Patent Application
20220401855
The invention patent is developed in the field of equipment to remove contaminating substances (crud) that are formed in solvent extraction processes, specifically it refers to an equipment to extract said contaminants that are formed in the interface between a phase of organic and an aqueous phase in the mixers-settlers (settlers).
The solvent extraction process consists of the purification and concentration by means of reagents of an organic nature of the solutions (PLS) that come out of the leaching heaps, in which said reagents selectively extract copper. In the solvent extraction process there is a copper extraction stage and a discharge stage (stripping) in order to obtain a purer and more concentrated solution (Rich Electrolyte) that then goes to the electrowinning stage. The stages of contact between the PLS or Poor Electrolyte with the organic reagent are carried out in a mixer-settler equipment (mixer-settler), generating in the decantation process the separation of an aqueous phase and an organic phase, the aqueous phase being of higher density remains under the organic phase. The PLS coming from the leach pads normally brings suspended solids that, in contact with the organic phase, generate a third phase that is evident in the decanter and is located between the organic phase and the aqueous phase. The substance present in this third phase is commonly called “loose” (crud) and is gelatinous in appearance, being composed of aqueous, organic and small amounts of fine solids. The sludge can influence the continuity of phases, the stability of the emulsion, the aqueous solution, the distribution of air, so the phases must be removed from the decanter and the drag from one phase to another, which contaminates the purity of the electrolyte. rich and produces losses of the organic phase.
In the state of the art, some documents can be mentioned that refer to the elimination of the sludge present in the interface between the organic phase and the aqueous phase in mixer-settlers in solvent extraction processes.
U.S. Pat. No. 4,126,551 can be cited disclosing an apparatus and method for handling solids in solvent extraction equipment, where said apparatus is used in combination with settlers and includes a retractable blade that moves along a tank containing the aqueous phase, the organic phase and the interface where the solids are found.
Another document to consider is US 2002020252, which discloses a process and equipment for extracting solids from the interface between the aqueous phase and the organic phase of a solvent extraction system. The equipment has an endless screw at or near said interface to extract the solids.
You can also consider the document CN104966537 that discloses a device and a method for removing crud from the interface of a pond with said device. The device comprises a liquid suction tube to extract liquid from the interface, a storage tank for the liquid it extracts, a filter medium to filter the liquid, retaining the crud, and a drainage tube to return the filtered liquid to the tank.
Finally, another document that should be mentioned is the patent CL 45923 that discloses a system for a mixer-settler equipment for solvent extraction plants, where a continuous and partial suction system is installed for emulsion of the dispersion band that is located in the organic-liquid interface at the end where the dispersion band touches the decanter outlet weirs, where the suction is carried out with an extraction receptacle and a dispersion duct.
None of the above documents teaches equipment such as that of the invention that allows for the selective extraction, by means of vacuum, of the sludge from the interface of solvent extraction processes in a manual and simple way that is easy to install and operate with a continuous process.
The invention discloses equipment for extracting sludge (crud) from the interface that is generated in a mixer-settler (mixer-settler) in a solvent extraction process between an aqueous phase and an organic phase. The equipment allows the continuous extraction, by means of vacuum, and the storage of said sludge, comprising a sludge collector; a vacuum system and a vacuum tank with a lid on its upper part with two connections and a lower valve connected to the vacuum system, to the sludge collector and to a pneumatic pump, in which said pump is connected on one side to the lower valve and on the other to a plurality of containers that receive the linters sucked up by the equipment. The contents of the containers subsequently go through a recovery process outside the mixer-settlers. The sludge collector is a transparent rigid tube mounted on floats with which, by rotating said rigid tube, it can be located and act on the interface to suck the sludge into it. The rigid tube of the sludge collector must be transparent so that the equipment operator can verify, when the equipment is in operation, that the sludge is properly extracted from the interface.
The invention relates to equipment for extracting sludge (crud) from the interface (5) that is generated in a mixer-settler (mixer-settler) (1) in a solvent extraction process between an aqueous phase (3) and an organic phase (4). The equipment comprises:
a sludge collector (2);
vacuum tank (6);
a pneumatic pump (8);
a plurality of containers (9);
a vacuum system (7); Y
flexible hoses (10,11,12,13);
The vacuum tank (6) receives the lees from the lees collector (2), comprising an outlet valve (15) located in its lower part and an upper cover with a first upper connection (16) and a second upper connection (17). The first upper connection (16) is connected by a flexible hose (10) to the lint collector (2) that extracts the lint. The second upper connection (17) is connected by means of a flexible hose (12) to the vacuum system (7), where said system (7) generates the vacuum inside the vacuum tank (6). The lower valve (15) allows the evacuation of the sludge from the vacuum tank (6) by pumping a pneumatic pump (8) for its storage in a plurality of containers (9). The lower valve (15) is connected to the pneumatic pump (8) by means of a flexible hose (13). The pneumatic pump (8) is connected to the plurality of containers (9) by means of a flexible hose (11).
