Dishwasher but no septic

I didn't know that dishwashers are not recommended to be used in greywater systems because the dish soaps are too harsh. I've ordered Art Ludwig's New Oasis Design greywater book. I'm planning on only having greywater, no septic due to cost. I will have a composting toilet. I want a dishwasher, I like to cook with pots and pans and don't like banging them around in the sink. The house is a tiny so the counter is only 24" deep so not a very big sink. Please don't try to talk me out of the dishwasher by telling me how you enjoy washing dishes, I don't. Therefore, is there some low tech way to filter the dishwasher water so that it will be okay for greywater? Or, maybe I should just have a sacrifice area and not worry what it kills, I've got a lot of acreage to spare. Though downhill of the house is what used to be a (seasonal?) spring which was probably ruined by gas pipelines, a small dam, and the livestock feeding area all above it.
Also how might I recover some of the heat from the dishwasher and the bathtub? The tiny is a shipping container (8'x20') which will be on piers. I haven't decided how high off the ground it will be. I'm in Western Oklahoma where the wind comes blasting down the plain in winter, brrrrr.

Don't have any experience with them, but have run across dishwasher soaps claiming to be greywater safe. Big problem with most of them are high levels of sodium or boron, which will absolutely nuke the soil. You won't be able to filter them out, and honestly, even just trying to inflitrate them probably won't work well since there won't be the life in the soil to break down the fats from the dishwasher, so you'll stop infiltrating into the soil. Wish I had a good suggestion for you...


As for capturing heat, easiest way to capture heat from a bathtub is to not drain it until the water is cold. Heat (and a bit of humidity) ends up going into the house

Kitchen sink water is considered black water because of the food particles and gunk that comes with it. I have seen pre-filters or grease traps before the greywater distribution. It will require cleaning. With that being said it will be stinky.

I am working through this issue myself.  Done a fair bit of research into earthships dealing with this.  First, they have a tempering cell--a small cell to release the heat back to the house and prevent cooking the main greywater cell biology.  The kitchen sink cell has red wigglers and bananas to deal with the grease and nutrient in the water.  I am going to add some saltwater marsh plants to deal with the dishwasher detergents, while using the greenest soaps we can find/make.  

I will be doing this in an earthship-esque live-in greenhouse that will (hopefully) be subtropical or better in the winter.  You will need to figure out what to do in the winter.  I highly suggest a small greenhouse that can stay above freezing so you can filter the water year round.  

A grease trap will remove solids, oils and fats to a great extent.
Some traps have removable baskets which are easier to keep clean. But it is a rotten job.

A reed bed sealed with suitable lining may be an option.
That bed would need plants that love what you plan to feed it and the lining will prevent contamination of the surrounding areas.
These beds rely on the plants transpiring the fluid.

Here is a book I know of;
Reed bed book downloadable

I agree that the detergent is the biggest issue -- it's pretty nasty stuff. But I wonder if it has to be specifically dishwasher soap to work, as long as it's  a non-foaming soap. I wonder if there are bio-friendly soaps for the HE front loading washing machines that would do the job?

I ran a dishwasher with a greywater system for 4 years without an issue.  If course, I was careful regarding the kind of soap.

I also ran a dishwasher with a greywater system and it was fine. We had composting toilets and everything else drained to a large indoor greywater bed planted with fig and banana trees and various perennial houseplants. This ran without any fuss for the 9 years we lived there. I tried various options for the dishwasher including soapnuts and homemade recipes and finally settled on an eco friendly commercial product. Can't recall which, unfortunately. We have always been very careful about what goes down the sink so no oils etc. Started out with homemade laundry powder and ended up with soapnuts. Used soapnut liquid for hand washing dishes when needed and for most general cleaning around the house.

Very interesting. What do you look for in a dishwasher soap?

I know the stuff we've been using works very well, in part because it's corrosive and bleachy. I wouldn't put the effluent on my vegetables, but with good dilution would pump it onto a long row of shelterbelt trees with good, living soil to break things down.

Permies is such a great forum.

John F Dean and Andrea Locke, it's great to hear you both ran a dishwasher for so long with no problems. Andrea, did you eat the figs and bananas? What climate were you each in? I already make soapnut laundry detergent. Any idea what I want to avoid in my dishwasher soap?

I didn't think about indoor reed beds. I don't really want to be tied down all year round so not sure if that would work with me gone for months at a time. Do you know?

John C Daley, The Reed Bed book is $97AU. Do you highly recommend it?!

Cheers!!

