The purpose of this procedure is to indicate the steps to be followed in taking the plant from the cold iron condition to the condition of decay head removal. The normal startup from the decay heat removal condition will proceed according to SOP 1101, Part II.
[The significance of being filled solid with water may refer to the SL-1 accident, where a reactor which was only partially full accidently went prompt critical, killed three people, and the water hammer from the partially full vessel bounced the 26,000 pound reactor vessel off the ceiling].
[A letdown cooler is a water to water heat exchanger, cooled by CW water, which cools the normally 508F primary system water to about 115F before it goes into the purification system. When the reactor is shut down, the chain reaction stops, as does most of the heat output. However the decay products are not stable, and continue to decay on their own, and emit heat. Immediately after a shutdown, the maximum decay heat will be nearly 12 megawatts (this is an 80 megawatt (thermal) reactor), it will drop off quickly, to the point that it can be handled by a single letdown cooler at 10 gpm.]
[The purification system removes anything which is not water from the primary system water. The neutron flux in the core does not affect water, however anything dissolved in it can be activated by the neutrons, and become radioactive. This reduces that radiation hazard.]
There are a total of four primary pumps, only a single one is needed to keep the coolant going through the core. If the PS is cool enough, and completely depressurized, a portable pump can also be rigged to circulate the primary coolant, and all four primary pumps may be shut down. See POS RC]
[When the reactor is shut down, it is left with the scram signal asserted.]
[The desurgers are an expansion tank immediately after the SL charge pumps. The heaters boil the water in the desurger, to maintain a compressible bubble of steam in the desurger, to even out the pressure pulses from the pistons of the SL charge pumps.]
[As the system's temperature increases, the volume of the water increases, and that overflow has to go somewhere. Specificly, PD-T2 and PD-T3.]
[The normal level of water in the pressurizer is 27 inches, with the top of the tank full of steam. The pressure in the system is controlled by heating the water in the pressurizer with electric heaters. So the hottest part of the system is the pressurizer, and that is the only bubble of gas in the primary system.]
[The SL charge pumps are designed such that the water in the buffer seals leaks into the reactor vessel. The highest pressure in the system is immediately after the SL charge pumps. When the system is starting up, the PS pressure is far lower, and the charge pumps can over-shoot.]
[Valve SL-9V is the pressure regulation valve for the SL water, and designed to operate at 1750 psig or so. Right now the PS pressure is 55 psig, so the bypass valve is opened to keep the pressure of the SL water closer to PS pressure.]
[Primary pump flush flow (from SL) is on when the temperature of the PS is to be changed more than 30F, or if the pump is off for more than 30 minutes. I believe it is intended to make sure that if pump seals are going to seep, the flow will be into the PS. PS-P1 does not have flush flow.] Note: As the primary pressure increases, it will be necessary to throttle SL-60V in order to maintain the SL-9V controller "D" chamber reading in mid-scale position.
[The primary coolant is deionized water, the purification system consists of ion exchange resin beds, just like one can find in a water softener or laser cooling system, which will extract any ions from the water, followed by several filters to prevent the resin beads from getting into the primary system. There are three sets of ion exchangers and filters, normally two are used and one is standby, but a single is sufficient to operate the reactor.]
[Makeup water is water added to a boiler to make up for losses elsewhere in the system.]
[The SL system has two centrifugal booster pumps, which feed three reciprocating charge pumps, which get the water to in excess of 1750 psig, and inject it into the buffer seals around the control rod pass through on the reactor pressure vessel such that the water will leak into the reactor vessel. Generally one booster pump, and two charge pumps are operated, with the third charge pump in reserve (switched off).]
[The interior of the containment vessel is cooled by the CC subsystem, an air to water heat exchanger cooled by CW water. It intends to get the containment vessel down to 115F.]
[The containment vessel is within the reactor compartment. A slightly negative air pressure is maintained in the reactor compartment, so air leaks in, instead of out.]
[There is a comment in the film documenting the construction of the Savannah noting that it has no funnel. This is not entirely true... The Savannah has an oil fired boiler and multiple diesel generators for auxiliary power and reactor startup. The funnel is telescoping and is located above the docking bridge at the stern. There is also a vent pipe for the reactor (WL) on the mast immediately forward of cargo hold 4.]
[Fresh water is needed for flushing the sampling sink.]
[MG is Motor Generator. At this time, the cheapest most reliable way to convert AC to DC and vice versa is a motor mechanically driving a generator.]
[The nuclear instrumentation has its own independent battery bank, which will run it for 3 days.]
[Buffer seal water cools the O rings around the control rods. They are made of buna-N, and will be damaged above about 300F.]
[This tests that the primary pumps will automaticly shut off if the valves in the primary system are closed. The startup checks exercise most if not all of the safety interlocks.]
[A slidewire is an analog position indication sensor.]
[The letdown coolers may be configured to remove decay heat using a portable pump connected to fittings in the containment vessel, instead of the primary pumps. The pump and hoses must be disconnected before significant pressure is achieved. See POS RC ]
NOTE: Temperature increase in the Primary System is limited to 35F per hour, and in the Pressurizer it is limited to 70 F per hour.
[If the system is warmed up too quickly, the metal on the inside of the various pressure vessels will expand more than the metal on the outside of the vessel and cause thermal stress. At 35F per hour, there is enough time for the pressure vessel walls to warm up through their entire thickness.]
[Blowdown is intentionally venting steam or water from a boiler, to remove contaminants.]
[Nominal PS pressure is 1750 psig, 1830 psig keeps SL pressure above PS pressure.]
[The steam generators consist of a cylindrical tank mounted above a second U shaped tank. The two tanks are connected together with several vertical pipes (called downcomers). The U shaped tank has many U shaped stainless steel tubes carrying PS coolant. The water surrounding the tubes will boil, and steam will flow up the downcomers. The top tank is called the steam drum. See Steam Drum.]
26. Clear and secure the secondary shield area.
[BF3 refers to one of the three types of sensors for measuring the reactor neutron flux.]
[Vacuum refers to the main condenser. Since the condenser is going to condense all of the steam, and there is no air in the system, the pressure in the condenser will be below atmospheric pressure. The condensed steam will then be feed water, and is pumped back into the steam generator by the feed water pumps. Losses will be made up for by adding makeup water.]
[DFT is deairating feed tank, probably in the BF system.]
[T.G. is turbo generator, "turbo" just means turbine driven. The two turbo generators are rated at 1500 KW each, bus voltage is 450VAC three phase.]
[Quantichem is a continuous water quality monitoring device. It checks for contaminants in the feed water, and monitors ph.]