Abstract: The present invention relates to a water treatment method including: a filtration step of feeding water to be treated to a membrane filtration device having loaded therein a porous separation membrane and performing filtration treatment to obtain filtrate; a discharging step of discharging the water to be treated in the membrane filtration device, which has been separated and concentrated by the porous separation membrane; and a cleaning step of cleaning the porous separation membrane by at least one treatment of physical cleaning and chemical cleaning, in which a cycle including a combination of the filtration step, the discharging step and the cleaning step is repeated multiple times, thereby obtaining filtrate. In each cycle, the filtration step and the discharging step are repeated multiple times, and the cleaning step is then carried out.

Abstract: A cooling medium circulating apparatus comprising a first flow path configured to circulate a cooling medium, a second flow path through configured to circulate the cooling medium, and a flow path switchover unit configured to connect or disconnect between the first flow path and the second flow path, wherein a prescribed cycle, a connecting period and a disconnecting period is set, the connecting period being a connecting period between the first flow path and the second flow path in the said prescribed cycle, the disconnecting period being a disconnecting period between the first flow path and the second flow path in the said prescribed cycle, whereby the flow path switchover unit is controlled on the basis of the connecting period and the disconnecting period, and the prescribed cycle is made shorter as a temperature difference between a temperature of the cooling medium flowing through the first flow path and a temperature of the cooling medium flowing through the second flow path is larger.

Abstract: Provided is a water treatment method in which impurities such as suspended substances in raw water are efficiently removed using a separation membrane, and in particular clarified water with sufficiently high water quality is stably produced as supplied water of a reverse osmosis membrane unit using a microfiltration membrane or an ultrafiltration membrane. The water treatment method, includes dosing a cationic coagulant to raw water a to form primary coagulated water, using the primary coagulated water as it is as final coagulated water when the zeta potential of the primary coagulated water b is less than 0 mV, or using final coagulated water obtained by dosing an anionic substance so that the zeta potential is less than 0 mV when the zeta potential of the primary coagulated water b is 0 mV or more, and treating the final coagulated water with a separation membrane of which the surface zeta potential is less than 0 mV, to obtain treated water d.

Abstract: A fresh water producing apparatus for producing fresh water from raw water containing solutes is disclosed. The fresh water producing apparatus comprises a first semipermeable membrane unit and a second semipermeable membrane unit. A first raw water supply line for supplying the raw water is connected to the first semipermeable membrane unit. A second raw water supply line for supplying the raw water is connected to the second semipermeable membrane unit. The first semipermeable membrane unit and the second semipermeable membrane unit are connected by a concentrated water line for supplying concentrated water of the first semipermeable membrane unit to the second semipermeable membrane unit.

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: The present invention relates to a separation membrane module in which a plurality of spiral-type separation membrane elements for use in separating and removing ingredients present in a fluid to be treated are loaded. The present invention provides a separation membrane module in which a plurality of spiral-type separation membrane elements are loaded in a cylindrical pressure-resistant vessel and which allows easy loading and removal of the separation membrane elements while maintaining sealing property even when high-hardness foreign particles are present on sealing surfaces and fully achieving its performance, thereby ensuring reductions in maintenance time and labor, and provides a replacement method for such separation membrane elements.

Abstract: A concentration-difference power generation apparatus in which high-concentration water and low-concentration water which differ in their concentrations are brought into contact with each other through a semi-permeable membrane unit including a semi-permeable membrane, and a resultant increase in an amount of the high-concentration water due to permeation of water from a low-concentration side to a high-concentration side caused by a forward osmotic pressure is utilized to drive an electric generator to generate electricity, in which the semi-permeable membrane unit is divided into a plurality of subunits and the concentration-difference power generation apparatus includes a pressure change mechanism disposed on a high-concentration-side channel extending from the preceding-stage subunit to the next-stage subunit or a low-concentration-side channel.

Abstract: A recording sheet has an unfixed toner image that is formed thereon, and is conveyed to a fixing device. A surface reforming device of the fixing device performs surface reformation for the surface of the toner on the recording sheet by, for example, plasma irradiation or the like, thereby generating a polar group of a hydrophilic property on the surface of the toner. Next, the recording sheet is conveyed to a laser irradiation portion by a recording sheet conveyance device to be irradiated with a laser, in which the toner is fused to be fixed to the recording sheet. The toner on the recording sheet is subjected to surface reforming treatment, thus having increased affinity (adhesion force) with the recording sheet, so that it is possible to secure favorable fixability without pressing.

Abstract: To provide an image forming apparatus in which multiple number of laser beams are controlled to perform fixing based on the toner concentration in the developing device, or based on the density and weight of the toner image adhering on the recording medium before fixing. The controller in the image forming apparatus compares the toner concentration detected by the toner concentration detector with the reference toner concentration, calculates the output level of the laser irradiator, controls the laser irradiator based on the calculation, controls to increase the output level of the laser irradiator in accordance with the detected toner concentration when the toner concentration is lower than the reference toner concentration, and controls to lower the output level of the laser irradiator in accordance with the detected toner concentration when the toner concentration is higher than the reference toner concentration.

