you want only to remove iron: in this case you mustto dose an oxidizer such as sodium hipoclrorito and then filter the water through a multimedia filter. I believe that this is the most economical solution.
b. You want to remove the iron and other salts: in this case the appropriate option is a RO equipment. The ideal is that the water is sent directly from the well to RO equipment, with the least possible contact with the oxygen of the air
An economical way of removing iron and other heavy metals is through the utilization of Activated Filter Media. This has been proven in research and independent testing by water utilities to produce 99% removal efficiencies down to 1 micron, >95% removal of Iron and significant reductions in chlorine usage and disinfection by-products (THMs).
The age old problem of iron in water is immediately remedied by the Aquathin Rust Sentry Iron Filter. For years, iron has caused deep, dark stain deposits in toilets, sinks, bathtubs, shower stalls, dishwashers, and icemakers. Only the frequent use of harsh acid-type chemicals and abrasive cleaners could reduce the stain deposits that would soon re-appear. The Aquathin Rust Sentry 2000 Iron Filter with it's powerful "potassium permanganate green sand filtering agent (KMnO4)", actively removes the iron and safely prevents staining. Often, the problem of iron is accompanied by dissolved manganese (blue-green or brown stains) and the rotten egg odor of hydrogen sulfide gasses. The Aquathin Rust Sentry 2000 iron Filter has the capabilities of removing these associated water problems while at the same time, acting on the iron. In areas where water contains decayed organic matter (humic acids or tannins) the Aquathin Rust Sentry 2000 Iron Filter is installed in conjunction with the Aquathin Soft & Clean Water Conditioner to prevent the shadow-type staining associated with tannins. Your Aquathin Professional Water Treatment Dealer is skilled in analyzing these situations in order to prescribe the correct system and installation settings.
2.63 mg/l will convert all the chlorine to chloramines which is poor at oxidizing Fe. The amount of cl2 required to break point chlorinate will be too expensive. While less cost effective a better strategy would be biological filtration with nitrification - denitrification and biological iron removal at the same time. The expensive part is getting enough dissolved oxygen to convert that much ammonia.
The most economical method will be aeration followed by sand filtration. If your pH is low you must introduce soda ash or caustic soda to increase water pH (to around 8).
First of all, it will be good to know what you are expecting as a result, in terms of treatment efficiency.
Second, if you want a really cheap system, you should use pH and oxygen levels to precipitate Fe3+ naturally. Then, you should also expect that other components will co-precipitate with it, reducing turbidity and Mn.
If you want a cheap treatment and you have space for the treatment system, I would propose a 3 step treatment : 1° adding air and ajusting the water quality + 2° precipitation chamber + 3° nitrifying and biological stabilization.
Aeration provides the oxygen necessary to change Fe++ into Fe+++ which is colloidal. The filtration (sand filters) after that removes the colloidal Fe+++. The best efficiency is achieved by spraying the water into a drum full of air (contact surface is enhanced). Some working pressure above atmospheric improves the solubility of air and the efficiency. The consumption of air is rather limited and therefore the compressed air make-up is not costly, but some air blow-down is recommended because the solubility of O2 is higher than N2 and the gas composition may become enriched by N2 after the preferential dissolution of O2 into the liquid phase
Hi Thisara, you may need to modify the pH with the application of aeration. Higher pH (>6.5) will improve oxidation of iron. The floc formed by the oxidation of iron may be sufficient to coagulate the turbidity, but you may also need to add an additional flocculant as it looks a bit low. Ammonia can be removed with clinoptillolite - a natural zeolite that is normally quite cheap. Place a layer on your filters or a dedicated exchange column. You may also want to try to identify where the ammonia is coming from (e.g. fertilizers, cattle pens, on-site sanitation) and then try to manage these to reduce the ammonia in the longer term. The manganese is quite low, andnwill precipitate out with higher pH.
We use an iron and manganese contactor to remove these constituents from the water. Iron and manganese comes out of solution from the water as precipitate and is filtered out of the water through injection of chlorine.
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by Samuel DeGuzman, Water Treatment Plant Supervisor