What is disclosed is a mass selective fluid bandpass filter. This filter provides for selecting gas molecules of a specific mass from a gas sample containing molecules of two or more mass species. This filter provides a means of operation of a selecting a predetermined gas from a group of gases or an atmosphere. The mass selective fluid bandpass filter consists of quartz glass, of either natural or manmade origin. This provides method of removing a predetermined gas from the group consisting of: .sup.1H.sub.2, .sup.1H.sup.2H, .sup.2H.sub.2, .sup.1H.sup.3H, .sup.2H.sup.3H, .sup.3H.sub.2, .sup.1H.sub.2O, .sup.1H.sup.2HO, .sup.2H.sub.2O, .sup.1H.sup.3HO, .sup.2H.sup.3HO, .sup.3H.sub.2O, .sup.3He, .sup.4He, O.sub.2, O.sub.3, .sup.12CO.sub.2, .sup.13CO.sub.2, .sup.14CO.sub.2, CO, N.sub.2, NO, NO.sub.2, NO.sub.x, SiO.sub.2, FeO, Fe.sub.2O.sub.3, SiF.sub.4, HF, NH.sub.3, SO.sub.2, SO.sub.3, H.sub.2SO.sub.4, H.sub.2S, .sup.35Cl.sub.2, .sup.37Cl.sub.2, F.sub.2, Al.sub.2O.sub.3, CaO, MnO, P.sub.2O.sub.5, phenols, volatile organic compounds, and peroxyacyl nitrates.

An acidic gas separation device includes: a first separation device which has an inorganic separation membrane and is configured to separate a gaseous hydrocarbon fluid containing an acidic gas into a first gaseous fluid having a large acidic gas content and a second gaseous fluid having a smaller acidic gas content than the first gaseous fluid by the inorganic separation membrane; and a second separation device which has an organic polymer separation membrane and is configured to separate the second gaseous fluid into a third gaseous fluid having a large acidic gas content and a fourth gaseous fluid having a smaller acidic gas content than the third gaseous fluid by the organic polymer separation membrane.

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.

In one aspect, a modular filter assembly for filtering fluid that flows in a flow direction therethrough is disclosed. The assembly includes a first housing section having a first filter element; a second housing section having a second filter element; and a connector disposed between the first and second housing sections. A housing includes the first housing section, the connector, and the second housing section. The flow direction is through the first and second filter elements in series.

The present invention relates to separation methods and systems for converting high concentrations of animal wastes into useful products, wherein the separation of the desired useful products is conducted with a cross-flow filtration system having the ability to the separate desired useful energy and/or products from both viscous and non-viscous medium.

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.

Methods and apparatus for onsite generation of acid and base solutions for cleaning purposes through the utilization of bipolar membrane electrodialysis (BPED) are described. The methods eliminate the need to s store large quantities of acids and bases onsite or to transport the acid and base solutions to the cleaning site. A method of recycling substantially neutralized waste salt solutions into acid and base solutions for additional cleaning, thus decreasing the amount of waste salt discharged to the environment, also is described.

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.

A system and method for producing from saline source water a product containing an increased ratio of multi-valent ions to mono-valent ions, which includes multiple nanofiltration units arranged to selectively remove mono-valent ions from the water fed into each nanofiltration stage in the nanofiltration permeate stream while retaining multi-valent ions in the nanofiltration reject stream. The rate at which the increase in the multi-valent ion- to mono-valent ion ratio is obtained may be enhanced by introduction of lower salinity water into the nanofiltration reject between stages, and by recirculating a portion of downstream nanofiltration reject flow into an upstream nanofiltration unit. The enhanced multi-valent ion product is suitable for multiple uses, including irrigation of plants and remineralization of desalinated water. The relative concentrations of the multi-valent ions in the product may be adjusted, for example by selection of nanofiltration membrane technologies which have higher or lower rejection for specific multi-valent ions.