A spiral wound membrane module including a specialized endcap assembly including a connecting conduit defining a passageway extending radially inward from its outer periphery, and a differential pressure sensor connected to the passageway of the connecting conduit.

This invention uses multiple pairs of electrodes acting as electrical conductivity sensors that are secured at specific locations within spiral wound membrane elements and their interconnecting components of a reverse osmosis or nanofiltration pressure vessel. Each electrode pair might be attached to a wire cord to be inserted through and sealed against a vessel end cap into the permeate carrier tubes and interconnecting components of the membrane elements, or each electrode pair might be attached to a battery and a wireless transmitting device. Conductivity measurements from the sensors would be communicated to a microprocessor, which would evaluate each permeate conductivity measurement relative to other permeate conductivity measurements, as well as relative to derived or measured conductivities in the saline water in calculating a percent salt passage value specific to the location of each permeate sensor.

A reverse osmosis treatment device includes: a first pressure vessel for treating an untreated water to produce a primarily treated water and a first permeated water; a second pressure vessel for treating the primarily treated water to produce a secondarily treated water and a second permeated water; a first cleaning solution tank for storing a first cleaning solution for cleaning the first pressure vessel; and a second cleaning solution tank for storing a second cleaning solution for cleaning the second pressure vessel. Each of the first pressure vessel and the second pressure vessel has therein a reverse osmosis membrane element having a reverse osmosis membrane. The first cleaning solution tank is connected to the first concentrate outlet pipe of the first pressure vessel, and the second cleaning solution tank is connected to the inlet pipe for the primarily treated water of the second pressure vessel.

A reverse osmosis treatment device includes: a first pressure vessel for treating an untreated water to produce a primarily treated water and a first permeated water; a second pressure vessel for treating the primarily treated water to produce a secondarily treated water and a second permeated water; a first cleaning solution tank for storing a first cleaning solution for cleaning the first pressure vessel; and a second cleaning solution tank for storing a second cleaning solution for cleaning the second pressure vessel. Each of the first pressure vessel and the second pressure vessel has therein a reverse osmosis membrane element having a reverse osmosis membrane. The first cleaning solution tank is connected to the first concentrate outlet pipe of the first pressure vessel, and the second cleaning solution tank is connected to the inlet pipe for the primarily treated water of the second pressure vessel.

Embodiments of the present invention provide elements that are beneficial for use in fluid filtration. Embodiments provide elements that have variable feed spacer height, variable permeate spacer height, or both. The variable height allows flow properties to be matched to fluid volume as the filtration occurs.

A membrane separation unit can include a cartridge, at least one membrane disposed within the cartridge, at least one seal plate, and a sealing ring seated in an outer groove of the seal plate. The at least one seal plate can seal one end of the cartridge. The seal plate can have at least one venting hole that forms a passage between the interior of the cartridge and the outer groove. The sealing ring can have a cross-sectional shape that forms a circular venting path between the sealing ring and the seal plate. The sealing ring can include one or more grooves to allow fluid to vent into an annular space between a device housing and the membrane separation unit. The sealing ring can include an outer surface having, in cross-section, two flattened surfaces that form an angle of between 90° and 175° there between.

A membrane separation unit can include a cartridge, at least one membrane disposed within the cartridge, at least one seal plate, and a sealing ring seated in an outer groove of the seal plate. The at least one seal plate can seal one end of the cartridge. The seal plate can have at least one venting hole that forms a passage between the interior of the cartridge and the outer groove. The sealing ring can have a cross-sectional shape that forms a circular venting path between the sealing ring and the seal plate. The sealing ring can include one or more grooves to allow fluid to vent into an annular space between a device housing and the membrane separation unit. The sealing ring can include an outer surface having, in cross-section, two flattened surfaces that form an angle of between 90° and 175° there between.

A water treatment device is provided with a separation membrane device having a separation membrane for concentrating dissolved components and dispersed components from water to be treated and obtaining permeated water; a first deposit detecting unit provided in a non-permeated water branch line branched from a non-permeated water line for discharging non-permeated water in which dissolved components and dispersed components have been concentrated, using part of the non-permeated water that has branched off as a detection liquid, and having a first separation membrane for detection in which the detection liquid is separated into permeated water for detection and non-permeated water for detection; and first flow rate measuring devices for separated liquid for detection that measure the flow rates of one or both of the permeated water for detection and the non-permeated water for detection separated by the first separation membrane for detection.

A water treatment device is provided with a separation membrane device having a separation membrane for concentrating dissolved components and dispersed components from water to be treated and obtaining permeated water; a first deposit detecting unit provided in a non-permeated water branch line branched from a non-permeated water line for discharging non-permeated water in which dissolved components and dispersed components have been concentrated, using part of the non-permeated water that has branched off as a detection liquid, and having a first separation membrane for detection in which the detection liquid is separated into permeated water for detection and non-permeated water for detection; and first flow rate measuring devices for separated liquid for detection that measure the flow rates of one or both of the permeated water for detection and the non-permeated water for detection separated by the first separation membrane for detection.

Provided is a reverse osmosis treatment apparatus which decreases operation power by utilizing a back pressure caused by regulating an amount of permeated water. The reverse osmosis treatment apparatus includes a first pressure vessel for a primary treatment of untreated water, and a second pressure vessel for a secondary treatment of the water treated by the primary treatment, wherein a reverse osmosis membrane element having a reverse osmosis membrane or the plurality of reverse osmosis membrane elements are arranged in series along a water collection pipe in the first pressure vessel and the second pressure vessel. The first pressure vessel includes a first outlet pipe which discharges permeated water, and a permeated water flow control valve connected to the first outlet pipe and regulating a pressure in the first pressure vessel. An energy recovery apparatus is provided between the first outlet pipe and the permeated water flow control valve.