Groundwater has been a preferred source of drinking water because of the general perception that it is of higher quality, less vulnerable to contamination, and requires less intensive treatment than other types of water. In fact, groundwater is susceptible to contamination by iron, manganese, and arsenic found in soil and rock. The Pall Aria™ microfiltration membrane system can successfully remove these contaminants.
Iron and manganese removal
Iron and manganese are secondary aesthetic contaminants in groundwater. They produce red and brown stains, giving the water the appearance of being impure. The consequence is reduced consumer confidence in your product.
You can eliminate iron and manganese using an oxidation process that precipitates these dissolved metals into particulate. The particulate can then be filtered out using a Pall Aria™ system.
Process flow using Pall Aria system to remove iron from groundwater
Process flow using Pall Aria system to remove manganese from groundwater
High arsenic levels in groundwater are common in certain regions. Naturally occurring arsenic is found in two forms: arsenate [As(V)] and arsenite [As(III)]. Under typical groundwater conditions, arsenate is more common and is easier to remove using coagulation and membrane filtration. An oxidation process can be used to convert arsenite to arsenate for coagulation/filtration.
Even when arsenic levels in the feedwater are high, the Pall Aria system can reduce arsenic below the maximum contaminant level when a coagulant dose of 15 mg/L of ferric chloride and proper pH control is used. Independent testing by NSF International Drinking Water Systems Center has shown that the Pall Aria system reduces arsenic to undetectable levels (<2 ppb). This is below the level required by the United States Environmental Protection Agency (US EPA) Arsenic Rule.