Hi Douglas,
I was really just looking for something reasonably 'green' that also got the dishes clean...some of my earlier experiments weren't great at cleaning. I also often added a glug of white vinegar which seemed to help. Water was pretty hard.

I never grew food in the greywater bed so no doubt would have researched this more carefully if I had intended the water for food garden irrigation.

Hi Denise,
I was in zone 4. The figs only ever flowered once but never produced and the banana was an ornamental variety. I planted the bed quite densely with a variety of 'understorey' plants - cannas, zebra vine, ferns, sanseveria, christmas cactus, hoyas, etc.
The setup was inside the large kitchen we added on to the house. We had a large south facing wall of windows and the greywater bed was U-shape with the long bottom along those windows. My husband figured out the roof overhang so we got lots of sun in winter but only indirect light in summer. The ceiling was about 12 feet at the peak and the bed was from floor to about waist height so the trees in the middle of the bed had a maximum of 8 or 9 feet to grow up, a couple feet less than that at the outer edges. From front to back the bed was about 4 feet. We lined it with fiberglass car body stuff - the fabric and the goo - fortunately before we moved in as it took a while to air the place out. I don't know if I would use that again but am not sure what would be a greener alternative. As this was in a kitchen we wanted it watertight. The floor was concrete (or cement?) sorry I always get those mixed up. Which was good to have a floor that didn't mind being wet as we did overflow the top a couple of times - needed to remember not to do marathon laundry sessions as the plants couldn't keep up with it. The fiberglass was inside a wooden box with tongue and groove cedar so it didn't mind getting wet either.

Hi Denise,

We used a local mix of soap that was sold at the local cooperative. I doubt if either the soap or the co-OP still exists

Hi Denise:

FWIW - I have a dishwasher on a greywater system and haven't had any problems.  I'm using Palmolive eco+ detergent, it's reasonably priced and should be locally available.
Research the ingredients for peace of mind, but says phosphate free and "friendly to lakes and streams" ....that last bit may be a bit of a stretch, in my opinion.

Also perports that it "dissolves 24hr stuck on food", I'm not so sure about that, either. I usually hand wash tough stuck on foods (ie: egg yolk) and use the dishwasher for the finish wash.

As far as reclaiming heat from the dishwasher wastewater, I would probably advise against that. My take is that it's best to keep the greywater hot so that any dissolved grease doesn't solidify and clog your pipes.
Perhaps a better solution can be found (ie: a grease trap), but not sure it worth the potential heachache.

-Pete

Came here to ask pretty much the same thing! We have a sink and dishwasher hooked up to empty into a future banana plant area. I’ve seen recipes for creating one’s own Castile soap detergents, as well as recipes for using Castile soap sprays on plants without harm, so I’m assuming it would be safe for the garden area? If anyone has any input, that would be much appreciated, thanks!

yup, same problem. I've been hand washing with Dr. Bonner's but after 13 years I'm just tired of standing there in front of the sink like it's 1870! I've got a million other things that need to get done! So the biggest problem with dishwasher detergents (typically) are the salts. Even the super duper eco friendly ones are saturated with salt and sodium. (even Oasis)  DIY versions also include salt. I came across one post somewhere where they used Dr. Bonner's, water, vinegar in equal measurements and lemon juice. (I think it was a teaspoon for every half cup of the soap) then she added vinegar to the rinse aid receptacle. But I can't find anyone who has reported on the effectiveness of this diy. Maybe I'll mix up a batch and go test on family members dishwashers. I have zero interest in buying a dishwasher, only to find out it was pointless.
Okay, just had a thought - a dumb thought - but a thought all the same. A vertical rack and a heated pressure washer just blast it on either side. Boom! Done! (mic drop and walks out of the room)

yup, same problem. I've been hand washing with Dr. Bonner's but after 13 years I'm just tired of standing there in front of the sink like it's 1870! I've got a million other things that need to get done! So the biggest problem with dishwasher detergents (typically) are the salts. Even the super duper eco friendly ones are saturated with salt and sodium. (even Oasis)  DIY versions also include salt. I came across one post somewhere where they used Dr. Bonner's, water, vinegar in equal measurements and lemon juice. (I think it was a teaspoon for every half cup of the soap) then she added vinegar to the rinse aid receptacle. But I can't find anyone who has reported on the effectiveness of this diy. Maybe I'll mix up a batch and go test on family members dishwashers. I have zero interest in buying a dishwasher, only to find out it was pointless.
Okay, just had a thought - a dumb thought - but a thought all the same. A vertical rack and a heated pressure washer just blast it on either side. Boom! Done! (mic drop and walks out of the room)