The disclosure pertains to sanitizing the permeate flow path of a reverse osmosis system. A method of sanitizing a filtration system is disclosed that can include injecting a biocide into a permeate compartment of an operating reverse osmosis system. The method can also include maintaining pressure in a concentrate compartment of the reverse osmosis system simultaneously while injecting the biocide.

A high-performance thin-film composite polyamide membrane upcycled from a substrate fouled with a biopolymer and a preparation method thereof are provided. The method includes fouling the substrate preferably with the biopolymer to obtain a composite of the substrate and a biopolymer foulant layer; then immersing the composite into a first solution formed by dissolving a polyamine monomer in water, followed by taking the composite out of the first solution and removing excess droplets from a surface of the composite; then immersing the composite treated in the previous step into a second solution formed by dissolving an acyl chloride monomer in n-hexane for interfacial polymerization to form a rejection layer on the surface of the composite; and after completion of the reaction, taking the composite out of the second solution, followed by drying and heat treatment, to obtain the target polyamide membrane.

A water desalination system includes a first set of ultrafiltration membranes, a second set of ultrafiltration membranes, a first backwashing system configured to treat at least one of the first set of ultrafiltration membranes or the second set of ultrafiltration membranes with brine generated by a reverse osmosis process, and a second backwashing system configured to treat at least one of the first set of ultrafiltration membranes or the second set of ultrafiltration membranes with one or more chemicals and reverse osmosis permeate water.

Process steps for monitoring the performance of a wastewater treatment system having a series of filtration units and optionally one or more disinfection units, controlling the operation of the filtration units, and controlling the operation of one or more maintenance operations that can be performed on the filtration units as a result of the monitoring. The wastewater treatment system can be operated without breaking pressure between the filtration units. Monitoring the performance of the wastewater treatment system can include using the water quality at various points in the system as an indicator of clogging or integrity issues within the filtration units. Sensors can be configured to measure properties of wastewater both upstream and downstream of each filtration unit, and the measured properties can be used to determine whether the filtration unit is performing adequately.

A novel multi-stage reverse osmosis system is proposed that allows for following benefits a) reduction in pressure-loss while achieving optimum cross-flow velocities and therefore reducing energy consumption of 4-10%; b) increased flux balance between stages resulting in reduced fouling of the first stage; c) disruption of scale forming conditions resulting in reduced scaling of the last stage; d) reduction in scale potential of the concentrate valve; e) reduction in downtime for CIP by proactively disrupting scaling or fouling through several innovative methods; f) ease-of and effectiveness-of CIP with reduced number of valves and g) to keep system operational via isolation of the last stage for maintenance while the keeping remaining system in production mode. All the above improvements are achieved with process-flow and operational characteristics defined in the Specifications and Claims.

A filtration apparatus for treating a fluid comprises a vessel, a first partition plate dividing the vessel into first and second chambers and defining a through hole, and a filtration module located within the second chamber and including a body section defining an outer diameter which is greater than the diameter of the through hole in the first partition plate. The apparatus further comprises a reducing connector having a first end secured to the body section of the filtration module and a second end sealed relative to the through hole in the first partition plate to permit communication between the filtration module and the first chamber.

In a disclosed embodiment the apparatus includes a second partition plate such that the vessel is divided into first, second and third chambers, wherein the filtration module is mounted between the partition plates.

A filtering device is for obtaining a chemical liquid by purifying a liquid to be purified and has an inlet portion, an outlet portion, a filter A, a filter B different from the filter A, and a flow path extending from the inlet portion to the outlet portion, in which the filter A and the filter B are arranged in series between the inlet portion and the outlet portion and have, and the filter A is selected from the group consisting of predetermined filters A1, A2, and A3.

A water desalination system includes a first set of ultrafiltration membranes, a second set of ultrafiltration membranes, a first backwashing system configured to treat at least one of the first set of ultrafiltration membranes or the second set of ultrafiltration membranes with brine generated by a reverse osmosis process, and a second backwashing system configured to treat at least one of the first set of ultrafiltration membranes or the second set of ultrafiltration membranes with one or more chemicals and reverse osmosis permeate water.

The water treatment device according to the present disclosure includes: an electrochemical cell having electrodes including a positive electrode and a negative electrode, and a bipolar membrane; a tank; a power supply configured to apply power to the electrodes; a water circulation flow path having at least the tank and the electrochemical cell and through which water circulates; a circulation device configured to circulate water in the water circulation flow path; a raw water supply path configured to supply raw water to the water circulation flow path; and a control device. In performing water softening treatment in the electrochemical cell where power is applied to the electrodes so as to remove ions from raw water and soft water is produced, the control device drives the circulation device so as to circulate water in the water circulation flow path.

A composition for cleaning membranes used in food processing comprising an amine oxide and an alkyl sulfate, the composition maintaining good cleaning performance whilst leaving a low residue of surfactant on the membrane that is cleaned using the composition. A method of use of the composition is also presented.