Devices, methods, and systems for producing a concentrated feed stream and a diluted feed stream using a solute stream provided to the low pressure side of the semi-permeable membrane during a reverse osmosis process. The process includes providing a semipermeable membrane having a first side and a second side and introducing a first feed solution stream on the first side of the membrane and a second feed solution stream on the second side, wherein the osmotic pressure of the of the first feed solution stream is greater than or equal to the osmotic pressure of the second feed solution stream. The process further includes exerting hydrostatic pressure on the first side of the membrane such that solvent passes from the first side to the second side thereby producing a concentrated first feed solution stream and a diluted second feed solution stream. Devices and systems for performing the processes are provided.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

A reverse osmosis system comprises a permeate collection tube which is connected at one end to a distribution system for permeate which comprises at least one device for cleaning and/or disinfection. The permeate collection tube, the cleaning and/or disinfection device and a circulation pump are arranged in a circulation circuit.

The present invention relates to a process for the selective removal of nitrates from ground water using a hybrid nanofiltration (NF)reverse osmosis (RO) filtration system. The process generates product water that is low in nitrate and can be used for drinking, irrigation and other purposes, as well as waste water that is relatively low in salinity and can be safely discarded to sewage systems and recycled, e.g., for irrigation purposes.

Equipment, systems, processes and techniques for conducting processing of solutions are described. The techniques can be applied to provide diluted solution (i.e. purified solvent), concentrate solution or each. A variety of specific equipment, example systems and processes are depicted and described.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

Equipment, systems, processes and techniques for conducting processing of solutions are described. The techniques can be applied to provide diluted solution (i.e. purified solvent), concentrate solution or each. A variety of specific equipment, example systems and processes are depicted and described.

Equipment, systems, processes and techniques for conducting processing of solutions are described. The techniques can be applied to provide diluted solution (i.e. purified solvent), concentrate solution or each. A variety of specific equipment, example systems and processes are depicted and described.