Arsenic removal

Arsenic occurs naturally in many geological formations and can enter the drinking water system via groundwater. Due to its toxicity, arsenic is hazardous to health even in low concentrations. The legally stipulated limit value for arsenic in drinking water is 10 µg/l according to the Drinking Water Ordinance. Special filter processes are used to ensure that this limit is adhered to.

Arsenic removal process:

• Arsenic is removed by adsorption onto a granulated filter material based on iron(III) hydroxide.
• The iron(III) hydroxide binds dissolved arsenic from the water. This produces iron arsenate, which is difficult to dissolve. The bound arsenic can be partially removed by regularly backwashing the filter system. The filter material has a limited capacity and is consumed over time, so regular checks and, if necessary, replacement are required.

Technical features:

• Filtration is usually carried out using a single or dual filter system with an automatic backwash function.
• The systems are pressure-driven and can be integrated into existing drinking water installations.
• The adsorption performance depends, among other things, on the pH value of the raw water, the arsenic concentration and the contact time with the filter material.

Maintenance and operation:

• Regular analysis of the raw and purified water to check the arsenic concentration.li>
• Monitoring of the service life and capacity of the filter material
• Replacement of the filter granulate at specified intervals or when the limit value is exceeded
• Environmentally friendly disposal of the used material in accordance with the applicable regulations

Advantages of arsenic filtration with iron(III) hydroxide:

• Highly effective even at low arsenic concentrations
• No need to add chemicals
• Proven, practical technology with long operating experience
• Compliance with strict limit values in accordance with the German Drinking Water Ordinance (TrinkwV)

Areas of application:

• Private domestic water systems with arsenic-contaminated well water
• Small water suppliers in arsenic-contaminated regions
• Commercial and public institutions with their own water supply