Provided herein are supercritical upgrading reactors and reactor systems for upgrading a petroleum-based composition by using one or more supercritical upgrading reactors and one or more supercritical standby reactors that alternate functions such that the supercritical upgrading reactor is converted to a supercritical standby reactor and the supercritical standby reactor is converted to a supercritical upgrading reactor. The supercritical upgrading reactor upgrades a combined feed stream while a supercritical standby reactor delivers a cleaning fluid into the supercritical standby reactor. The supercritical reactors may have one or more catalyst layers and one or more purging fluid inlets, and the catalyst layers may have differing void volume ratios.

Provided herein are supercritical upgrading reactors and reactor systems for upgrading a petroleum-based composition by using one or more supercritical upgrading reactors and one or more supercritical standby reactors that alternate functions such that the supercritical upgrading reactor is converted to a supercritical standby reactor and the supercritical standby reactor is converted to a supercritical upgrading reactor. The supercritical upgrading reactor upgrades a combined feed stream while a supercritical standby reactor delivers a cleaning fluid into the supercritical standby reactor. The supercritical reactors may have one or more catalyst layers and one or more purging fluid inlets, and the catalyst layers may have differing void volume ratios.

Antifoulant compositions and methods are used for inhibiting fouling on structural parts of a system exposed to a fluid hydrocarbon or petrochemical stream. Polyamine antifoulants are added to such systems. The polyamine antifoulants may be conjointly used with dispersants and/or fatty acids. The fatty acids have been found to reduce thermal degradation of the polyamine antifoulants.

Antifoulant compositions and methods are used for inhibiting fouling on structural parts of a system exposed to a fluid hydrocarbon or petrochemical stream. Polyamine antifoulants are added to such systems. The polyamine antifoulants may be conjointly used with dispersants and/or fatty acids. The fatty acids have been found to reduce thermal degradation of the polyamine antifoulants.

An anti-fouling composition has been developed that provides an advantageous reduction in the fouling of a structural part in a petroleum-refining system including inhibiting deposition of solids in equipment and lines used for crude oil production and processing. The anti-fouling compositions contain a phosphate ester and a polyalkylene ester.

Methods and compositions for inhibiting carbonyl-based fouling of basic wash systems. The methods comprise contacting the hydrocarbon stream that is or will be subjected to such washing with water soluble or water dispersible copolymers comprising repeat units of 1) ethylenically unsaturated monomers such as acrylic acid with one or more 2) other repeat units such as alkyl acrylates, allyl ethers, ethoxylated allyl repeat units, etc. In other embodiments, a third repeat unit 3) is present and may comprise a hydrophobic moiety such as a styrene repeat unit. The compositions may be terpolymers comprising repeat units 1), 2), and 3).

Methods and compositions for inhibiting carbonyl-based fouling of basic wash systems. The methods comprise contacting the hydrocarbon stream that is or will be subjected to such washing with water soluble or water dispersible copolymers comprising repeat units of 1) ethylenically unsaturated monomers such as acrylic acid with one or more 2) other repeat units such as alkyl acrylates, allyl ethers, ethoxylated allyl repeat units, etc. In other embodiments, a third repeat unit 3) is present and may comprise a hydrophobic moiety such as a styrene repeat unit. The compositions may be terpolymers comprising repeat units 1), 2), and 3).

Methods may include admixing an additive composition with a hydrocarbon fluid, wherein the additive composition contains at least one inhibitor and at least one sub-micron particle. Additional methods may include providing an additive composition containing at least one inhibitor and at least one sub-micron particle; adding the additive composition to a fluid capable of precipitating at least one of at least of asphaltenes, wax, scale, and gas hydrates; and transporting the fluid containing the additive composition.

Methods may include admixing an additive composition with a hydrocarbon fluid, wherein the additive composition contains at least one inhibitor and at least one sub-micron particle. Additional methods may include providing an additive composition containing at least one inhibitor and at least one sub-micron particle; adding the additive composition to a fluid capable of precipitating at least one of at least of asphaltenes, wax, scale, and gas hydrates; and transporting the fluid containing the additive composition.

A method includes receiving a water stream from a hydrocarbon production facility, the water stream having a first concentration of a kinetic hydrate inhibitor (KHI); flowing the water stream through a heat exchanger to heat the water stream to a target temperature; mixing the heated water stream with a treatment chemical to form a two-phase mixture, the treatment chemical having an affinity for the KHI; flowing the two-phase mixture into a separator; and physically separating the two-phase mixture into a first phase and a second phase, the first phase including water and having a second concentration of the KHI less than the first concentration, and the second phase including the KHI and the treatment chemical, the density of the second phase being less than the density of the first phase.