Abstract: A process for treatment of an effluent, which comprises an injection (3) into the effluent, of CO2 or of a mixture comprising CO2, comprising: a. a measurement of the pH (6) of the effluent is carried out upstream of the point of injection of the CO2 or of the mixture in the process; b. a curve of dose of CO2 to be injected as a function of the pH of a medium for a predetermined volume in litres or in cubic metres was determined beforehand, and this curve is entered into a regulator or automaton (4) capable of controlling the operation of the process; c. the presence of a flow of effluent to be treated is detected, and the dose of CO2 or of mixture, determined by said curve and multiplied by the flow rate of effluent to be treated, is injected.

Abstract: A method for treatment of an industrial effluent with aluminum, comprising: the effluent to be treated is carried to a first zone constituted by a tank having a pH of less than 9.5, so as to promote precipitation of the aluminum in aluminum hydroxide form and to facilitate its removal; a second zone is available and the recirculation of a part of a medium located in the zone 1 to the zone 2 and then return to the zone 1, and the injection of gaseous CO2 into the recirculated medium, are arranged; the solid particles formed in the zone 1 are separated and discharged; wherein in view of the recirculation of the medium where CO2 has been injected, the amount of dissolved CO2 available in the zone 1 is 0.5 to 3 times greater than the requirement necessary for the precipitation of the incoming effluent.

Abstract: A method for removing calcium from an industrial effluent loaded with calcium, comprises the effluent (10) is led into a zone equipped with a settler (12); a part of the effluent is diverted (13), part withdrawn at the settler outlet, part of between 3% and 25% of the flow exiting from the settler, part withdrawn downstream of a high-pressure pump (9), operating at a pressure typically of between 8 and 10 bars; at least one injection (15) of gaseous CO2 into the diverted stream is carried out, thus producing a reduction in the pH of the diverted stream within the range extending from 4 to 6.8, preferably within the range extending from 4.5 to 6; the return of the diverted stream thus treated to the initial effluent, before its arrival in the settler, or to the settler proper is arranged.

Abstract: The invention relates to a method for the in-line processing of liquid or pasty or semi-liquid media or further, media which contain solid elements in a liquid base, in pipe for conveying the medium between two steps in a plant by direct injection of a cryogenic fluid into the pipe, characterized in that the method uses, for the injection into the pipe, an injection device including a hollow cylindrical body in which a valve urged by a spring is inserted, said injection device including a through-channel substantially parallel to said valve and supplied with a pressurized cryogenic fluid, wherein one end of the through-channel is connected to the cryogenic fluid supply system while the opposite end opens at the seat of the valve.

Abstract: A method and an apparatus for injecting two-phase (gas+solid) carbon dioxide into a gas stream. Liquid carbon dioxide is cryogenically expanded into two-phase carbon dioxide, which is then injected into the center of the stream. An inerting gas is also injected into the stream along with the two-phase carbon dioxide.

Abstract: A method and an apparatus for injecting two-phase (gas+solid) carbon dioxide into a gas stream. Liquid carbon dioxide is cryogenically expanded into two-phase carbon dioxide, which is then injected into the center of the stream. An inerting gas is also injected into the stream along with the two-phase carbon dioxide.

Abstract: Method and its associated device for the regulated injection of liquid carbon dioxide (CO2L) into a liquid (L) under pressure inside a chamber. The liquid carbon dioxide (CO2L) is, according to this method, injected at a fixed flow rate, in stepped mode, under the protection of a stream of gas (when injection is stopped).