Drinking water quality improvement using diferent adsorbent in household water filtration system

Podzemne vode glavni su izvor vode za piće za populaciju istočne Hrvatske, a sadrže povećane koncentracije arsena i huminskih tvari, koje prilikom dezinfekcije vode s klorom daju halogenirane spojeve štetne za ljudsko zdravlje. Stoga je iste potrebno ukloniti iz vode, odnosno smanjiti njihovu koncentraciju. To je moguće učiniti primjenom različitih adsorbenasa ili uporabom kućnih sustava za filtraciju vode.U radu je ispitano uklanjanje nepoželjnih tvari na vodovodnoj vodi grada Osijeka primjenom sljedećih adsorbenasa: granuliranog aktivnog ugljena (NORIT PK 1-3), antracita (Hydraffin 30n) i granuliranog željezo hidroksida (GEH®); te pomoću kućnog filtra (antracit + granulirani željezov hidroksid). Pratili su se sljedeći parametri: pH vrijednost, elektrovodljivost, koncentracija ukupnog arsena, koncentracija organskih tvari (utrošak KMnO4) i adsorpciju huminskih kiselina mjerenjem apsorbancije pri 254 nm. Rezultati istraživanja su pokazali da je adsorpcija huminskih kiselina najuspješnija na granuliranom aktivnom ugljenu (preko 80 % uklonjenih huminskih kiselina), zatim na GEH-u (do 60 %), a najslabija na antracitu (maksimalno 30%). Primjenom kućnog filtra koncentracija ukupnog arsena smanjena je za 20-45% od početne koncentracije u vodovodnoj vodi grada Osijeka tijekom istraživanja.Groundwater is the main source of drinking water in eastern Croatia and they are usually enriched with humic substances and arsenic. Humic substances are the end product of decaying organic matter, and during chemical water disinfection with substances such as chlorine, harmful disinfection byproducts can be formed. Arsenic is, in the other hand, well known as a poison, and recent epidemiological studies confirmed its carcinogenic effect in human body. That why those compounds are need to be removed from drinking water during drinking water treatment. Adsorption is one of most used techniques for arsenic and humic substances removal. Some studies reports also good results in arsenic and humic substances removal using household water filtration system. The removal of arsenic and humic substance from drinking water of Osijek town were investigated using granular activated carbon (NORIT PK 1-3), anthracite (Hydraffin 30n), granular iron dioxide (GEH®), and household filtration system made of anthracite and granular iron dioxide. The impact of following parameters on removal efficiency was observed: pH value, electrical conductivity, arsenic concentration, chemical oxygen demand (COD) and specific UV absorbance at 254nm. Obtained results shown effective removal of humic substances using granulated activated carbon (>80%) and granular iron dioxide (60%). The lowest humic substances removal, up to 30%, was achieved by anthracite. Using household filtration system made of anthracite and granular iron dioxide, arsenic concentration was reduced for 20 to 45% from initial concentration detected in Osijek’s drinking water during this study