Abstract: The water treatment apparatus of the present invention comprises a flocculation part into which water to be treated is introduced, at least two flocculant adding devices installed so that different flocculants can be added to the flocculation part, one or two or more water quality measurement devices for measuring the quality of the water to be treated, and a controlling part for issuing, on the basis of the measurement result from the water quality measurement device(s), a command relating to whether addition of the flocculants to the corresponding flocculant adding device is required or not and to the added amounts of the flocculants, wherein at least one of the flocculant adding devices is an auxiliary flocculant adding device.

Abstract: A hollow fiber membrane filtration device includes a hollow fiber membrane module including a vessel having a treated water outlet and a concentrated water outlet; a plurality of hollow fiber membranes each of which separates raw water into permeated water and concentrated water, and is vertically disposed in the vessel; an upper end fixing member that fixes upper end parts of the hollow fiber membranes and is disposed at an upper part in the vessel; a permeated water chamber that is formed on an upper side of the upper end fixing member and communicates with an interior of each of the hollow fiber membranes; and a water conduit through which the raw water is supplied into the vessel. The water conduit vertically extends on a lower side of the upper end fixing member, and a plurality of ejection holes is provided on a side peripheral surface to eject raw water.

Abstract: A hollow fiber membrane filtration device includes a hollow fiber membrane module including a vessel that includes a treated water outlet and a concentrated water outlet, hollow fiber membranes, an upper end fixing member that fixes upper end parts of the hollow fiber membranes, a permeated water chamber that is formed on an upper side of the upper end fixing member, a water conduit through which raw water is supplied into the vessel, and a diffusion tube that is provided on a lower side of the hollow fiber membranes. A plurality of ejection holes are provided on a side peripheral surface of the water conduit. A raw water pipe and gas introduction device are connected with the water conduit. A drainage port is provided at a lower part of the vessel.

Abstract: Provided are a method and an apparatus for clarifying industrial water that enable industrial water to be clarified to a high degree with a small amount of coagulant instead of an inorganic coagulant, such as PAC, aluminum sulfate, or ferric chloride, which need to be used in a large amount for clarifying industrial water and are capable of producing treated water having qualities particularly suitable for an RO membrane treatment. The method for clarifying industrial water includes adding a melamine-formaldehyde resin acid colloidal solution to industrial water in order to coagulate the industrial water and subsequently filtering the coagulated water. The coagulated water may be directly filtered with a pressure or gravity filtration device, or with a microfiltration or ultrafiltration membrane module, without being subjected to solid-liquid separation using a sedimentation or floatation separation device prior to the filtration treatment.

Abstract: There is provided a water treatment method using a water treatment flocculant that suffers from minimal secondary contamination with flocculation residues and contains an alkaline solution of a phenolic resin. A water treatment method involving the addition of a flocculant to water to be treated and subsequent membrane separation treatment. The flocculant contains an alkaline solution of a phenolic resin having a melting point in the range of 130° C. to 220° C. The water treatment flocculant is produced by a resole-type second-order reaction in the presence of an alkaline catalyst in which an aldehyde is added to an alkali solution of a novolak phenolic resin. The novolak phenolic resin is produced by a reaction between a phenol and an aldehyde in the presence of an acid catalyst.

Abstract: A filtration apparatus 10, includes: a filter body 4 formed by spirally winding a sheet-shaped member; and a filtration tank 1 through which water to be treated is passed, and into which the filter body 4 is charged such that the axis of the filter body 4 extends along the direction of water passage, wherein the sheet-shaped member is composed of a sheet-shaped mesh sheet 5 having holes through which the water to be treated passes, and a sheet-shaped spacer 6 through which the water to be treated passes with difficulty as compared with the mesh sheet 5, the sheet surfaces of the mesh sheet 5 and the spacer 6 being superposed on each other.

Abstract: There is provided a water treatment method using a water treatment flocculant that suffers from minimal secondary contamination with flocculation residues and contains an alkaline solution of a phenolic resin. A water treatment method involving the addition of a flocculant to water to be treated and subsequent membrane separation treatment. The flocculant contains an alkaline solution of a phenolic resin having a melting point in the range of 130° C. to 220° C. The water treatment flocculant is produced by a resole-type second-order reaction in the presence of an alkaline catalyst in which an aldehyde is added to an alkali solution of a novolak phenolic resin. The novolak phenolic resin is produced by a reaction between a phenol and an aldehyde in the presence of an acid catalyst.

Abstract: The filtration apparatus of the invention includes a filtration member 12 which has a ribbon-like suspended-solid-capturing member for capturing suspended solid present in fed treatment water 1, wherein the filtration member is charged in a filtration tank 11 such that a filtration portion of the filtration tank has a percent void of 50 to 95% during passage of the treatment water.

Abstract: To provide a membrane separation method capable of attaining reduced adsorption of a membrane-fouling substance contained in treatment water onto the surface of a separation membrane during membrane separation of the treatment water, to thereby lead retarded deterioration in membrane separation performance, and a membrane separation apparatus for performing the method. In the membrane separation method, to treatment water, a particulate cationic polymer which swells in water but does not substantially dissolve therein is added, and the treatment water is subjected to membrane separation.