Abstract:
Disclosed is a clarifier for use in treating a liquid containing non-soluble particles in suspension in order to separate these particles from the liquid. It comprises a tank, a liquid supply duct opening into the bottom portion of the tank and an injector for injecting a gas under pressure into at least part of liquid supplied to the supply duct in order to saturate this liquid with said gas and thus to generate gas bubbles as the saturated liquid is subject to depressurization within the tank. The gas bubbles that are so-generated adhere to the particles in suspension in the liquid and lift them up to form a floating layer of sludge in the top portion of the tank. A scraper is provided in the top portion of the tank for skimming off the layer of sludge while it is formed. A plurality of plates extend at an angle within the tank above the supply duct. These plates define a set of upwardly inclined channels each having an upper end that is opened and through which the liquid fed into the tank may enter the channel. A liquid outlet mounted within the lower end of each channel to collect and remove from the tank the liquid that has been treated within the same. Thanks to its shape and structure, this clarifier occupies a surface area on the ground that 50 % or less smaller than any known clarifier of the same capacity. Its structure also permits to maintain much more microbubbles of requested size for a same amount of injected air in order to increase the probability of contact between the particles and the air bubbles.
Abstract:
Disclosed is a centrifugal liquid pump, preferably of the rotary disc type, which incorporates a gas injection assembly of very simple yet efficient structure, whereby up to 15 % per volume of a gas such as air may be mixed with the pumped liquid. The gas injection is achieved with a gas feed pipe (33) that enters the pump through its axial inlet and with a plurality of gas injector pipes (41) that projects from the gas feed pipe radially within the impeller.