Radiation detectors and methods of using the radiation detectors that provide a route for surface decontamination during use are described. The detectors utilize light illumination of an internal surface during use. Light is in the longer UV-to-near-infrared spectra and desorbs contamination from internal surfaces of radiation detectors. The methods can be carried out while the detectors are in operation, preventing the appearance of the negative effects of radioactive and non-radioactive contamination during a detection regime and following a detection regime.

Plasma reactors and methods are provided for reducing the volume of radioactive nuclear wastes or toxic wastes where the surface contamination is the main source of radioactivity or toxicity. The radioactive or toxic wastes are prepared in the form of small particles and fed into a pulsed plasma reactor operating in fluidized bed configuration. The repetitively pulsed radio-frequency (rf) powered plasma reactor generates high power plasma for pulse duration between 10 s-10 ms. During the pulse, the plasma deliver a short burst of intense heat flux to the surface of waste feed particles. Due to the short pulse duration, the heat flux is concentrated on the surface without propagating much to the core of the particles. The localized heat flux preferentially removes the surface contaminants via vaporization. The removed waste in the vapor phase will be transferred out of the reactor where it may undergo additional treatments or disposed accordingly in a reduced volume. The residual particles which are free from surface contaminants can then be recycled or disposed as non-toxic or non-radioactive waste. By controlling the treatment time inside the plasma reactor along with the pulse power, duration and repetition rate, and the plasma chemical composition, the thickness of removed surface layers can be controlled to provide the efficient surface decontamination.

A method of decontaminating naturally occurring radioactive material (NORM) from downhole equipment may include injecting a NORM dissolver into an isolated region of a wellbore in which NORM-contaminated production equipment is located; and removing the NORM contaminants from the production equipment. The method may also include recommencing production of hydrocarbons following the decontamination.

Radiation detectors and methods of using the radiation detectors that provide a route for surface decontamination during use are described. The detectors utilize light illumination of an internal surface during use. Light is in the longer UV to near-infrared spectra and desorbs contamination from internal surfaces of radiation detectors. The methods can be carried out while the detectors are in operation, preventing the appearance of the negative effects of radioactive and non-radioactive contamination during a detection regime and following a detection regime.

The invention relates to an apparatus which comprises a pyrolytic plasma reactor (1) with: a conical head (8), on which are mounted: inlets (2, 3, 4); a first plasma torch (6); and first gas outlet (5); a cylindrical reaction chamber (9), under the head (8), and which comprises: a side wall (11) with a refractory covering (12); and a bottom (16), o with a decreasing cross-section, for receiving lavas; a base (10), for supporting the head (8) and the reaction chamber (9); and discharge means in the reaction chamber (9) and/or in the base (10) for discharging the lavas. By keeping the first torch (6) lit, the method comprises directing solid, liquid and gaseous hazardous waste towards the central portion of the plasma jet from the first torch (6), with no contact between the various types of hazardous waste. The dissociation conditions are improved by the invention.

Mobile apparatuses move within contaminated fluid to create fluid flows against structures that remove and prevent contaminant deposition on structure surfaces immersed in the fluid. Unsettling flows in water may exceed approximately 2 m/s for radionuclide particles and solutes found in nuclear power plants. Mobile apparatuses include pressurized liquid from a pump or pressurized source that can be chemically and thermally treated to maximize deposition removal. When spraying the pressurized liquid to create the deposition-removing flow, mobile apparatuses may be self-propelled within the fluid about an entire surface to be cleaned. Mobile apparatuses include filters keyed to remove the contaminants moved into the coolant by the flow, and by taking in ambient fluid, enable such filtering of the ambient fluid along with a larger flow volume and propulsion. Propulsion and the pressurized liquid in turn enhance intake of ambient fluid.

A method for producing an aqueous foam comprising (a) preparing a solution comprising at least one surfactant and at least one protic polar solvent, (b) bringing the solution into contact with a pressurised gas to obtain a two-phase mixture, and (c) injecting the two-phase mixture to obtain the aqueous foam after expansion or dispersion of the gas. The solution further comprises at least one gelling compound chosen from a non-nitrogenous polysaccharide and gelatin. An aqueous foam obtained by such method and uses of the same, in particular in the fields of decontamination, the purification of effluents, or the defusing or containment of explosive devices or suspected explosive devices.

A method for producing an aqueous foam comprising (a) preparing a solution comprising at least one surfactant and at least one protic polar solvent, (b) bringing the solution into contact with a pressurised gas to obtain a two-phase mixture, and (c) injecting the two-phase mixture to obtain the aqueous foam after expansion or dispersion of the gas. The solution further comprises at least one gelling compound chosen from a non-nitrogenous polysaccharide and gelatin. An aqueous foam obtained by such method and uses of the same, in particular in the fields of decontamination, the purification of effluents, or the defusing or containment of explosive devices or suspected explosive devices.

A decontamination method that includes the steps of decontaminating an object containing radioactive contaminated metals or alloys with a chemical decontamination agent including sulfuric acid (H.sub.2SO.sub.4) and forming a Ba or Sr precipitate by adding a Ba or Sr cation and a hydroxylion or halogen anion salts to the decontamination waste water.

The invention relates to means for protecting the environment from the consequences of fires complicated by a radiation factor. A composition for dust suppression and containment of radioactive products of combustion after a fire with a radiation factor has been extinguished comprises, as a surfactant, a mixture of an anionic, a non-ionic and an amphoteric surfactant, and has the following ratio of components: 3.0-7.0% by weight of an aqueous solution of polyvinyl alcohol (in terms of a mass fraction of dry product); 0.1-0.3% by weight of plasticizer; 11.0-29.0% by weight of surfactant; with water making up the remainder. The invention makes it possible to carry out dust suppression and containment of radioactive products of combustion which are formed on surfaces, including at elevated temperatures, after a fire has been extinguished.