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Abstract: This work was carried out under the specific collaboration agreement between the Bhabha Atomic Research Centre (BARC) from India and the Commissariat à l''Energie Atomique (CEA) from France. This paper summarises first results of review and research on the possible extraction of uranium from the concentrated brine rejected by integrated nuclear desalination systems, which both partners are currently developing in the two organisations. Three innovative and efficient methods of uranium extraction have been proposed: 1) Resin grafted with calixarene: this method has the advantage of very high selectivity. Its performances, especially for large-scale extraction, still need further R&D and optimisation; 2) Magnetic separations: yet another method with high selectivity, easy separation and affording high degree of material recovery. The method, however, is in developmental stage; 3) Canal system with Braid adsorbents: high selectivity. Appears to be feasible in conjunction with existing technology. It would nonetheless require large amounts of adsorbents and adequate infrastructure. [Copyright &y& Elsevier]

Abstract: Seawater desalination is now widely accepted as an attractive alternative source of freshwater for domestic and industrial uses. Despite the considerable progress made in the relevant technologies desalination, however, remains an energy intensive process in which the energy cost is the paramount factor. This study is a first of a kind in that we have integrated the environmental costs into the power and desalination costs. The study has focused on the seawater desalination cost evaluation of the following systems. It is supposed that they will be operating in the co-generation mode (simultaneous production of electrical power and desalted water) in 2015: Fossil fuelled based systems such as the coal and oil fired plants and the gas turbine combined cycle plant, coupled to MED, and RO; Pressurised water reactors such as the PWR-900 and the AP-600, coupled to MED, and RO; High temperature reactors such as the GT-MHR, the PBMR, coupled to MED, with the utilisation of virtually free waste-heat provided by these reactors. The study is made in real site-specific conditions of a site in Southern Europe. Sensitivity studies for different parameters such as the fossil fuel prices, interest and discount rates, power costs etc., have also been undertaken. The results obtained are then used to evaluate the financial interest of selected integrated desalination systems in terms of a detailed cash flow analysis, providing the net present values, pay back periods and the internal rate of returns. Analysis of the results shows that among the fossil fuelled systems the power and desalination costs by circulating fluidized bed coal fired plant would be the lowest with current coal prices. Those by oil fired plants would be highest. In all cases, integrated nuclear energy systems would lead to considerably lower power and water costs than the corresponding coal based systems. When external costs for different energies are internalised in power and water costs, the relative cost differences are considerably increased in favour of the nuclear systems. Financial analysis further confirms these conclusions. [Copyright &y& Elsevier]

Abstract: This paper focuses on a case study of financing a project of an integrated nuclear desalination system at la Skhira site in Tunisia. More specifically, it shows the financial characteristics of this project, known as TUNDESAL, the main financing mechanisms that can be used, and the principal actions required to attract the potential investors and lenders. The paper describes the basic requirements for the deployment of nuclear energy in a developing or an emerging country, with no previous experience of nuclear power; the specific financial considerations corresponding to the particular characteristics of nuclear desalination projects: high capital costs, high level of risks and uncertainties related in particular to long construction lead times and social and environmental concerns; the main risks of these projects; the profitability study of the TUNDESAL project: application of the discounted cash flow analysis; the main financing sources for the project; the financing schemes that can be used for project implementation and comparison between these schemes in terms of benefits generated, after covering project costs and repayment of lenders and investors; the main actions to be done for making the project financially attractive in order to gain the confidence of investors and international financial institutions (optimal allocation of project risks and uncertainties, a suitable and flexible energy and water tariffs policy, etc.). The analysis has shown that in particular conditions of Tunisia, the most attractive financial scheme could be the “project financing + leasing”. [Copyright &y& Elsevier]

