Traveller11,
You did a great job of explaining and I think I have a very good idea of what is happening and how. Perhaps, I oversimplified my thoughts on the equipment, but the combination of the materials required (to withstand the reaction of the leach) and the necessary design to withstand the 60 PSI make this something that would be very difficult for a hobbyist refiner to build. Personally, if I had one, I would like for there to be a significant safety margin built into the pressure retention part. I simply cannot imagine what an explosion with HCl and chlorine gas would be like. However, if there was no open space in the rotating cylinder, there would not be much of an explosion. A company I used to work for used many aluminum castings. Sometimes, one would come through where the metal was porous and couldn't be used. The technician would seal both ends of the cylindrical casting. Then, it would be ALMOST filled with water. Next, he would submerge it into a tank filled with water and pressurized it with compressed air. If the casting was porous, air bubbles would escape into the tank and rise as the casting was rotated. With most of the casting filled with water, there was very little room for the air. If there would have been a catastrophic failure, there wouldn't have been much air to release and explosively expand. Had one failed, it could have blown anywhere on the casting, so the failure point could have been on top, on a side, or on the bottom, but it was ALWAYS under water. The air pressure was most likely well below the failure pressure since they were only looking for pin hole leaks. Still, the idea of chlorine and HCL under pressure demands much respect.
In a way, I'm sorry about the reactor part of the thread. It isn't truly on topic, but I thought it was interesting and would be thought provoking. NOONE on this forum can honestly say they aren't interested in science and learning. If you look at the reactor, the core was cube (3 feet on a side) made up of fuel RODS approximately 1.375 inches in diameter and the Uranium was enriched to somewhere between 15 and 30% (sorry, I just can't remember the details). For the sake of argument, lets say the top of the reactor was 9 feet below the surface of the water. The byproducts, without a stream of water blowing them sideways had to travel a total of 9 feet vertically to the surface. Now, turn on the pump and blow a stream of water across the top of the reactor. Instead of travelling vertically, the heated water is travelling with both a vertical component AND a horizontal component. Again, I don't recall the actual numbers, but to make it easy, let's say the water jet was pushing from left to right with a velocity that will blow the water off to the side whereby once it reaches the surface, it has travelled 12 feet horizontally. Looking at these numbers, we have a triangle with a horizontal side of 12 feet and a vertical side of 9 feet. This is a classic 3-4-5 triangle. While the byproducts move 9 feet vertically, they are moving 12 feet horizontally. But the total distance travelled is neither 9 feet nor 12 feet, but 15 feet. The byproducts are moving along the hypotenuse of the triangle. It is still only 9 feet vertically, but with the 12 foot horizontal component, it works out to a total distance travelled is 15 feet. Nothing adds to the vertical speed. The pump merely adds a 12 foot horizontal component. This is an oversimplification, because we are talking about heat, velocity, distance, and the water medium. The true path is not a nice straight line. The water from the jet will spread out and the water rising from the core cools down as it intermixes with the rest of the water in the reactor due to turbulence. The actual numbers are not important, it's the idea or concept that I was trying to illustrate. A hot air balloon on a day with a crosswind might have been easier to visualize.
In the real world of power production, reactor cores are usually cubic and depending on power produced, some are 12 feet on a side. The fuel is formed into cylindrical pellets approximately 0.375 inches in diameter with both ends concave to allow for thermal expansion. (The enrichment of the uranium is very low. It used to be about 3% to 5%, but I think it is slightly higher now. The higher enrichment means you can run the reactor longer between refueling and therefore have less down time.) The fuel pellets are sealed in zirconium clad tubes. The cladding restricts the maximum temperature the reactor can reach safely. Get it too hot and the zirconium will come off. This is not a good thing. Then the tubes are arranged into bundles. Before they go into the reactor, you can actually walk right up to them without any danger. They are closely inspected visually before being loaded into the core. After they have been in the core and have produced energy, they become dangerous as the uranium has changed into other products. We had a discussion about this at work one day, and even the smartest people in the room weren't sure of the answer. The question was: "If you set a used fuel bundle in the center, of a football stadium on the 50 yard line, could you run fast enough to touch it before you died? Or, would your blood boil before you got to it? We could never really figure that one out. We knew the company wouldn't let us borrow a used fuel bundle, and no one would volunteer as a runner.
