Abstract: Disclosed is a stirring device (D) including a screw shaft (1) driven by a drive unit, the screw shaft (1) being guided with respect to a body by way of a bearing, the stirring device furthermore including a seal (8) rigidly secured to the body and in contact with the ball joint (7) so as to ensure sealing with respect to the fluid to be stirred. The seal (8) is mounted on a seal holder (9), the seal holder (9) including a contact region (10) and being able to take up two positions, a first, operating position in which the seal (8) is in contact with the ball joint (7), and a second, maintenance position in which the contact region (10) is in contact with the ball joint (7).

Abstract: Stirrer (M) that includes at least two blades and is able to be fixed to a rotary shaft, wherein each blade has a leading edge facing the fluid to be stirred and a trailing edge facing away from the leading edge, and wherein each blade is obtained by bending a flat metal sheet, each blade having two longitudinal bends, the length of each bend being greater than 60% of the maximum radius of the blade.

Abstract: The invention relates to a pump comprising a dosage head (1) comprising a first part (2) and a second part (7) in which there is provided a hydraulic chamber (8) which is filled with a fluid and a dosage body (14) comprising means for driving a piston (13) of the pump in translation in the hydraulic chamber, a valve (17) for regularization of pressure in the hydraulic chamber, and at least one degassing path (33, 34, 36, 37) which extends in the second part, such that a first end of the path which forms the lowest point of the said path opens out at a junction between the piston and a seal fitted on the piston, and a second end of the path which forms the highest point of the said path opens out into a hollow body of the said valve.

Abstract: A method for the lagoon-based bioleaching of a metallic ore, wherein the temperature of the suspension containing the metallic ore to be bioleached, a bioleaching consortium and a nutritive substrate of the microorganisms of the consortium is controlled by regulating the flows and the composition of a gas containing oxygen and optionally also CO2 injected into the suspension, the temperature of the suspension being controlled such that it can be maintained within a pre-determined range suitable for bioleaching.

Abstract: A hydraulically-controlled diaphragm pump including a pump chamber formed between a pump head and a pump body, a constant volume intermediate hydraulic chamber formed in the pump body and including a piston driven with reciprocating motion inside the intermediate chamber, a leak compensation volume for compensating leaks from the intermediate chamber being connected thereto by a top-up channel via a free check valve that is not rated and that passes fluid towards the working chamber. The check valve and at least a portion of the compensation volume are housed in a body fitted to the pump body at the high point of the intermediate hydraulic chamber in the working position of the pump.

Abstract: A device for detecting breaks in a diaphragm of a hydraulically-actuated pump includes a body (21) in which a first chamber (22) is formed, a duct (23) connecting the first chamber to a second end of the body, a check valve (24) arranged in the duct to pass fluid from the second end towards the first chamber, a piston (26) having a first portion (27) that co-operates in sealed manner with the first chamber and that has a hole passing therethrough of diameter greater than the diameter of a free ball (25) of the check valve, and a second portion (33) that is suitable for co-operating in sealed manner with the first portion to form a closed end of the piston. A method of mounting such a device on a pump, and a pump fitted with such a device, are also provided.

Abstract: A hydraulically-controlled diaphragm pump having a pump head in which a first deformable diaphragm defines a pump chamber, a pump body that co-operates with the first diaphragm to define a hydraulic working chamber, and a piston mounted to move back and forth in the pump body so as to form a controlled movable wall of the working chamber. The movable wall also includes at least one second diaphragm secured to the piston head and to the body of the pump, and providing sealing for the working chamber.

Abstract: The invention provides a pump, in particular for a chemically reactive fluid, in which a pump head comprises at least two walls between which there is defined a pump chamber for pumping the fluid in question, one of the walls being stationary, the other wall being movable or deformable relative to the stationary wall by means of a drive or deformation device, at least the stationary wall being provided with a protective coating against the fluid, wherein the coating is constituted by a sheet of plastics material applied in leaktight manner against the wall at the periphery thereof, with the space between the protected surface and the coating sheet, within the zone where they make leaktight contact, being filled with an incompressible liquid.

Abstract: A diaphragm pump including, in a pump body, a hydraulic control chamber disposed between a piston for executing reciprocating motion and the diaphragm, the pump including elements for compensating leaks from the hydraulic chamber, the elements including a refilling duct opening out into the hydraulic chamber via a normally-closed compensation shutter that is driven into the open position by the diaphragm, wherein the above-mentioned compensation shutter being driven by the diaphragm pressing against a free end of a rod for controlling the shutter, the diaphragm being subjected to the force of a suction-assistance spring which co-operates with the above-mentioned shutter to return it to its closed position by pushing the free end of the control rod back towards the diaphragm, the spring co-operating with the shutter to form a moving assembly that is moved without being deformed by the diaphragm during suction overtravel.