Abstract: This paper describes the detailed analyses of power and water costs for several nuclear reactors operating in a cogeneration mode (e.g. the 900 MWe French PWR, the advanced PWR, AP-600, the gas cooled, high temperature reactors, such as the GT-MHR and the PBMR) and coupled to two main desalination processes, e.g. multiple effect distillation (MED) and reverse osmosis (RO). Results for a specific site in a south Mediterranean country, Tunisia, are presented. It is shown in particular how the desalination costs could be further reduced by utilising waste heat from the GT-MHR and the PBMR type of reactors. Comparisons are made with desalination costs from the cheapest of fossil energy based systems, namely the 600 MWe gas turbine, combined cycle plant (CC-600) in various cost scenarios and in conditions specific to the selected site. Calculations are performed using the DEEP-3 software, recently developed by the International Atomic Energy Agency (IAEA). In the light of the results obtained, it is concluded that: a) Compared to the CC-600 system, all nuclear desalination options lead to much lower power production costs, as long as gas prices are ≥150 $/toe, and for discount rates of 5, 8 and 10%. Thus for example, at 8% discount rate and a gas price of 40 $/bbl (291 $/toe) for the CC-600, the kWh cost of the PWR-900 is 56% lower. Under the same conditions, that of the AP-600 is 49% lower; b) If the economic performances of the GTMHR and the PBMR, as announced by their respective developers, are indeed true than the GT-MHR would lead to the lowest kWh costs of all options considered. The kWh cost of the PBMR would be comparable to the large sized PWR-900; c) At 8% discount rate, the MED desalination cost by the PWR-900 and the AP-600 are respectively 46 and 42% lower than the corresponding cost by the CC-600 plant; d) The lowest costs with the MED plants are obtained by the GT-MHR and PBMR, utilising virtually free waste heat. Compared to the cost by the CC-600 + MED system, these reactors give desalination costs which are respectively 62% and 44% lower; e) For all energy sources, the desalination cost with the RO process is lower than with the MED process. [Copyright &y& Elsevier]

Abstract: This paper summarises our investigations on the conceptual studies of the Reverse Osmosis (RO) process with preheating of the feed-water, which is expected to lead to lower specific power consumption and higher water production, thus further reducing the cost of desalination by this advanced RO process. There are, however, no adequate calculation methods to take into account the effect of temperature on the RO system performance parameters such as the recovery ratio, feed pressure, feed flow and the permeate salinity. The work presented here tries to fulfil this need through the elaboration of mathematical correlations expressing the variation of these parameters as functions of the input parameters such as feed temperature, feed salinity, and the desired production capacity. The principle of the method used is to first dimension the RO system with the help of the software ROSA and the membrane SW30 HR380 for a series of calculations (504 cases) giving the variation of the above performance parameters for a large range of the input conditions. Numerical methods were then used to obtain the correlations giving the complete variation of the performance parameters as functions of the input parameters. The correlations were then integrated into the desalination cost evaluation code, DEEP, developed by IAEA and in the course of continued development at CEA. The revised version of the code was then applied to a specific project of nuclear desalination (the TUNDESAL project), currently being carried out in the context of a collaboration agreement between France and Tunisia, under the aegis of the IAEA regional cooperation programme. [Copyright &y& Elsevier]

Abstract: Seawater usually contains sixty elements from the Periodic Table. The brine, rejected by a desalination unit, is a concentrate of all compounds contained by seawater. However, some of the elements are very scarce on land and/or are very expensive. There is thus a strong motivation for extracting these materials. Current practice in countries using large-scale desalination is to reject brine back to the sea. Increasing ecological objections are now being voiced since this rejection leads to a degradation of local fauna and flora. Extraction of materials and subsequent brine conditioning for surface storage would therefore be also another advantage for these integrated desalination plants, making them more environmentally friendly. This paper summarizes our preliminary investigations to achieve the above objectives. Elements of interest were first selected on the basis of several economic, physical-chemical and technical criteria. Research was then undertaken to elaborate a common extraction method. After several different solutions, the protocol finally retained comprises a first extraction of Phosphorus through purification by alum. The next step is the recovery of Caesium through an innovative liquid–liquid extraction approach, based on the use of Calixarenes. Indium is then recovered by another liquid–liquid extraction with the help of organic acids. In the final phase germanium and magnesium are extracted. The remaining solution is principally composed of sodium and potassium chlorides, which are separated by hot lixiviation techniques, using the different solubilities of NaCl and KCl. The protocol of extraction thus elaborated would now require exhaustive economic evaluation and experimental verification. These are currently in progress. [Copyright &y& Elsevier]

This paper summarises our recent investigations undertaken as part of the EURODESAL project on nuclear desalination, currently being carried out by a consortium of four European, and one Canadian, industrials and two leading EU R&D organisations.Major achievements of the project, as discussed in this paper are:

The code system, SEMER, was recently developed to evaluate the economic impact of various nuclear reactors and associated innovations. Models for nearly all fossil energy-based systems were also included to provide a basis for cost comparisons.Essentially, SEMER includes three types of model libraries: the global model, for a rapid estimation of various nuclear and fossil energy-based systems, the detailed models, for the finer cost evaluation of individual components and circuits in a PWR type of reactor and the fuel cycle models, for PWRS, HTRs and FBRs, allowing the cost estimations related to all the steps in the nuclear fuel cycle, including reprocessing and disposal.This paper summarises our on-going investigations on new developments in, and on the validation of, the SEMER system.Details of the modelling principles, and the results of validation carried out in the context of an EDF/CEA Joint Protocol Agreement, are also presented.First results of this validation are highly encouraging: