A reverse osmosis desalination system has a combined displacement pump and displacement pressure recovery motor that propagate feed water with a structurally fixed recovery rate and struturally stabilized volume flow through continuously alternating discharging and recirculation intervals. Thereby enabled is an instantaneous discharge of the entire feed water concentrate and unmixed replacement with low salinity source water that intermittingly and effectively flushes the reverse osmosis membranes. This in turn provides for high recirculation peak salinity and recovery rate that are simple and reliably controlled without impairing membrane longevity.
A reverse osmosis desalination system has a combined displacement pump and displacement pressure recovery motor that propagate feed water with a structurally fixed recovery rate and structurally stabilized volume flow through continuously alternating discharging and recirculation intervals. Thereby enabled is an instantaneous discharge of the entire feed water concentrate and unmixed replacement with low salinity source water that intermittingly and effectively flushes the reverse osmosis membranes. This in turn provides for high recirculation peak salinity and recovery rate that are simple and reliably controlled without impairing membrane longevity.
A pump adapted for use in desalination systems that has four cylinders, with a double acting piston in each cylinder. Each cylinder and piston thereby defines a feed chamber and a recovery chamber. The pistons are connected to a common drive. The connection to the common drive is such that the pistons reciprocate in a sequence equally spaced in time. Reciprocating valving for each piston is driven by the common drive to be 90 degrees out of phase with the respective piston.
The valving connects the recovery chamber alternately to an inlet manifold for an intake stroke of the piston relative to the recovery chamber, and to an outlet manifold for a discharge stroke of the piston relative to the recovery chamber. There is a brief period of closure coinciding with top dead centre and bottom dead centre of the piston, during which the recovery chamber is blocked off from both the inlet and outlet manifolds. The reciprocating valving is midway between its top dead centre and bottom dead centre during the period of closure.
F04B 1/16 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders having two or more sets of cylinders or pistons
F04B 53/14 - Pistons, piston-rods or piston-rod connections
F04B 53/00 - Component parts, details or accessories not provided for in, or of interest apart from, groups or
F04B 1/053 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement with actuating or actuated elements at the inner ends of the cylinders
F04B 1/0538 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement with actuating or actuated elements at the inner ends of the cylinders with two or more serially arranged radial piston-cylinder units located side-by-side
F04B 9/04 - Piston machines or pumps characterised by the driving or driven means to or from their working members the means being mechanical the means being cams, eccentrics or pin-and-slot mechanisms
F04B 7/00 - Piston machines or pumps characterised by having positively-driven valving
C02F 1/44 - Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
F04B 5/02 - Machines or pumps with differential-surface pistons with double-acting pistons
A pump in desalination systems has four cylinders, each having a double acting piston. Each cylinder and piston defines a feed chamber and a recovery chamber. The pistons connect to a common drive. The connection to the common drive is such that the pistons reciprocate in a sequence equally spaced in time. Reciprocating valving for each piston is driven by the common drive to be 90 degrees out of phase with the respective piston. The valving connects the recovery chamber alternately to an inlet manifold for an intake stroke of the piston relative to the recovery chamber, and to an outlet manifold for a discharge stroke of the piston relative to the recovery chamber. A brief period of closure coincides with top dead centre and bottom dead centre of the piston, during which the recovery chamber is blocked off from both the inlet and outlet manifolds. The reciprocating valving is midway between its top dead centre and bottom dead centre during the period of closure.
F04B 1/16 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders having two or more sets of cylinders or pistons
F04B 1/14 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders
F04B 1/12 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
F04B 53/00 - Component parts, details or accessories not provided for in, or of interest apart from, groups or
F04B 1/053 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement with actuating or actuated elements at the inner ends of the cylinders
F04B 1/0538 - Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinders in star- or fan-arrangement with actuating or actuated elements at the inner ends of the cylinders with two or more serially arranged radial piston-cylinder units located side-by-side
F04B 9/04 - Piston machines or pumps characterised by the driving or driven means to or from their working members the means being mechanical the means being cams, eccentrics or pin-and-slot mechanisms
F04B 7/00 - Piston machines or pumps characterised by having positively-driven valving
F04B 5/02 - Machines or pumps with differential-surface pistons with double-acting pistons
Apparatus for killing and preventing growth of algae and bacteria in the piping, filtering and pumping components of watermaker systems during periods of non-use
An algae and bacteria contamination preventing apparatus and subsystem including a conduit forming a flush-water flow path between a potable water supply and a connection to a feed water entry port of a watermaker system. A check-valve and flush-water connector is installed in the feed water entry conduit. The flush-water flow path includes a valve means for opening and closing the flow path, a filter/ion-generator component a controller for sensing flush-water flow in the flow path, and in response thereto, applying electrical power to an ion-generating element of the filter/ion-generator component. The filter/ion-generator component also includes a filter element which removes undesirable chemicals from the potable flush-water before the ion-generating element introduces copper and/or silver ions into the flush-water. The valve means may be manually operated or be controlled by a watermaker system shut down controller.