Retrofitting depleted oil wells to extract geothermal energy is considered as one of the promising proposals to extend the overall economic life of oil and gas well. For successful implementation of this initiative, a comprehensive overview covering all aspects of geothermal energy extraction from abandoned oil well should be taken into account including technical, economic considerations as well as regulations and policies of respective local governments. Unfortunately, most reported studies have been focused only on one or two aspects, primarily on technical and economic aspects. Little or no study has focused on the policy sector. Moreover, these findings have been scattered, creating difficulties to extract essential information and dragging further development of the technology. This paper is therefore prepared with the objective to provide a comprehensive overview on the geothermal energy extraction from abandoned oil well, technical challenges in its implementation, economical consideration on the conversion of the well and government policy on energy especially geothermal energy and regulation on the utilization of abandoned oil well. To achieve this objective, extensive literature reviews are conducted with more attention given to recent studies on the field. Challenges on the development of this technology are discussed from technical, economic, and policy perspectives. Based on the identified challenges, required research and development as well as necessary policies for further advancement of this technology are outlined and discussed. By providing this comprehensive information, this review paper may serve as a good foundation and guidelines on the conversion of abandoned oil wells into geothermal energy wells. 相似文献
The effect of chemistry on low energy recoil events was investigated at 10 K for each type of atom in pyrochlores, using molecular dynamics simulation. Contour plots of the threshold displacement energy (Ed) in Gd2Zr2O7 have been produced along more than 80 directions for each individual species. The Ed surface for each type of atom in Gd2Zr2O7 is highly anisotropic; Ed of Zr exhibits the largest degree of anisotropy, while that of O8b exhibits the smallest. The recommended values of Ed in Gd2Zr2O7 based on the observed minima are 56, 94 and 25 eV, respectively, for Gd, Zr, and O. The influence of cation radius on Ed in pyrochlores A2B2O7 (with A‐site ranging from Lu3+ to La3+ and B‐site ranging from Ti4+ to Ce4+) was also investigated along three directions [100], [110], and [111]. The Ed in pyrochlores strongly depended on the atom type, atom mass, knock‐on direction, and lattice position. The defects produced after low energy displacement events included cation antisite defects, cation Frenkel pairs, anion Frenkel pairs, various vacancies, and interstitials. Ce doping in pyrochlores may affect the radiation response, because it resulted in drastic changes in cation and anion displacement energies and formation of an unusual type of anti‐site defect. This work demonstrates links between Ed and amorphization resistance. 相似文献
Degradation parameter or deviation parameter from normal to failure condition of machine part or system is needed as an object of prediction in prognostics method. This study proposes the combination between relevance vector machine (RVM) and logistic regression (LR) in order to assess the failure degradation and prediction from incipient failure until final failure occurred. LR is used to estimate failure degradation of bearing based on run-to-failure datasets and the results are then regarded as target vectors of failure probability. RVM is selected as intelligent system then trained by using run-to-failure bearing data and target vectors of failure probability estimated by LR. After the training process, RVM is employed to predict failure probability of individual units of machine component. The performance of the proposed method is validated by applying the system to predict failure time of individual bearing based on simulation and experimental data. The result shows the plausibility and effectiveness of the proposed method, which can be considered as the machine degradation assessment model. 相似文献
As a biocompatible porous material, bio-MOF is a very promising material as a carrier for hydrophobic drugs, including curcumin. However, the stability of bio-MOF against water and humidity still needs to be improved; therefore, surface modifications are required. This study aims to modify the MIL-100(Fe)-based bio-MOF through core–shell architecture by employing mesoporous silica nanoparticles (MSNs or SiO2) for improving the stability and performance of MIL-100(Fe) to provide a slow-release feature of curcumin. The composites were synthesized via sonochemistry-assisted or mechanochemistry-assisted green protocol to form core–shell structure of MIL-100(Fe)@SiO2 (Composite-1) or SiO2@MIL-100(Fe) (Composite-2). Structural, textural, and morphological analyses, including XRD, FTIR, SEM, TEM, and N2 adsorption–desorption, are discussed in this study to evaluate the composite formation. BET surface area of the MIL-100(Fe) decreased from 1197.45 m2/g to 565.63 and 823.70 m2/g after forming composite-1 and composite-2 with SiO2. The loading capacity, however, just increased slightly up to 97.89% after the modification. The presence of SiO2 as shell (composite-1) protects the MIL-100(Fe) from degradation under the acidic condition at pH 5.8 and can maintain the slow-release of curcumin. In contrast, the presence of SiO2 as core (composite-2) induces the sustained release due to faster degradation of MIL-100(Fe) in acidic condition. Both composites serve as a model for either sustained release or delayed release drug delivery systems.
In this research, the performance of metal–organic frameworks (MOFs) of MIL-101(Fe) and MOF-808 as aspirin detoxification agents was evaluated. MIL-101(Fe) was successfully prepared for the first time using the electrochemical method for 30 min under room temperature and pressure. MIL-101(Fe) detoxification capacity was compared to that of MOF-808, which was synthesized by a common solvothermal method at 135 °C for 24 h. The obtained materials were fully confirmed by X-ray diffraction (XRD) with the appearance of MIL-101(Fe) characteristic peaks (at 2θ 8.5°; 9°;16.7°) and MOF-808 (at 2θ 8.3°; 8.7°; 10°; 10.9°), and also confirmed by Fourier transform infrared (FTIR) spectroscopy that shows the coordination between metal and ligand. Based on scanning electron and transmission electron microscopy (SEM and TEM), MIL-101(Fe) has a micro-spindle shape with average particles size of 649.12?±?73.32 nm, while MOF-808 showed irregular shape with average particle sizes of 169.73?±?31.87 nm. Nitrogen sorption isotherm confirmed that both materials could be classified as micro to-meso porous materials by the pore radius of 1.89 nm for each materials with BET surface areas of 131 for MIL-101(Fe), and 847 m2/g for MOF-808, respectively. Based on an in vitro test, in a gastric simulation, MIL-101(Fe) decreased 11.78% of aspirin, while MOF-808 decreased 7.99%. In the intestinal simulation, MIL-101(Fe) and MOF-808 decreased aspirin by 24.06% and 26.74%, respectively. XRD analysis of the MOFs after the detoxification test showed that MIL-101(Fe) has lower stability than MOF-808. FTIR spectra confirmed that aspirin was successfully adsorbed into the MOFs. Transmission electron microscopy showed that aspirin interacted with MIL-101(Fe) on the outer surface and with MOF-808 on the inside of the pores.
