Dispersions of coal ash in water can be inhibited or prevented from scaling and simultaneously be inhibited or prevented from fouling by introducing thereto an additive blend that includes an anionic water-soluble polymer and a second polymer different from the anionic water-soluble polymer, where the second polymer is selected from the group consisting of copolymers and terpolymers having a plurality of hydrophobic groups.

A composition for corrosion control in aqueous systems, the composition providing a formulation of a concentrated aluminum corrosion inhibitor; and (i) a polycarboxylic acid polymer, (ii) a sulfonic acid polymer, (iii) a combination of a polycarboxylic acid and a polysulfonic acid, (iv) an organic phosphonate, (v) a combination of a phosphonate and a polycarboxylic acid, or (vi) a combination of a phosphonate and a polysulfonic acid. A method for corrosion control in aqueous systems, the method providing a concentrated formulation, the concentrated formulation having an aluminum corrosion inhibitor and (i) a polycarboxylic acid polymer, (ii) a sulfonic acid polymer, (iii) a combination of a polycarboxylic acid and a polysulfonic acid, (iv) an organic phosphonate, (v) a combination of a phosphonate and a polycarboxylic acid, or (vi) a combination of a phosphonate and a polysulfonic acid; and delivering the concentrated formulation to an aqueous stream.

An additive comprising one or more C.sub.3-C.sub.12 hydroxycarboxylic acids and/or one or more C.sub.3-C.sub.12 hydroxycarboxylic acid salts may be added to an aqueous system having galvanized metallurgy or a carbon steel surface in an effective amount to passivate a galvanized coating on the metallurgy or to decrease white rust formation or other types of corrosion upon the galvanized metallurgy or carbon steel surface in an aqueous system. In a non-limiting embodiment, the C.sub.3-C.sub.12 hydroxycarboxylic acid or the C.sub.3-C.sub.12 hydroxycarboxylic acid salt additive may utilize the zinc in the galvanized coating to achieve passivation. The passivation may occur while the system is shut down or in service. The aqueous system may be or include a cooling tower, a cooling water system, and combinations thereof. The additive may be used with or in the absence of a phosphorous-containing compound.

A system and method of controlling the treatment of water systems comprises multiple feeders for separately feeding treatment products, in the form of concentrated, non-hazardous, liquids with a single active ingredient, to a water system to treat various issues, such as corrosion and biofilms. A sensor verifies delivery of the treatment product to the water system. A controller controls activation of each feeder to control a feed rate according to programmed functions. The controller receives signals from sensors, which can be used as inputs in calculating feed rates or feeder activation times according to the programed functions and can alter treatment product feed rates based on real time data regarding water system chemistry or flow rates. The controller can send and receive data, signals, alerts, alarms or changes in programming to or from remote users, remote computers, or a water system controller.

A terpolymerized corrosion and scale inhibitor used in circulating cooling water of central air conditioning, containing tourmaline, polyaspartic acid, polyepoxysuccinic acid, polymaleic acid, etidronic acid, zinc salt, and the like, wherein the content of the tourmaline is 5-500 g/t (calculated based on solid form); the content of polyaspartic acid, polyepoxysuccinic acid, polymaleic acid and etidronic acid is 2-60 g/t (calculated based on liquid form); and the content of the zinc salt is 0.2-0.8 g/t (calculated based on solid form), is provided. Also disclosed is a method of preparing the terpolymerized corrosion and scale inhibitor used in circulating cooling water of central air conditioning.

Methods for treating a water system to prevent scaling. The water system includes water that is prone to scaling and that is processed to remove an organic contaminant with a GAC system and/or an IX system. Antiscalant compositions can be selected to reduce the amount of antiscalant that is adsorbed or otherwise removed in the contaminant removal system so that a sufficient amount of antiscalant composition remains in the water stream.

Disclosed herein are extended- and multimodal-release compositions for inhibiting scale in an industrial water system. In an example, an extended-release composition for inhibiting scale in an industrial water system includes a solid, particulate scale inhibitor. The solid, particular scale inhibitor may include a phosphonate, a carboxylate, or a combination thereof; and a divalent cation, a trivalent cation, or a combination thereof. In some cases, the solid, particulate scale inhibitor is substantially free of an inert material

A composition for corrosion control in aqueous systems, the composition providing a formulation of a concentrated aluminum corrosion inhibitor; and (i) a polycarboxylic acid polymer, (ii) a sulfonic acid polymer, (iii) a combination of a polycarboxylic acid and a polysulfonic acid, (iv) an organic phosphonate, (v) a combination of a phosphonate and a polycarboxylic acid, or (vi) a combination of a phosphonate and a polysulfonic acid. A method for corrosion control in aqueous systems, the method providing a concentrated formulation, the concentrated formulation having an aluminum corrosion inhibitor and (i) a polycarboxylic acid polymer, (ii) a sulfonic acid polymer, (iii) a combination of a polycarboxylic acid and a polysulfonic acid, (iv) an organic phosphonate, (v) a combination of a phosphonate and a polycarboxylic acid, or (vi) a combination of a phosphonate and a polysulfonic acid; and delivering the concentrated formulation to an aqueous stream.