Abstract: A laser fusing apparatus including: a laser light source for emitting a laser beam; a conveyance belt for conveying a sheet with a toner image being transferred thereon and guiding the sheet to an irradiation region in which the toner image is to be irradiated with the laser light source; a heat pipe including a heat receiving portion to receive heat generated by the laser light source and a heat releasing portion to supply the received heat to the conveyance belt; and a fuser control section for controlling the laser light source so that the laser light source irradiates the laser beam to the toner image when the toner image passes the irradiation region, thereby fixing the toner image onto the sheet, wherein the conveyance belt heats the sheet and the toner image with the heat supplied from the heat radiation section.

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.

Abstract: An optical fixing device is provided that is capable of improving fixability as well as improving smoothness of an image on a recording medium that is formed after fixing, and forming a high-quality image of high gloss level. An optical fixing device includes a recording sheet fixing conveyance section that conveys a recording sheet on which a toner image is formed; a laser irradiation section that irradiates with light the toner image formed on the recording sheet that is conveyed by the recording sheet fixing conveyance section; and a pressurizing section that is disposed on a downstream side in a conveyance direction of the recording sheet from the light irradiation section and pressurizes the toner image on the recording sheet after irradiation of light by the light irradiation section.

Abstract: In a method for cleaning a membrane module including at least one of a microfiltration membrane and an ultrafiltration membrane through which raw water is membrane-filtered to obtain membrane filtrate, a chemical diffusion step is provided in which chemical-containing water is fed to a feed side of the membrane module and diffused from the feed side of the membrane module to a filtrated side of the membrane module is performed, and subsequently a backwashing step is provided in which the membrane module is backwashed by allowing the membrane filtrate to flow from the filtrated side to the feed side of the membrane module is performed, in which, in the chemical diffusion step, an execution time of the chemical diffusion step is controlled based on a concentration of the chemical diffused to the filtrated side of the membrane module.

Abstract: A fixing device includes a laser light source for irradiating an unfixed toner image formed on a recording sheet, and melts a toner by light from the laser light source to fix the toner image on the recording sheet. Here, where a conveyance speed of the recording sheet is p, a length of a light irradiation area in a conveyance direction of the recording sheet is q, time during which the toner of the unfixed image is subjected to light during conveyance is r, and energy per unit area given to the toner of the unfixed image is J, light output of the laser light source is controlled so that the energy during a constant time r1 from the start of a time r is differentiated from the energy during a time r2 until the end of the time r after the elapse of the r1.

Abstract: In order to prevent oxidation degradation of a semipermeable membrane and biofouling growth and avoid an increase in cost due to chemicals and the like, the present invention provides a fresh water production method including membrane-filtering raw water with a microfiltration/ultrafiltration membrane module, followed by performing membrane filtration with a semipermeable membrane unit, in which the membrane filtration in the microfiltration/ultrafiltration membrane module is temporarily interrupted, chlorine agent-containing water is fed from a secondary side of the microfiltration/ultrafiltration membrane module to perform back-pressure washing of the microfiltration/ultrafiltration membrane module, thereafter, an ammoniacal compound and/or an amino group-containing compound are added to a primary side of the microfiltration/ultrafiltration membrane module, and the membrane filtration in the microfiltration/ultrafiltration membrane module is resumed.

Abstract: In a fixing device, the surface of the recording paper carrying belt passes through a position satisfying a relation: f<L?f+a, where L is a distance (mm) from the center of a condensing lens 112 to the position along the optical axial direction, the condensing lens 112 being the last condensing lens that laser light irradiated from a laser light source passes through, f is a focal distance (mm) of the condensing lens 112, and a is a range (mm) along the optical axial direction from the focal position of the condensing lens 112 to a position, within which range fixability of toner is within a set permissible range.

Abstract: A fresh water producing apparatus for producing fresh water from raw water containing solutes is disclosed. The fresh water producing apparatus comprises a first semipermeable membrane unit and a second semipermeable membrane unit. A first raw water supply line for supplying the raw water is connected to the first semipermeable membrane unit. A second raw water supply line for supplying the raw water is connected to the second semipermeable membrane unit. The first semipermeable membrane unit and the second semipermeable membrane unit are connected by a concentrated water line for supplying concentrated water of the first semipermeable membrane unit to the second semipermeable membrane unit.

Abstract: A color toner for optical fixing containing an infrared light absorbent and being compatible with an optical fusing device to irradiate an unfixed toner attached on a surface of a recording medium with infrared light to melt and fix the unfixed toner on the recording medium, wherein an optical absorptance of the color toner is set to be lower than an optical absorptance of a black toner in a wavelength region of the infrared light emitted from the optical fusing device.

Abstract: A method is provided for producing fresh water, the method including feeding raw water to a semipermeable membrane to obtain fresh water, in which water having a solute concentration different from that of the raw water is fed and mixed with the raw water according to changes of a flow rate of fresh water of the semipermeable membrane unit and/or operating pressure of the semipermeable membrane unit.