with water. Following the completion of the separate-effect test program, an integrated experiment should be carried out to study the coupled processes with respect to their mutual influence. The obtained results will be used to refine the values of input parameters for numerical simulations and their uncertainty ranges, as well as to validate the computer codes.

Beacon: bentonite mechanical evolution

The aim of Beacon is to develop the understanding of fundamental processes that lead to material homogenisation, as well as to improve capabilities for numerical modelling. In earlier assessments of bentonite EBS, the mechanical interaction between the installed bentonite components has been neglected and an “ideal” final state has generally been assumed. Key features of the project are (1) re-evaluation of the available knowledge to extract the crucial data to compile the qualitative and quantitative data and to enhance the conceptual understanding. (2) Enhanced, robust and practical numerical tools based on a good scientific understanding, which have the expected predictive capabilities regarding the evolution of engineered barriers and seals. (3) A developed database with experimental data needed by the quantitative models. (4) Verified calculation tools based on experimental results in different scales. The Beacon project is required for the pan-European objectives at building confidence amongst regulators and stakeholders regarding the performance of the engineered barriers in a geological repository.