In an announcement on Monday, an official at Iran’s Natanz enrichment facility said that Iran will ramp up their production of low-enriched uranium, aiming for a fourfold increase in their current rate of production.
At present, Iran is only enriching uranium to 3.67 percent, the level
needed to fuel the Bushehr Power Plant. The uranium is generally sent on
to Russia for the production of fuel rods. At previous production
levels, Iran was producing only a fraction of the fuel they need, and
this suggests that with increased sanctions they are looking for more
self sufficiency.
Because of the improvement of centrifuge technology since the P5+1 deal
began, Iran can increase this enrichment without violating the terms of
the deal. The withdrawal of a member (the US) from the deal, also
allowed Iran to withdraw from voluntary caps of uranium stockpile, which
they did recently.
Iran’s voluntary limit was 300 kg of low-enriched uranium, and with
higher production, along with US demands that Russia stop helping them
process fuel, its likely they will run up on that limit. This suggests
Iran’s announcement they were ending the voluntary stockpile cap was
done in anticipation of this new move.
Put that in your corn pipe and smoke it. Uncle Sham.
Can the centrifuge technology be improved to enhance the output of 3.67 % U235? Yes, as follows. The greater the rotational frequency (RPM) of the centrifuge tube the greater the degree of U235 enrichment at the axis of every tube because U235 is the lighter isotope. There are several factors which limit the tube’s RPM. One is the strength of the metal of which the tubes are made. Originally there was the idea of using the very strong titanium metal but that metal is corroded too fast by the UF6 gas used. The tubes are therefore made from aluminum alloys which produce an impenetrable thin layer of aluminum fluoride on the skin, hence the hullabaloo about the tubes for Saddam Hussein which were completely useless for centrifuges. Therefore, if a stronger alloy is developed and used, then a smaller number of faster spinning centrifuges can be used to produce 3.67% U235.
One of the Achilles heels of each centrifuge is the “pin” at the bottom on which a tube rests when in operation. Keep in mind that no mechanical contraption prevents a tube from falling sideways. Better pins may have been developed.
Then there is the counter-flow of UF6 into and out of every tube to multiply the enrichment of single tubes. Again, that system can always be improved.
Finally there is the electronic control of the whole “cascade” of tubes. That can always be improved to reduce “out-time”.
In summary, such improvements are always possible but these are never simple and need extensive testing.
I have deliberately left the simplest improvement for last. Suppose you have available a working cascade of a number X of tubes. At the given flow rate of Y liters of UF6 per minute in and out you steadily produce 3.67% U235. What will happen when you increase the flow by, say, 10%? The concentration of U235 of the product will drop below 3.67%! How can you avoid that drop? By adding more tubes to the cascade!