Nuclear applications, membrane technology

It has been demonstrated that membrane separation processes can be successfully used in the removal of radioactive substances, with some distinct advantages over conventional processes. Following the development of suitable membrane materials and their long-term verification in conventional water purification, membrane processes have been adopted by the nuclear industry as a viable alternative for the treatment of radioactive liquid wastes [1]. In most applications, membrane processes are used as one or more of the treatment steps in complex waste treatment systems, which combine both conventional and membrane treatment technologies. These combined systems have proved more efficient and effective for similar tasks than conventional methods alone. 

Some research groups worldwide are currently working on the application of membrane technology to the treatment of radioactive liquid wastes with different levels of activity, from low to high activity waste. Research is mainly focused on wastes from the nuclear industry. However, the nuclear industry is not the only source of radioactive wastes medical and research applications of radioisotopes also generate radioactive wastes. 

Since 1995, the Chemical and Nuclear Engineering Department of the Polytechnic University of Valencia in Spain has been working on the application of membrane technology to the treatment of low and medium level radioactive liquid wastes. In this chapter, we describe two practical cases of radioactive liquid waste treatment using membrane processes the treatment of Cs-contaminated water generated after a radioactive incident in a stainless steel production factory, and the treatment of 1 liquid wastes from nuclear medicine services at hospitals. 

For application of membrane contactors in nuclear science and technology, snch processes like MD and membrane extraction-stripping were tested. A very important part of research in this field was devoted to liqnid membranes that also employ membrane contactors to form snpported liquid membranes (SLMs) [130],... 

Radiation-based technologies are employed for the development of a new class of materials, namely, stimuli-responsive polymers and membranes that can be applied in nuclear science and technology. It is foreseen that temperature-sensitive or pH-sensitive membranes can be used in a variety of novel applications, including separation processes in the nuclear field, for the recovery of uranium from seawater. 

Andalaft, E., Vega, R., Correa, M., Araya, R. and Loyola, R 1997. Zeta potential control in decontamination with inorganic membranes and inorganic adsorbents. In Treatment Technologies for Low and Intermediate Level Waste from Nuclear Applications. Final Report of a Coordinated Research Programme 1991-1996. IAEA-TECDOC-929, pp. 15-32. IAEA Vienna. 

This chapter is concerned with the study of kinetics of solute transfer at free liquid/liquid boundaries. This process has found many applications in separation science [1] with developments in hydrornetallurgy (e.g. Cobalt/Nickel separation), nuclear fuel reprocessing, pharmaceutical industry and supported liquid membrane technology. indexTransfer kinetics... 

In summary, the development of inorganic membranes was initially oriented towards uranium enrichment which is still by very far their most significant application. Some of the key participants involved in the nuclear programs further developed them into cross-flow filtration membranes. The recent years have seen the start of a much broader exploration of the manyfold potentialities of inorganic membranes, both in terms of materials and applications. Thus, a multifaceted new field of technology is emerging. 

The successful application of the sol-gel route has been realized in the International technological practice of many branches of the industries—electronics, optics, construction of engines, nuclear energetics, chemical, and food industry equipment. Among these materials are ferro-, piezo-, and dielectrics, solid electrolytes, refractory materials, membranes, protective and decorative coatings, and also films with special optical and electrophysical properties, like hightemperature superconductors. 

Continuous development of membrane processes applied in nuclear technologies is of considerable interest. Implementation of new membrane materials with high chemical and radiation resistance, and new module designs allow spreading applications of membrane processes into different fields of nuclear industry. The main barriers in the use of membrane methods are the... 

This chapter presents an overview of different membrane processes and a description of all of the chapters presented in this edition. Chapter 2 focuses on updated information of utility to UF and NF membrane research and development, particularly in the preparation of new types of UF/NF membranes with improved performances. Chapter 3 presents a comprehensive review on RO membrane, the latest developments in the field, important installations demonstrating this technology, and future scope of RO processes. Chapter 4 presents the potential of membrane contactors, especially hollow fiber contactors in the field of chemical and nuclear industry along with their applications, performance, and current challenges faced by indnstry. This chapter also gives an introduction to membrane contactors, their principles of operation and associated mechanisms (where chemical reactions are involved), and fntnre scope of these contactors. 

Zakrzewska-Trznadel, G., Harasimowicz, M., Chmielewski, A.G., Membrane processes in nuclear technology— Application for liquid radioactive waste treatment, Sep. Purif. Technol. 22-23, 617, 2001. 

The importance of the aforementioned topic may be realized as Bhabha Atomic Research Centre had organized a 3-day Theme Meeting on Membrane Sqtaration for Fuel Cycle Applications at Bhabha Atomic Research Centre (BARC), Mumbai, India, on September 16-18,2013 [5]. Some of the important papers presented by national and international researchers in this conference relevant to radioactive waste processing are inclnded in this chapter. Also, the latest Encyclopedia of Membrane Science and Technology focused on special importance to nuclear waste processing and described... 

A.K. Pabby, Hollow fiber membrane based technology and pressure driven membrane processes in nuclear fuel cycle Current status and challenges, in Proceedings of Theme Meeting onMembrane Separation for Fuel Cycle Applications, BARC, Mumhai, India, Septemher 16-18, 2013, p. 8. 

It was concluded that the SMM-modifled membranes could be used effectively for rejecting the radioactive compounds in water solutions. Moreover, the radioactivity of the SMMs membranes after 4 h DCMD experiments was substantially lower than that of the commercial membrane TF200 (Table 1.4), suggesting a smaller adsorption of the radionuclides on the SMM-modifled membrane, which can be regarded as an advantageous property and important for further application in nuclear technologies. 

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