Patent FR-2993877-A1 (FR)
Title: Installation, useful for treating an aqueous effluent charged with nitrogen from e.g. aquarium, comprises a reactor comprising catalyst, and a unit for pumping a part of recirculating flow of fluid from fluid chamber towards chamber
Inventor: BOUYSSOU JEAN-FRANCOIS
IPC: C02F1/58
Filed: 2012-07-24
Abstract: The installation for treating an aqueous effluent charged with nitrogen in the presence of a catalyst (3) on a porous support comprising two metals, comprises: a reactor (2) comprising the catalyst provided between a chamber of catalyst feed stream and a fluid chamber (5) for discharging the fluid flow from the catalyst; a unit (6) for pumping a part of the recirculating flow of fluid from the fluid chamber towards the chamber; and a feed device (7) for supplying hydrogen gas and/or formic acid to a recirculating circuit. The installation for treating an aqueous effluent charged with nitrogen in the presence of a catalyst (3) on a porous support comprising two metals, comprises: a reactor (2) comprising the catalyst provided between a chamber of catalyst feed stream and a fluid chamber (5) for discharging the fluid flow from the catalyst; a unit (6) for pumping a part of the recirculating flow of fluid from the fluid chamber towards the chamber; and a feed device (7) for supplying hydrogen gas and/or formic acid to a recirculating circuit. The first metal comprises copper, tin, zinc, indium, nickel, silver, iron, cobalt, or germanium. The feed device is connected with the recirculation circuit placed downstream from a throttle equipping the recirculation circuit to permit recirculation of hydrogen gas by a venturi effect. The feed device is formed by an electrolysis device including two electrodes to produce hydrogen and oxygen, respectively. The electrodes are placed in compartments of the electrolysis device. One of the compartments of the electrode producing oxygen is provided with a vent for an evacuation of oxygen in the atmosphere. The compartment of the electrode producing hydrogen communicates with the recirculation circuit via a tube radial to the recirculation circuit and placed downstream from the throttle of the recirculation circuit. The tube emerges in the compartment of the electrode producing hydrogen or in a space communicating with the compartment. A formic acid feeding attachment includes a formic acid tank, a pump for supplying formic acid to the recirculation circuit from the tank, a pH measuring unit to measure the pH of the recirculation circuit, and a unit for controlling the pump according to data provided by the pH measuring unit. The fluid chamber is provided with a unit for separating gas/liquid such as a baffle, an upstream compartment and a downstream compartment for a circulation by overflow of the upstream compartment towards the downstream compartment. The pumping unit is present in an entry placed in the downstream compartment below an overflow area. The chamber comprises an input for supplying fluid independent of an outlet of the recirculation circuit in the chamber. The pumping unit comprises two outputs. The input of the chamber independent of the outlet of the recirculation circuit and the output of evacuation of flow of fluid outside the reactor are connected to an installation of modification of mineralization of the effluent to be treated such as an electrodialyzer. The electrodialyzer includes two electrodes placed inside an enclosure and a set of anionic and cationic membranes alternatively placed between two series of cells. Each cell of the first series of cells is provided with a fluid input and a fluid output. The fluid inputs are in communication with a fluid distributor. The fluid outputs emerge in a fluid collector. The fluid distributor is connected to the output of evacuation of flow of fluid outside the reactor. The fluid collector is connected to the input of supply flow of fluid. Each cell of the second series of cells is provided with an input and an output of fluid. The electrodialyzer further comprises a probe for measuring a dissolved total salt concentration of the effluent and a unit for inverting a polarity of the electrodes according to data provided by the probe.