According to one or more embodiments, sulfate ions may be removed from seawater to form an injection fluid by a method including passing the seawater and formation water to a mixing tank. The seawater may comprise sulfate ions. The formation water may comprise barium ions. The seawater and formation water may be passed to the mixing tank in a ratio determined by a computerized geochemical model. The method may further include mixing the seawater and formation water to form a mixed fluid and passing the mixed fluid to a clarifier, where a barium sulfate precipitate may be formed and at least a portion of the barium sulfate precipitate may be separated from the mixed fluid. The method may further include passing the mixed fluid to a microfiltration system, where at least a portion of the barium sulfate precipitate may be removed from the mixed fluid to form an injection fluid.

An electrostatic coalescer apparatus for separating water from a crude oil emulsion comprises a vessel housing having a cavity, an inlet for receiving a crude oil emulsion and outlets for water and purified crude oil. First and second pairs of electrodes are positioned in the vessel cavity. A first Scott-T transformer circuit is coupled to the first pair of electrodes and a second Scott-T transformer circuit is coupled to the second pair of electrodes. The first and second Scott-T transformer circuit receive as an input a 3-phase power supply and output a 2-phase high voltage signal pairs of electrodes. The 2-phase voltage generated between the first pair of electrodes is of the same amplitude and phase as the voltage generated between the second pair of electrodes via the respective Scott-T transformer circuits. A method comprises steps performed during operation of the apparatus.

The present disclosure is directed to a separation system having a first inlet line through which a multiphase fluid is directed; a first separator connected to the first inlet line, the first separator being configured to separate the fluid into a heavy fraction primarily comprising solids and a light fraction primarily comprising gas, oil and water, the first separator comprising a heavy fraction outlet for discharge of the heavy fraction and a light fraction outlet for discharge of the light fraction; a heavy fraction outlet line connected to the heavy fraction outlet; a light fraction outlet line connected to the light fraction outlet; a second inlet line connected to the light fraction outlet line; a second separator connected to the second inlet line, the second separator being configured to separate the light fraction into separate gas, oil and water fractions, and the second separator comprising a gas outlet for discharge of the gas fraction, an oil outlet for discharge of the oil fraction, and a water outlet for discharge of the water fraction; a gas line connected to the gas outlet, an oil line connected to the oil outlet and a water line connected to the water outlet; a plurality of electrically operated valves for controlling fluid flow through respective ones of said lines; a plurality of sensors for measuring respective characteristics of the fluid; and a system controller configured to operate the valves based on inputs from the sensors to thereby control fluid flow through said lines.

The present invention relates to a method for removing hydrocarbons from produced water, comprising: (i) separating produced water from a hydrocarbon and water mixture extracted from a subterranean formation: (ii) contacting said produced water with multivalent metal cations to produce a mixture of produced water and multivalent metal cations; and (iii) removing hydrocarbons from said mixture in a hydrocyclone and/or a compact flotation unit to give treated produced water, wherein the concentration of hydrocarbons in said produced water is less than 10% wt.

Systems and methods for crude oil separations including degassing, dewatering, desalting, and stabilization. One method includes separating crude oil into a crude oil off-gas and a partially degassed crude oil output; compressing the crude oil off-gas; applying the compressed crude oil off-gas for indirect heating through reboilers of the partially degassed crude oil output; and directly mixing with the crude oil a compressed atmospheric pressure gas. In some embodiments, multiple reboilers are used. In some embodiments, heat exchangers are used. Aftercoolers are used after the compressor to cool the gas; knockout drums are used after the coolers to separate liquids.

A center tube and a central fluid supply tube combination includes a center tube body defining a longitudinal length, and a central reservoir. The center tube also includes an apertured annular wall extending axially the majority of the longitudinal length, and a first annular solid wall extending axially from the apertured annular wall. A central fluid supply tube is disposed in the central reservoir, and includes a second annular solid wall that is radially surrounded by the apertured annular wall of the center tube. The second annular solid wall defines a supply passage with a fully circular flow flux.

Systems and methods for controlling desalting and dehydration of crude oil, one method including monitoring total dissolved solids (TDS) content at an outlet stream from a crude oil separation unit, the outlet stream comprising water; monitoring basic sediment and water (BS&W) content at an outlet stream from the crude oil separation unit, the outlet stream comprising processed crude oil; determining pounds per thousand barrels (PTB) salt content and volumetric water content of a dried, desalted crude oil product stream using the TDS content and BS&W content; and controlling a process input to the method from a comparison between the PTB salt content and volumetric water content of the dried, desalted crude oil product stream versus a maximum set value for PTB salt content and volumetric water content of the dried, desalted crude oil product stream.

A diester-based compound is continuously prepared in a total of n reaction units serially connected, each reaction unit includes a reactor and layer separator. The preparation includes: supplying and esterifying a feed stream including a dicarboxylic acid and an alcohol into a first reactor to prepare a reaction product, and supplying a lower draw-off stream including the reaction product into reactors of rear reaction units; supplying an upper draw-off stream of the first reactor into a first layer separator, refluxing a lower draw-off stream including an alcohol from the first layer separator into the first reactor; and supplying an upper draw-off stream of at least one reactor of second to and nth reactors into each of the layer separators, splitting a portion of the lower draw-off stream including the alcohol from each of the layer separators, and refluxing only a portion of the split stream into each of the reactors.

Embodiments described herein provide a method of tuning an electrical liquid separator, comprising providing a liquid mixture to a separator; electrically coupling a power unit to the liquid mixture inside the separator; applying a time-varying voltage from the power unit to the liquid mixture; increasing a voltage applied to the liquid mixture from the power unit from a first voltage to a second voltage; detecting an inflection point in a current from the power unit; setting a voltage output range of the power unit to encompass a voltage at which the inflection point was detected.

The continuous liquid separation is a continuous liquid separating apparatus that separates a first liquid and a second liquid that is immiscible to the first liquid and has a higher specific gravity than the first liquid, and includes: a liquid separating tank configured to contain a liquid, and be supplied with a liquid mixture of the first liquid and the second liquid, and including a first discharge portion on a lower side thereof and a second discharge portion disposed at a position higher than the first discharge portion, a valve configured to open/close the first discharge portion, a first sensor configured to detect a first water level of the liquid mixture contained in the liquid separating tank, the first water level being lower than the second discharge portion, and a second sensor configured to detect a second water level of the liquid mixture contained in the liquid separating tank.