ZIRNOX

The ZIRNOX GCR (gas-cooled reactor) is a type of nuclear reactor in HBM's Nuclear Tech Mod that serves as a more advanced/realistic alternative to the generic Nuclear Reactor (which has been deprecated since and replaced with the Research Reactor).

The ZIRNOX is a gas-cooled (CO²), Graphite-moderated, Boron-controlled reactor. It can be used with natural Uranium as fuel and as a result, there is no need to build expensive machines to enrich the Uranium into MEU Fuel. It doesn't release Environmental Radiation while running because it is fully encased automatically.

It can also run on higher level fuels but the maximum temperature is highly limited and no matter the configuration of the rods or the fuel itself, the power-production is limited. The ZIRNOX can be used to breed Thorium-232 into Thorium fuel, which when depleted can be used to get Uranium-233, a fissile Uranium isotope, not to be confused with Uranium-235.

The depleted fuel can be reprocessed, and depending on the original fuel, will yield different useful isotopes and small amounts of nuclear waste.

The ZIRNOX only accepts special ZIRNOX fuel rods, which need Zirconium to be crafted.

It is useful for breeding isotopes for later use in it or the RBMK. The fissile isotopes obtained through reprocessing of spent nuclear fuel can also be used in Nuclear Weapons, such as Nuclear Warheads for missiles.

### Fuel Reprocessing

*See: Guide: Recycling Depleted Fuel for more information*

Depleted fuel can be taken out of the reactor and turned into depleted fuel items.

The spent fuel pellets then need to be cooled down in a spent fuel pool drum, so they can be further processed. After cooled down, they can be put in a centrifuge and separated into different isotopes and nuclear waste.

For example, processing depleted natural Uranium fuel will give you: 1 Uranium-238 nugget, 2 Reactor-Grade Plutonium nuggets, 1 Plutonium-239 nugget and 2 Tiny piles of nuclear waste.

It can also be used to make fusion fuel by inserting ZIRNOX Lithium Rods next to normal fuel. Lithium will eventually breed into tritium (Hydrogen-3) which can be used in fusion reactors and other advanced machines.

Recipes can be viewed using Not Enough Items (NEI) for convenience.

### GUI and Usage

The GUI of the ZIRNOX is very simple.

The entire left section of the GUI are fuel slots. There are 24 fuel slots in total. Multiple types of fuel can be used at once but breeding rods by themselves won't sustain a chain reaction, since they're not fissile. If you have breeding rods in your reactor (Ex.: Thorium), always make sure that you have actual fuel next to them, or else they won't transmutate.

Fuel rod depletion is not even, depending on its position. Except for breeding rods, fuel rods placed directly horizontally or vertically adjacent to eachother will increase their decay value, decreasing the lifetime and increasing the heat produced. Usually, the innermost rods deplete significantly faster than their outermost counterparts. This is because the inner hull of the reactor is not lined with neutron reflectors, so neutrons from the outermost rods will be absorbed, resulting in an imbalance of neutrons and depletion rates in favor of the innermost rods.

The two gauges at the top are the most important. The left gauge shows the temperature and the right one shows the pressure. If either of these reaches the max value the reactor will explode, contaminating and scattering radioactive debris over a large area.

The ZIRNOX uses Carbon dioxide as its coolant. The CO2 gauge can be seen as the leftmost gauge of the 3 gauges found at the bottom of the GUI. The reactor has an internal CO2 buffer of 16,000 mB. While the reactor is running, it does not consume CO2, however CO2 expands with heat, which increases pressure, so it can be vented using the large red valve under the temperature and pressure gauges, which decreases the pressure but increases the temperature due to reduced cooling, thus power. Keep a balance for the fuel you use.

The CO2 coolant transfers the heat of the core to water and makes super dense steam. The reactor consumes water while running, although not very much. A single infinite water barrel can do the job, assuming an open circuit. 1 or 2 steam condensers are all that is required for a closed circuit. From the row of 3 gauges the right one shows water levels. Make sure you always have water in the reactor otherwise it will meltdown and explode.

The middle gauge shows super dense steam levels inside the reactor buffer. Ideally the steam turbines can pull all steam from the reactor and leave this 8,000 mB buffer empty. If you find that it quickly fills with steam, then your steam or cooling loop might be clogged up somewhere. Reaching the maximum steam buffer will also result in an explosion from the steam pressure.

The control rods can be extracted or inserted using the red button immediately left of the temperature gauge. There are no inbetween states for ZIRNOX control rods. The reactor is either ON or OFF.

### Meltdown

If either the temperature gauge or the pressure gauge reaches the top value the reactor will explode.

The ZIRNOX meltdown is similar to an RBMK meltdown in that it releases large amounts of radiation, contaminates several chunks surrounding the reactor, and spews radioactive debris that needs to be picked up. After the meltdown the reactor releases a so called "Meltdown Gas" and it will linger around the reactor if the remains of the structure are not removed. Once you remove the burning reactor, the remaining meltdown gas will slowly decay. Meltdown gas is highly radioactive and produces fallout when present. This fallout can be processed in a SILEX to get dust and small amounts of different rare isotopes like Cobalt-60, Technetium-99 and Gold-198. Though, there are far easier and cheaper ways to get fallout.

## Trivia

* The Zirnox is inspired by the British Magnox GCR, which functions effectively the same way.
	+ The only difference being that the Magnox used a Magnesium-Aluminium fuel rod cladding and the Zirnox uses a Zirconium-Beryllium cladding, hence the names.