A submersible aeration apparatus includes an air passage formed on a pump chamber to draw air into the pump chamber. A suction port formed on a lower side of the pump chamber draws liquid into the pump chamber. An impeller draws air through the air passage and liquid through the suction port. An ejection passage ejects the air and liquid. The impeller includes a main plate portion to cover a connection port connecting the air passage to the pump chamber. A vane portion protrudes downward from a lower surface of the main plate portion on the suction port side. The main plate portion has a cut-out part connecting the air passage and the pump chamber, and a groove part recessed from an upper surface of the main plate portion toward the lower surface and extending from an inner peripheral side toward an outer peripheral side of the main plate portion.

A submersible aeration apparatus includes an air passage formed on a pump chamber to draw air into the pump chamber. A suction port formed on a lower side of the pump chamber draws liquid into the pump chamber. An impeller draws air through the air passage and liquid through the suction port. An ejection passage ejects the air and liquid. The impeller includes a main plate portion to cover a connection port connecting the air passage to the pump chamber. A vane portion protrudes downward from a lower surface of the main plate portion on the suction port side. The main plate portion has a cut-out part connecting the air passage and the pump chamber, and a groove part recessed from an upper surface of the main plate portion toward the lower surface and extending from an inner peripheral side toward an outer peripheral side of the main plate portion.

A method for operating a pump includes establishing a pump limit characteristics diagram by mapping a first system parameter (P1) as a function of a second system parameter (P2) to identify a permissible operating region of the pump; for each first system parameter value (P1.sub.0), identifying a minimum allowable second system parameter value (P2.sub.0); monitoring the first system parameter (P1) and identifying a minimum allowable second system parameter value (P2.sub.0) corresponding to the monitored first system parameter value (P1.sub.m); monitoring the second system parameter (P2) and comparing the monitored second system parameter value (P2.sub.m) with the identified minimum allowable second system parameter value (P2.sub.0); and regulating a control valve that controls fluid flow through a return line connecting the suction and discharge sides of the pump so that the monitored second system parameter value (P2.sub.m) does not fall below the minimum allowable second system parameter value (P2.sub.0).

An impeller wake vortex dissipation device under stall condition of a mixed flow pump includes a guide vane and a wake vortex dissipation device. The pump is evenly divided into n guide vane channels by N evenly distributed guide vanes. A wake vortex dissipation device is set in each guide vane channel, and one end of the wake vortex dissipation device is fixedly connected to the inner wall of the pump body. Therefore, each wake vortex dissipation device is located in the middle and upper part of the guide vane channel and does not occupy the lower guide vane channel; the wake vortex dissipation device is provided with a dissipative hole pair, which are used to dissipate the energy of the wake vortex of the impeller.

A method of cleaning deposited solid material from a fouled portion of a gas compressor whilst the gas compressor is in situ in a natural gas processing system is provided. The method comprises the steps of supplying a liquid cleaning agent to a gas inlet of the gas compressor, the liquid cleaning agent being capable of removing the deposited solid material; passing the liquid cleaning agent through the gas compressor to a gas outlet of the gas compressor, wherein at least a portion of the cleaning agent remains in a liquid state as it passes through the fouled portion of the gas compressor; and recovering a fluid containing removed material that is output from the gas compressor so as to prevent the removed material reaching one or more gas processing stages of the gas processing system downstream of the gas compressor.

A pump for circulating water includes an upper housing formed with an inlet and an outlet of fluid; a lower housing installed to fit in a lower side of the upper housing, having a receiving space formed therein; an inner housing having an edge part interposed between the upper housing and the lower housing, an impeller receiving groove formed therein, and a shaft support part formed at the center of the bottom of the impeller receiving groove; an impeller received in the impeller receiving groove to be rotatably installed, so as to form a flow pathway between the impeller and an inner surface of the inner housing for the flow of fluid; a rotor installed inside the impeller; and a stator installed in the lower housing to be positioned to face the rotator.

A pump for circulating water includes an upper housing formed with an inlet and an outlet of fluid; a lower housing installed to fit in a lower side of the upper housing, having a receiving space formed therein; an inner housing having an edge part interposed between the upper housing and the lower housing, an impeller receiving groove formed therein, and a shaft support part formed at the center of the bottom of the impeller receiving groove; an impeller received in the impeller receiving groove to be rotatably installed, so as to form a flow pathway between the impeller and an inner surface of the inner housing for the flow of fluid; a rotor installed inside the impeller; and a stator installed in the lower housing to be positioned to face the rotator.

Disclosed are a control circuitry and control method applied to a pumping device, the pumping device, and aquarium equipment. The pumping device is used for pumping water and air. The control circuitry includes: a detection and feedback circuit that obtains a working state of the pumping device and transmits the working state to a signal processing circuit; the signal processing circuit that adjusts in real time a drive signal to be sent to a power drive circuit according to the working state information; and the power drive circuit that drives a motor in the pumping device to operate according to the drive signal. The motor is controlled to operate at a first rotational speed in a water pumping state, and to operate at a second rotational speed in an air pumping state, where the first rotational speed is lower than the second rotational speed.

A centrifugal pump includes a pump housing having a suspension inlet and a suspension outlet and a flow channel between the inlet and the outlet, a shaft mounted by bearings for rotation about a center axis, an impeller which is rotatable by the shaft, in alignment with the inlet and arranged to be rotated about the axis in the flow channel, and gas collecting openings for gas removal arranged in the flow channel. The inlet end of the flow channel includes a number of static vanes comprising gas collecting openings, the vanes extend radially from an inner wall of the flow channel toward the center of the flow channel and are upstream of the impeller.

A submersible aeration apparatus includes an air passage formed on a pump chamber to draw air into the pump chamber. A suction port formed on a lower side of the pump chamber draws liquid into the pump chamber. An impeller draws air through the air passage and liquid through the suction port. An ejection passage ejects the air and liquid. The impeller includes a main plate portion to cover a connection port connecting the air passage to the pump chamber. A vane portion protrudes downward from a lower surface of the main plate portion on the suction port side. The main plate portion has a cut-out part connecting the air passage and the pump chamber, and a groove part recessed from an upper surface of the main plate portion toward the lower surface and extending from an inner peripheral side toward an outer peripheral side of the main plate portion.