The present application relates to a preparation method for recycling inorganic salt in printing and dyeing wastewater and comprises the following process steps: S1, performing impurity removal, softening, COD removal and decoloration on reverse osmosis (RO) membrane concentrated water to obtain pretreated wastewater; S2, performing two-stage electrodialysis on the wastewater obtained in step S1: returning fresh water obtained in a first-stage electrodialysis desalination chamber to a front end of the RO process, and taking saline water obtained in a concentration chamber as raw water of a second-stage electrodialysis desalination chamber and a second-stage electrodialysis concentration chamber; and returning the fresh water obtained by the second-stage electrodialysis desalination chamber to the first-stage electrodialysis concentration chamber; and S3, dealkalizing the concentrated saline water obtained in the step S2 and then adjusting the pH value to obtain concentrated saline water capable of being reused for cloth dyeing in a printing and dyeing mill.

An electrochemical device comprises a first type of membrane disposed between first and second reservoirs containing an input solution, and a second type of membrane, different from the first type, is disposed between a first redox-active electrolyte chamber and the first reservoir and disposed between a second redox-active electrolyte chamber and the second reservoir. The first type of membrane and one of the second type of membranes form a membrane pair and the pair has an area specific resistance below y=5065.3x.sup.3−1331.1x.sup.2+90.035x+39 Ohm cm.sup.2 when the pair is equilibrated in an electrolyte and for at least part of a range where 0<x<0.4 and x is the mass fraction of salt in the electrolyte.

An unmanned aerial vehicle (“UAV”) system for fluid transport includes a UAV having a fluid chamber configured to transport a fluid, a processor, and a memory. The memory includes instructions which, when executed by the processor, may cause the system to receive a first location for collecting or releasing a fluid, determine a fluid level of the fluid chamber, and transport the fluid by the UAV to the first location based on the determined fluid level.

An unmanned aerial vehicle (“UAV”) system for fluid transport includes a UAV having a fluid chamber configured to transport a fluid, a processor, and a memory. The memory includes instructions which, when executed by the processor, may cause the system to receive a first location for collecting or releasing a fluid, determine a fluid level of the fluid chamber, and transport the fluid by the UAV to the first location based on the determined fluid level.

A method of electrochemically treating a hydrocarbon-bearing formation is provided. The method includes electrochemically treating an aqueous fluid to provide a first fluid having a first electrochemical potential and a second fluid having a second electrochemical potential. The first electrochemical potential the second electrochemical potential have opposite signs. The method then includes introducing an amount of the first fluid into the hydrocarbon bearing formation, and then an amount of a spacer fluid is introduced into the hydrocarbon-bearing formation. An amount of the second fluid may be optionally introduced into the formation. The steps of introducing the fluids are repeated until an end point is reached. A system for electrochemically a hydrocarbon-bearing formation is also provided.

The invention relates to a method for removing and obtaining carbon dioxide from ambient air, comprising the continuous execution of the following steps: a) bringing ambient air into contact with an aqueous solution of at least one alkali metal or alkaline earth metal for the purpose of absorbing the carbon dioxide into the solution, forming the bicarbonate or carbonate of the at least one metal; b) electrodialysis of the resulting solution using a combination of bipolar ion-exchange membranes and ion-exchange membranes that are selective for mono- and multivalent anions to obtain one solution enriched in (bi-)carbonate anions and one solution depleted in (bi-)carbonate anions, wherein the solution depleted in (bi-)carbonate anions is recycled to step a); c) thermal desorption of the carbon dioxide from the solution, obtained in step b), enriched in (bi-)carbonate anions by means of steam stripping in order to obtain a carbon dioxide-steam mixture and a solution depleted in CO.sub.2 which is recycled to step (b), wherein a pH is set there of between 7 and 8.5 or between 8 and 9.5; and d) removing water from the obtained carbon dioxide-steam mixture by cooling to condense the steam, and possibly further drying of the carbon dioxide.

Electrodialysis cell systems for water deionization is provided. Also provided are methods for using the electrodialysis cell systems. The cells use the forward and reverse reactions of a redox mediator and the combined operations of a deionization cell and an ion-accumulation cell to enable sustainable deionization with a significantly decreased operating voltage, relative to conventional deionization cells. The cells have applications in seawater desalination, water purification, and wastewater treatment.

A monovalent selective ion exchange membrane is disclosed. The membrane includes a polymeric microporous substrate, a cross-linked ion-transferring polymeric layer on a surface of the substrate, and a charged functionalizing layer covalently bound to the ion-transferring layer. A method of producing a monovalent selective cation exchange membrane is also disclosed. The method may include chemically adsorbing a styrene intermediate layer to a cross-linked ion-transferring polymeric layer on a surface of a polymeric microporous substrate, chlorosulfonating the styrene intermediate layer to attach a sulfonyl chloride group layer, aminating the sulfonyl group layer to attach an amine group layer, and functionalizing the amine group layer with a charged compound layer to produce the cation exchange membrane. Water treatment systems including the monovalent selective cation exchange membrane and methods of facilitating water treatment including providing the monovalent selective cation exchange membrane are also disclosed.

A monovalent selective ion exchange membrane is disclosed. The membrane includes a polymeric microporous substrate, a cross-linked ion-transferring polymeric layer on a surface of the substrate, and a charged functionalizing layer covalently bound to the ion-transferring layer by an acrylic group. A method of producing a monovalent selective cation exchange membrane is also disclosed. The method may include chemically adsorbing an acrylic intermediate layer comprising a chlorosulfonated methacrylate group to a cross-linked ion-transferring polymeric layer on a surface of a polymeric microporous substrate, aminating the chlorosulfonated methacrylate group to attach an amine group layer, and functionalizing the amine group layer with a charged compound layer to produce the cation exchange membrane. Water treatment systems including the monovalent selective cation exchange membrane and methods of facilitating water treatment including providing the monovalent selective cation exchange membrane are also disclosed.

A method for extracting and purifying Dendrobium officinale polysaccharides comprises following steps: (1) fully disperse Dendrobium officinale powder in pure water to obtain crude liquid; (2) removing insoluble impurities from the crude liquid through a microfiltration membrane to obtain permeate 1 and retentate 1; (3) performing macroporous ultrafiltration treatment of the permeate 1 and collect permeate 2 and retentate 2; (4) adding an aqueous solution of edible alkali metal inorganic salt to the retentate 2, fully stirring and dissolving to obtain polysaccharide crude liquid, performing macroporous ultrafiltration treatment and collecting permeate 3 and retentate 3; (5) combining the permeate 2 and permeate 3, adding the combined permeate into an electrodialysis device for desalination, and collecting dilute solution and concentrated solution; (6) performing microporous ultrafiltration treatment of the dilute solution and collect retentate 4 and permeate 4; (7) carrying out freeze-drying of the retentate 4 to obtain Dendrobium officinale polysaccharides.