An offshore water production facility to be located on a body of water includes a floating object, at least one wind turbine, a power generator that is coupled to the wind turbine and a water production system. The floating object includes a plurality of buoyancy assemblies that support at least one column on which a wind turbine is mounted. On the at least one column further a process equipment deck is mounted below an operating area of the wind turbine and above a water surface level. The water production system is arranged on the process equipment deck, and the water production system is configured for subsea well water-injection and includes an ultra-filtration unit and a membrane de-aeration unit for water to be injected.

Water containing selenium, for example flue gas desulfurization (FGD) blowdown water is treated with a combination of biological and chemical treatment and membrane filtration. The biologically treated water is dosed with a dithiocarbamate compound and flocculated prior to membrane filtration. Optionally, the treatment may be enhanced with one or more adsorptive agents prior to, or in conjunction with, membrane filtration. Membrane concentrate may be re-circulated to one or more biological treatment zones. The biological treatment may be by way of suspended growth, fixed growth on a moving bed, or both. One or more biological treatment zones may be controlled considering their oxygen reduction potential (ORP). Optionally, the biological treatment includes an aerobic zone following one or more anoxic or anaerobic zones. The non-aerobic zones remove selenium and optionally nitrogen and sulfur. The aerobic zone removes carbon, which may include carbon added as a nutrient in a non-aerobic zone.

Water containing selenium, for example flue gas desulfurization (FGD) blowdown water is treated with a combination of biological and chemical treatment and membrane filtration. The biologically treated water is dosed with a dithiocarbamate compound and flocculated prior to membrane filtration. Optionally, the treatment may be enhanced with one or more adsorptive agents prior to, or in conjunction with, membrane filtration. Membrane concentrate may be re-circulated to one or more biological treatment zones. The biological treatment may be by way of suspended growth, fixed growth on a moving bed, or both. One or more biological treatment zones may be controlled considering their oxygen reduction potential (ORP). Optionally, the biological treatment includes an aerobic zone following one or more anoxic or anaerobic zones. The non-aerobic zones remove selenium and optionally nitrogen and sulfur. The aerobic zone removes carbon, which may include carbon added as a nutrient in a non-aerobic zone.

A desulfurization system has an oxidation process unit, and a multi-stage, liquid-liquid extraction unit in series with the oxidation process unit. The multi-stage, liquid-liquid extraction unit spits a fuel input from the oxidation process unit into a desulfurized fuel that is output for use, and a by-product. A solvent/sulfur/hydrocarbon separation process unit receives the by-product from the multi-stage, liquid-liquid extraction unit.

A desulfurization system has an oxidation process unit, and a multi-stage, liquid-liquid extraction unit in series with the oxidation process unit. The multi-stage, liquid-liquid extraction unit spits a fuel input from the oxidation process unit into a desulfurized fuel that is output for use, and a by-product. A solvent/sulfur/hydrocarbon separation process unit receives the by-product from the multi-stage, liquid-liquid extraction unit.

A calcium and/or magnesium additive for membrane fouling control made up of particles for forming a dynamic protective layer on the membrane for fouling control of the membrane, when added in the liquid flowing through the membrane, wherein the particles are synthetic mineral precipitate particles based on calcium and/or magnesium selected from the group consisting of ultrafine synthetic mineral precipitate particles and microfine synthetic mineral precipitate particles, as well as a process and system for membrane fouling control.

A calcium and/or magnesium additive for membrane fouling control made up of particles for forming a dynamic protective layer on the membrane for fouling control of the membrane, when added in the liquid flowing through the membrane, wherein the particles are synthetic mineral precipitate particles based on calcium and/or magnesium selected from the group consisting of ultrafine synthetic mineral precipitate particles and microfine synthetic mineral precipitate particles, as well as a process and system for membrane fouling control.

In an embodiment is provided a process to re-refine used oil that includes introducing a used oil and a solvent to a separation unit under separation conditions selected to produce a purified oil product, the separation unit comprising a porous membrane, a semiporous membrane, or both; and separating the used oil to obtain an effluent comprising a purified oil product. In another embodiment is provided an apparatus for re-refining used oil that includes a separation unit comprising a porous or semiporous membrane; a used oil feed coupled to an inlet of the separation unit; and an inlet of a diffusate collection unit coupled to an outlet of the separation unit. In another embodiment is provided a composition generated from a membrane separation process that includes a base oil, the composition having a soot content of about 0.05% or less.

A system for membrane fouling control configured to run one or more filter cycles, wherein each filter cycle of the one or more filter cycles includes an operation mode and a cleaning mode. The system includes: a first conduct portion; a second conduct portion; a membrane arranged between the first conduct portion and the second conduct portion. The membrane is configured in the operation mode to filter a liquid to be filtered by conducting it from the first conduct portion to the second conduct portion. A fouling control means filled with fouling control particles is added in the operation mode in the first conduct portion so that a dynamic protective layer is formed on the membrane. The fouling control particles are mineral particles based on calcium and/or magnesium.

A system for membrane fouling control configured to run one or more filter cycles, wherein each filter cycle of the one or more filter cycles includes an operation mode and a cleaning mode. The system includes: a first conduct portion; a second conduct portion; a membrane arranged between the first conduct portion and the second conduct portion. The membrane is configured in the operation mode to filter a liquid to be filtered by conducting it from the first conduct portion to the second conduct portion. A fouling control means filled with fouling control particles is added in the operation mode in the first conduct portion so that a dynamic protective layer is formed on the membrane. The fouling control particles are mineral particles based on calcium and/or magnesium.