Testing of water filtration device (and membranes removal characteristics)

I am doing my final year project as an undergraduate and am designing a brackish water filtration device that uses nanofiltration membranes.

I wanted to know if there is any suggestions on how I could test a membrane filtration device on a budget.

I am looking at simulation as a means of testing my design, but I cannot find a software that incorporates membranes.

If there are any suggestions on how I could test my device or any software recommendations please let me know.