Abstract: The invention describes a method of reducing or preventing the growth of microbes on the surface of an object, wherein the object is of such material that it can act as a working electrode. The method comprises the steps of providing a counter electrode, and a reference electrode. The object is used as the working electrode. Electrical current is passed through the working and counter electrodes. The current through the counter electrode is varied such that the electric potential of the working electrode is constant relative to the electric potential of the reference electrode. Also described is an apparatus for reducing or preventing microbes on an object using a potentiostatic device.

Abstract: The corrosion resistance of stainless steel anodes for use in alkaline water electrolysis was increased by immersion of the stainless steel anode into a caustic solution prior to electrolysis. Also disclosed herein are electrolyzers employing the so-treated stainless steel anodes. The pre-treatment process provides a stainless steel anode that has a higher corrosion resistance than an untreated stainless steel anode of the same composition.

Abstract: A method for inhibiting corrosion in at least one required region of an elongate metal structure, comprising applying a high-frequency electromagnetic signal to the structure in a manner such that a voltage standing wave is established in the structure with a corrosion-inhibiting potential at the required region(s) of the structure. The method is advantageously applied to an oil well riser pipe, to inhibit corrosion of the external surface thereof in the vicinity of an oil production zone.

Abstract: This invention relates to protection of a metal component exposed to a corroding medium. One or more of the following are provided: cathodic protection, measuring of a condition of the component, retarding or avoiding of fouling. A sacrificial anode is used as the energy source such that the electric circuit can provide a pulsating current, voltage, automatically adapted current, or protecting potential. Germanium solid state elements are used.

Abstract: An apparatus, system, method and computer program product directed to controlling corrosion, particularly space weather induced corrosion, of a conductive structure in contact with a corrosive environment and coated with a semiconductive coating, where the corrosion is controlled by a controllable filter and a corresponding electronic control unit configured to process and adjust the controllable filter in response to at least one measured parameter associated with space weather effects on the conductive structure.

Abstract: Environment-friendly process for descaling, pickling and finishing/passivating in a continuous, integrated and flexible manner, applicable to any type of stainless steel, regardless of its physical structure, chemical composition and nature of surface oxides to be removed, within a single plant in which the required chemical, electrochemical, mechanical and hydromechanical treatments are carried out, merely diversifying the operative conditions of each treatment according to the stainless steel type to be processed. The process and the plant according to the invention allow elevated reaction rate, excellent surface quality, low energy and chemical reagent consumption and total environmental compatibility. The figure shows the block diagram of an embodiment of the plant according to the invention.

Abstract: In a method of reducing corrosion of a metal material, a substance such as semiconductor for generating an electric current by thermal excitation is coated or adhered on a metal material surface, to be exposed to a water having a high temperature of 150° C. or more, of a boiler and ducts or pipes, to which hot water heated by the boiler contacts, of a thermal electric power plant or a nuclear reactor structural material or ducts or pipes surrounding the reactor in a nuclear power plant.

Abstract: A cathodic protection polymeric compound is disclosed. The compound has flowable material to serve as a binder, carbonaceous conductive media dispersed in the flowable material, sacrificial metal particles also dispersed in the flowable material. The carbonaceous conductive media serve as a carbon-based electron transfer agent and are in the form of particles, platelets, fibers, tubes, or combinations thereof. A galvanic circuit is formed by the metal particles serving as anodes, a metal substrate to be protected serving as the cathode, and the conductive media serving as the electron transfer agent. The flowable material can also include an ionically conductive or an inherently conductive polymer to further enhance the galvanic circuit.

Abstract: The present invention provides a curable cathodic corrosion protection powder coating, which comprises a thermosetting resin, a zinc borate compound, a curing agent in an amount effective to cure the coating. Further, the present invention also provides a method of cathode corrosion protection which includes the steps of subjecting the substrate to a mechanical treatment, applying to said treated steel surface, the cathodic protective coating, and polarizing the coated material as a cathode.

