Ways to reduce fouling of separation membranes and increase the performance of membrane apparatus (a review)

Summary

The widespread use of membrane technologies in the energy sector in water purification processes, wastewater treatment and other areas poses questions of their improvement in order to increase the economic efficiency, performance of membrane separation apparatus, reduce the amount of secondary waste, etc. Potentials are being sought to improve these indicators. Moreover, if the highest level has currently been reached in the development and production of membranes, and no further dramatic improvements are visible so far, then in relation to the design it is believed that there are still potentials. The paper discusses options for increasing the efficiency of membrane separation apparatus by means of the external effects on the processed water or on the membrane apparatus. This is the pulsation of the liquid flow, ultrasonic impact on it, rotation of special inserts or the membranes themselves, vibrations of the membrane element. The complexity of their design and the prospects of application for different stages of purification and concentration processes are estimated.

Key words

membrane module , membrane technology , concentration polarization , reverse osmosis and nanofiltration plants , separating diaphragms , LF oscillations , ultrasonic waves , rotation , membrane vibrations , Roсhem apparatus , New Logic Research , VSEP system

VSEP Technology: how does it work?

Summary

The methods used in practice to increase the process efficiency of membrane separation of liquids as well as the most appropriate areas of their application are presented. Using the example of VSEP technology, theoretical estimates of the effect of hydrodynamic conditions on membrane separation processes are shown, where the membranes of a flat-plate module with open pressure channels are not hard-set fixed but subject to vibration in the form of sinusoidal rotary oscillations directed along the working surface. The main advantages of such processes are defined. The prospects for using VSEP technology in membrane separation processes are outlined. The importance of continuing the research trend and simulation of the hydrodynamic modes of liquid movement in pressure intermembrane channels is indicated.

Key words

VSEP technology , concentration polarization , New Logic Research , membrane separation of liquids , polarization phenomena , boundary layer , shear rate , sinusoidal membrane oscillations