Reactor aqueous homogeneous

The simple batch reactor for homogeneous reactions is the most common type. From this kind of reactor, many kinetic data have been obtained. AU the reactants are charged in at the beginning of the reaction, with no mass transfer occurring until the reaction is complete. Examples of batch reactions are the ammonolysis of nitrochlorobenzenes, hydrolysis of esters, and polymerization of butadiene and styrene in aqueous suspension. These will be treated in more detail in later chapters. 

It is of interest that two additional papers on the subject of Reactor Dynamics in this volume include problems involving expansions in space dependent modes, first, the paper on Tem perature coefficients and stability by Harvey Brooks, and, second, the paper on System kinetics by T. A. Welton. Brooks is also interested in representations of the neutron density with the aid of a multi-mode analysis, but his problem is more complicated than that of this section because of feedback considerations. However, he confines his detailed analysis to a case in which the fundamental mode is dominant and where the effect of higher modes can be treated by a perturbation method. Welton s multi-mode analysis is peculiar to the aqueous homogeneous reactor and bears little resemblance to the corresponding problems treated by Brooks and this writer. Neither Brooks nor Welton appear to be interested in graphical representations of their results. 

V. Illustrative example. It is of interest to consider the application of the foregoing ideas to a particular reactor system. The present conception of a large aqueous homogeneous reactor has been chosen for this illustration, because of its simplicity, as well as technical interest. The design consists of a large cylindrical tank, with cold fluid entering at one end in an annular inlet stream, close to the cylindrical wall. Hot fluid leaves by a central circular outlet pipe at the same end of the tank. The volume of the tank is 4.3 X 1Q3 liters and 1.89 x 10 liters enter and leave per second. The fluid... 

D. K. Trubey, H. Moran and A. M. Weinberg, An Estimate of the Non-Leakage Probability for Bare Aqueous Homogeneous U-235 Reactors, ORNL memorandum CF 57-11-15 (195.7). 

The critical equation for an aqueous homogeneous / thermal reactor may be written as... 

Briggs, R.B., Swartout, J.A., 1955. Aqueous homogeneous power reactors. In Proceedings of the International Conference on the Peaceful Uses of Atomic Energy, Held in Geneva, 8—20 August, 1955, vol. HI, p. 496. 

These advantages stem partly from the fluid nature of the fuel and partly from the homogeneous mixture of the fuel and moderator i.e., an aqueous homogeneous reactor combines the attributes of liquid-fuel heterogeneous reactors with those of water-moderated heterogeneous reactors. If practical methods for handling a radioactive aqueous fuel system are developed, the inherent simplicity of this type of reactor should result in considerable economic gains in the production of nuclear power and fissionable material. 

However, many apparently formidable practical problems are associated with continued operation and maintenance of systems involving radioactive fuel solutions. It is believed, therefore, that extensive experience in a series of small- to large-scale reactor installations will be required to demonstrate the reliability of aqueous homogeneous reactors this will necessitate a long-range development program. In addition, the choice of... 

Single-fluid Two-region Aqueous Homogeneous Reactor Power Plant— Conceptual Design and Feasibility Study, US. EC Report NPG-171. Commonwealth Edison Company (Nuclear Power Group) and Babcock Wilcox Company, July 1957. 

P. R. Kasten et al.,. Aqueous Homogeneous Research Reactor-Feasibility Study, USAEC Report ORNL-2256, Oak Ridge National Laboratory, April 1957. 

Pacific Northwest Power Group, Aqueous Homogeneous Reactors. USAEC Report PNG-7, February 1956. 

T. B. Fowler and M. Tobias, Two-group Constants for Aqueous Homogeneous Reactor Calculations, USAEC Report CF-58-1-79, Oak Ridge National Laboratory, Jan. 22, 1958. 

R. B. Briggs, Aqueous Homogeneous Reactors for Producing Central-station Power, USAEC Report ORNL-1642(Dcl.), Oak Ridge National Laboratory, May 4, 1954. 

In an aqueous homogeneous reactor fuel solution, the water is decomposed by fission recoils, proton recoils, and fast electrons. The rate of hydrogen formation, in moles per liter per minute, can be expressed by the equation ... 

The remainder of this section is devoted to particular properties of reactor solutions which are of interest and to some properties of the vapor phase above reactor solutions which are important for aqueous homogeneous reactors. 

M. Tobias, Certain Physical Properties of Aqueous Homogeneous Reactor Materials, USAEC Report CF-56-11-135, Oak Ridge National Laboratory, Nov. 23, 1956. 

Removal of iodine from aqueous homogeneous reactors. It is... 

For return to an aqueous homogeneous reactor the decontaminated uranium would probably be precipitated as the peroxide, washed free of nitrate, and then dissolved in D2SO4 and D2O. Product thorium would be converted to thorium oxide by methods described in Section 4-3. 

S. E. Beall, Containment Problems in Aqueous Homogeneous Reactor Systems. U.S.VEC Report ORNL-2091, Oak Ridge National Laboratory, Aug. 8. 19.56. 

Circulating pumps. Pumps are reejuired in aqueous homogeneous reactors to circulate solutions and slurries at 250 to 300°C and 2000 psi pressure, at heads of up to 100 psi. The two main con.sidcrations for these pumi)s arc that they must be absolutely leak free and that they must have a long maintenance-free life. 

Feed pumps. High-pressure low-capacity pumps are required to feed solutions, slurries, and water into aqueous homogeneous reactor systems. In the HRE-2, which operates at 2000 psi, the requirements are for from 0 to 1.5 gpm of fuel solution, 0.25 gpm of purge water to the pressurizer, and 0.1 gpm of purge water to the circulating pump. 

The instrumentation and controls systems for aqueous homogeneous reactors are similar to those used in modem high-pressure steam power and chemical plants. However, problems attendant on radiation damage to insulations, the difficulty of performing maintenance or replacement operations, the requirement for the absolute leaktightness and the very high reliability of components necessary for safety and plant operability have required considerable development of special components. 

Aqueous Homogeneous Research Reactor— feasibility study. A... 

The general conclusion reached was that aqueous homogeneous reactors are potentially very low-cost plutonium producers however, considerable development work remains before large-scale reactors can be constructed. The major problem is due to the corrosiveness of the relatively concentrated uranyl sulfate solutions used in such reactors, which requires that all the equipment in contact with high-temperature fuel be made of titanium, or carbon-steel lined, or clad with titanium. The development of suitably strong titanium alloys, bonding methods, or satisfactory steel-titanium joints has not yet proceeded sufficiently to consider the construction of full-scale plutonium producers. Alternate approaches, such as the addition of Li2S04 to reduce the corrosiveness of stainless steel by the fuel solution (see Chap. 5), show promise but also require further development. 

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