SECURE reactor

The SECURE reactor Is basically a pool type PWR. The entire primary circuit. Including the steam generator, is located inside a massive, leakproof, practically indestructible pressure vessel that contains a large pool of borated water. 

In plutonium-fueled breeder power reactors, more plutonium is produced than is consumed (see Nuclearreactors, reactor types). Thus the utilisa tion of plutonium as a nuclear energy or weapon source is especially attractive to countries that do not have uranium-enrichment faciUties. The cost of a chemical reprocessing plant for plutonium production is much less than that of a uranium-235 enrichment plant (see Uranium and uranium compounds). Since the end of the Cold War, the potential surplus of Pu metal recovered from the dismantling of nuclear weapons has presented a large risk from a security standpoint. 

In reaction engineering, laboratory catal54ic reactors are tools or instruments to study how catalysts behave in some desired reaction. Quantitatively, the investigator wants to know how much of the desired product can be made per unit weight of catalyst, how much raw material will be used, and what byproducts will be made. This is the basic information needed to estimate the costs and profitability of the process. The economic consequence of our estimates also forces us to clarify what the rate limiting steps are, and how much transfer processes influence the rates, i.e., everything that is needed for a secure scale-up. Making the... 

Finally, the oxidation reaction has to been run under strict conditions of temperature, which are impossible to be operated in a batch reactor. Indeed, utility stream in the Shimtec reactor was heated to 47 °C, which first initiates the reaction, accelerates its kinetics, and then controls the temperature when the heat of the reaction is too important. In a batch reactor, working with such UF temperature is impossible because of security constraints. It would certainly lead to a reaction runaway. We now consider this question in the next section. 

Filtration of Liquids Depending on the specific electrochemical reactor type, the filtration rate of a liqnid electrolyte throngfi tfie separator should be either high (to secure a convective snpply of snbstances) or very low (to prevent mixing of the anolyte and catholyte). The filtration rate that is attained under the effect of an external force Ap depends on porosity. For a separator model with cylindrical pores, the volnme filtration rate can be calcnlated by Poiseuille s law ... 

Figure 6.9 Choosing the reactor to maximize security for multiple reactants producing by products. (From Smith R and Petela EA, 1991, The Chemical Engineer, No. 509/510 12, reproduced by permission of the Institution of Chemical Engineers).

The system parameter values depend on the particular application. When a house or a factory is to be monitored for intrusion detection, the cost of false alarms is relatively low. On the other hand, the financial and personnel cost of a false alarm is significantly higher when the perimeter security of a nuclear reactor is to be provided by deploying a SWSN to monitor unauthorized access. The cost of a false alarm might involve the transportation of special forces and/or personnel of related government agencies to the site, as well as the evacuation of residents in the surrounding area. 

For the purpose of this discussion, radiological materials that could be used in a terrorist attack are divided into three categories (1) bomb-grade nuclear material, (2) nuclear reactor fuel and associated waste products, and (3) industrial sources. Bomb-grade nuclear material includes concentrated plutonium and/or highly enriched uranium (>20% U-235) that may be used to build a nuclear weapon, assuming a terrorist group cannot or has not already secured an assembled weapon. 

The experiments were carried out on a semi-industrial fluidized bed reactor, illustrated in Figure 9.6, which shows four different sensor positions (A, B, C and D). Screw fittings were used to mount the sensors in order to secure optimal sensor pickup efficiency. Sensor location A is mounted onto an orifice plate on the main supply line of liquid urea to the reactor nozzles, following Esbensen et al. [5]. The sensors B, C and D are located on the wall of reactor chambers 1, 2 and 4, respectively. 

AECL has evaluated some of the basic information and development requirements in some detail (24, 25) and has outlined the type of fuel recycle development program which would be required. It would involve research and development of thorium fuels and fuel fabrication methods, reprocessing, demonstration of fuel management techniques and physics characteristics in existing CANDU reactors and demonstration of technology in health, safety, environmental, security and economics aspects of fuel recycle. 

Mark, J. C. 1993. Explosive properties of reactor-grade plutonium. Science Global Security, 4, 111-128. 

Depolymerization. Subsequent depolymerization of this lignin was carried out in a 500 ml magnetically stirred autoclave. A typical procedure for the experiments was to load the autoclave with 5 g of dry lignin (dried at 60°C overnight), 100 ml solvent, and 0-6 g sodium hydroxide. The bomb was sealed, secured onto its support frame, then the gas inlet, outlet, and pressure gauge were connected. After purging the reactor with nitrogen to remove air, the stirrer was set at 500 rpm and switched on. 

In order to secure a continuous quantitative analysis of the outlet gas mixture, including all the species necessary for the evaluation of the nitrogen atomic balance, namely NH3, NO, N02 (reactants), N2 and N20 (products), the gases exiting the reactor were analyzed both by a Mass Spectrometer (MS) (Balzers QMS200) and by a UV analyzer (ABB Limas 11HW) in a parallel... 

In our design considerations we have extrapolated the global rate expression for CO oxidation outside the conditions for which it was derived, and this extrapolation leads to erronous results. Experimental results on oxidation of CO in a flow reactor at varying pressure are shown in Fig. 13.3. The results clearly show that in the medium temperature range around 1000 K, an increased pressure acts to lower, not increase, the rate of CO oxidation. To secure adequate oxidation of CO, we would probably need to increase the postflame residence time in a high-pressure reactor compared to an atmospheric pressure reactor. 

The Flow Reactor In flow reactor experiments designed for chemical kinetic interpretation, the objective is to achieve a plug-flow situation, where composition and temperature are uniform over the cross section of the reactor. This condition may be approximated both in the turbulent [442] and the laminar [233] flow regimes. In the turbulent flow regime, a high linear flow rate secures negligible recirculation flow. Each element of gas reacts as it moves, with the characteristic time scale for heat and mass transfer by... 

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