A subsea multiphase fluid separation system has a gas separator for separating gas from a well stream containing oil. A water separation stage downstream of the gas separator has at least one dual pipe separator for separating water from the oil of the wellstream. A water treatment system for cleaning oil from water is produced by the water separation stage. On an oil outlet path, downstream of the or each dual pipe separator, there is an electrocoalescer and at least one second separator in series.

A method and an arrangement for removing amine(s) from a thickener overflow of a mineral processing plant. The method includes supplying the thickener overflow to an electrocoagulation unit and subjecting the thickener overflow to electrocoagulation in order to separate at least some of the amine(s) as an electrocoagulation overflow and in order to form a residual process water as an electrocoagulation underflow, and removing the electrocoagulation overflow. The method is free of all of the following: a coagulant, a flocculant, an adsorbent and an additional flotation chemical.

A method and an arrangement for removing amine(s) from a thickener overflow of a mineral processing plant. The method includes supplying the thickener overflow to an electrocoagulation unit and subjecting the thickener overflow to electrocoagulation in order to separate at least some of the amine(s) as an electrocoagulation overflow and in order to form a residual process water as an electrocoagulation underflow, and removing the electrocoagulation overflow. The method is free of all of the following: a coagulant, a flocculant, an adsorbent and an additional flotation chemical.

Systems and methods for treating produced water and/or flowback water from fracking operations include: an oil water separator; a first filter downstream of the oil water separator; and an electrocoagulation unit downstream of the first filter. Systems and methods can be used for producing a concentrated brine for use in industrial applications and a separate stream of fresh water

Methods of treating a fluid mixture include performing a first treatment on the mixture with electrochemically produced ions to separate an aqueous phase and a hydrophobic phase and performing a second electrochemical treatment on the separated aqueous phase to thereby remove aqueous contaminants from the aqueous phase wherein substantially laminar flow of fluid occurs between electrodes in the second electrochemical treatment.

Methods of treating a fluid mixture include performing a first treatment on the mixture with electrochemically produced ions to separate an aqueous phase and a hydrophobic phase and performing a second electrochemical treatment on the separated aqueous phase to thereby remove aqueous contaminants from the aqueous phase wherein substantially laminar flow of fluid occurs between electrodes in the second electrochemical treatment.

Managed ecosystems, methods for producing managed ecosystems and methods for using managed ecosystems for sequestering carbon dioxide are described herein. Produced water is obtained and purified to sustain a managed ecosystem with saline-tolerant vegetation. The managed ecosystem biologically sequesters carbon dioxide by photosynthetically absorbing carbon dioxide from the atmosphere and by decomposition into a layer of sediment on the ecosystem floor.

Managed ecosystems, methods for producing managed ecosystems and methods for using managed ecosystems for sequestering carbon dioxide are described herein. Produced water is obtained and purified to sustain a managed ecosystem with saline-tolerant vegetation. The managed ecosystem biologically sequesters carbon dioxide by photosynthetically absorbing carbon dioxide from the atmosphere and by decomposition into a layer of sediment on the ecosystem floor.

The present invention is directed to an electrochemical device for at least partially removing or reducing a target ionic species from an aqueous solution using faradaic immobilization, the electrochemical device including at least one first electrode and at least one second electrode with different void fraction and surface area properties, due to differences in void fraction (also referred to as void ratio) of the at least one first and the at least one second electrode, water flows through an electrode with a high porosity, while the aqueous solution does not flow through an electrode with a low porosity. The asymmetry of the electrodes provides a desired voltage distribution across the device, which equates to a different voltage at each electrode, to control the speciation of the target ionic species at the anode and the cathode.

A carbon fiber filter includes a center filter body and carbon fiber yarn wound around the center filter body. The center filter body is hollow and includes a water outlet. A surface of the center filter body is provided with at least one inverted triangular groove. A plurality of through holes are arranged in the groove. The through holes and the water outlet are in communication with a hollow inner cavity of the center filter body. The carbon fiber yarn is wound in the groove with a constant force to form a filter layer.