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Filtering shower water

Filtering shower water

Filtering shower water


I am currently working on a small project for dry cabins in Alaska without running water. The cabin is heated using a wood stove, so I am using that to heat the shower water. I want to use a closed loop shower system where I can filter the shower water after use and keep reusing it for a week or month period. Is there an economical way to filter the soap from the shower water??

This is my first post, so please redirect me if I am in the wrong sub.

Thank you

RE: Filtering shower water

Are you going to use the shower after the month of recycling? When city folk see a drain and the outhouse in 50 feet away at 3:00AM, guess what they will do.

Richard A. Cornelius, P.E.

RE: Filtering shower water

That's not likely feasible. Shower water is not even greywater as it has feces in it. It could be done but the tech, energy, and maintenance would be bigger than drilling a thousand foot well or running a pipe over hill-an-dale or somehow doing a catchment/cistern system.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Filtering shower water

Yes, it is possible to recycle the water. No filter will work as the soap is dissolved in the water, not a particulate.

You would have to use a prefilter, then Reverse Osmosis, then UV to disinfect the water. Probably would cost over $10,000 for the equipment and you probably will not be able to afford the operating costs. There will significant power requirement to operate it which is a problem out in the woods. The RO will also waste 20-30% of the wastewater as well.

You can recycle the shower water as grey water for use in the toilets. That is an easier proposition.

RE: Filtering shower water

Would think soap is the least of your worries, how do you plan to remove the body oils, urine and other nasties that will be present in the shower discharge. bimr has summarised it extremely well for you as a non event.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

RE: Filtering shower water

Thanks for the reply's. I am looking into nano filters and an activated carbon filter to filter out bacteria and body secretions. I also think UV lights could be easily used to kill bacteria. Chlorine could also be used to kill bacteria too. This project is very preliminary, but two companies are already filtering shower water with 90% efficiency (https://orbital-systems.com/about-us/). The considerations would be the pressure drop in the filtration system and how often the filters need to changed.

RE: Filtering shower water

There are more considerations than that. Besides the mundane aspects of water such as dissolved salts, there are public health aspects such as contagious diseases.

The wastewater market has annual sales of around $200 billion US. If water recycling was such a simple problem, recycling of shower water would already have been solved.

My understanding is that the orbital system has never made it into production. The orbital "inventor" as he has been described is an industrial designer. The water recycling problem is not something that can be solved by a designer with no experience in water treatment. The orbital video does shows the filter cartridges but does not show a pump. The installation also shows a 400V 15 amp power supply is necessary. Most houses do not have 400V power available.

Orbital compares a water shower to the space station. The space station crew does not use a water shower. See the attached article on the complex water recycling system that is installed on the space station. The design of the water recycling system in the space station is also still under development. The comparison to the space station is misleading.

At this point, the orbital concept is just smoke and mirrors.

One reviewer calls it "crazy".


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