Zero-energy high-temperature reactor

ZENITH (zero-energy high-temperature reactor) was designed for research into high-temperature reactors ... 

ZENITH Zero-Energy High-Temperature Reactor... 

This condition was established for zero-order reactions, and is valid for highly exothermal reactions, resulting in a high temperature increase even for low degrees of conversion. In this criterion, beside the heat removal properties of the reactor, only the heat release rate at process temperature (q0) and the activation energy (E)... 

The energy requirement of the furnace is zero for this adiabatic reactor case since the reactor exit stream at maximum temperature can provide enough heat. The design of the FEHE and the amount of bypassing are determined by the reactor inlet temperature T-m. A temperature difference of 25 K is assumed for the hot end of the FEHE. The hot reactor effluent enters the hot side of the FEHE at the high-temperature limit of 500 K, so the cold-side exit stream is 475 K. If the specified reactor inlet temperature is less than 475 K, bypassing is used. A fairly low overall heat transfer coefficient of... 

Risley and Harwell were still at loggerheads with regards to the coolant. Risley remained opposed to the use of helium, whereas Harwell were adamant that carbon dioxide could not be considered. Harwell insisted on a design which would permit outlet temperatures of 1,000°C and which had power densities as high as those to be expected in a commercial HTR, which meant that the experimental reactor of 20 MW would need to use pressures as high as 20 atmospheres for the coolant gas. Treasury approval was sought for a zero-energy assembly, estimated to cost 4.6 million. ... 

TNA PRO AB 6/1658. High temperature gas-cooled reactors (solid, homogeneous) technical aspects. High Temperature Zero Energy Reactor Assemblies. Sir J Cockcroft, 21 June 1957. 

We now consider an adiabatic reactor of fixed sire or catalyst weight and investigate what happens as the feed temperature is varied. ITie reaction is reversible and exothermic. At one temperature extreme, using a very high feed temperature, the specific reaction rate will be large and the reaction will proceed rapidly, but the equilibrium conversion will be close to zero. Consequently, very little product will be formed. A plot of the equilibrium conversion and the conversion calculated from the adiabatic energy balance,... 

---