A cooling device for cooling a fluid comprises a vertical cooling tower, into an upper area of which the fluid to be cooled is fed and from a lower area of which the cooled fluid is discharged. The fluid in the cooling tower is cooled by a cooling gas flowing from the bottom to the top. At least one installation in which the fluid is conducted is provided in the gas space of the cooling tower through which cooling gas flows. Each installation comprises at least one fluid channel that is separated at least in part from the gas space of the cooling tower by a fluid-tight membrane wall that is permeable to vapor on both sides.

Provided is a moisture permeable filter medium formed by laminating a hydrophobic layer having hydrophobicity and a hydrophilic layer having hydrophilicity together, in which one of the hydrophobic layer and the hydrophilic layer is composed of a PTFE porous film formed using PTFE, and the other of the hydrophobic layer and the hydrophilic layer is composed of an air permeable sheet to which air is permeable.

A process for separating carbon dioxide from a fluid containing carbon dioxide, NO.sub.2, and at least one of oxygen, argon, and nitrogen comprises the steps of separating at least part of the fluid into a carbon dioxide enriched stream, a carbon dioxide depleted stream comprising CO.sub.2 and at least one of oxygen, argon, and nitrogen and a NO.sub.2 enriched stream and recycling said NO.sub.2 enriched stream upstream of the separation step.

A fluid filter and method for filtering fluid feed using the fluid filter is described. The fluid filter comprises an upper disk plate having a first compartment spaced apart and placed parallel to a lower disk plate having a second compartment. The feed fluid enters the first compartment in a first vortex pattern in a first direction at a first temperature, and a permeate fluid enters the second compartment in a second vortex pattern in a second direction opposite the first direction at a second temperature, wherein the second temperature is lower than the first temperature. A hydrophobic, vapor permeable membrane positioned between the upper disk plate and the lower disk plate allows vapor to pass from the first compartment to the second compartment having the permeate fluid, thus filtering the feed fluid.

A process for separating components or a fluid mixture using membranes comprising a selective layer made from copolymers of an amorphous per fluorinated dioxolane and a fluorovinyl monomer. The resulting membranes have superior selectivity performance for certain fluid components of interest while maintaining fast permeance compared to membranes prepared using conventional perfluoropolymers, such as Teflon® AF, Hyflon® AD, and Cytop®.

Provided are a method of and a device for purifying isopropyl alcohol. Water may be effectively removed from a feed including water and isopropyl alcohol while consuming a minimum amount of energy, and therefore, a high-purity isopropyl alcohol may be obtained.

Described herein is a crosslinked graphene and biopolymer (e.g. lignin) based composite membrane that provides selective resistance for gases while providing water vapor permeability. Methods for making such membranes, and methods of using the membranes for dehydrating mixtures, are also described.

A method for controlling a membrane distillation system includes determining whether there is a day time or a night time at a location of a solar collector system associated with the membrane distillation system; applying a first control mode during the day time to a flow velocity of a feed used by the membrane distillation system; and applying a second control mode, different from the first control scheme, during the night time, to the feed. The first control scheme is a model-free mode.

The present invention provides a separation membrane suitable for separating water from a liquid mixture containing an alcohol and water. A separation membrane 10 according to the present invention contains polyimide including a structural unit represented by formula (1). A is a linking group having a solubility parameter, in accordance with a Fedors method, of more than 5.0. B is a linking group having a solubility parameter of more than 8.56. R.sup.1 to R.sup.6 each are independently a hydrogen atom, a halogen atom, a hydroxyl group, a sulfonic group, an alkoxy group having 1 to 30 carbon atoms, or a hydrocarbon group having 1 to 30 carbon atoms. Ar.sup.1 and Ar.sup.2 each are a divalent aromatic group.

The present invention provides a separation membrane suitable for separating water from a liquid mixture containing an alcohol and water. A separation membrane 10 according to the present invention contains polyimide including a structural unit represented by formula (1). A is a linking group having a solubility parameter, in accordance with a Fedors method, of more than 5.0. B is a linking group having a solubility parameter of more than 8.56. R.sup.1 to R.sup.6 each are independently a hydrogen atom, a halogen atom, a hydroxyl group, a sulfonic group, an alkoxy group having 1 to 30 carbon atoms, or a hydrocarbon group having 1 to 30 carbon atoms. Ar.sup.1 and Ar.sup.2 each are a divalent aromatic group.