Diseño y fabricación de válvula pulsante para generación de flujos variables en módulos de desalinización por ósmosis inversa

Abstract

It has been reported that pulsatile flow promotes greater

permeate in reverse osmosis (RO) operations through the

generation and shedding of vortices, increasing mass transfer

and hindering the onset of fouling through the effect of higher

shear rate. In this project, a valve has been manufactured that

generates pressure variations in water flow as determined by

simulation studies at pressures between 4826 and 6205 kPa,

flow rates in the range of 0.6 to 1.2 L/min, and a range of

frequencies from 10 to 45 Hz, in order to increase the permeate

flow in RO desalination modules. In addition, its performance

is experimentally tested. For its development, the engineering

design method is employed using Newton´s second law, the

conservation law –applying Bernoulli´s principles, as well as

the angular momentum equation. The best result using RO

membranes is under pulsatile flow induced in the feed flow at

Q = 0.6 L/min, p = 6205 kPa and f = 40 Hz when the flow is not

turbulent. The generated pulsatile flow increases the quantity of

permeated water, reduces the formation of fouling layers on the

membrane and consequently reduces the frequency of membrane

replacement. The pulsatile valve has the necessary requirements

in order to be part of any RO system.