by Will Davis
Early 1960’s artist’s concept for a commercial organic cooled nuclear power plant – right near a city. This isn’t far from what actually happened as we’ll see below. Concept art published by Atomics International.
The present re-examination of reactor principles tried in the past but for one or another reason sidelined has skipped a very significant principle: Organic coolant. This was an early idea which received a great deal of research and press during the great buildup of nuclear technology; today, it’s largely been forgotten. Let’s take another look!
1. Organic coolant was conceived early. According to E. F. Weisner of Atomics International (1) the idea of using a hydrocarbon fluid as either coolant, or coolant and moderator, in a nuclear reactor goes all the way back to the Manhattan Project of the Second World War years. While gas cooling (with graphite moderator) and water cooling (with water moderator) took over the lead of power reactor development after the end of the Second World War, an important meeting was held in August 1953 in Downey, California during which engineers first undertook serious consideration of hydrocarbon fluids for use in power reactors. Thus, the serious consideration of organic coolant (and moderator) dates from just about the time that pressurized water plants proved workable.
2. Organic coolant means great qualities. Because the kinds of organic materials (2) used for early reactors had low vapor pressures, the plants they would be used in could be designed to operate at very low system pressures. This removed a lot of the consideration about pressurized release of coolant and energy if there was a leak. Also, they could be operated at fairly high temperatures. This combination of features meant that organic cooled plants could provide superheated steam (since the coolant could operate safely up to about 700F),
by Will Davis