An air channel membrane distiller (1) comprises a hot surface (12), a cooling section (20) and a hydrophobic membrane (30). The hot surface and the hydrophobic membrane define a sealed evaporation channel (40). A surface (22) of the cooling section and the hydrophobic membrane define a sealed condensation channel (50). A water supply tubing (42) is connected to the evaporation channel. A water discharge tubing (46) is connected to the evaporation channel. A purified-water discharge tubing (56) is connected to the condensation channel. The surface of the cooling section is given a temperature lower than a temperature of water in the evaporation channel. A gas supply arrangement (60) for inert gas comprises a heater (62). A gas pipe system (64) is arranged to a gas inlet (55) of the condensation channel for enabling flushing of at least the condensation channel with the inert gas.

A purification device for water has a housing with a longitudinal axis, an upper and a lower end and a substantially round cross section. The device includes a first receptacle, arranged parallel to the longitudinal axis of the housing, for a first purification medium, and a second receptacle, which is also arranged parallel to the longitudinal axis of the housing, for a second purification medium. The receptacle for the second purification medium is arranged eccentrically with respect to the longitudinal axis of the housing.

A pure water production method for producing pure water by decarboxylating water to be treated under acidic conditions and then deionizing the result by using a reverse osmosis membrane separation device, the pH of inflow water flowing into the reverse osmosis membrane separation device and the water quality of permeated water of the reverse osmosis membrane separation device being measured, and the pH of the inflow water being adjusted on the basis of the measured pH and water quality so that the water quality of the permeated water is within a prescribed range, wherein the pH of the inflow water is changed by a predetermined width, and an operation condition adjusting step is performed for adjusting the pH of the inflow water by comparing the(average value before the water quality change average value after the water quality change.

A flow through fluid purification device (1) comprising a container (5) arranged such that fluid can flow through a volume (8) of the container (5) from an inlet (3) to an outlet (7), and an inner cylinder (10a) inserted or insertable into the volume (8) of the container (5) and defining an interface wall (11) permeable for radiation with a wavelength in the UV-range, preferably between 150 nm and 200 nm, wherein the container (5) includes plurality of axially arranged cylinder parts (5b,5c,5d,5e) connected to each other by welding to form an outer cylinder assembly (5a).

An electrostatic purification device includes a purification tank housing configured to accommodate a fluid, a first electrode and a second electrode provided in the purification tank housing, a direct current (DC) power supply configured to apply a DC to the first electrode and the second electrode, a controller configured to monitor a current density between the first electrode and the second electrode, and determine whether purification is completed based on the current density, a first valve configured to control an introduction flow of the fluid into the purification tank housing, a second valve configured to control a discharge flow of the fluid from the purification tank housing, and a heat exchanger configured to cool the fluid accommodated in the purification tank housing.

According to various aspects and embodiments, a system and method for polishing ultrapure water (UPW) is disclosed. The water polishing system includes a source of ultrapure water (UPW), an ultrafiltration (UF) module having an inlet and a permeate outlet, a recirculation conduit communicating the permeate outlet with the inlet and forming a recirculation loop, a recirculation pump disposed along the recirculation conduit upstream from the inlet of the UF module and fluidly coupled to the source of UPW, a supply conduit fluidly coupled to the recirculating conduit and a demand source, the supply conduit positioned downstream from the permeate outlet, and a pressure control valve disposed along the recirculation conduit downstream from the supply conduit and configured to maintain pressure of permeate at a predetermined value.

A method and system of providing ultrapure water for semiconductor fabrication operations is provided. The water is treated by utilizing a free radical scavenging system. The free radical scavenging system can utilize actinic radiation with a free radical precursor compound, such as ammonium persulfate. The ultrapure water may be further treated by utilizing ion exchange media and degasification apparatus. A control system can be utilized to regulate a continuously variable intensity of the actinic radiation.

A method of producing water supersaturated with a gas includes drawing water from a water supply; filtering the water; purifying the water; disinfecting the water and neutralizing remaining biocontaminants; filtering the water to remove the neutralized biocontaminants; mineralizing the water; supersaturating the water with nanobubbles of a gas; and storing the water. A system for producing the supersaturated water includes a filter; a purification unit connected to an outlet of the filter; an ultraviolet treatment reservoir connected to an outlet of the purification unit; a second filter connected to an outlet of the UV treatment reservoir; a minerals addition unit connected to an outlet of the second filter; and a nanobubble generator connected to an outlet of the minerals addition unit. The water can be economically supersaturated at levels higher than 120%.

A specific resistance value adjustment apparatus includes: a hollow fiber membrane module; a module passing pipe which passes through the hollow fiber membrane module; a bypassing pipe which bypasses the hollow fiber membrane module; a liquid discharge pipe which communicates with the module passing pipe and the bypassing pipe through a joint portion; a first flow rate detection unit which detects a first flow rate of a liquid flowing to at least one of a liquid supply pipe and the liquid discharge pipe; a control valve which opens and closes the module passing pipe; and a control unit which sets an opening degree of the control valve in response to the first flow rate detected by the first flow rate detection unit.

A ultrapure water supply system 10 includes a pure water tank 16 provided vertically below a use point 30, a return pipe 32 through which ultrapure water is returned from the use point 30 to the pure water tank 16, a first pressure regulating valve 40 that is provided at a first position H1 of the return pipe 32 and adjusts a first pressure upstream of the first position H1 and a second pressure regulating valve 42 that is provided at a second position H2 downstream of the first position H1 and vertically below the first position H1 of the return pipe 32 and adjusts a second pressure downstream of the first position H1 and upstream of the second position H2.