Concentració de microalgues per membrana

Abstract

The use of microalgae has increased significantly in recent years, especially in

wastewater treatment plants or treatment plants, since microalgae use phosphorus

nitrogen and carbon dioxide as food, all elements or molecules that we are interested in

eliminating, although microalgae have been widely used in recent years for their reuse,

this has caused that it is crucial to find a method to do so, in a previous study of the same

research group, it was seen that when filtering the microalgae with a system without

pumping they are attached to the membrane reducing the filtration capacity of this, this

fact that it was a problem at that time we want to use it now to be able to obtain such a

separation from the aqueous medium to be able to reuse the already clean water. We

also want to compare two types of filtration, such as direct osmosis (FO) and

microfiltration (MF) to see which of the two we have the greatest capacity to attach the

microalgae and compare the ease with which we can detach them later without

damaging the membrane so that we can also reuse it. Likewise, 3 methods for the

quantification of microalgae were tested, of these methods dry weight has ended up

being used, since it offered us results more coherent with what we expected.

Once the membranes have been characterized and after obtaining a quantification

system of the microalgae, two five-day filtering for each type of membrane has been

carried out, replacing every day the microalgae that had not yet been attached by 8L with

new microalgae and a sample of both the microalgae that have not been attached to the

membrane has been quantified daily, and we have observed that with the microfiltration

membrane we have a greater capacity of recovery of the microalgae, of up to 60%, while

with the direct osmosis we only reach 30% recovery, but it is easier to recover them,

since they can be detached when filtering distilled water

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