Pressure exchanger unit for saving energy in desalination plants

A fluid pressure exchanger for converting a first high-pressure fluid stream to a second low-pressure fluid stream and a first low-pressure fluid stream to a second high-pressure fluid stream, the fluid pressure exchanger comprises a stator cylinder, side rotary discs, side-end casings, and a source of rotor motion;

• wherein the side rotary discs comprise at least a first rotary disc and a second rotary disc;
• longitudinal tubes in which pressure is exchanged between the first high-pressure fluid and the first low-pressure fluid;
• wherein the first rotary disc and the second rotary disc are connected by a rotor shaft;
• wherein the first rotary disc is covered by a first end casing, the first end casing having an inlet for entrance of the first high-pressure fluid and a first outlet for exit of the second low-pressure fluid stream;
• wherein the second rotary disc is covered by a second end casing, the second end casing having a second inlet for the entrance of the low-pressure fluid and a second outlet for the exit of the second high-pressure fluid stream;
• wherein the front face of the first rotary disc is provided with an internal circular channel, and an external circular channel, wherein the internal circular channel and the external circular channel are arranged in concentric spaced circles, the center thereof is the center of the front face of the first rotary disc;
• wherein the back face of the first rotary disc is provided with an upper semi-circular channel opposing a lower semi-circular channel;
• wherein the front face of the second rotary disc is provided with an internal circular channel and an external circular channel wherein said internal circular channel and said external circular channel are arranged in concentric spaced circles, the center thereof is the center of the front face of the second rotary disc;
• wherein the back face of the second rotary disc is provided with an upper semi-circular channel opposing a lower semi-circular channel;
• wherein the external circular channel of the front face of the first rotary disc, and the upper semicircular channel of the back face of the first rotary disc are connected via at least one hole;
• wherein the internal circular channel of the front face of the first rotary disc is connected to the lower semicircular channel of the back face of the first rotary disc via at least one duct, wherein the at least one duct has an open end in the internal circular channel of the front face of the first rotary disc and another open end in the lower semi-circular channel of the back face of the first rotary disc;
• wherein the external circular channel of the front face of the second rotary disc, and the upper semicircular channel of the back face of the second rotary disc is connected via at least one hole;
• and
• wherein the internal circular channel of the front face of the second rotary disc, and the lower semicircular channel of the back face of the second rotary disc is connected via at least one duct, wherein the at least one duct has an open end in the internal circular channel of the front face of the second rotary disc, and another open end in the lower semicircular channel of the back face of the second rotary disc.