Methods of filtering a feed comprising a liquid or a gas for or during the production of electronics, nanosystems or ultrapure water include filtering said feed using at least one filter assembly, wherein said at least one filter assembly includes at least one isoporous block copolymer filtration membrane.

A system for treating a tetraalkylammonium hydroxide-containing liquid having a high-pressure type reverse osmosis membrane device concentrating a liquid to be treated containing tetraalkylammonium hydroxide at a concentration side, and a line for supplying the concentrated liquid to be treated by the reverse osmosis membrane device to an evaporator further concentrating the concentrated liquid to be treated.

The present invention relates to a method for manufacturing liquid calcium citrate (C.sub.12H.sub.14CaO.sub.14) or mono calcium citrate powder by using shells and application thereof and, more specifically, to a method for manufacturing liquid calcium citrate by using shell powder and citric acid and mono calcium by drying same, and application thereof.

A management method of a system for producing an ultrapure water, the system including a boron removal tower including an accommodation space through which water to be processed passes and a boron adsorption resin filling the accommodation space of the boron removal tower, and the boron removal tower including a plurality of sample ports through which a plurality of sample waters to be processed passing through portions having different heights of the boron adsorption resin, are respectively discharged, and determining a replacement cycle of the boron adsorption resin by increasing a passing flow rate of the boron removal tower.

A method of reducing a concentration of hydrogen peroxide from wastewater includes diluting the wastewater with water having a lower concentration of hydrogen peroxide than the wastewater to produce a diluted wastewater, contacting the diluted wastewater with a dissolved iron compound at an acidic pH to form a partially treated wastewater having a lower concentration of hydrogen peroxide than the diluted wastewater, and precipitating iron solids from the partially treated wastewater by raising a pH of the partially treated wastewater to form a neutralized partially treated wastewater.

A diluted chemical liquid production apparatus has a structure that has a platinum group metal carrying resin column, a membrane-type deaeration apparatus and a gas dissolving membrane apparatus, which are sequentially provided in a supply line of ultrapure water; and has a pH adjuster injection device and an oxidation-reduction potential adjuster injection device, which are provided between the platinum group metal carrying resin column and the membrane-type deaeration apparatus. An inert gas source is connected to a gaseous phase side of the membrane-type deaeration apparatus, and an inert gas source is also connected to the gaseous phase side of the gas dissolving membrane apparatus; and a discharge line communicates with the gas dissolving membrane apparatus. A pH meter and an ORP meter are provided in the discharge line. Such a diluted chemical liquid production apparatus can control a pH and an oxidation-reduction potential.

A heavy metal capture composition, devices including the composition, and a method of reducing heavy metal contamination in the environment is described.

A cleaning water supply device includes an ultrapure water line through which ultrapure water flows by a fixed amount, a production unit that produces cleaning water by adding a solute to the ultrapure water line by a fixed amount, a cleaning water line for causing the cleaning water to flow, cleaning machines to which the cleaning water is supplied from the cleaning water line, a solute removal unit into which excess cleaning water is introduced from the cleaning water line, and a collecting line for returning collected water from which the solute is removed to a tank and the like.

A waste liquid treating apparatus includes a waste liquid accommodating unit for waste water discharged from a processing apparatus. A waste liquid filter unit filters the waste liquid in that tank to purify the waste liquid into fresh water. A fresh water reservoir tank reserves the fresh water obtained by filtering the waste liquid by the waste liquid filter unit. A pure water producing unit purifies the fresh water reserved in the fresh water reservoir tank into pure water, and a temperature control unit controls the pure water obtained by purifying the fresh water by the pure water purifying unit to a predetermined temperature. A bubble water seal type pump sucks at least bubbles generated in the waste liquid filter unit, and a sealing water reservoir tank reserves the bubbles sucked by the bubble water seal type pump as a waste liquid.

A semiconductor process wastewater treatment system and a semiconductor process wastewater treatment method using the same are disclosed. The disclosed semiconductor process wastewater treatment system may comprises: a processing unit configured to receive semiconductor process wastewater and treats the semiconductor process wastewater through a plurality of operations; and a membrane filtration tank arranged separately from the processing unit, the membrane filtration tank having a ceramic nano-membrane for filtering the semiconductor process wastewater which has passed through the processing unit, wherein the ceramic nano-membrane may include a carbon-based nano-material. The ceramic nano-membrane may include a graphene-based nano-material as the carbon-based nano-material.