Tannin Removal Filter
What are Tannins?
Tannins in well waters form from humic acid, which is one of the major components of humic substances (or Natural Organic Matter (NOM). These are the dark brown constituents of soil organic matter. They can also be found in peat, coal, many upland streams and ocean water. Tannins are astringent, bitter-tasting plant polyphenols that bind and precipitate proteins. Tannins are natural organic materials that are usually the by-products of the natural break down of decaying vegetation and sometimes the product of “natures” fermentation process as opposed to the tannins found in wines.
Tannins are created as water passes through peaty soil and decaying vegetation. This causes the water to have a faint yellow to tea-like colour, and can cause yellow staining on fabrics, fixtures, china and laundry. Tannin may give an unpleasant aftertaste to water. It may also cause water to have a musty or earthy odour. Tannins are sometimes referred to as fulvic or humic acids and are more common in surface water supplies, lake or river sources and shallow wells than in deep wells. Water in marshy, low-lying, or coastal areas is also more susceptible to tannins.Automatic Backwashing Valves
What can I use to remove Tannins from my water?
Many filtration companies will recommend activated carbon filters to remove tannins. That is often not the correct solution, as tannins belong to a large group of complex organics with different properties . Common tannin treatment uses an organic scavenging anion exchange resin. The anion resin is sensitive to hardness, so some systems include a water softener as pre-treatment. The water softener extends the life of the anion resin and increases tannin absorption when the water is treated for hardness. If iron and manganese are present in the water we do not recommend a tannin removal filter. Anion exchange resin systems should be regenerated occasionally with a salt water solution to improve the effectiveness of the resin. Anion exchange resin systems can also change the chloride, alkalinity and sulphate levels of the water, so you may wish to monitor these substances more closely once the system is installed. Oxidation and filtration is another method to remove tannins, but is not as simple as anion exchange and softening.
At Pacific Water Technology we will analyse your water and recommend the best system for you. It should be noted that tannins can sometimes interfere with equipment used to treat other water problems. For example, the resins or medias in iron filters, cation exchange filters and neutralising filters can become coated by the tannins, and performance may be inhibited. It may be useful to test for tannins (using the “clear glass” method described above) before installing these types of water treatment devices.
Automated regeneration and backwash filters
Automatic Control Valves for backwashing Water Filters.
Pacific Water Technology supplies automated backwashing filters using a Clack Automated Control Valve. Backwashing Clack Automatic Control Valves are made to automatically backwash water filters and water softeners. Clack automatic valve are designed for residential, industrial and commercial applications with flow rates of up to 120 litres per minute, and backwash capability of servicing up to 64 inch diameter tanks requiring Inlet/Outlet fittings from 1″ to 3″.
The valves act as a primary centre that directs and regulates all cycles of water softening for filtration. They can be set to performs down-flow and up-flow regeneration or simply backwash and rinse. Clack valves are available in different program versions and are controlled by solid state microprocessors with front panel settings and screen display.
Fully automatic valves that provide efficient backwash cycles. The operation of the tannin filter is very similar to that of a water softener . Brine is also used for regeneration , however the frequency of regeneration and salt quantity can vary .
Features of control valves:
- Solid state microprocessor with easy access front panel settings
- Three modes of operation; meter immediate, meter delayed, or time clock
- Economical and simple to operate
- Calendar Override feature to ensure filtration media fresh and clean
- Double backwash feature offers efficiency, optimum regeneration and cleaning ability
- Stores system configuration and data in non-volatile memory
- Treated Water regenerate refill
- Down-flow and up-flow regeneration
- Low Salt Alarm
- Inlet and Outlet Fitting Connections from 1″ to 3″
- 12-volt output AC Adapter provides safe and easy installation
- Control valve design provides optimum service and backwash rates
- Reliable and proven DC drive
Filtration Media Description
These resins normally have a macroporous structure (though some gel scavenger resins do exist)
and they are normally manufactured from either polystyrenic or polyacrylic polymers. The Purolite
macroporous, polystyrenic based product is Purolite A502P and the macroporous, polyacrylic
based product is Purolite A860. In general terms the polyacrylic based resin often offers a greater
reversible removal of organics on regeneration (due to their more hydrophilic structure) and can
therefore often cope with a far higher level of dissolved organics. The polystyrenic resin can often reduce dissolved organics down to lower levels, but is less easy to regenerate (more hydrophobic
Due to their different structures and slightly different performance many modern plants now
include a combination of both these resins, with a 50:50 ratio employed. Using a bed containing
two different polymer structures frequently offers the best removal of organics.
In conventional co-flow regenerated plant the Purolite A502P is loaded first into the bottom of the
unit with the Purolite A860 on top. Some mixing will inevitably occur, but there is an advantage in
having the water passing through the polyacrylic resin first as this portion of the bed will see the
higher organic loading.
Expected dissolved organic removal rate : As outlined in the guidelines, the expected removal rate is 60 to 80% of the dissolved organics content, depending on the age of the resin and the efficiency of the regeneration. For brine only regeneration it is important to have significantly higher salt concentration – 250 – 300g NaCl/L of resin
A useful characteristic to calculate is the fouling potential or N factor.
The N factor of the water you are looking to treat, may give you an indication of the severity of the fouling present. Eg. what proportion of 8 is the N factor for your water.
Why Tannin Removal is Beneficial
Tannins are naturally occurring organic compounds found in plants, and they can make their way into our water sources through soil runoff or decaying vegetation. Although tannins are not harmful to our health, they can cause unpleasant taste and odor in our drinking water. This is where a tannin removal filter comes in handy.
A tannin removal filter is a water filtration system that effectively removes tannins from water, leaving you with clean and fresh-tasting water. Here are some of the benefits of using a tannin removal filter:
- Improved taste and odor: Tannins can give water an earthy or musty taste and odor that can be unappealing. A tannin removal filter can remove these compounds, leaving you with clean, refreshing water that tastes and smells great.
- Protection for appliances: Tannins can cause discoloration and staining in laundry, dishes, and fixtures, and can also damage appliances such as washing machines and dishwashers over time. By removing tannins from your water, a tannin removal filter can help protect your appliances and extend their lifespan.
- Better for your plumbing: Tannins can cause buildup in pipes and fixtures, which can lead to clogs and reduced water pressure. By removing tannins from your water, a tannin removal filter can help prevent these issues and keep your plumbing in good condition.
- Cost-effective: While there are other methods of removing tannins from water, such as reverse osmosis or ion exchange, these can be expensive and may require ongoing maintenance. A tannin removal filter, on the other hand, is a cost-effective solution that requires little maintenance and can provide you with clean, fresh-tasting water for years to come.
- Environmentally friendly: Using a tannin removal filter is a more environmentally friendly alternative to buying bottled water or using other methods of water treatment. By removing tannins from your water, you can reduce your carbon footprint and help protect the environment.
In conclusion, using a tannin removal filter is a great way to improve the taste and quality of your water while protecting your appliances and plumbing. It’s also a cost-effective and environmentally friendly solution that requires little maintenance. If you’re experiencing issues with tannins in your water, a tannin removal filter is definitely worth considering.