An aerator assembly for wastewater treatment includes a draft tube and an air supply assembly. The draft tube includes a sidewall and presents open top and bottom tube ends. The air supply assembly includes an air supply conduit and a diffuser body. The diffuser body has an inlet aperture and a bubble generator connected to the inlet. The inlet aperture is connected to the air supply conduit such that the bubble generator receives air from a source of air, to which the air supply conduit is connected. The bubble generator has a plurality of air openings for generating fine air bubbles. The diffuser body is sealingly engaged to the sidewall adjacent the bottom tube end so as restrict upward flow of wastewater through the draft tube past the diffuser body.

Provided herein is a portable air purifier. The portable air purifier includes: a body; first to third accommodation portions configured to have respective open top surfaces in order to separately accommodate a battery, an air compressor, and water; first to third covers configured to selectively open and close the respective open top surfaces of the first to third accommodation portions; an air inlet connected to the lower portion of the second accommodation portion, and configured to accommodate a pre-filter; a siphon pipe positioned upright inside the water of the third accommodation portion, and configured such that the top thereof is connected to the air outlet of the air compressor; a cannula installed on the top of the third accommodation portion, and configured to supply purified, humidified air to a user; and a power switch configured to control the amount of air to be supplied.

A resistivity adjustment device includes: a hollow fiber membrane module that is divided by a hollow fiber membrane into a liquid phase side area; a liquid supply pipe that communicates with the liquid phase side area; a liquid discharge pipe that communicates with the liquid phase side area; a gas supply pipe that communicates with the gas phase side area; a gas discharge pipe that communicates with the gas phase side area; a bypass pipe that communicates with the liquid supply pipe and the liquid discharge pipe to bypass the hollow fiber membrane module; and a first on-off valve that is connected to the gas discharge pipe and opens or closes a first passage inside the gas discharge pipe, wherein the first on-off valve opens the first passage to discharge water accumulated in the gas phase side area.

Jet fuels' thermal oxidation characteristics are evaluated via the Standard Test Method for Thermal Stability of Aviation Turbine Fuels. This test method mimics the thermal stress conditions encountered by jet fuel in operation and is often carried out by laboratory devices, known as rigs. The rigs include a test section having a sleeve and a heater tube arranged therein. A pair of bus bars secure the test section to the rig and apply a current to the heater tube. The applied current heats the heater tube and subjects the sample jet fuels that are flowing in the volume between the sleeve and heater tube to high temperatures, which may produce thermal oxidation deposits on the heater tube. Heater tubes are difficult to install, however, and a gauge may be used to ensure accurate placement of the heater tube within the sleeve. In addition, the fuel sample must be prepared via an aeration process, and systems are disclosed for automating the aeration process such that the sample is prepared precisely according to the test standard. Moreover, the rig includes a pump system that moves the fuel sample through the test section, and a pump system is provided in a double syringe arrangement that optimizes fuel flow through the test section without fluctuation. Finally, the rigs include cooling systems for cooling the bus bars and maintaining an appropriate thermal profile within the heater tube, and cooling systems may be provided that independently control the temperature of each bus bar.

A system for separating solids from a first slurry mixture recovered from a hydrocarbon well. The system includes a V-shaped tank and one or more second mixing tanks for accumulating a slurry of fine particles from an overflow from the V-shaped tank. A shaftless auger moves solids to a conduit fluidly connected to hydrocyclones. The overflow of the hydrocyclones is mixed with the first flurry coming from a rig flow line and is discharged over a target plate and bar screen. Air is released from the mixture through one or more perforated baffles. Solids fall from the bar screen onto a shaker, which dewaters these solids as well as solids from an underflow from the hydrocyclones.

A method of air scouring an immersed membrane is described in this specification. The method comprising a step of adjusting one or more aeration parameters: between successive permeation, back pulse or relaxation cycles; during a permeation cycle; or, between a permeation cycle and a backpulse or relaxation cycle.

Embodiments of the present disclosure describe an aquaculture environment control system comprising one or more control apparatuses positioned within a vessel at an angle relative to a proximal vessel wall and configured for scouring of the vessel, wherein each control apparatus has a discharge conduit and each discharge conduit has one or more orifices; and a fluid source in fluid communication with each of the control apparatuses. Embodiments of the present disclosure describe a method of controlling an aquaculture environment comprising supplying one or more of a fluid and gas to a control apparatus positioned within a vessel at an angle relative to a proximal vessel wall; and discharging one or more of the fluid and gas from the control apparatus at a fluid velocity sufficient for scouring of the vessel.

The present invention is directed to a process for producing precipitated calcium carbonate with improved resistance to structural breakdown, wherein the milk of lime is carbonated in the presence of at least one gas other than carbon dioxide, or the carbonation is carried out in the presence of a static gas bubble comminution unit as well as to precipitated calcium carbonate obtained by such a process.

A system for mixing and mixing processes and structures are disclosed. In addition a nozzle used for mixing is disclosed.

A device for bubbling a gas into a liquid is disclosed. The device comprises a first bubbling apparatus nested inside a second bubbling apparatus. The first bubbling apparatus comprises a gas inlet for receiving the gas and a plurality of first openings for releasing the gas. The second bubbling apparatus at least partially encloses the plurality of first openings of the first bubbling apparatus. The second bubbling apparatus receives the gas from the plurality of first openings. The second bubbling apparatus comprises a plurality of second openings for bubbling the gas into the liquid.