In one embodiment, an alkylphenol copolymer is disclosed wherein the copolymer comprises at least one alkylphenol monomer and the alkylphenol copolymer exhibits the following: an oscillation displacement Θ of greater than 0 at a temperature of −5° C. in a first oscillation temperature sweep and an oscillation displacement Θ in a second oscillation temperature sweep within 25% of the oscillation displacement Θ in the first oscillation temperature sweep at a temperature of −5° C. In a further embodiment, a petroleum composition is disclosed wherein the composition comprises a petroleum source and a macromolecular compound wherein the macromolecular compound exhibits the following: an oscillation displacement Θ of greater than 0 at a temperature of −10° C. in a first oscillation temperature sweep, and an oscillation displacement Θ in a second oscillation temperature sweep within 25% of the oscillation displacement Θ in the first oscillation temperature sweep at a temperature of −10° C.

In one embodiment, an alkylphenol copolymer is disclosed wherein the copolymer comprises at least one alkylphenol monomer and the alkylphenol copolymer exhibits the following: an oscillation displacement Θ of greater than 0 at a temperature of −5° C. in a first oscillation temperature sweep and an oscillation displacement Θ in a second oscillation temperature sweep within 25% of the oscillation displacement Θ in the first oscillation temperature sweep at a temperature of −5° C. In a further embodiment, a petroleum composition is disclosed wherein the composition comprises a petroleum source and a macromolecular compound wherein the macromolecular compound exhibits the following: an oscillation displacement Θ of greater than 0 at a temperature of −10° C. in a first oscillation temperature sweep, and an oscillation displacement Θ in a second oscillation temperature sweep within 25% of the oscillation displacement Θ in the first oscillation temperature sweep at a temperature of −10° C.

A cleaning agent comprising a polyacrylate terpolymer and a maleic olefin compound may be added to an aqueous system having a metal surface, such as a metal surface of a heat exchanger, in a concentration sufficient to remove fouling deposits from the metal surface in neutral or alkaline conditions. The removal of fouling deposits with the application of the cleaning agent may occur while the system is shut down or in service.

A cleaning agent comprising a polyacrylate terpolymer and a maleic olefin compound may be added to an aqueous system having a metal surface, such as a metal surface of a heat exchanger, in a concentration sufficient to remove fouling deposits from the metal surface in neutral or alkaline conditions. The removal of fouling deposits with the application of the cleaning agent may occur while the system is shut down or in service.

Described herein are systems and methods for evaluating and mitigating the wax risks of a given hydrocarbon composition such as crude oil. The disclosed systems and methods enable rapid and ready prediction of wax risks using algorithms based on a small sample of the hydrocarbon composition. The wax risks are predicted using predictive models developed from machine learning. The disclosed systems and methods include mitigation strategies for wax risks that can include chemical additives, operation changes, and/or hydrocarbon blend.

Described herein are systems and methods for evaluating and mitigating the wax risks of a given hydrocarbon composition such as crude oil. The disclosed systems and methods enable rapid and ready prediction of wax risks using algorithms based on a small sample of the hydrocarbon composition. The wax risks are predicted using predictive models developed from machine learning. The disclosed systems and methods include mitigation strategies for wax risks that can include chemical additives, operation changes, and/or hydrocarbon blend.

The furnace of a delayed coking unit which is utilized for heating residue feeds to high temperatures can suffer from decrease in run length and fouling caused by caustic carryover from the upstream desalter unit. An antifoulant additive for preventing caustic induced fouling of thermal cracker furnace tubes is disclosed. The described antifoulant additive acts by converting the inorganic caustic compound such as NaOH to naphthenate salt of the metal as well as by reducing the fouling tendency of the whole feedstock, thereby making it ineffective in causing coking reaction. The additive finds application in thermal residue upgradation furnaces such as delayed coking unit, visbreaker, etc.

The furnace of a delayed coking unit which is utilized for heating residue feeds to high temperatures can suffer from decrease in run length and fouling caused by caustic carryover from the upstream desalter unit. An antifoulant additive for preventing caustic induced fouling of thermal cracker furnace tubes is disclosed. The described antifoulant additive acts by converting the inorganic caustic compound such as NaOH to naphthenate salt of the metal as well as by reducing the fouling tendency of the whole feedstock, thereby making it ineffective in causing coking reaction. The additive finds application in thermal residue upgradation furnaces such as delayed coking unit, visbreaker, etc.

A method for reducing or preventing corrosion or fouling in an apparatus for carrying out a chemical process, where corrosion or fouling is caused by acidic compounds present in the chemical process, which comprises the addition of at least one quaternary ammonium hydroxide of the formula (I) to the apparatus, wherein the chemical process is carried out: [Chem. 1] where R.sup.1, R.sup.2, R.sup.3 are each independently C.sub.1-C.sub.10 alkyl; R.sup.4 is inter alia C.sub.1-C.sub.18 alkyl, benzyl, monocycloalkyl having 5, 6, 7 or 8 carbon atoms, bicycloalkyl having 6 to 8 carbon atoms, tricycloalkyl having 7 to 10 carbon atoms, where monocycloalkyl, bicycloalkyl and tricycloalkyl are unsubstituted or substituted by 1 or 2 methyl groups, or tri-C.sub.1-C.sub.4 alkyl ammonium groups. R.sup.1 and R.sup.2 together with the nitrogen atom may also form a 5 or 6-membered, saturated nitrogen heterocycle, which is unsubstituted or carries 1 or 2 methyl groups; and/or R.sup.3 and R.sup.4 together with the nitrogen atom may also form a 5 or 6-membered, saturated nitrogen heterocycle, which is unsubstituted or carries 1 or 2 methyl groups.

The present disclosure relates to methods and compositions for reducing fouling by natural and synthetic foulants that tend to precipitate during hydrocarbon collecting, processing, transporting, and storing. The method includes applying a composition to a hydrocarbon containing the foulant. The composition includes an effective amount of a reaction product of an α-olefin/maleic anhydride copolymer and an amino-hydroxy compound. The foulants may include wax and asphaltenes, for example.