Membránové technologie pro úpravu podzemních vod

Abstract

The deteriorating quality of groundwater poses a technological burden for the water supply sector, particularly in areas with intensive agriculture. This master’s thesis assesses the suitability of implementing nanofiltration and reverse osmosis for treating groundwater into drinking water from two hydrochemically distinct sources. The first is a stable source with moderate mineralization (Olomouc regional water supply), while the second is a source with very high hardness and a significantly fluctuating, often borderline nitrate content (Dub nad Moravou regional water supply). The thesis first defines the chemical profile of both locations based on long-term operational data and subsequently verifies the separation processes on the MMS SW18 laboratory unit using TS40-31 and ACM2-31 spiral-wound modules. Experimental results showed that reverse osmosis ensures high retention of all monitored ions; however, it produces practically demineralized water. Nanofiltration effectively reduces water hardness (calcium and magnesium retention of 70 to 90 %). Regarding nitrate retention, although nanofiltration achieves lower efficiencies than reverse osmosis, this degree of separation is still sufficient to safely reduce their concentration below the required hygienic limit. The thesis outcomes also confirm an increased risk of inorganic scaling when treating very hard waters.