Abstract: An electrodialysis apparatus includes an anode chamber (10) having an anode (2), and a cathode chamber (50) having a cathode (3). The electrodialysis apparatus includes a desalting chamber (40) for removing fluoride ions from waste water supplied to produce treated water, a concentrating chamber (30) for concentrating the fluoride ions, which have moved from the desalting chamber (40), in the waste water to produce concentrated water, and a buffer chamber (20) for blocking the fluoride ions in the waste water from flowing from the concentrating chamber (30) directly into the anode chamber (10). The electrodialysis apparatus also include a path for supplying pure water to the anode chamber (10), and a path for supplying effluent water from the anode chamber (10) to the buffer chamber (20).

Abstract: A liquid treatment apparatus includes a cathode chamber (4) having a cathode (7), an anode chamber (1) having an anode (6), a deionization chamber (2) disposed between the cathode chamber (4) and the anode chamber (1), and a neutralization chamber (3) disposed between the cathode chamber (4) and the anode chamber (1). The deionization chamber is configured to selectively remove cations or anions from a water to be treated and receive ions having the same charge as the selectively removed ions from the cathode chamber (4) or the anode chamber (1). The neutralization chamber is configured to receive the removed ions and electrically neutralize the removed ions by ions supplied from the anode chamber (1) or the cathode chamber (4). An ion exchange membrane is provided to partition the deionization chamber and the neutralization chamber.

Abstract: In a small scaled plant intended for flexible manufacturing, a pure water supply system is provided at a low cost without reducing a production efficiency. A pure water system produces a plurality of grades of pure water which are supplied through pipes connected to points of use for cleaning, CMP, lithography, and the like. Upon receipt of a request signal from each point of use for starting to use a certain grade of pure water, a controller determines whether or not a required amount exceeds the capacity of the grade of pure water which can be supplied by the pure water system. If not, the controller sends a use permission signal to the point of use for permitting the same to use the pure water. When a certain use point is using the requested grade of pure water, the controller may not permit the requesting point of use to use the pure water until a use end signal is sent from the use point which is using the pure water.

Abstract: The present invention provides an electrolytic deposition treatment apparatus and method which can reduce metal ion concentration of waste water to be treated by electrolytic deposition to the degree to which treated water can be discharged to the outside, and which can treat waste water, even if the quantity of waste water produced in a semiconductor device fabrication apparatus is large. The electrolytic deposition treatment apparatus comprises a cathode(3) for depositing metal ions in water to be treated as metal, a cation exchange membrane(4) disposed so as to face the cathode(3), and an anode(6) disposed so as to face the cation exchange membrane(4) through a cation exchanger(5). The water to be treated is supplied to a space between the cathode(3) and the cation exchange membrane(4).

Abstract: A bipolar chamber is used in an electrochemical liquid treatment apparatus such as an electrodialyzer and an electrolyzer. The bipolar chamber includes an anion-exchange membrane (1), an electrode (2), and a cation-exchange membrane (3). A liquid is supplied between the cation-exchange membrane (3) and the anion-exchange membrane (1). The anion-exchange membrane (1), the electrode (2), and the cation-exchange membrane (3) are arranged in this order from an anode side of the bipolar chamber. The liquid may include pure water or a nonelectrolyte aqueous solution.

Abstract: The present invention aims to provide electrode compartment structures in electrochemical liquid treatment equipments, which enable stable operation using pure water as an electrode compartment liquid requiring no concentration adjustment without adverse electrode reaction. The present invention relates an electrochemical liquid treatment equipment comprising ion exchange membranes between an anode and a cathode, which has an anode compartment defined by the anode and a cation exchange membrane and a cathode compartment defined by the cathode and an anion exchange membrane (12), each of the anode compartment and cathode compartment being packed with an ion exchanger (14) composed of a fibrous a material, each of the anode and cathode (11) being formed from a liquid- and gas-permeable and electrically conductive material, and the equipment also having an electrode compartment liquid flowing chamber (15) which is formed behind each of the anode and cathode.

