JP2011083764A5 - - Google Patents

Description

That is, the present invention is a water purification system that uses a membrane module, pressurizes water with a water supply pump, and supplies the membrane module with membrane filtration to perform membrane filtration. Membrane filtration that generates ultrafine bubbles in the water after pressurization and before the supply of the membrane module, supplies the permeated water containing the ultrafine bubbles to the membrane module, and obtains permeate containing the ultrafine bubbles There is provided a method for operating a water purification system comprising a step and a backwashing step of intermittently backwashing with permeated water from the membrane module .

The present invention is also a water filtration method including a step of pressurizing water with a water supply pump, supplying the pressure to a membrane module or a filter and performing filtration to obtain permeated water or filtered water, the water supply pump The ultrafine bubbles are generated in the water after the pressurization at the time and before the supply of the membrane module or the filter, the liquid containing the ultrafine bubbles is supplied to the membrane module or the filter and filtered, and the ultrafine bubbles are removed. There is provided a water filtration method comprising a filtration step of obtaining permeated water or filtered water contained therein, and a backwashing step of intermittent backwashing with permeated water from the membrane module or filter.

Claims (14)

In a water purification system using a membrane module, an operation method of a water purification system in which water is pressurized by a water supply pump, and supplied to the membrane module to perform membrane filtration, after being pressurized by the water supply pump. A membrane filtration step for generating ultrafine bubbles in water before supplying the membrane module, supplying the permeated water containing the ultrafine bubbles to the membrane module, and obtaining permeated water containing the ultrafine bubbles, and the membrane module And a backwashing step of intermittently backwashing with permeated water from the water .   The operation method of the water purification system according to claim 1, wherein the water supplied to the water supply pump is raw water and / or concentrated circulating water from a membrane module.   The water to be supplied to the water supply pump is clean water and / or permeated water from the membrane module, and a liquid containing ultrafine bubbles is used for cleaning the device or apparatus to be cleaned, and then the cleaning liquid after use. The operation method of the water purification system according to claim 1, wherein the water is supplied to the membrane module.   The gas-liquid mixed fluid formed by mixing a gas-liquid mixed fluid obtained by mixing a gas with water through a flow path having a reduced portion, a most sandwiched portion, and an enlarged portion by high pressure from a water supply pump. The operation method of the water purification system according to any one of claims 1 to 3, wherein ultra fine bubbles mainly having a size of 50 µm or less are generated by changing a flow velocity and a pressure of a high-speed shear flow of fluid.   The operation of the water purification system according to any one of claims 1 to 4, wherein a filtration pressure when performing membrane filtration with a membrane module by pressurizing water with a water supply pump is 0.01 MPa (gauge pressure) or more. Method.   The operation method of the water purification system according to any one of claims 1 to 5, wherein the membrane filtration method in the membrane module is a cross flow filtration method.   The operation method of the water purification system according to any one of claims 1 to 6, wherein the membrane module is an ultrafiltration membrane module or a microfiltration membrane module. A method of filtering water comprising the steps of pressurizing water with a water supply pump, supplying the membrane module or filter to perform filtration, and obtaining permeated water or filtered water, after pressurizing with the water supply pump Ultrafine bubbles are generated in the water before the membrane module or filter is supplied, and the liquid containing the ultrafine bubbles is supplied to the membrane module or the filter and filtered, and the permeated water or the filtration containing the ultrafine bubbles is filtered. A water filtration method comprising: a filtration step of obtaining water; and a backwashing step of intermittently backwashing with permeated water from the membrane module or filter.   In a water purification system using a membrane module, a water supply pump for supplying water to the membrane module, a gas supply means for supplying gas into the water supply line, and a gas-liquid mixed fluid obtained by mixing gas in the water The flow rate and pressure of the high-speed shear flow of the gas-liquid mixed fluid formed in the flow path are changed by circulating the flow path having the reduced part, the most sandwiched part, and the enlarged part by high pressure by the water supply pump. A water purification system comprising ultrafine bubble generating means for generating ultrafine bubbles in water.   The water purification system according to claim 9, wherein the water supplied to the water supply pump is raw water and / or concentrated circulating water from a membrane module.   The water to be supplied to the water supply pump is clean water and / or permeated water from the membrane module, and includes a device to be cleaned or a device to be cleaned with a liquid containing ultrafine bubbles therein. The water purification system according to claim 9, wherein the liquid after cleaning of the apparatus is supplied to the membrane module.   The water purification system according to any one of claims 9 to 11, wherein the gas supply means is provided immediately before the water supply pump.   Furthermore, the water purification system of any one of Claims 9-12 provided with the washing | cleaning means which backwashes a membrane module intermittently.   Furthermore, the water purification system of any one of Claim 10 with which the pre filter which removes the contaminant of raw | natural water is provided.