Abstract: The present invention relates to a method of controlling a fresh-water production apparatus for treating a raw water in stages by N-stage (N is a natural number of 2 or larger) water treatment methods, the method including: a filtration-characteristic prediction step; a filtration-characteristic deviation assessment step; a filtration-characteristic deviation assessment step; a cyclic prediction calculation step; a control condition recording step; a cyclic prediction calculation step; and a control condition recording step, in which the fresh-water production apparatus is controlled on the basis of the control condition recording step for the (n?1)-th stage water treatment method and the control condition recording step for the n-th stage water treatment method.

Abstract: The present invention provides a fresh water generator operating method and a determination program that are employed in a method for cleaning a separation membrane module following membrane filtration, and that, while various cleaning steps such as reverse pressure cleaning, air cleaning, chemical solution cleaning are taking place after completion of the membrane filtration, determines cleaning troubles by calculating a temporal change in resistance increase rate on the basis of an increase in membrane differential pressure.

Abstract: Provided is an effluent treatment method based on a membrane separation activated sludge method, the effluent treatment method being characterized in that activated sludge collected from a membrane separation activated sludge tank is observed by an optical means, image processing is performed, and effluent treatment conditions are controlled in accordance with the results thereof.

Abstract: The present invention provides a method for preparing a water quality profile that has (1) a step 1 for supplying water to be treated to a separation membrane module with a supply port for the water being treated and multiple permeate outlets and obtaining permeate, (2) a step 2 for varying the ratio of the flow rates of the respective permeates flowing out of the multiple permeate outlets, (3) a step 3 after step 2 for measuring the respective water qualities of the permeates, and (4) a step 4 for plotting the relationship between the ratio of the respective permeate flow rates varied in step 2 and the respective water qualities of the permeates measured in step 3 as a scatter diagram, steps 2-4 being repeated multiple times.

Abstract: The present invention relates to a computer-readable recording medium having recorded thereon a clogging location determination program for a separation membrane module, in which, in order to determine a clogging location of a separation membrane module in a fresh water generation system for obtaining treated water by filtrating water to be treated by a separation membrane module having a separation membrane, a computer is caused to function as a clogging location determination means for determining a clogging location of the separation membrane module from a resistance in a lower part of the separation membrane module, a filtration resistance of a hollow-fiber membrane, and a resistance in an upper part of the separation membrane module.

Abstract: The present invention relates to a computer-readable recording medium having recorded thereon a clogging location determination program for a separation membrane module, in which, in order to determine a clogging location of a separation membrane module in a fresh water generation system for obtaining treated water by filtrating water to be treated by a separation membrane module having a separation membrane, a computer is caused to function as a clogging location determination means for determining a clogging location of the separation membrane module from a resistance in a lower part of the separation membrane module, a filtration resistance of a hollow-fiber membrane, and a resistance in an upper part of the separation membrane module.

Abstract: Provided is an effluent treatment method based on a membrane separation activated sludge method, the effluent treatment method being characterized in that activated sludge collected from a membrane separation activated sludge tank is observed by an optical means, image processing is performed, and effluent treatment conditions are controlled in accordance with the results thereof.

Abstract: According to the present invention, since a pretreatment mechanism can be operated while inhibiting the pretreated water from fluctuating in pressure, a fresh-water production apparatus is obtained in which the desalting mechanism can be stably operated. Furthermore, the period of water supply or flushing in the step of washing the pretreatment mechanism can be shortened, and the load on the lines where washing is not being performed is hence reduced. Consequently, a fresh-water production apparatus is obtained in which the pretreatment mechanism can be operated while inhibiting the pretreatment membranes from being fouled.

Abstract: The present invention relates to a computer-readable recording medium having recorded thereon a clogging location determination program for a separation membrane module, in which, in order to determine a clogging location of a separation membrane module in a fresh water generation system for obtaining treated water by filtrating water to be treated by a separation membrane module having a separation membrane, a computer is caused to function as a clogging location determination means for determining a clogging location of the separation membrane module from a resistance in a lower part of the separation membrane module, a filtration resistance of a hollow-fiber membrane, and a resistance in an upper part of the separation membrane module.

Abstract: According to the present invention, since a pretreatment mechanism can be operated while inhibiting the pretreated water from fluctuating in pressure, a fresh-water production apparatus is obtained in which the desalting mechanism can be stably operated. Furthermore, the period of water supply or flushing in the step of washing the pretreatment mechanism can be shortened, and the load on the lines where washing is not being performed is hence reduced. Consequently, a fresh-water production apparatus is obtained in which the pretreatment mechanism can be operated while inhibiting the pretreatment membranes from being fouled.

Abstract: A membrane separation device includes a separation membrane unit A that has a separation membrane unit component 8, feed stream side lines F1 and F2, and a permeate stream line P, and a unit for feeding a stream-to-be-treated, wherein a stream-to-be-treated sealing material is provided in the perimeter of an anti-telescoping plate of the separation membrane element, wherein the separation membrane elements can be moved within a cylindrical pressure vessel substantially in either direction, wherein the separation membrane unit is configured to feed the stream-to-be-treated through one of the feed stream side lines F1 and F2 and to discharge the concentrate stream through the other of the feed stream side lines, and wherein the separation membrane unit includes a mechanism that can switch the flow between the feed stream side lines.

Abstract: A membrane separation device includes a separation membrane unit A that has a separation membrane unit component 8, feed stream side lines F1 and F2, and a permeate stream line P, and a unit for feeding a stream-to-be-treated, wherein a stream-to-be-treated sealing material is provided in the perimeter of an anti-telescoping plate of the separation membrane element, wherein the separation membrane elements can be moved within a cylindrical pressure vessel substantially in either direction, wherein the separation membrane unit is configured to feed the stream-to-be-treated through one of the feed stream side lines F1 and F2 and to discharge the concentrate stream through the other of the feed stream side lines, and wherein the separation membrane unit includes a mechanism that can switch the flow between the feed stream side lines.

Abstract: There is provided a separation membrane unit wherein a plurality of separation membrane subunits (11a-c) communicate with raw water lines A (9a-c) that comprise raw water supply valves W (10a-c), water discharge lines B (12a-c) that comprise water discharge valves X (13a-c), raw water lines C (16a-c) that comprise first raw water communication valves Y (17a-c), raw water lines D (19a-c) that comprise second raw water communication valves Z (20a-c), and permeate water lines E (21a-c); and wherein the raw water lines A communicate with the water discharge lines B, the raw water lines C communicate with the raw water lines D, the raw water lines A communicate with a main raw water line 7, the water discharge lines B communicate with a main water discharge line 14, the raw water lines C and the raw water lines D communicate with a collection line 18, and the permeate water lines E communicate with a main permeate water line 22.

Abstract: A membrane filtration method and membrane filtration device including a pre-treatment membrane module that filters raw water with a filtration membrane and obtains pre-treated water; a reverse osmosis membrane module that filters the pre-treated water obtained from the pre-treatment membrane module with a reverse osmosis membrane and obtains permeate and retentate; a communicating tube channel that directly joins the pre-treated water outlet of the pre-treatment membrane module and the pre-treated water inlet of the reverse osmosis membrane module; and a branch tube channel that branches from the communicating tube channel and diverts a portion of the pre-treated water flowing in the communicating tube channel from the communicating tube channel. The filtration membrane of the pre-treatment membrane module is backwashed using the pre-treated water that has been diverted by the branch tube channel.