초록 ▼

A cleaning process and water-based cleaning compositions effective for the removal of radionuclides, polychlorinated biphenyls, pesticides, herbicides, and heavy metals from surfaces of all types, more especially porous surfaces, surfaces that contain irregularities and microscopic voids into which

A cleaning process and water-based cleaning compositions effective for the removal of radionuclides, polychlorinated biphenyls, pesticides, herbicides, and heavy metals from surfaces of all types, more especially porous surfaces, surfaces that contain irregularities and microscopic voids into which contaminants may migrate and lodge thereby creating a substrate below the surface that must also be cleaned, and particulate surfaces. The cleaning blends and processes remove contaminants from porous and irregular surfaces to such a depth below the surface and into the substrate, and to such an extent, that the cleaned surface satisfies current regulations promulgated by the EPA and NRC relating to standards for decontamination. The process also allows sealing of cleaned surfaces, if desired, with an impermeable coating of a synthetic polymeric composition in order to retard subsequent migration of any residual contaminants to the surface.

대표청구항 ▼

A method for removing contaminants from surfaces and the substrates of such surfaces, including porous surfaces and surfaces with irregularities into which the contaminants may migrate or lodge, and particulate surfaces; the method comprising: (i) precleaning the surface with an aqueous precleaning

A method for removing contaminants from surfaces and the substrates of such surfaces, including porous surfaces and surfaces with irregularities into which the contaminants may migrate or lodge, and particulate surfaces; the method comprising: (i) precleaning the surface with an aqueous precleaning fluid comprising: from about 4 to about 10 wt. % sulfamic acid, from about 5 to about 10 wt. % hydrofluoric ammonium bifluoride, from about 2 to about 4 wt. % hydrochloric acid, about 1 to about 4 wt. % surfactant, about 6 to about 12 wt. % sodium citrate, about 2 to about 5 wt. % oxalic acid, about 10 to about 20 wt. % triethanolamine; and, optionally, about 1 to about 2 wt. % d-limonine; (ii) rinsing the precleaned surface with a fluid selected from the group consisting of water substantially free of ions and a solution of at least about 4 wt. % sodium citrate; (iii) applying to the rinsed surface an aqueous extraction fluid comprising: about 5 to about 8 wt. % surfactant, about 4 to about 8 wt. % of an emulsifier containing quaternary amines, isopropyl alcohol and glycerine, about 15 to about 20 wt. % ethylene diamine tetracetic acid, about 5 to about 10 wt. % ethylene glycol monobutyl ether, about 4 to about 8 wt. % of a chemical pH buffer agent, about 4 to about 8 wt. % triethanolamine, and about 4 to about 10 wt. % of a composition selected from the group consisting of ethylene-bis(oxyethylenenitrilo)-tetracetic acid, 1,2 diamino-cyclohexane-tetracetic acid, hydroxyethylene diamine tetracetic acid, nitrilotriacetic acid and sodium gluconate; (iv) allowing the applied extraction fluid to dwell on the surface for a time sufficient to penetrate into pores and microscopic voids or irregularities in the surface to extract the contaminant; and (v) washing the extraction fluid from the surface and producing a cleaner surface.