Triple Water Filter System

About a year ago, I installed a triple water filtration system under my kitchen sink. My family used to go through a ton of water bottles each month. It drove me crazy. But I'm not crazy about drinking tap water, either. This seemed like a good solution. I have a question for anyone who might have researched this, though.



What to do with the spent filters?

I know they have contaminants trapped in the media. But some of them were neutralized by the charcoal filter, right? And the scale and lime are probably pretty inert, too.  But I worry about just tossing the spent filters into the trash, because they've probably got high concentrations of pharma runoff, pesticide/herbicide runoff, heavy metals, and all sorts of other gick. Is there a way to produce no waste with these? Any ideas would be helpful. I'm only on my second set, and I haven't thrown the spent set away yet.

j

Good Morning,

I work in filtration media production and I might be able to be of some assistance.

Water filtration tends to come in banks of filters, like what you have here with the three separate filters. This is because the filters themselves are constructed utilizing different materials in order to get you the clean water you so desire. Filters can be made from all sorts of base materials but usually is some combination of cellulose (tree), synthetic (plastics), and then generally some kind of chemical resin impregnation in order to increase the filters contaminant holding capacity as well as preserve its longevity before it breaks down. The material is usually pleated with some kind of wire mesh backer and put into the filter housing. Filters, unless branded, are not reusable and I would not recommend trying to clean them because you will do more harm than good. Carbon filters are very common because they are good at what they do and tend to be lower cost. This is generally followed by a pleated media filter to start capturing further contaminates that carbon filters don't mitigate.

The filtration space is dealing with the age old problem of cycle of life for their products because the end of life step is to send these to a landfill. In order to reduce the amount that gets sent there, you can look towards units that have high capacity filters that can be in service longer than other units. This however tends to come with a comparable cost increase. I'll peruse a few companies and see if I find what I'm talking about here I'll come back and repost an example.

Thanks, Timothy. I look forward to seeing what you find. I'm not against paying more for higher capacity, but in the end, it's all still ending up (mostly) in the garbage dump. But according to statistics, so is ALL of our plastic. The dirty little secret is that the amount of plastic actually recycled is statistically nearly insignificant. Chances are, even if your jurisdiction has you sort, or says they sort at the facility, they're sorted (or not) and go to the landfill anyway. Because nobody wants it. It is a monetary net loss endeavor.

With these filters, I'm relatively sure that two of the three would be relatively free of contaminants, and might be good candidates for cracking apart and maybe going into a reed-bed filtration system? Just thinking out loud here because I really don't want these in the dump.

Timothy Norton wrote:Good Morning,

I work in filtration media production and I might be able to be of some assistance.

Water filtration tends to come in banks of filters, like what you have here with the three separate filters. This is because the filters themselves are constructed utilizing different materials in order to get you the clean water you so desire. Filters can be made from all sorts of base materials but usually is some combination of cellulose (tree), synthetic (plastics), and then generally some kind of chemical resin impregnation in order to increase the filters contaminant holding capacity as well as preserve its longevity before it breaks down. The material is usually pleated with some kind of wire mesh backer and put into the filter housing. Filters, unless branded, are not reusable and I would not recommend trying to clean them because you will do more harm than good. Carbon filters are very common because they are good at what they do and tend to be lower cost. This is generally followed by a pleated media filter to start capturing further contaminates that carbon filters don't mitigate.

The filtration space is dealing with the age old problem of cycle of life for their products because the end of life step is to send these to a landfill. In order to reduce the amount that gets sent there, you can look towards units that have high capacity filters that can be in service longer than other units. This however tends to come with a comparable cost increase. I'll peruse a few companies and see if I find what I'm talking about here I'll come back and repost an example.

Without thinking too hard, is it possible to back flush any of these filters?

I'm having a hard time finding the exact literature for the brand of filters you have, but I would suspect that each filter serves a different purpose from the others.

Generally you would follow a process similar to this for triple filter systems.

Untreated Water -> Sediment Filter (Filter #1 grabs the big stuff) -> Carbon Filter (Filter #2 grabs smaller material/chemical/hardness ect ect) -> Polishing Filter (The finest media along with a focus on taste/smell) -> Out of Tap


I however have seen them where you have like two carbon filters with different pore sizes followed by a polishing filter.

The digging continues...

The need for various filtering efforts will depend on what contaminants are of concern. I think these can be categorized as: sediments (which can carry all of the following), biologics (various microorganisms), toxins (metals and organic compounds), and minerals (which may impart tastes and undesirable properties and some may also be toxic).

A 50 micron filter will remove a very high proportion of sediments and many biologics and it is inexpensive - a reasonable addition to any water use system, and absolutely essential before any other sort of filter simply to protect those other filters from being clogged unnecessarily.
Many biologics can be removed by a one-micron filter. giardia cysts and many bacteria are around one micron in size, and protozoa are larger, whereas viruses are smaller.
Some toxins are relatively low solubility so they tend to adhere to solids in the water - therefore, filters that remove particulate matter are also removing these toxins to a large extent. If toxins are a particularly great risk, then activated carbon is a more robust way to remove them. Some toxins are soluble and mechanical filtering cannot remove them.
Reverse osmosis is akin to filtering - the water passes through a membrane which is selective for the size of the molecule, and water molecules are very small. Almost all negative ions in water are larger, and positive ions cannot pass through a membrane without their negative brethren, so reverse osmosis provides a very high degree of purification. All viruses are far larger, as are virtually all toxins, and cannot pass a membrane IN GOOD CONDITION. However, membranes are very easily damaged by oils and by chlorine, and membrane damage can be difficult to detect in fresh-water systems.
Ion exchange can remove toxic metals and most minerals. It is not filtration, per se, but it is often considered in conjunction with filters because the ion exchange bed, like an activated carbon bed, is particulate and can trap sediments in addition to capturing the pollutants it is designed to capture. Ion exchange releases sodium ions in place of other positive ions which it captures.
Ultraviolet light, particularly in combination with an oxidizer such as ozone or hydrogen peroxide, is effective to destroy biologics and also destroy most organic toxins. The water should be pre-filtered so target pollutants can't "hide" in suspended solid particles and evade exposure to the UV light. UV lights are often expensive and require regular maintenance to keep the light path clear.

So, for many years I have used just a 50 um filter and a 1 um filter, because I do not have a high concern for toxins or minerals in rainwater - only sediments and some biologics - and that has worked well. If I had greater concern for biologics or for organic toxins, I would add UV-oxidation at the end. If I was totally paranoid, I'd eliminate the 1 um filter and add reverse osmosis. If I had high mineral content like from a clean deep well, I would not be worried about biologics or even toxins, but I might add ion exchange to get rid of the minerals. These are a few of the common schemes for water treatments.

I was an environmental consultant and designed water treatment systems once upon a time. I lived on a boat and had a reverse osmosis "water maker" for treating seawater to make drinking water. I have collected rainwater for drinking since 2001 - first on a boat, later on a farm, now in a house. So that is my creds. for saying this stuff, fwiw.

Filter #1 is a prefilter at 20microns, sadly its's most likely made from plastic.
Filter #2 and filter #3 is made from carbon, they trap alot of hydrocarbon toxins, and so I would add some oyster mushroom to it to break it down.

I don't think that your water has alot of heavy metals in it, so you could actually add them filter #2 and #3 to your land.