Ejector, fine solid piece recovery apparatus and fluid conveyor

A fine solids recovery apparatus for sucking and conveying fine solids by a pneumatic conveyor and recovering the fine solids, the recovery apparatus comprising

• an ejector along a conveying pipeline of the pneumatic conveyor, the ejector being configured to provide a conveying air stream,
• a cyclone separator configured to convey the conveying air stream flowing from the pneumatic conveyor into a cylindrical separation column, thereby forming a swirling stream by an energy thereof, exhausting air drawn to a center of the swirling stream, and recovering fine solids that centrifugally centriugally collides with a circumferential wall, and
• the ejector comprising a convergent-divergent nozzle having a throat between a suction port and a discharge port, jet blowing holes being provided in the convergent-divergent nozzle for jetting a jet stream from the upstream to the downstream of the throat thereby forming a negative pressure, pressure control holes providing an opening downstream of the jet blowing holes to communicate with a pressure space at a pressure level higher than a negative pressure formed by the jet stream and lower than a static pressure of the jet stream and the inside of the convergent-divergent nozzle.

A fluid conveyor for conveying material to be conveyed together with a conveying fluid through a pipe, the fluid conveyor comprising

• an ejector provided along a conveying pipeline that extends from conveyance source to the conveyance destination, said ejector configured to form and to convey a conveying stream to the conveyance destination,
• the ejector comprising a convergent-divergent nozzle having a throat between a suction port and a discharge port, jet blowing holes being provided in the convergent-divergent nozzle for jetting a jet stream from the upstream to the downstream of the throat thereby forming a negative pressure, pressure control holes providing an opening to downstream of the jet blowing holes to communicate with a pressure space at a pressure level higher than a negative pressure formed by the jet stream and lower than a static pressure of the jet stream and the inside of the convergent-divergent nozzle.