Radioactive parts produce warmth as they decay. Nuclear vegetation draw energy from this course of, and sometimes stabilize the temperature with water. However throughout an influence outage, H2O—which wants pumps to circulation—can’t all the time stop meltdowns. Molten salt reactors, which as a substitute management warmth with melted lithium and potassium fluorides, have a fail-safe: If the electrical energy dies, a plug will soften, inflicting the salts to seep down a security drain and solidify across the uranium, stopping overheating. After a decades-long lull in improvement, nations from China to Denmark are constructing new molten salt reactors. Right here’s how they work.
1. Reactor vessel
Uranium floats in a stabilizing tub of melted fluoride salts inside this container. Because the radioactive atoms break up aside, their fission steadily heats the vessel to 1,300 levels Fahrenheit, the approximate temperature of magma.
2. Main warmth exchangers
Tubes on both aspect of the reactor vessel switch the warmth to intermediate pipes, that are full of clear molten salts. The uncontaminated substance can carry vitality with out producing any further radioactive waste.
three. Coolant salt pumps
These pumps transfer the clear salts within the warmth exchangers away from the radioactive reactor vessel and towards a steam generator housed in a separate constructing. This limits the hazardous materials to a single, remoted location.
four. Steam generator
The searing salts warmth water into steam, which spins a turbine to provide electrical energy. In a single hour, a molten salt reactor could possibly crank out 500,000 kilowatts, sufficient to energy 45 U.S. households for a whole 12 months.
5. Drain tank
Contaminated reactor salts and radioactive gases filter right into a waste-disposal system. These supplies stay hazardous for under tons of of years—in contrast with tons of of 1000’s for conventional reactors’ byproducts.
This text was initially revealed within the January/February 2018 Power subject of Widespread Science.