Nuclear heating

Fypass Flow Effects. There are several bypass flows, particularly on the sheUside of a heat exchanger, and these include a bypass flow between the tube bundle and the shell, bypass flow between the baffle plate and the shell, and bypass flow between the shell and the bundle outer shroud. Some high temperature nuclear heat exchangers have shrouds inside the shell to protect the shell from thermal transient effects. The effect of bypass flow is the degradation of the exchanger thermal performance. Therefore additional heat-transfer surface area must be provided to compensate for this performance degradation. 

M. M. El-Wakil, Nuclear Heat Transport, American Nuclear Society, La Grange Park, lU., 1978. 

MHD efforts in many countries, including the United States, have declined substantially, in Russia because of lack of funds and in general because the high costs envisioned in setting up a full-scale power station. If funds become available to set up full-scale power stations and with the advent of high temperature nuclear heat sources, the many advantages provided by MHD may be realised. 

In Fig. 7.68 the oxidising and sulphiding potentials of four different atmospheric environments, i.e. conventional coal combustion (A), fluidised bed combustion (B), conventional coal gasification (C) and coal gasification using nuclear heat (D), are shown on the thermochemical phase stability... 

Effects of nuclear heating. Both out-of-pile loop experiments and in-pile reactor operating measurements are available. The rod bundle data obtained in an operating reactor (Farmer and Gilby, 1971) agree with those obtained in an out-of-pile loop, as shown in Figure 5.63. 

Steam Methane Reforming with Nuclear Heat Input... 

Nuclear energy can produce hydrogen in several ways (1) nuclear heated steam reforming of natural gas, (2) electrolysis of water using nuclear power, (3) HTE using minor heat and major electricity from nuclear reactor, and (4) thermochemical splitting of water using... 

Hydro power (%) Wind power (%) Geothermal (%) Nuclear (%) Heat (coal, gas) (%) Hydro power (MWh km ) Total (MWh km )... 

The reactor core, the source of nuclear heat, consists of fuel assemblies and control rods contained within the reactor vessel and cooled by the recirculating water system. A 1,220-MWe BWR/6 core consists of 732 fuel assemblies and 177 control rods, forming a core array 16 feet (4.8 meters) in diameter and 14 feet (4.2 meters) high. The power level is maintained or adjusted by positioning control rods up and down within the core. The BW R core power level is further adjustable by changing the recirculation flow rate without changing control rod position, a feature that contributes to excellent load-following capability. 

The most effective method of SNG production with an HTGR is the stcam-carbon reforming process in which superheated steam reacts with pulverized coal to form methane-rich SNG. A system for accomplishing this process is shown in Fig. 24. In this system, an intermediate heat exchanger (1HX) has been used to isolate the nuclear heat source from the process steam, thus allowing the use of conventional equipment for... 

Investigation of Radiation Effects Problems in Nuclear Heat Exchanger Rockets , Rept GD-FZK-137, Contract NAS 8-1609, General Dynamics, Fort Worth (1961) 91) Y.K. Roots... 

High temp (500-1000 C) using nuclear heat source... 

The first reaction takes place spontaneously at temperature range of 300-500°C, while the second takes place at temperature range of 750-850°C in the presence of catalyst. Here, the HTGR is uniquely qualified to produce the nuclear heat necessary to drive the intensive endothermic high temperature reactions of H2S04 decomposition to completion. 

Oil/fuel industry Upgrading of bitumen from oil sands using hydrogen produced by the nuclear-heated steam reforming of a portion of the product. 

In the intermediate term, nuclear-heated steam reforming of natural gas could be utilised, using medium-temperature reactors, in spite of some carbon dioxide emissions, because of its advantages in economic competitiveness and in technical feasibility. Also, high-temperature reactors could be used to carry out high-temperature steam electrolysis, with higher conversion efficiency and fewer materials problems. 

The application of this method is shown in Figure 5, where hydrogen is produced by the nuclear-heated steam methane reforming (using a sodium-cooled reactor and natural gas), and then this hydrogen is converted into electricity in the alkaline-type fuel cell. 

As the synergistic hydrogen production process using natural gas and nuclear heat is efficient and economic, and also the subsequent electro-chemical conversion of hydrogen into electricity in an alkaline fuel cell is efficient, electricity generation by combining these two processes have the following possibilities ... 

A preliminary evaluation shows the electricity generation efficiency of this process is about 60% (based on the sum of natural gas heat and nuclear heat), which is comparable to a natural gas advanced combined cycle power plant. 

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