Abstract: An apparatus, system, method and computer program product directed to controlling corrosion of a conductive structure in contact with a corrosive environment and electrically connected to one or more anodes, wherein the anodes are less noble than the conductive structure, where the corrosion is controlled by a controllable filter and a corresponding electronic control unit configured to process at least one stored or measured parameter, and wherein the apparatus, system and method serve to prolong the lifetime of the one or more anodes by reducing, minimizing or substantially eliminating their sacrificial character.

Abstract: A method for protecting metal-containing structures, in particular electrically conductive structures, deposited on a substrate, against corrosive attacks, in particular electrocorrosion attacks. The method applies at least temporarily to the structure a passivation electric voltage in the passivation range of the conductive material concerned.

Abstract: A method and apparatus wherein an electrically conductive element is placed inside a previously installed metallic water vessel such as a supply pipe or well. A direct current voltage is then applied between the element and the conductive wall of the vessel. The conductive element can be a partially insulated wire. For causing deposition on the vessel, the voltage applied to the conductive element is of an amount sufficient to cause the potential of the metallic vessel to be lowered below the potential of the element by at least ?0.3 volts, and more adequately ?1.3 volts. An alternative embodiment involves reversing the polarity of the voltage applied between the conductive element and the vessel, causing the oxidation/reduction reaction to reverse, resulting in calcium carbonate being removed from the vessel by the production of acid at the surface of the vessel.

Abstract: The present invention provides a method of testing a cryogenic metal tank before it is put into service, in which said method said tank (1) is filled with water and appropriate measurements are performed where necessary, the method being characterized in that the following steps are performed: filling said metal cryogenic tank (1) with sea water; and providing the bottom and side metal walls (2, 3) of said tank (1) that are constituted essentially by bare steel, with temporary cathodic protection by injecting an electric current into anodes disposed within said tank (1) once said anodes become immersed. Advantageously, a first anode array (51) is placed in the immediate vicinity of the bottom of the tank using support means (52), said support means (52) and said first anode(s) (51) preferably being removable.

Abstract: A process of reducing scaling of a metal surface exposed to an aqueous solution from which scale may form after a period of exposure. The process comprises applying a cathodic potential to the surface for at least some of the period of exposure. In some cases, e.g. when an article is made of a ferrous metal, it is advantageous to coat the article with a different metal (e.g. copper or an alloy of copper) before applying the cathodic potential to avoid hydrogen generation and excessive current flow. An article to be protected from scaling may also advantageously be electrically isolated from other parts of an apparatus.

Abstract: An apparatus, system, method and computer program product directed to controlling corrosion of a conductive structure in contact with a corrosive environment and coated with a semiconductive coating, where the corrosion is controlled by a controllable filter and a corresponding electronic control unit configured to process at least one stored or measured parameter.

Abstract: The present invention pertains to: a method of ultrasonic pickling by impressing a protective potential of not less than −300 mV baser than the corrosion potential of an ultrasonic diaphragm installed in a pickling solution on the ultrasonic wave imposing means and carrying out pickling while supplying corrosion preventive current of not less than 100 mA/m2 to a corrosion preventive current imposing means whose negative electric terminal is connected to the ultrasonic wave imposing means and whose positive electric terminal is connected to the pickling solution or a travelling strip material; and an apparatus for ultrasonic pickling, as an apparatus to embody the method.

Abstract: This invention relates to a process for the derusting or removal of corrosion products form ferrous metal substrates by electrochemical treatment.

Abstract: A system for preventing corrosion of a surface of a metal structure in contact with a corrosive environment comprising:

Abstract: A method of protecting metals from corrosion by applying an alternating voltage to them, thereby reversing the metal's polarity with respect to its surroundings. Particular applications are for metals which are buried in soil or are exposed to an electrolyte. Amphoteric metals Steels, which are subject to hydrogen embrittlement when made cathodic, are also protected by polarity reversal.

Abstract: A heat exchanger and process for use with a corrosive fluid, such as sulphuric acid, having an anodic protection system for protecting the acid-contacted surfaces wherein the anodic protection system has a plurality of elongated cathodes of such cross sectional area and length as to operably maintain voltage losses due to current flow along the cathodes at values less than the allowable passive voltage ranges at the acid-contacted surfaces.