An online cleaning system for micro-polluted nanofiltration membranes uses forward osmosis, and a process of the online cleaning system, and relates to the field of water treatment membrane separation technique. The online cleaning system includes a nanofiltration raw water tank, a nanofiltration membrane assembly, a pure water tank, a forward osmosis feed solution tank, a forward osmosis draw solution tank, a first saline water tank, a second saline water tank and a water bath temperature control device. Compared with convention techniques, some embodiments include efficient cleaning of the nanofiltration membranes that is realized by using forward osmosis as a nanofiltration membrane cleaning system, and cyclic regeneration of the nanofiltration membranes can be realized, so that the purposes of removing dissolved organic matters in micro-polluted raw water, reducing hardness of calcium and magnesium and prolonging the service life can be achieved.

Zero liquid discharge systems, processes, and techniques for treating a saltwater without evaporative crystallization. The saltwater is treated by a fluidic circuit comprising a high-pressure reverse osmosis (“HPRO”) unit configured to operate at a hydraulic pressure of at least 1,500 psi, a cooling crystallizer, and a solids-liquid separator. The saltwater is first concentrated by the HPRO unit to produce an HPRO brine, which is subsequently cooled to a designated crystallization temperature by the cooling crystallizer. The cooling crystallizer crystallizes salt crystals from the cooled HPRO brine and produces a salt-diminished brine. The solids-liquid separator separates the salt-diminished brine from the salt crystals. The salt-diminished brine from the solids-liquid separator is returned to the HPRO unit for further treatment, which allows additional salts to be crystallized from the returned salt-diminished brine.

Zero liquid discharge systems, processes, and techniques for treating a saltwater without evaporative crystallization. The saltwater is treated by a fluidic circuit comprising a high-pressure reverse osmosis (“HPRO”) unit configured to operate at a hydraulic pressure of at least 1,500 psi, a cooling crystallizer, and a solids-liquid separator. The saltwater is first concentrated by the HPRO unit to produce an HPRO brine, which is subsequently cooled to a designated crystallization temperature by the cooling crystallizer. The cooling crystallizer crystallizes salt crystals from the cooled HPRO brine and produces a salt-diminished brine. The solids-liquid separator separates the salt-diminished brine from the salt crystals. The salt-diminished brine from the solids-liquid separator is returned to the HPRO unit for further treatment, which allows additional salts to be crystallized from the returned salt-diminished brine.

The present disclosure provides systems and methods that can treat feeds with elevated organic levels, e.g., feeds with ≥300 Pascals (Pa) organic osmotic pressure, with one or more enhanced filter membrane modules, which may be referred to herein as membrane modules or simply modules. Preferably, a filter membrane module consistent with the present disclosure include one or more plate and frame modules, one or more spiral format modules, or a combination of plate a frame and spiral format modules. The systems and methods provided herein can provide reliable performance when used to treat feeds with elevated organic levels.

The present invention provides, in various embodiments, hybrid single-pass tangential flow filtration assemblies, disposable single-pass tangential flow filtration assemblies, scalable single-pass tangential flow filtration assemblies and adaptable modular single-pass tangential flow filtration assemblies. In other embodiments, the invention relates to processes for recovering proteins from the surface of a filtration membrane in a single-pass tangential flow filtration assembly and for cleaning a tangential flow filtration assembly. In additional embodiments, the invention provides methods of increasing the processing capacity of a single-pass tangential flow filtration assembly.

Apparatus and method for semi-permeable membrane cleaning in particular, applying series of pulsed water stroke, made simultaneously with osmosis backward flow causing superposed membrane directional shaking and fouling detachment. Pulsed water stroke provided by water stroke generator as several momentum sharp changes in gauge pressure and induce velocity pulse of residual brine flow. The pulsed water strokes ideally induce resonance in the membrane. Osmosis backward wash may be provided either by injection for predetermined injection time, additional solution selected in such way that net driving pressure becomes opposite to normal osmotic operation thereby providing a backward flow of permeate towards to the side opposite to normal operation mode, so as to lift said foulant, or by throttling permeate exiting from the permeate enclosure, until the net driving pressure value become equal to zero, during application of precise synchronized and opposing brine and permeate pressure strokes thereby providing a plurality of quick RO-FO-RO process changes. These procedures allow a membrane to be kept continuously clean and operate at higher recovery.

A water treatment device includes a sub-reverse osmosis membrane device having a primary casing and a primary reverse osmosis membrane dividing the primary casing into a primary liquid passing part and a primary permeating part; a low pressure water feed pump feeding seawater to the primary liquid passing part at a pressure that is equal to or lower than an osmotic pressure of the seawater; a main reverse osmosis membrane device having a secondary casing and a secondary reverse osmosis membrane dividing an inside of the secondary casing into a secondary liquid passing part and a secondary permeating part; and a high pressure water feed pump feeding a primary treated liquid, which is a resultant product of the seawater passing through and flowing out of the primary liquid passing part, to the secondary liquid passing part at a pressure higher than an osmotic pressure of the primary treated liquid.

Disclosed herein are apparatuses and methods for semi-permeable membrane cleaning. In particular, a pressure retarded osmosis (PRO) process redirects raw solution and fluid streams in such a way as to cause periodic changes of the process from PRO to reverse osmosis (RO) for lifting and detaching fouling. Further disclosed is applying, at least periodically, a pulsed-flow regime in the fluid stream, thereby causing increased shearing force for enhanced evacuation of the foulant. Additionally, a backward wash may be provided by injection, for a predetermined injection time, of additional solution selected in such way that net driving pressure becomes RO opposite to normal PRO operation, thereby providing a backward flow from a first side of the membrane to a second side of the membrane, so as to lift and evacuate foulant.

An online cleaning system for micro-polluted nanofiltration membranes uses forward osmosis, and a process of the online cleaning system, and relates to the field of water treatment membrane separation technique. The online cleaning system includes a nanofiltration raw water tank, a nanofiltration membrane assembly, a pure water tank, a forward osmosis feed solution tank, a forward osmosis draw solution tank, a first saline water tank, a second saline water tank and a water bath temperature control device. Some embodiments include cleaning of the nanofiltration membranes that is realized by using forward osmosis as a nanofiltration membrane cleaning system, and cyclic regeneration of the nanofiltration membranes can be realized, so that the purposes of removing dissolved organic matters in micro-polluted raw water, reducing hardness of calcium and magnesium and prolonging the service life can be achieved.

Apparatus and method for semi-permeable membrane cleaning in particular, applying series of pulsed water stroke, made simultaneously with osmosis backward flow causing superposed membrane directional shaking and fouling detachment. Pulsed water stroke provided by water stroke generator as several momentum sharp changes in gauge pressure and induce velocity pulse of residual brine flow. The pulsed water strokes ideally induce resonance in the membrane. Osmosis backward wash may be provided either by injection for predetermined injection time, additional solution selected in such way that net driving pressure becomes opposite to normal osmotic operation thereby providing a backward flow of permeate towards to the side opposite to normal operation mode, so as to lift said foulant, or by throttling permeate exiting from the permeate enclosure, until the net driving pressure value become equal to zero, during application of precise synchronized and opposing brine and permeate pressure strokes thereby providing a plurality of quick RO-FO-RO process changes. These procedures allow a membrane to be kept continuously clean and operate at higher recovery.