In a “Loss of Coolant Accident,” such as those which occurred in TMI and Fukushima, after minutes without effective cooling, reactor cores have overheated and melted, leading to leakage of radioactivity to the surrounding environment from the larger outer Concrete-Containment-Building. Causes include internal hydrogen explosions; steam over-pressurization of the Containment-Buildings secondary to emergency-infused cooling-water being flash-vaporized upon contact with an over-heated inner-steel reactor-vessel-core during a non-design basis accident (such as occurred at Fukushima), or possibly even from a single broken internal high pressure steam pipe (such as occurred at Chernobyl). The pressurized-steam and the volatile radioactive elements released into the pressure-vessel atmosphere, are either deliberately vented, or will escape the Containment Building through seams or cracks that are inevitable in current pressurized concrete-containment-building designs.

THE PROPOSED INVENTION ENABLES SIMULTANEOUS: (a) decompression of an over-pressurized external-concrete-containment building of a conventional nuclear fission power plant and (b) efficient cooling and condensation of escaping radioactive steam as a result of technically simple, uniquely effective, rapidly assembled, optimally-efficient linear, counter-current heat exchanger (comprised of tapered-thread-nipple-pipe-interconnected concentric stainless-steel tubes) which cools and condenses the escaping radioactive steam, with (c) resultant prevention of an over-pressure explosive destruction of the primary concrete pressurized containment building, and with (d), effective simultaneous, uniquely efficient, multi-modality HEPA-Ferrate Powder-Carbon-Block Filtration of the radioactive particulates and gases from the condensed and cooled escaping steam, with safe lead-shielded isolation of the escaping radioactive gases and particulates from this steam which become trapped within the Shielded, Robotically Exchangeable, Multi-Modality Cylindrical Radiation-Containing Cylindrical Filter-Canisters.

The multi-section, triple-concentric-pipe, linear “counter-current heat-exchanger”, optimizes the efficient cold-water-chilling-and-condensation of the steam which escapes through the heat-exchanger from the over-pressurized containment building, enabling more efficient chelation and filtered-removal of radioactive gases and particulates that escape with the steam, through the solenoid selection valves, into the multi-modality particulate-trapping, lead-shielded Filter-Canisters. The Linear Heat-Exchanger has several other potential Applications.

An electronically-controlled solenoid-valve at the point of its junction with the small-pipe inserted through the concrete containment and separate “selector” solenoid-valves at the distal-end (of the inner, smallest pipe) are computer-synchronized with the robotic-replacement of Filter-Canisters, through which the pressurized condensed-steam passes, leaving its radioactivity behind, trapped in the Cannister-Filters. The Canister-Filters are packed with inch-thick cylindrical, activated-charcoal solid-discs, inter-spaced with with alternate equal thickness layers of tightly packed Ferrate Powder, enclosed within ultrasonically edge-sealed, HEPA “pancake disc filters”. Ferrate Powder chelates and removes radioactive particulates from condensed water flowing through the central chilled steam escape pipe. Activated Charcoal Adsorbs Radioactive Gases such as Radon and Xenon-133.

Telsonic Ultrasonics manufactures a circular ultrasonic “Cut and Seal” device which ultrasonically creates a circular weld between plastic HEPA sheets. This circular weld of two parrallel HEPA sheets could encapsulate Ferrate Powder, thereby creating tight-fitting ”Powder-Filled HEPA “pancake-filters” whose outer-circumference tightly fits the diameter of the inner-surface of the Containment-Canister, to effectively seal passage of the radioactively-contaminated water through the radiation-absorbing powders within the HEPA-Filter-Pancake-Discs. The robotically interchangeable Filtrer-Canisters can be fabricated using available conventional materials such as standard aluminum or plastic containers, externally-shielded with lead.