The vacuum system (7) is made up of a cubicle in which there are turbines and air filters inside that generate the appropriate vacuum levels for the operation of the system (7) to produce suction or aspiration through vacuum in the sludge collector (2).
The sludge collector (2) comprises a transparent rigid tube (18) with a diameter between 6.35 mm. (¼″) and 76.5 mm. (3″) preferably being 50.8 mm. (two″); a plurality of floats (19) attached along the tube (18) that allow the sludge catcher (2) to float on the organic phase (4) on the surface of the mixer-settler (1); a tube elbow (20) at a first end of the transparent rigid tube (18) that projects perpendicular to the longitudinal axis (18′) to the transparent rigid tube (18) by means of a tube extension (20′), in the other end of the tube elbow (20), which ends in a suction nozzle (23) through which the lint enters the interface (5) to the lint collector (2), where said first end is on the surface of the liquid in the mixer-settler (1); and an angle change handle (21) located near a second end of the transparent rigid tube (18), opposite the first end, where the operator is located, which allows the sludge catcher (2) to rotate according to the axis longitudinal (18′) of the transparent rigid tube (18), where the rotation of the sludge catcher (2) is independent of the plurality of floats (19) The transparent rigid tube (18), the tube elbow (20) and the tube extension (20′) are made of a material resistant to acid and organic solvent extraction processes. The length of the tube extension 20′ can be increased by joining additional tube lengths connected by hermetic screw joints.
The assembly of the plurality of floats (19) with the transparent rigid tube (18) is free and has stops (25) fixed to the tube (18) in each of the floats (19) in order to prevent the longitudinal movement of said floats along the transparent rigid tube (18), Likewise, said assembly allows the rotation of the transparent rigid tube (18) with respect to the floats (19). The floats are made of any material that resists acid and organic with a lower density than organic, this is 0.84 gr/cm3, such as fishing net floats, dumplings, containers with internal air or the like.
As can be seen in
The equipment to suck and store the sludge obtained from the interface (5) between the aqueous (3) and organic (4) phases operates by connecting the vacuum system (7) to the vacuum tank (6) through the flexible hose (12) in the second upper connection (17) of the upper cover of the vacuum tank (6), in such a way as to achieve an adequate vacuum pressure to allow the suction of the sludge through the sludge collector (2).
For the suction from the interface (5), the sludge collector (2) is operated by placing it on the surface of the liquid in the mixer-settler (1) in such a way that it floats on the surface of said liquid on the organic phase (4). by means of the plurality of floats (19) in the transparent rigid tube (18). The vacuum generated in the vacuum tank (6) generates the suction of liquid from the mixer-settler (1) by means of a sludge collector (2). For a correct extraction of the lint, it is necessary to rotate the lint collector (2), with respect to the longitudinal axis (18′) of the transparent rigid tube (18) by means of the angle change handle (21), up to a suitable angle so that the suction nozzle (23) located at the first end of the transparent rigid tube (18) reaches the interface (5) where the lint is found. The operator must observe what is being pumped into the vacuum tank (6) through the transparent rigid tube (18) and when he notices that the sludge is being pumped from the interface (5), maintain the appropriate angle to continue with the operation of sludge suction. The operator can increase or decrease the suction pressure inside the transparent rigid tube (18) by opening or closing the extraction regulator valve (22) on the angle change handle (21).
The suction of the sludge inside the vacuum tank (6) towards the plurality of containers (9) is carried out through the lower valve (15) and by means of the pneumatic pump (8), connected by the flexible hoses (11,13).
The content recovered from the interface (5) and stored in the plurality of containers (9) is sent for processing outside the mixer-settler zone (1) of the solvent extraction process.
As shown in
The method to use the equipment to extract sludge (crud) from the interface (5) that is generated in a mixer-decanter (1) in a solvent extraction process between an aqueous phase (3) and an organic phase (4) includes the stages of
The adequate angle of rotation of the transparent rigid tube (18), to keep the suction nozzle (23) in the interface (5), is found by visually verifying the fluid that passes through the tube (18) until identifying the presence of you erase
During the operation of the equipment, the suction generated in the suction nozzle (23) is regulated by varying the suction pressure inside the transparent rigid tube (18) by opening or closing the extraction regulating valve (22) mounted on the handle. of change of angle (21) that is in communication with the interior of the transparent rigid tube (18) at one end and atmospheric pressure at the other end.
Subsequently, the plurality of containers (9) are transferred for processing out of the mixer-settler area (1) of the solvent extraction process.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202101592 | Jun 2021 | CL | national |
