Systems and methods for filtering materials from biologic fluids are discussed. Embodiments may be used to filter cerebrospinal fluid (CSF) from a human or animal subject. In an example, CSF is separated into a permeate and retentate using a tangential flow filter. The retentate is filtered again and then returned to the subject with the permeate. During operation of the system, various parameters may be modified, such as flow rate and waste rate.

A method for fractionating a sulfuric acid process stream having at least 1 wt % sulfuric acid, using a treatment system comprising three filtration assemblies each having membranes that are suitable to pass less than 10% salt in a standard test such that average passage of sulfuric acid from the first and third filtration assemblies is less than 30% and average passage of sulfuric acid from second filtration assembly is more than 70%. The system produces a fraction of the stream with a pH between 4 and 10, and a second fraction that contains at least 20 weight percent of sulfuric acid.

Liquid solution concentration systems, and related methods, are generally described. In some embodiments, the system is an osmotic system comprising a plurality of osmotic modules. For example, the osmotic system can comprise a feed osmotic module configured to produce an osmotic module retentate outlet stream having a higher concentration of solute than the retentate inlet stream transported to the feed osmotic module. The osmotic system can also comprise an isolation osmotic module fluidically connected to the feed osmotic module. The osmotic system can also optionally comprise a purification osmotic module fluidically connected to the feed osmotic module and/or the isolation osmotic module. Certain embodiments are related to altering the degree to which the feed osmotic module retentate outlet stream is recycled back to the retentate-side inlet of the feed osmotic module during operation. Additional embodiments are related to the manner in which the retentate-side effluent from the isolation osmotic module is distributed among the system modules during operation.

Water deionization systems based on electrochemical water desalination or softening using a capacitive or intercalative deionization devices including a stack of electrochemical cells. Each cell includes first and second electrodes and an ion exchange membrane. Each cell includes inlet and outlet channels with control valves that control the separation of the source water into brine (e.g., concentration) and clean water (e.g., purification) streams. The deionization device or module may include multiple electrochemical cells connected electrically in series, parallel or a combination of both. The cells may also be in serial, parallel, or combined fluid communication. The output water of one or more streams from each cell or collection of cells may be recirculated and combined with one or more input water streams to improve the electrochemical energy efficiency of the cells. The electrochemical cells at different rows may have varying electrode thickness, area and loading of the active material.

The present invention provides a novel floating and renewable energy-powered desalination vessel, which also functions as a wind turbine generator and wave energy generator platform. With energy derived from the wind and waves, the vessel performs reverse osmosis within a vertically positioned cylindrical section extending below a buoyancy chamber. The cylindrical section contains reverse osmosis membranes located above a seawater screening and filtration system, which serve as ballast. The entire vessel and power systems are configured to have the center of mass below the center of buoyancy, forming a vertically stable floating structure with minimum pitch, roll, and wave heave in high sea states. The electric power generated is utilized internally to produce desalinated water or hydrogen from the desalinated water's electrolysis, power an onboard data center, or power delivery to a shoreside power grid. In addition to a wind turbine generator and a wave energy generator, a photovoltaic array or a marine current generator may be utilized to power these applications. Alternatively, the desalination vessel operates with the assistance of shore-based power provided by cable.

A high salinity feed water such as seawater is treated to produce a reverse osmosis (RO) concentrate and an RO permeate. Optionally, some or all of the RO concentrate may be filtered to produce a nanofiltration (NF) permeate. Optionally, some feed water can also be filtered to produce NF permeate without first being concentrated by RO treatment. The NF permeate, or a blend of the RO permeate and NF permeate, may be used to produce a product water for injection into an oil-bearing reservoir to enhance oil recovery. Optionally, the product water may have salinity greater than the feedwater, or at least 30 g/L. The product water may have hardness of less than 20 mg/L.

A system for producing steam includes a source of superheated water with superheated water output; a membrane filtration system in fluid communication with the superheated water output and including a membrane filter with a permeate side and an opposing retentate side. The membrane filter includes a separation membrane constructed to reject organic molecules. The system may be used for removing organic compounds, such as anti-corrosion agents or contaminants, from superheated water to produce steam. A method for producing steam includes directing a cross-flow of heated pressurized water including a first concentration of an organic compound across a membrane filter. The membrane filter includes a separation membrane constructed to reject the organic compound; and one or more support layers adjacent the separation membrane. A steam permeate including a second concentration of the organic compound is collected, where the second concentration is lower than the first.

A detonator positioning device for use with a detonator in a perforating gun assembly is described. The detonator positioning device is configured for electrically contactably forming an electrical connection within the perforating gun housing by contact. The detonator positioning device includes a body having a first end, a second end, and a central bore extending between the first and second ends. The central bore is adapted for receiving one or more electrically contactable components of a detonator. The detonator positioning device aligns at least one of the one or more electrically contactable components to form an electrical connection with a bulkhead assembly.

A filtering time control method includes testing water quality to obtain a water quality status value, determining whether a current filtration meets requirements. Based on whether the current filtration meets the requirements, setting a duration of the next filtering based on the current filtration duration. Adaptive adjustment of the duration of filtration may ensure a filtering effect while saving water resources.

Membrane distillation (MD) systems include at least two MD modules arranged in series, each of at least two MD modules including a condensing media inlet operable to receive a condensing media and a condensing media outlet, a feed inlet operable to receive a feed media and a feed outlet, and a first heating element positioned and operable to heat a feed prior to or upon introduction of the feed to a first of the at least two MD modules, wherein a stream exiting the feed outlet of the first of the at least two MD modules is introduced to the second of the at least two MD modules. Other MD systems include at least two MD modules arranged in parallel.