Self-reciprocating energy recovery device

A self-reciprocating energy recovery device including a pair of power recovery chambers having pistons therein respectively, a high-pressure concentrated supply pipe, a low-pressure concentrated discharge pipe, and a high-pressure seawater discharge pipe to enable the power recovery chambers to recover hydraulic power supplied through the high-pressure concentrated water supply pipe and utilize the hydraulic power in driving of a seawater pump, the energy recovery device comprising:

• a fluctuating plate-like concentrated water valve having a fixed vane to selectively interrupt introduction and discharge of concentrated water to and from the first power recovery chamber and the second power recovery chamber through fluctuation thereof;
• a fluctuating plate-like concentrated water valve block having a space into which the fluctuating plate-like concentrated water valve and in which the fixed vane is accommodated and a first block outlet hole and a first block inlet hole, and a second block outlet hole and a second block inlet hole symmetrically disposed on opposite sides of the space;
• first and second high-pressure concentrated water pilots branched out from the high-pressure concentrated water supply pipe to pilots and connected to the first and second block inlet holes to alternately supply the high-pressure concentrated water;
• first and second high-pressure concentrated pilot valves interrupting supply of high-pressure concentrated water to the first and second high-pressure concentrated water pilots;
• first and second low-pressure concentrated water pilots connected to the first and second block outlet holes to alternately discharge the low-pressure concentrated water;
• and
• first and second low-pressure concentrated water pilot valves interrupting discharge of low-pressure concentrated water through the first and second low-pressure concentrated water pilots.