METHOD AND COMPOSITION FOR REMOVING DEPOSITS

• Main Authors: VARRIN, ROBERT D, LITTLE, MICHAEL J, ANDERSON, CARLY E
• Format: Patent
• Language: English; French
• Published: 28.04.2020
• Subjects: BLASTING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; CLEANING; CLEANING IN GENERAL; CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE ORHEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; HEAT EXCHANGE IN GENERAL; HEATING; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; MECHANICAL ENGINEERING; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; PERFORMING OPERATIONS; PREVENTION OF FOULING IN GENERAL; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE; WEAPONS

The present invention provides methods and compositions useful for conditioning and removing solid deposits that have formed on or otherwise accumulated within one or more components including, for example, scale formed within a steam generating system. The aqueous cleaning compositions incorporate one or more quaternary ammonium hydroxides characterized by pKa values no less than about 13.5. These quaternary ammonium hydroxides may be used alone or in combination with one or more additives including, for example, chelating agents, reducing or oxidizing agents, pH adjustment agents, surfactants, corrosion inhibitors, complexing agents, dispersants and combinations thereof. La présente invention concerne des procédés et des compositions utiles pour traiter et éliminer des dépôts solides qui se sont formés sur ou accumulés dans un ou plusieurs composant(s) comme, par exemple, le tartre formé au sein d'un système de production de vapeur. Les compositions nettoyantes aqueuses intègrent un ou plusieurs hydroxyde(s) d'ammonium quaternaire caractérisé(s) par des valeurs pKa non inférieures à environ 13,5. Ces hydroxydes d'ammonium quaternaire peuvent être utilisés seuls ou en association avec un ou plusieurs additif(s) comprenant, par exemple, des chélateurs, des agents réducteurs ou oxydants, des tampons, des tensioactifs, des inhibiteurs de corrosion, des agents complexants, des dispersants et leurs combinaisons.