הנדסת מים

33 בריאות, חקלאות וסביבה ), ואינה יכולה להתבצע retrofit ההקשיה הקיים ( במערך קליטת המים המותפלים. בעקבות בחינת השיטות לעיל סוכם שיש לבדוק גם המסת דולומיט גרנולרי בעמודות/תאי הקשיה. לפיכך, מתוכנן לבצע בחינה זו במתקן חלוץ. במידת הצורך יבחנו שיטות נוספות. A Novel Technology for Magnesium Recovery in Desalinated Water: From Lab to Pilot Liat Birnhack, Paz Nativ and Ori Lahav Civil and Environmental Engineering, Technion The salt concentration in raw desalinated water is extremely low. As a result, while this water source is considered high quality, it is unsuitable for direct use in drinking, irrigation, or even delivery through the water distribution system. To address this, desalinated water undergoes post-treatment aimedat improving itsquality. Thecommonly appliedpost treatmentprocessescanprovide water that complies with the Israeli stringent quality standards. However, to date, no post- treatment process implemented in Israel supplies the magnesium levels required for public health. Moreover, although it is widely accepted that magnesium in drinking water is of high importance, it is rarely added to desalinated water in a cost-effective manner. In recent years, several innovative processes for adding magnesium to desalinated water have been developed in Professor Lahav’s research group. Some of these processes rely on the fact that seawater is both readily available and rich in magnesium. The main challenge, however, is to separate the dissolved magnesium and supply it to the desalinated water with minimal addition of sodium and chlorides, which are present at very high concentrations in seawater. In this lecture, we will present a membrane- based technology that enables the selective and cost-effective separation of magnesium from seawater, producing a magnesium sulfate solution. This solution, which is almost entirely free of undesirable ions is intended for dosing into desalinated water to replenish magnesium concentrations to levels required by the Ministry of Health. Importantly, this technology has been successfully implemented and tested in an operational pilot plant in Ma’agan Michael. The presentation will include results from the operation of the plant. The process involves several separation stages combining di f ferent types of nanofiltration membranes, including conventional steps and a key stage called diananofiltration (DiaNF). In the DiaNF step, monovalent ions are washed out from the retentate, which is then recycled back into the system feed while being diluted with clean water. The dilution with low-salinity water allows monovalent ions to pass into the permeate, progressively improving the ratio of magnesium to monovalent ions in the retentate as it is further diluted. The l ecture wi l l prov i de a deta i l ed presentation of the technology, a review of laboratory findings, pilot-plant performance data, and an economic assessment of magnesium production and its implications for the overall post treatment process. Additionally, we will discuss a potential application of the magnesium solution in the field of wastewater treatment.