The invention relates to cleaning deposits of various natures from metal, glass and ceramic surfaces of industrial equipment and can be used for the removal of such deposits, as metal oxides (iron, chromium, nickel, etc.), carbonate and salt deposits, asphalt-tar-paraffin deposits and deposits of an oily nature, deposits of organic and biological nature (bacterial deposits). The proposed solution for removing deposits of different natures comprises hydrogen peroxide, complexing agent, calixarene and water in the following quantitative ratio, wt. %: hydrogen peroxide, 2-90; complexing agent, 3-30; calixarene, 0.01-10; water, the balance. EFFECT: increased degree of cleaning off deposits of various natures with simultaneous reduction of solution aggressiveness to structural materials.

A substrate processing apparatus includes a substrate holder configured to horizontally hold and rotate a substrate which has a recess and a base metal layer exposed from a bottom surface of the recess; and a pre-cleaning liquid supply configured to supply a pre-cleaning liquid such as dicarboxylic acid or tricarboxylic acid onto the substrate being held and rotated by the substrate holder, to thereby pre-clean the base metal layer. A temperature of the pre-cleaning liquid on the substrate is equal to or higher than 40 C.

A substrate processing apparatus includes a substrate holder configured to horizontally hold and rotate a substrate which has a recess and a base metal layer exposed from a bottom surface of the recess; and a pre-cleaning liquid supply configured to supply a pre-cleaning liquid such as dicarboxylic acid or tricarboxylic acid onto the substrate being held and rotated by the substrate holder, to thereby pre-clean the base metal layer. A temperature of the pre-cleaning liquid on the substrate is equal to or higher than 40 C.

Described herein is an aqueous composition for removing cryolitic deposits from plants or parts of plants which serve for the conversion treatment of metal surfaces, said composition including a) at least one mineral acid, and b) at least one dicarboxylic acid of the formula HOOC(CH.sub.2).sub.xCOOH,
where x is 0 to 3 and no borate-containing compounds have been added to the composition. Also described herein is a corresponding method for removing cryolitic deposits.

Described herein is an aqueous composition for removing cryolitic deposits from plants or parts of plants which serve for the conversion treatment of metal surfaces, said composition including a) at least one mineral acid, and b) at least one dicarboxylic acid of the formula HOOC(CH.sub.2).sub.xCOOH,
where x is 0 to 3 and no borate-containing compounds have been added to the composition. Also described herein is a corresponding method for removing cryolitic deposits.

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.

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 a method for pickling steel sheets 8, the steel sheets being continuously dipped in a pickling bath 1, containing a pickling solution 10, the bath being connected to a treatment unit including a recirculation tank 3, circulators 12 and 13, a continuous entering flow 11 of the solution being fed into an ultrafiltration device 2 from the recirculation tank 3 and two flows exiting the ultrafiltration device, one filtered exiting flow 21 being then fed back inside the recirculation tank 3 and one unfiltered flow 22, the treatment unit including no storage tank.

An aqueous synthetic acid composition for use in oil industry activities, said composition comprising: lysine and hydrogen chloride in a molar ratio ranging from 1:3 to 1:12.5, preferably from more than 1:5 to 1:8.5; it can also further comprise a metal iodide or iodate; an alcohol or derivative thereof Said composition demonstrates advantageous properties over known synthetic acids at temperatures above 90 C. Said composition is useful in various oil and gas industry operations. Preferred embodiments of said composition providing substantial advantages in matrix acidizing by increasing the effectiveness of wormholing compared to conventional mineral acids such as HC1.

An aqueous synthetic acid composition for use in oil industry activities, said composition comprising: lysine and hydrogen chloride in a molar ratio ranging from 1:3 to 1:12.5, preferably from more than 1:5 to 1:8.5; it can also further comprise a metal iodide or iodate; an alcohol or derivative thereof Said composition demonstrates advantageous properties over known synthetic acids at temperatures above 90 C. Said composition is useful in various oil and gas industry operations. Preferred embodiments of said composition providing substantial advantages in matrix acidizing by increasing the effectiveness of wormholing compared to conventional mineral acids such as HC1.