Abstract: A method for monitoring and reducing corrosion in furnace boiler tubes measures electrochemical noise associated with corrosion mechanisms while corrosion is occurring at the surface of the tubes as they are exposed to combustion products. This noise is detected using a probe at the boiler waterwall surface that is connected to a corrosion monitor. The monitor contains a computer and software which determines a corrosion rate from the measured electrochemical noise. That rate is compared to a standard to determine if the rate is within acceptable limits. If not, the operator of the furnace or an Adaptive Process Controller (APC) is notified and adjusts one or more burners to change the combustion products that are responsible for the corrosion. Such an adjustment could be made by changing the amount of air or fuel being provided to the burner or other air slots or air ports.

Abstract: A method for delivering encapsulated materials to a subsurface environment, for the treatment of the subsurface environment, has the steps of: (a) loading the lumen of hollow microtubules with an active agent selected for treating the subsurface environment, where the hollow microtubules are compatible with the subsurface environment; and (b) administering the hollow microtubules to the subsurface environment, permitting the controlled release of the active agent into the subsurface environment. This method may be practiced using a slurry of hollow microtubules, where the lumen of these microtubules is loaded with an agent for the treatment of petroleum well environments, and where these loaded microtubules are dispersed in a liquid phase carrier selected from aqueous carriers, non-aqueous carriers, and emulsions of aqueous and non-aqueous materials. This method may also be practiced using a pill made of a consolidated mass of tubules loaded with one or more active agents, typically bound with a binder.

Abstract: A subsea raw water injector including a pump which is connected to an injection string and a filter connected to an inlet of the pump to remove particulates from the surrounding sea water. The filter is in the form of an inclined tube settler disposed such that particulates separated from sea water flowing through it are discharged to the seabed.

Abstract: A method and apparatus is presented for analyzing directly obtained electrochemical noise measurements at cellular surfaces to assess cellular behavior and metabolic activity. The apparatus comprises a container (1) into which culture medium containing the cells to be assessed (2) has been introduced. Located within the container and partially submerged by the culture medium is a main electrode (3) which is a chemically inert electrically conductive surface such as gold film. This electrically conductive surface supports the adherent, viable cells to be assessed, and which may have been previously grown on the electrode to near confluence. The container is closed by a lid (4) which is penetrated by a tube (5) filled with an electrochemically conducting medium that is in electrochemical contact with a reference electrode. The end of the tube (5) is immersed in the culture medium.

Abstract: A method for producing electrochemical impedance spectra. Spontaneously occuring coupling current noise between an array of electrodes which may be of substantially the same material is detected. A time domain record of the detected current noise is stored and the time domain record of the detected current noise is transformed to the frequency domain. Spontaneously occurring potential noise between the array of electrodes and a further electrode is detected. A time domain record of the detected potential noise is stored and the time domain record of the detected potential noise is transformed to the frequency domain. The frequency domain current noise and potential noise transformations are then transformed to the impedance domain to produce the required electrochemical impedance spectra.

Abstract: Stress-corrosion damage is monitored in penetrations traversing the wall of a vessel containing an electrolyte, such as a nuclear reactor pressure vessel containing a coolant. The vessel wall has tubular penetrations for coupling external devices to internal structures of the vessel while maintaining a pressure barrier, such as control rod guides and sensor signal cables. The penetrations are subject to stress-corrosion damage, especially adjacent welds affixing the tubes to the vessel head. One or more of the penetrations is provided with a probe forming with the tube an electrochemical sensor cell, including an electrode exposed to the electrolyte together with the surface of the penetration. The electrode and the surface are otherwise insulated, and a plurality of electrodes can be arrayed for monitoring distinct localized areas.

Abstract: A method and apparatus for detecting and measuring localized corrosion of a metallic surface is described. An array of electrodes fabricated from the same material as the metallic surface is exposed to the same corrosion conditions as the metallic surface. The coupling current between two electrodes of the array is measured, and the electrochemical current noise originating in the electrode array is measured. The two measurements are compared, the electrochemical current noise increasing as compared to the coupling current as the degree to which corrosion is localized increases. The electrochemical current noise originating in the coupled array electrode and the associated electrochemical corrosion potential noise are produced by the natural corrosion processes.