A water treatment membrane washing apparatus includes two ozone dissolving tanks for storing filtrate generated by filtering raw water through a water treatment membrane and gas aspirators provided for the respective ozone dissolving tanks, for mixing the filtrate with ozone gas supplied from an ozone supply unit to generate ozone gas containing filtrate, and is configured such that waste ozone gas generated in one of the ozone dissolving tanks is aspirated by the gas aspirator provided for the other ozone dissolving tank. After the filtrate from the raw water is pretreated by being mixed with the waste ozone gas in the aspirator, the pretreated filtrate is mixed with the ozone gas in the other ozone dissolving tank until it reaches a predetermined concentration. The ozone gas containing filtrate is supplied from the secondary side of the water treatment membrane to the primary side thereof to wash the eater treatment membrane.

A water filtration system is provided comprising first and second banks of water filter assemblies, wherein the system is arranged to provide filtered water from one bank of water filter assemblies while using some of the filtered water to reverse flush the other bank of water filtration assemblies. A method of filtering water by passing it through the system is also provided.

A filtration system has a filter element with a filtration membrane, a feed inlet and a concentrate outlet on a first side of the membrane and a permeate outlet on a second side of the membrane. A feed line with a feed shutoff valve is in fluid communication with the feed inlet, and a concentrate return line with a concentrate shutoff valve is in fluid communication with the concentrate outlet. A feed pump is in fluid communication with the feed inlet via the feed line and the feed shutoff valve, and a backwash pump is in fluid communication with the permeate outlet. In a priming phase of a backwash operation, the feed shutoff valve and the concentrate shutoff valve are closed and the backwash supply is operable to deliver fluid to the filtration element and equalize pressure between the first side and the second side of the filtration membrane.

A method for cleaning a filter membrane in which at least 2 types of cleaning water containing oxidizing agents are prepared, and the filter membrane is cleaned using the cleaning water in an ascending order of the oxidizabilities of the oxidizing agents. Moreover, an apparatus for cleaning a filter membrane of the present invention comprises a means for cleaning the filter membrane using at least 2 types of cleaning water containing oxidizing agents, and the filter membrane is cleaned using the cleaning water in an ascending order of the oxidizabilities of the oxidizing agents. The method and the apparatus for cleaning a filter membrane can efficiently remove polluting substances adhered to a filter membrane while reducing the amounts of oxidizing agents and water to be used, and can maintain the filtration performance for a long period of time.

This specification describes membrane based filtration and softening systems and methods. A system has a microfiltration or ultrafiltration (MF/UF) membrane unit upstream of a nanofiltration or reverse osmosis (NF/RO) membrane unit, optionally with no intermediate tank. In some cases, the system and method may be used with feed water provided at municipal line pressure to the membranes. NF/RO permeate is collected in a tank and then pumped to a header. Treated water may be drawn from the header for use or recycled to the system, for example to backwash or flush one or both of the membrane units. In a combined process, NF/RO permeate flushes the feed side of the NF/RO unit and then backwashes the MF/UF unit. In another process, the MF/UF unit and NF/RO unit are filled with NF/RO permeate before being placed in a standby mode.

A connector for connecting a dialyzer to a hole in a side wall of a water pipe, the connector including a connector body including a cavity crossing the connector body from a first end of the connector body to a second end, for enabling water flow from the first end to the second end, wherein the cavity at the first end is shaped and sized for pressing onto a port of a dialyzer, and the cavity at the second end is shaped and sized for pressing into a hole in a side wall of a water pipe. In a water filtration system including dialyzers for water filtration, a method of cleaning a dialyzer including providing clean water from a clean water output of one first dialyzer to a clean water output of one second dialyzer, to backwash the second dialyzer. Related apparatus and methods are also described.

An integrated system comprising a closed circuit desalination (CCD) unit with membrane cleaning (MC) means wherein the latter are activated briefly (8 minute) on a frequent basis, once a day or several days, for removal of fouling and/or scaling deposits off membrane surfaces created during the elapsed time interval and thereby, avoiding their accumulation and the need of CIP. MC proceeds in a tie-line sequence with different reagents solution in permeate known to affect the removal of common fouling and/or scaling constituents from membrane surfaces such as organic and/or bioorganic substances and/or inorganic scaling constituents including silica and polymerized silica coatings with either metal hydroxides or organic substances. Removal of silica containing deposits from membrane surfaces proceeds by a brief exposure to diluted hydrofluoric acid solution in permeate in the absence of interfering metal ions (e.g., Ca). The MC sequence incorporate both reverse osmosis (RO) and direct osmosis (DO) principles, the former to enable an effective contact of the cleaning reagents with membrane surfaces and the latter for inside-out backwash of semi-permeable membranes with permeate.

The fully computerized inventive system should enables a near perfect removal of all fouling and/or scaling constituents off membrane surfaces at an early stage on a regular basis before their accumulation and thereby, preventing the need for CIP and avoiding irreversible damage membranes as result of accumulation of irremovable fouling constituents.

A fixed or mobile water treatment system comprises a primary screening tank that filters wastewater to remove inorganic and organic pollutants from the wastewater, and includes an electro-coagulation unit that provides an electrical charge to wastewater exiting the primary screening tank, ultraviolet light and oxidation processes in one or more settling tanks that remove pollutants from the wastewater, and one or more filters that remove pollutants from the wastewater.

A medical monitoring device for monitoring electrical signals from the body of a subject is described. The medical monitoring device monitors electrical signals originating from a cardiac cycle of the subject and associates each cardiac cycle with a time index. The medical monitoring device applies a forward computational procedure to generate a risk score indicative of hyperkalemia, hypokalemia or arrhythmia of the subject. The medical monitoring device can adjust the forward computational procedure based upon clinical data obtained from the subject.

Apparatus and method for semi-permeable membrane cleaning in particular, applying series of pulsed water stroke, made simultaneously with osmosis backward flow causing superposed membrane directional shaking and fouling detachment. Pulsed water stroke provided by water stroke generator as several momentum sharp changes in gauge pressure and induce velocity pulse of residual brine flow. The pulsed water strokes ideally induce resonance in the membrane. Osmosis backward wash may be provided either by injection for predetermined injection time, additional solution selected in such way that net driving pressure be-comes opposite to normal osmotic operation thereby providing a backward flow of permeate towards to the side opposite to normal operation mode, so as to lift said foulant, or by throttling permeate exiting from the permeate enclosure, until the net driving pressure value become equal to zero, during application of precise synchronized and opposing brine and permeate pressure strokes thereby providing a plurality of quick RO-FO-RO process changes. These procedures allow a membrane to be kept continuously clean and operate at higher recovery.