Mixer settler plant

Complete turn-key multistage extraction unit

HIGHLIGHTS

• Multistage extraction plant incl. dosing pumps, intermediate receivers and piping
• Flow rates up to 4000l/h ( sum of both phases)
• Difference in density up to 5%
• Wide operating range
• Turn-Key units incl. control systems
• EX-rated pumps and stirrer drives
• Easy to modify
• Highly corrosion resistant for universal use
• Transparent for process optimization

CONCEPT

The mixer-settler-plants are turn-key units incl. piping, pumps and intermediate receivers for the continuous liquid/liquid extraction. Due to the high mixing performance of the stirrer system and the efficiency of the phase separation almost one theoretic stage can be realized per QVF® mixer-settler stage. Depending on the required product quality several of such separation stages are operated together in a counter current manner. The diameter of the QVF® mixer-settler stage is determined  by the required throughput. The length of the settler is determined by the required residence time of the phase settling process. Optionally the phase separators can be equipped with phase coalescers to speed up this process step and hence to shorten the length.

Within the given dimensional limits the phase ratio, throughput and mixing performance can be varied over a wide range to fit most different requirements. These adjustments can be realized quite easily since the pressure drop across the QVF® mixer-settler stage and the interconnecting piping is compensated by the stirrer over a wide speed range. The standard solution is a high speed QVF® turbine stirrer.

In case emulsions are generated due to the required pumping performance of the QVF® turbine stirrer alternative QVF® suction stirrers having a higher pumping performance at lower speed can be provided.

All components incl. the dosing pumps are QVF® components and hence compatible with the QVF® SUPRA-Line construction set system. This eases eventual hard ware adaptation of the plant to various extraction processes.

FUNCTION

The heavy phase is fed by the dosing pump P01 from the optional intermediate receiver B01 into the QVF® mixer-settler MIS01. The light phase is fed by dosing pump P02 from the optional intermediate receiver B02 into MIS02. The 2 phases are then guided counter currently through the mixer-settler system. The raffinate phase as well as the extract phase leave the QVF® mixer-settler stages via free overflows and are finally guided into the optional intermediate receivers B03 and B04. Mixing and pumping performance are controlled by the stirrer speed. The level of the interphase is adjusted by the overflow valves V1 and V2 for the heavy phase.

The feed rates are adjusted by the stroke length and frequency of the QVF® bellows-dosing pumps. The transferred volumes can be taken from the graduated intermediate receivers. The size of the intermediate receivers should permit the continuous operation of the extraction without any interruption.

OPTIONS

• Additional QVF® mixer-settler stages
• Jacketed version for tempering
• Coalescers for the settlers
• QVF® Suction stirrer made of borosilicate glass 3.3
• QVF® bellows dosing pumps
• Air vessels and flow meters
• Graduated intermediate receivers made of borosilicate glass 3.3
• Vent lines made of PFA or borosilicate glass 3.3
• Control cabinet
• Equipment for operation up to EX-zone 1 IIC