This invention relates to compositions and methods for the at least partial dissolution, disruption and/or removal of deposit, such as scale and other deposit, from heat exchanger components. The heat exchanger components can include pressurized water reactor steam generators. In accordance with the invention, elemental metal is added locally to the surface of the deposit and/or anodic or cathodic current is applied locally to the deposit surface to destabilize or weaken the deposit. Subsequently, mechanical stress is applied to the weakened deposit to disrupt and remove the deposit from the surface of the heat exchanger component.

This invention relates to compositions and methods for the at least partial dissolution, disruption and/or removal of deposit, such as scale and other deposit, from heat exchanger components. The heat exchanger components can include pressurized water reactor steam generators. In accordance with the invention, elemental metal is added locally to the surface of the deposit and/or anodic or cathodic current is applied locally to the deposit surface to destabilize or weaken the deposit. Subsequently, mechanical stress is applied to the weakened deposit to disrupt and remove the deposit from the surface of the heat exchanger component.

A method of suspending elemental sulfur in water includes the steps of providing water including elemental sulfur and hydrogen sulfide and adding from about 1 to about 100 parts by weight of a sulfur suspension additive to the water based on one million parts by weight of the water to suspend the elemental sulfur in the water. The sulfur suspension additive is chosen from an alkyldiphenyloxide disulfonate or salt thereof, a secondary alcohol ethoxylate, a non-ionic ethylene oxide and/or propylene oxide copolymer, and combinations thereof.

Processes for inhibiting scale produced during wet process phosphoric acid production by adding a scale-inhibiting amount of a reagent having a primary amine-containing polymer to at least one stage of a wet process phosphoric acid production process are provided herein, wherein said primary amine-containing polymer includes one or more organic moieties that reduce the polymer's solubility in an aqueous environment as compared to its native form, thereby reducing or preventing scale in the wet process phosphoric acid production process.

Processes for inhibiting scale produced during wet process phosphoric acid production by adding a scale-inhibiting amount of a reagent having a primary amine-containing polymer to at least one stage of a wet process phosphoric acid production process are provided herein, wherein said primary amine-containing polymer includes one or more organic moieties that reduce the polymer's solubility in an aqueous environment as compared to its native form, thereby reducing or preventing scale in the wet process phosphoric acid production process.

Methods for reducing aluminosilicate containing scale in an alumina recovery process involving treating an alumina recovery process equipment surface with a degradation-resistant scale inhibiting composition having high ionic strength prior to exposure to an alumina recovery process stream.

Methods for reducing aluminosilicate containing scale in an alumina recovery process involving treating an alumina recovery process equipment surface with a degradation-resistant scale inhibiting composition having high ionic strength prior to exposure to an alumina recovery process stream.

A synergistic composition comprising a THP salt and a biopenetrant, in which the biopenetrant comprises a polymer of an unsaturated carboxylic acid or a copolymer of an unsaturated carboxylic acid with a sulphonic acid, said polymer or copolymer being terminated by a mono- or diphosphonated unsaturated carboxylic acid group or having such monomers incorporated into the polymer backbone. This composition acts synergistically to enhance the biocidal efficacy of the THP salt against both planktonic (free-swimming) and sessile (attached) bacteria, and also acts synergistically to enhance the efficacy of the THP salt in the dissolution of iron sulphide scale.

A synergistic composition comprising a THP salt and a biopenetrant, in which the biopenetrant comprises a polymer of an unsaturated carboxylic acid or a copolymer of an unsaturated carboxylic acid with a sulphonic acid, said polymer or copolymer being terminated by a mono- or diphosphonated unsaturated carboxylic acid group or having such monomers incorporated into the polymer backbone. This composition acts synergistically to enhance the biocidal efficacy of the THP salt against both planktonic (free-swimming) and sessile (attached) bacteria, and also acts synergistically to enhance the efficacy of the THP salt in the dissolution of iron sulphide scale.

A method for selecting chemical agents for removing scale, the chemical agents being adapted for scale and its base material. A method for selecting chemical agents for removing scale, the method including steps of: obtaining coordinates A of an intrinsic physical property value based on a Hansen solubility parameter of an entire scale of interest; obtaining coordinates B of an intrinsic physical property value based on a Hansen solubility parameter of a surface on a base material side of the scale of interest; obtaining coordinates C of an intrinsic physical property value based on a Hansen solubility parameter of a base material of interest; selecting a penetrant having coordinates D of an intrinsic physical property value based on a Hansen solubility parameter based on an interaction radius Ra of the scale of interest with the coordinates A at the center; selecting a remover having coordinates E of an intrinsic physical property value based on a Hansen solubility parameter based on a positional relationship between the coordinates B and the coordinates C; and selecting an inducer having coordinates F of an intrinsic physical property value based on a Hansen solubility parameter based on a positional relationship between the coordinates D and the coordinates E.