Abstract: A method of treatment of liquid in a liquid treatment system comprising: at least one liquid treatment module including at least one membrane and having a feed liquid inlet at a feed side of said at least one membrane, a permeate outlet at a permeate side of said at least one membrane, and a concentrate outlet at a brine side of said at least one membrane; a high pressure pump operative for pressurizing feed liquid to be received at said feed liquid inlet; and a system controller for controlling operation of the system including providing instructions to operate said high pressure pump in one of at least two operation modes including: a first mode in which the high pressure pump maintains a fixed flow rate of the feed liquid at said feed liquid inlet or of a permeate liquid at said permeate outlet, while energy consumption of said high pressure pump being a function of variations of a first operational parameter measured in the system and indicative of salinity of liquid within said at least one liquid treatm

Abstract: A water desalination system including at least one reverse osmosis desalination unit, including at least one reverse osmosis membrane and having a saline water inlet at a feed side of the at least one reverse osmosis membrane and a permeate outlet at a permeate side of the at least one reverse osmosis membrane, and an intermittent cleaning control subsystem operative to provide intermittent cleaning of the at least one reverse osmosis membrane by at least one of narrowing or closing the permeate outlet, thereby causing an increase of pressure of the permeate at the permeate side of the at least one reverse osmosis and reducing the feed pressure, without significantly increasing the permeate pressure, thereby causing permeate to flow from the permeate side to the feed side of a membrane and flushing foulants to a location outside of the desalination unit.

Abstract: A method of treatment of liquid including supplying liquid to be treated to at least one liquid treatment module having a liquid inlet, a permeate outlet and a brine outlet, monitoring liquid pressure within the at least one liquid treatment module and upon exceedance of a liquid pressure threshold in the at least one liquid treatment module, reducing the liquid pressure in the at least one liquid treatment module by performing at least one of the following functions: opening a liquid pressure reducing valve at the brine outlet, increasing a liquid volume output of a circulation pump which removes brine from the at least one liquid treatment module, equilibrating liquid pressures between a liquid pressure inside the at least one liquid treatment module and inside a liquid feed tank and opening a liquid pressure reducing valve at the liquid inlet.

Abstract: A method of treatment of liquid in a liquid treatment system comprising: at least one liquid treatment module including at least one membrane and having a feed liquid inlet at a feed side of said at least one membrane, a permeate outlet at a permeate side of said at least one membrane, and a concentrate outlet at a brine side of said at least one membrane; a high pressure pump operative for pressurizing feed liquid to be received at said feed liquid inlet; and a system controller for controlling operation of the system including providing instructions to operate said high pressure pump in one of at least two operation modes including: a first mode in which the high pressure pump maintains a fixed flow rate of the feed liquid at said feed liquid inlet or of a permeate liquid at said permeate outlet, while energy consumption of said high pressure pump being a function of variations of a first operational parameter measured in the system and indicative of salinity of liquid within said at least one liquid treatm

Abstract: A method of treatment of liquid including supplying liquid to be treated to at least one liquid treatment module having a liquid inlet, a permeate outlet and a brine outlet, monitoring liquid pressure within the at least one liquid treatment module and upon exceedance of a liquid pressure threshold in the at least one liquid treatment module, reducing the liquid pressure in the at least one liquid treatment module by performing at least one of the following functions: opening a liquid pressure reducing valve at the brine outlet, increasing a liquid volume output of a circulation pump which removes brine from the at least one liquid treatment module, equilibrating liquid pressures between a liquid pressure inside the at least one liquid treatment module and inside a liquid feed tank and opening a liquid pressure reducing valve at the liquid inlet.

Abstract: A method of treatment of liquid including supplying liquid to be treated to at least one liquid treatment module having a liquid inlet, a permeate outlet and a brine outlet, monitoring liquid pressure within the at least one liquid treatment module and upon exceedance of a liquid pressure threshold in the at least one liquid treatment module, reducing the liquid pressure in the at least one liquid treatment module by performing at least one of the following functions: opening a liquid pressure reducing valve at the brine outlet, increasing a liquid volume output of a circulation pump which removes brine from the at least one liquid treatment module, equilibrating liquid pressures between a liquid pressure inside the at least one liquid treatment module and inside a liquid feed tank and opening a liquid pressure reducing valve at the liquid inlet.

Abstract: A method of treatment of liquid including supplying liquid to be treated to at least one liquid treatment module having a liquid inlet, a permeate outlet and a brine outlet, monitoring liquid pressure within the at least one liquid treatment module and upon exceedance of a liquid pressure threshold in the at least one liquid treatment module, reducing the liquid pressure in the at least one liquid treatment module by performing at least one of the following functions: opening a liquid pressure reducing valve at the brine outlet, increasing a liquid volume output of a circulation pump which removes brine from the at least one liquid treatment module, equilibrating liquid pressures between a liquid pressure inside the at least one liquid treatment module and inside a liquid feed tank and opening a liquid pressure reducing valve at the liquid inlet.

Abstract: A water desalination system including at least one reverse osmosis desalination unit, including at least one reverse osmosis membrane and having a saline water inlet at a feed side of the at least one reverse osmosis membrane and a permeate outlet at a permeate side of the at least one reverse osmosis membrane, and an intermittent cleaning control subsystem operative to provide intermittent cleaning of the at least one reverse osmosis membrane by at least one of narrowing or closing the permeate outlet, thereby causing an increase of pressure of the permeate at the permeate side of the at least one reverse osmosis and reducing the feed pressure, without significantly increasing the permeate pressure, thereby causing permeate to flow from the permeate side to the feed side of a membrane and flushing foulants to a location outside of the desalination unit.

Abstract: A water desalination system including at least one reverse osmosis desalination unit, including at least one reverse osmosis membrane and having a saline water inlet at a feed side of the at least one reverse osmosis membrane and a permeate outlet at a permeate side of the at least one reverse osmosis membrane, and an intermittent cleaning control subsystem operative to provide intermittent cleaning of the at least one reverse osmosis membrane by at least one of narrowing or closing the permeate outlet, thereby causing an increase of pressure of the permeate at the permeate side of the at least one reverse osmosis and reducing the feed pressure, without significantly increasing the permeate pressure, thereby causing permeate to flow from the permeate side to the feed side of a membrane and flushing foulants to a location outside of the desalination unit.