A system and a method for removing gas field chemicals from a feed stream are provided. An exemplary method includes performing a forward osmosis on a feed stream including gas field chemicals to form a concentrated feed stream, and treating the concentrated feed stream in an electrochemical process to form treated water.

The application pertains to processes for producing components such as an alkali hydroxide and a carboxylic acid. The processes generally comprise reacting a component comprising calcium carbonate, or calcium sulfide, or calcium hydroxide, or calcium oxide, or calcium weak acid, or any combination thereof with a component comprising a carboxylic acid to form a component comprising a calcium carboxylate and a component comprising carbon dioxide, or hydrogen sulfide, or water, or any combination thereof. At least a portion of the formed calcium carboxylate is reacted with a component comprising an alkali sulfate to form a component comprising an alkali carboxylate and a component comprising calcium sulfate. At least a portion of the formed alkali carboxylate is electrochemically reacted to form a component comprising an alkali hydroxide and a component comprising a carboxylic acid.

The disclosure relates to systems, devices, and methods for flow control in a reverse osmosis filtration system, such as within a medical device. The systems, devices, and methods can respond to changes in permeate flow rate and solute concentration by adjusting feed water and concentrate water rates. Multiple feedback loops adjust parameters to meet water flow rate and purity requirements.

The application pertains to processes for producing components such as an alkali hydroxide and a carboxylic acid. The processes generally comprise reacting a component comprising calcium carbonate, or calcium sulfide, or calcium hydroxide, or calcium oxide, or calcium weak acid, or any combination thereof with a component comprising a carboxylic acid to form a component comprising a calcium carboxylate and a component comprising carbon dioxide, or hydrogen sulfide, or water, or any combination thereof. At least a portion of the formed calcium carboxylate is reacted with a component comprising an alkali sulfate to form a component comprising an alkali carboxylate and a component comprising calcium sulfate. At least a portion of the formed alkali carboxylate is electrochemically reacted to form a component comprising an alkali hydroxide and a component comprising a carboxylic acid.

Described herein is an ion pump system implementing an electronic ratchet mechanism produced by modulating a spatially varying electric potential distribution that can result in a net ionic current and voltage. The ion pumping membrane system includes an ion-permeable layer that can also be integrated with ion-selective membranes. The electric potential distribution within the ion-permeable layer is modulated through external stimuli. When immersed in solution, ions within the ion-permeable layer experience a time varying, spatially asymmetric electric field distribution resulting in ratchet-driven direct ion pumping, which can be used in applications such as desalination.

A carbon dioxide electrolytic device includes: a carbon dioxide electrolysis cell having a cathode and an anode flow path, a cathode, an anode, and a first diaphragm; a first current regulator to supply a first current; a first gas/liquid separator to separate a first fluid from the anode flow path into a first liquid and gas; an electrodialysis cell having, first and second electrodes, first to fourth rooms, and second to fourth diaphragms; a second current regulator to supply a second current; at least one detector out of a first detector to detect a flow rate of the first gas or a concentration of carbon dioxide in the first gas, and a second detector to detect a pH or a concentration of at least one ion in the first fluid; and a first controller to regulate a second current, in accordance with at least one detection signal.

A carbon dioxide electrolytic device includes: a carbon dioxide electrolysis cell having a cathode and an anode flow path, a cathode, an anode, and a first diaphragm; a first current regulator to supply a first current; a first gas/liquid separator to separate a first fluid from the anode flow path into a first liquid and gas; an electrodialysis cell having, first and second electrodes, first to fourth rooms, and second to fourth diaphragms; a second current regulator to supply a second current; at least one detector out of a first detector to detect a flow rate of the first gas or a concentration of carbon dioxide in the first gas, and a second detector to detect a pH or a concentration of at least one ion in the first fluid; and a first controller to regulate a second current, in accordance with at least one detection signal.

An apparatus (100) for producing an acidic aqueous solution includes: an electrodialyzer (110) that has a monovalent ion perm-selective ion-exchange membrane and separates wastewater containing chloride ions and alkali metal ions into electrodialysis concentrated water and electrodialysis diluted water by an electrodialysis treatment; an electrolyzer (120) includes an anode that that electrolyzes the electrodialysis concentrated water to produce an acidic aqueous solution; and a first circulator (13) that circulates at least some of the acidic aqueous solution to the wastewater supplied to the electrodialyzer (110), and that adjusts a pH of the wastewater supplied to the electrodialyzer to 3 to 9.

Disclosed are a system and methods for producing lithium hydroxide directly from natural brine by an electrochemical approach. In one example version of the system, an electrochemical cell operates in two states. In one state, lithium cations (Li.sup.+) intercalate into a first electrode from the brine, and sodium cations (Na.sup.+) deintercalate from a second electrode into the brine. In another state, lithium cations deintercalate from the first electrode into a dilute lithium hydroxide (LiOH) solution, and sodium cations intercalate to the second electrode from a concentrated sodium hydroxide (NaOH) solution. Hydroxide anions (OH.sup.) transport through an anion exchange membrane to combine with lithium cations (Li.sup.+) to form LiOH, continuously increasing its concentration.

The present disclosure relates to a water purification apparatus that comprises a reverse osmosis device, RO-device, producing a purified water flow and to a corresponding method. The proposed method comprises detecting at least one fluid property of purified water in the purified water path and regulating a flow rate of water in the recirculation path to fulfil one or more predetermined criteria of the purified water in the purified water path, based on the at least one detected fluid property. The present disclosure also relates to a computer program and a computer program product implementing the method.