Selective removal of non-aromatic hydrocarbons from a xylene isomerization process for para-xylene production is accomplished using a membrane unit positioned within a xylene recovery loop. The membrane unit may include a one-stage or multi-stage (e.g., two-stage) membrane system and may be configured to separate a membrane unit product stream from a non-aromatics rich stream, which can be removed from the xylene recovery loop. The membrane unit may have a xylene permeance of about 60 gm/m.sup.2/hr/psi and a xylene to non-aromatic permeance ratio of about 15.

The present invention relates to novel cartridges and modules for separation of fluid mixtures, especially for gas separation, to a process for production thereof and to a method of use thereof.

Hollow fiber cartridges and components and methods of their construction.

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. The method may include the steps of withdrawing fluid comprising CSF, filtering the volume into permeate and retentate by passing the fluid through a tangential flow filter, and returning the permeate to the subject. During operation of the system, various parameters may be modified, such as flow rate.

Algae harvesting and cultivating systems and methods for producing high concentrations of algae product with minimal energy. In an embodiment, an algae harvesting method is provided for performing dead-end filtration in an algae harvesting system having at least one treatment tank defining a plurality of filtration stages including at least a first filtration stage and a second filtration stage. An algae medium is pulled through the hollow fiber membranes such that a retentate and a permeate are produced.

A inventive two-stage batch-CCD RO system includes two separate batch-CCD units of a different number of modules per stage with more modules in the first-stageN(1)>N(2). A two-stage batch-CCD process proceeds when both units execute parallel fixed flow variable pressure desalination sequences of same operational set-points [flux, module recovery and batch sequence recovery (R)], with brine of a former first-stage used as second-stage feed. In two-stage batch CCD RO systems of high N(1)/N(2) ratio whereby the relative production of permeates of the two stages complies to: (1)>>(2), most of the permeates are produced in the first-stage under mild conditions and contribute to the low energy and salinity of permeates of the entire process. Compared with the performance of a single-stage batch-CCD RO unit, a two-stage system of the same module-number will render a performance of super RO characteristics, unmatched by any existing RO methods.

The present invention relates to processes and systems for ammonia recovery and/or acid-gas separation. In some embodiments, a system for acid gas separation may be integrated with an ammonia abatement cycle employing a high temperature absorber. In some embodiments, a system for acid gas separation may employ a higher temperature absorber due to the lower energy consumption and cost of the integrated ammonia abatement cycle. Advantageously, heat may be recovered from the absorber to power at least a portion of any acid gas desorption in the process. Reverse osmosis or other membranes may be employed.

A filtration device includes a continuous first unit including a first membrane that separates a liquid into first permeated and non-permeated liquids, a first adjuster that adjusts a flow rate of the first permeated liquid to be substantially constant, and a first liquid scale that detects a liquid amount, a second unit including a second membrane that separates another liquid into second permeated and non-permeated liquids, a second adjuster that adjusts a flow rate of the second permeated liquid to be substantially constant, and a second liquid scale that detects another liquid amount, a first controller that controls the liquid amount in the first storage tank based on measurement values from continuous two first units or from the continuous first and second units, and a second controller that controls the another liquid amount based on a measurement value from the second unit.

The high water recovery hybrid membrane system for desalination and brine concentration combines nanofiltration, reverse osmosis and forward osmosis to produce pure water from seawater. The reject side of a nanofiltration unit receives a stream of seawater and outputs a brine stream. A permeate side of the nanofiltration unit outputs a permeate stream. A feed side of a reverse osmosis desalination unit receives a first portion of the permeate stream and outputs a reject stream. A permeate side of the reverse osmosis desalination unit outputs pure water. A draw side of at least one forward osmosis desalination unit receives the reject stream and outputs concentrated saline solution. A feed side of the at least one forward osmosis desalination unit receives a second portion of the permeate stream and outputs a dilute saline stream, which mixes with the first portion of the permeate stream fed to the reverse osmosis desalination unit.

A system and method for producing very high concentration brine streams from which commercially efficiently obtained minerals may be obtained is produced by a dual membrane brine concentrator system (DTRI Concentrator). The system includes a nano-filtration system which removes divalent ions from the seawater, a brine concentrator such as a hollow fine fiber forward osmosis system which receives and further concentrates the brine rejected from the nano-filtration system, a SWRO system which receives the NF system permeate and removes monovalent ions, and another brine concentrator which further concentrates the brine rejected from SWRO system. Various permeate and reject brine flow may be forwarded through the Dual Membrane Brine Concentrator system, and multiple stages of the system components may be used, to enhance brine concentration and improve system efficiency.