System for dismantling installations present in a building, and process for using this system

摘要

A system for dismantling installations present in a building (10) kept at a reduced pressure by virtue of a ventilation system. A hood (28) is brought above the installations to be dismantled. During the dismantling a fan (36) makes it possible to extract in the middle part of the hood (28) the air containing the aerosols due to the dismantling operations. After purification, a proportion of the gases is returned to the hood (28) and flows out at the periphery of the latter, thus creating a dynamic confinement region around the said installations. Another proportion of the gases is sent to the extraction pipework (18) in order to maintain the desired reduced pressure inside the building (10), the air entry (15) of the latter having been gradually shut off. Application to the dismantling of nuclear installations. IMAGE