In this article we look at how iron affects water quality and the different methods available for removing iron from groundwater. Iron, which is naturally present in rock and soil, is easily dissolved in water. As a result of this, water sourced from boreholes, otherwise known as groundwater can have excess iron present.
Iron in Groundwater
When groundwater contains oxidised iron it is often evident due to the certain brownish colour present, however, it commonly exists as dissolved ferrous compounds and in this state the presence of iron does not colour the water. To remove dissolved iron from water it is usually necessary to oxidise the ferrous iron, by means of an aeration process, followed by a filtration stage.
When iron is present combined with organic matter and in a stable form, the removal process in this instance will typically involve coagulation. A strong oxidising agent such as chlorine, will also be required for this process, although this presents a further challenge with the need to remove chlorine prior to public supply.
With a variety of methods suiting different scenarios it may be difficult to establish the best solution for a given project. There is a need to consider the cost of initial set-up, ongoing operational costs and the specific demands and uses of each site. For example, occasionally a bore hole or well might produce good quality water on a normal day-to-day basis, however there might be instances where variations due to pumps starting and stopping, and variations in flow rates that could bring up iron from the ground and reduce the water quality requiring an on demand bespoke solution.
Amazon Filters can help reduce costs by providing expertise in solution development, in-house bespoke manufacturing and direct filter supply.
Amazon Filters’ R31 Filtration Solution
If iron removal is required for drinking water, Amazon Filters have designed a filtration solution which is DWI R31 compliant. Our SupaSpun II filters can be used in the filtration of ferric state iron and we can support on-site trials using different filters to establish the most cost effective and long-lasting filters for purpose. In these instances, we work alongside the site team to monitor the filtration process and water quality developing the best solution.
Amazon Filters’ SupaSpun II filters have been trialled and tested for the effective removal of iron from borehole water destined for public drinking water supply. The SupaSpun II filters have proved highly effective for daily demand of 20 MLD (millions of litres per day, with reference to municipal water), and up to 68 MLD during emergency water supply.
Other benefits of using Amazon Filters’ SupaSpun II filtration solutions for drinking water include:
- Fast availability with quick installation times (skids are delivered ready to go). If, Media Beds are being looked into these can have very long lead times and cost around ten times as much as Amazon Filters’ cartridge solution.
- Filtration cartridges do not require flushing prior to use and can therefore be brought into full service as soon as they are installed.
- The filtration system can be run intermittently or when water quality issues arise, resulting in an increase in the life of the filters.
- Amazon Filters offers onsite support and collaboration to derive the best out of the filters.
Regulation 31 requires that products used in the production of potable water for public supply must be listed on the Secretary of State’s list of approved products and Amazon Filters’ R31 SupaSpun II filters are on this list.
We also offer flexibility and onsite assistance, offering support to contractors and water companies to establish the optimum running and most cost-effective solution which will suit your budget requirements and the requirements of the site.