It works as simple as putting materials (one uranium, 4 depleted) in each reactor and pressing The Button. Then after two hours and a half reactors switch off and you have 4 re-enriched and one 53% spent uranium cell in each.
Whole thing is easily fit in one chunk, leaving no place to chunk-related bugs.
You can have any amount of reactors in the plant, just hook them up to same redstone input and keep them in the same chunk. Reactor tower
It works in following way. Each reactor has 2 chambers and completely submerged in water (24 cells).
It has +25 heat/sec when on and -25 heat/sec when off.
You can also put 12 reactor platings inside. This will prevent you from getting damage from reactors, and from reactors doing any damage in case of "explosion" (they just disappear and drop their contents). This way you don't have to bother with blast walls.
Also, platings can be used to measure temperature. Reactor should hurt you at 70% T, which is 8400 for two-chamber. Per each plate it increases by 70. So, reactor should damage you with 9 plates inside (T:9030), to have full breeding effectiveness.
Plant works in three stages - heat up, breed and stand by.
During heat up reactors work continuously, heating to ~9200 degrees in 6 minutes 8 seconds.
During breed stage reactors alternate 1 sec on/ 1 sec off. This keeps temperature on the same level.
When on Stand Buy reactors don't work and cools off for 6 minutes 8 seconds. After that they are ready to start again.
Schematics of plant is in attached picture N1. Red dots denote output sides of BatBoxes and MFEs. Black dots are mid-voltage sides of LVTs. All parts are horizontally oriented.
Besides visible parts there are two things you should do.
First, set BatBoxes A1 and B1 to "Emit when empty" (icon of redstone dust in top right corner, click three times)
Second, put 235 000 EU (235K to 236K will do, 230K to 240K at a stretch) in MFE A (top left on picture), and 2000 EU (anything from 1K to 39K will do, actually) in BatBox of the Flicker (top right on picture).
Now plant is in Stand By stage. B1 is empty, so it sends redstone directly to reactor, switching it off.
After putting materials in, press the button (top of the first picture, close view from the front on second and third pictures).
Then following things happen. EU will flow from A+A1 storages to B+B1 storages at a speed of 32EU/t (output limit of A1). Nothing will go back to A, because of redwire marked * on picture.
Redwire from A1 will block flicker, and redwire from B1 will be off, because it will not be empty. As a result, reactor will work continuously.
When A+A1 dry off, breed stage starts. Flicker is no longer blocked by A1, so it will keep reactors switched off half of the time.
Meanwhile, EU from B+B1 will flow into MFE A by a 1/27 wire. That means, of each 27 EUs leaving B1, only 1 will reach A, rest will be rerouted by LVT's marked as "1/27 slowwire" back to B+B1.
This gives 1.185 EU/t going in A, which you can confirm by EU-Reader.
When there is no more energy in B+B1, it is all in A, and we are now in Stand By stage again. Reactor will need 6 minutes to cool off, though. If you are not sure if reactor s are cool, put fresh Heat Dispenser on it - it should not get healthbar.
Now if you look inside reactor you will see something alike to fourth picture.
All following number are rounded to nearest integer. Heat up stage lasts for 235000/32 = 7344 tics. Reactor heats up at rate of 25/20 = 1.25 T per t. Therefore it heats up to 9180 T in 7344/20 = 367 seconds (6min 7sec). 3.4% of uranium is spent.
Breed stage lasts 27 times longer - 198288 tics. It is nearly a full Uranium cell cycle. But reactor works only half of the time, so only 49% of uranium is spent. Which gives around 53% total.
Redwire marked ** is not strictly necessary. Only thing it does is stopping annoying flickering during Stand By phase.
Redwire marked * can be done without too, but then energy from B+B1 will spill back to A+A1, increasing Heat Up time by 1/27 and T to ~9600.
LVTs marked Lock and Key do following. "Lock" will only transmit energy when A1 is not empty. So, it keep circuit in Stand By stage once it reaches it. "Key" is an alternative route from A to A1, but it is disabled by redstone torch. When you press The Button, torch will switch off for 1 second, letting 640 eu from A to A1 and kick-starting whole process.
CAN IT BE DONE BETTER?
Using Coolants and TDs in reactors is not worth it, as they increase heating stage by 100% (!) each, while giving only 1 cool at most.
On the other hand, if we vent off water during heat Up stage, we can make it nearly twice faster, reducing waste of uranium cell resources. May be it's what I'll try next.
Of what can be done with IC2 alone, it is nearly as good as you can theoretically get. All other methods include much more manual work per reactor per cycle, and are hardly more resource-effective. They can give more output per reactor, but each such reactor will cost more in materials than two Kurchatov reactors.
Breeding in 6-chamber reactor with only uranium and two depleted (giving 0 heating) is easy too, but you have twice less output for nearly twice more uranium and twice more expensive reactor. Not to mention you also have to bother with lava buckets too.
Of cause, if you use extra modes with tubes and such, you can get better results. It's hard co compete with "just put uranium ore in the chest" simplicity. But it feels a little bit like cheating, has roughly same effectiveness and is prone to bugs.
If 12 platings is used per reactor, or you are just confident, you don't need to separate reactors from outer world and each other with Reinfoced Stone. Then you can have them in tight 2x2 grid wall. You need 2 reactors to process one piece of ore, so if you find 1 ore each 10 minutes, you will need 30 reactors - 6 columns, 5 rows.