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There are a few ways you can collect and store your reverse osmosis waste water in order to be reused or repurposed, and some methods are definitely easier than others!
Before we delve into it, though, an important thing to note is to be aware of what contaminants may be lurking in your waste water. If certain pollutants are in concentrated amounts, they may not be suitable for specific purposes (for example, too much sodium won’t be ideal for watering plants).
Now that that’s out of the way, let’s look at how you can collect and store your RO waste water!
There are several ways you could collect and store your reverse osmosis waste water for alternate uses (depending on what’s in it, of course!) But the easiest way is to use a reject water tank…
The simplest way to collect your RO waste water is to reroute the waste water line from the drain pipe to a reject water tank. Ideally, this tank should be large enough that you aren’t running to empty it five times a day, but any tank or bucket that won’t overflow would do.
Remember that your RO system may produce a lot of waste water, depending on the model you have and various other factors. For under sink units, it could be 3 to 5 gallons for every gallon of water you use. If you only have a gallon bucket, then it will end up full way too quickly to be convenient.
If you have some DIY experience or someone willing to help, it is possible to run the waste water drain line directly to your washer and utilize the RO waste water for washing clothing. This is only recommended if you do not have any discoloration in the waste water that could stain your clothing, though.
It is possible to connect your RO waste water drain tube to your toilet cistern so that you are using waste water when you flush your toilet rather than your regular household water. This would likely require the assistance of a plumber to run the lines to the bathroom.
You could also run your RO waste water line directly outside to your garden or planter boxes, provided that the plants you have there are okay with the level and type of dissolved solids in the water. You would also need to make sure the plants were not the kind to easily succumb to overwatering.
Eventually, the RO waste water will end up at a water treatment plant, where it will be filtered and recycled.
You can use your RO waste water around the home in several different ways.
The amount of water a reverse osmosis filter system will likely waste depends on numerous factors. The main one is the model you have, as some models are simply more efficient than others.
It is possible for your RO system to waste 5 gallons of water for every 1 gallon filtered, all the way to only a quarter gallon of water for every gallon filtered. Check with the manufacturer before purchasing to see what the estimated waste water ratio of your machine might be. This may be described as the system’s ‘recovery rate’, which means the percentage of purified water produced.
So, why do RO systems waste water at all? Simply put, it needs to in order to function effectively. If it did not, filtration would be incredibly slow and contaminants would build up on the reverse osmosis membrane and clog it. RO membranes are flushed with water as they filter to dislodge any stuck contaminants and ensure they are sent down the waste water drain.
There are easy ways to reduce the waste water output of your reverse osmosis system and thus increase its recovery rate:
If you have any questions about RO waste water collection please don’t hesitate to leave a comment below!
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