Abstract: The present invention relates to a method and apparatus for removing and recovering metal such as copper from various kinds of waste water containing copper. A method for treating waste water includes treating waste water in a copper treatment step (10) comprising a combination of electrodialysis operation and electrolytic deposition operation to produce treated water (107) having a lowered copper concentration, and recovering copper from the waste water.

Abstract: The present invention relates to a method for removing and recovering metal ions from various kinds of waste water to be treated. The method comprises an oxidizing agent removing apparatus for decomposing and removing an oxidizing agent from the water, and an electrolytic deposition apparatus (21) for removing and recovering metal ions from the water discharged from the oxidizing agent removing apparatus. The electrolytic deposition apparatus has electrodes and an ion exchanger disposed between the electrodes.

Abstract: In a small scaled plant intended for flexible manufacturing, a pure water supply system is provided at a low cost without reducing a production efficiency. A pure water system produces a plurality of grades of pure water which are supplied through pipes connected to points of use for cleaning, CMP, lithography, and the like. Upon receipt of a request signal from each point of use for starting to use a certain grade of pure water, a controller determines whether or not a required amount exceeds the capacity of the grade of pure water which can be supplied by the pure water system. If not, the controller sends a use permission signal to the point of use for permitting the same to use the pure water. When a certain use point is using the requested grade of pure water, the controller may not permit the requesting point of use to use the pure water until a use end signal is sent from the use point which is using the pure water.

Abstract: An electrolytic solution control method can control the composition of an electrolytic solution efficiently with high precision, and can remove a partially decomposed product of an organic component from an electrolytic solution. The electrolytic solution control method includes storing an electrolytic solution containing an organic component and an inorganic component in an electrolytic solution storage tank while controlling and keeping the electrolytic solution at a predetermined composition, adjusting an inorganic component of the waste electrolytic solution after use in electrolytic processing in an electrolytic processing apparatus, and then returning the waste electrolytic solution to the electrolytic solution storage tank.

Abstract: An electromagnetic wave applying apparatus having an electromagnetic wave source (13) such as an ultraviolet lamp or the like, a cylinder (15) surrounding the electromagnetic wave source, a liquid retention tank (16) disposed around the cylinder, and an inlet portion (17) for introducing a liquid overflow from the liquid retention tank as a thin film flowing down an inner wall surface of the cylinder, which is irradiated with an electromagnetic wave from the ultraviolet lamp (11). The electromagnetic wave applying apparatus also has swirling flow forming means for causing the liquid introduced from the inlet portion (17) onto the inner wall surface of the cylinder to flow as a swirling flow down the inner wall surface. The electromagnetic wave applying apparatus allows a large amount of liquid to be stably treated by the application of an electromagnetic wave without causing the electromagnetic wave source such as an ultraviolet lamp or the like to be contaminated.

Abstract: An electromagnetic wave applying apparatus according to the present invention has an electromagnetic wave source (13) such as an ultraviolet lamp or the like, a cylinder (15) surrounding the electromagnetic wave source, a liquid retention tank (16) disposed around the cylinder, and an inlet portion (17) for introducing a liquid overflow from the liquid retention tank as a thin film flowing down an inner wall surface of the cylinder, which is irradiated with an electromagnetic wave from the ultraviolet lamp (11). The electromagnetic wave applying apparatus also has swirling flow forming means for causing the liquid introduced from the inlet portion (17) onto the inner wall surface of the cylinder to flow as a swirling flow down the inner wall surface. The electromagnetic wave applying apparatus allows a large amount of liquid to be stably treated by the application of an electromagnetic wave without causing the electromagnetic wave source such as an ultraviolet lamp or the like to be contaminated.

Abstract: A method for treating liquid-waste utilizing carriers having microorganisms immobilized thereon employs an aerobic treatment tank. At least one underwater agitation type aeration apparatus having an air-diffusing mechanism on a discharge side of an impeller is provided in the treatment tank. While supplying atomized air into the liquid-waste, the carriers and the liquid-waste are circulated through the treatment tank by the underwater agitation type aeration apparatus, to thereby substantially uniformly distribute the carriers in a floating state in the treatment tank. The discharge opening of the underwater agitation type aeration apparatus is provided in the vicinity of a bottom surface of the treatment tank or at an intermediate position with respect to the depth of liquid in the treatment tank.