You can't evaporate garbage -- greywater pre-filtering

[Tom.Jennings]

Mr. Polando's excellent evaporator at viewtopic.php?t=12911 works for clean greywater such as showers. But our relatively water-frugal camp's biggest wastewater source is kitchen washwater with lots of fats, soaps and food bits. It stinks, would be a nuisance in an evaporator without serious pre-processing.

So far we've been filtering, settling and for the cleaner stuff (selected rinse water etc) sprinkle-can on the road. The rest is hauled. We want to stop all of that this year, and our camp has doubled in size (duh, what else is new).

One new member, quite capable technically, is proceeding with testing a system of flocculation, large-area sand filtering and settling and bleaching, and is planning on producing water clean enough for recycling as wash water. Estimating 10 - 20 gallons a day capacity (we know that's small). My only worry is schedule. I'll update here with test results and such.

What are others using for this task? Or does everyone simply haul home? Ughh.

[Bob]

We just drink it straight... mix it with cooler water if you want it a little fizzy...

[skygod]

Flocculation Camp?
I stand in a garbage bag and pour water over my head, pour it in 5 gallon bottles and haul home.
And I was happy...
Now that I have read your post I want to flocculate.

[Thunder Monkey]

drain through a couple layers of cheese cloth, into a 5 gallon bucket or however big you need.

a sump in the 5 gallon bucket,

then an activated carbon filter after the pump. i would go with a larger one than the under the sink models. like .5 cubic feet to 1 cubic feet. this would have an incredible capacity for water to be filtered.

then you have not only reusable water, but you can drink it too. it would be cleaner than most tap water nationwide.

so you could theoretically provide drinking water as well as recycle gray water. AND IT WONT STINK EITHER!!!

ill talk it over further with some wastewater treatment and chemical engineers.

we could be onto something really righteous!!!

[nixiebunny]

I'm the guy that Tom was referring to. I live in Tucson, so it makes sense to me to use your grey water for evaporative cooling ,since you have to evaporate it anyways. I'm working on several things along those lines: A shower using our camper's outdoor shower head with hot and cold running water; a grey water filtration system that produces clean-smelling water; and a big evaporative cooler to both get rid of the water and cool off the camp members.

I have gotten about two-thirds done designing and building the first revision of everything. Not bad, considering I started designing it all ten days ago. I've had help from a couple good folks.

There are many 5 gallon buckets in the filter system, but the charcoal filter is a 5 foot long 3" ABS sewer pipe full of aquarium filter charcoal. The sand filter is a bucket with 50 lbs of play sand and a cloth screen top and bottom to keep the crud out and the sand in. It's all gravity fed, using pulleys and ropes to assist gravity where needed. No electricity is used in the filter.

The cooler is a big 6 foot square vertical panel that will use the breeze to evaporate water. CoolPad is the cellulose pad material I'm using. It's quite holy, so the air meets little resistance. A bilge pump with a float switch cycles water through the pad in an efficient pulsed manner, which I predict will work on 10 watts of solar power (I'm ever the optimist). If needed, the water recirculation rate can be reduced to conserve power at a cost of partially dry cooler pads.

I'm in the process of taking pictures of it all as I build it. I hope to post some soon to our camp's forum.

[Tom.Jennings]

drain through a couple layers of cheese cloth, into a 5 gallon bucket or however big you need.

a sump in the 5 gallon bucket,

then an activated carbon filter after the pump. i would go with a larger one than the under the sink models. like .5 cubic feet to 1 cubic feet. this would have an incredible capacity for water to be filtered.

then you have not only reusable water, but you can drink it too. it would be cleaner than most tap water nationwide.

so you could theoretically provide drinking water as well as recycle gray water. AND IT WONT STINK EITHER!!!

ill talk it over further with some wastewater treatment and chemical engineers.

we could be onto something really righteous!!!

Umm, have you done this already? Activated charcoal isn't magic; a gallon of soapy, oily water will clog it up, regardless of the molecular-square miles of area.

In the U.S., municipal tap water is spectacularly clean; I don't know where people get the idea that tap water is undrinkable (except from Coca Cola bottled water purveyors:

http://www.npr.org/blogs/news/2007/06/b ... _us_c.html



The reason I started this topic was, what with 5000 to 10,000 camps out there, small and large, people are doing SOMETHING with their greywater -- eg. "playa tested".

We're doing bulk filtering; this year we will attempt real flocculation (to get rid of gooey shit that plugs charcoal) followed by activated charcoal. (With the old system as backup :-)

Then we have to deal with disposal of the floc. Green is tough!

[Thunder Monkey]

[quote]Umm, have you done this already? Activated charcoal isn't magic; a gallon of soapy, oily water will clog it up, regardless of the molecular-square miles of area. [/quote]

not as described no i haven't.

i did however work for a water filtration company and we used a lot of activated carbon for many different applications.

the purpose of the cheese cloth would be to strain larger debris to keep it from clogging. this would effectively be just like using one of these.

[img]http://www.purewaterexpress.com/images/models/uvbb3.jpg[/img]

except for our purposes we don't need the filtration to go that far because we are using a large volume of activated charcoal which is cheaper and usually the last step in this process anyhow.

the charcoal is the consistency of gravel and it would take quite a bit to clog one of these. we are only using the filter itself for 1 week.

then you pump your given water into a tank like this.
[img]http://www.filterswater.com/water-purification/images/di-tank-diagram.gif[/img]

i would feel comfortable drinking water coming out of one of these tanks. mostly because i installed and exchanged these at safeway's and fred meyers across the pacific northwest on their produce misting systems.

you can believe me or not. thats up to you, but ill be happy to give you a beer and recycle some of your water for you next year.

=)

[unjonharley]

The water going into my kitchen sink at home is filterd before it hits the drain.. There is a wire mesh basket with a paper towel that all waters go through.. It picks up all food stuff that I dry in a bar b que rack.. The food stuff go's to the birds and paper to the worms.. I do not use dish soap.. Very hot water and a tooth brush the scald the dishes with boiling water..If I add oils (flax seed) to any food I wipe out each oiled dish/pan with a face tissue.. The worm like this waste paper also.. On the playa all this can be dryed and taken home as little the no weight or space.. This fall all my grey water will be going to water flower beds.. As a added step a person could put a 25$ in-line RV filler filter as a final step.. The water would be clean enough for bath..

AS for bath grey water: The japanees use a good system.. They dip water over then, then soap, then dip fresh water and final rinse in another location.. This way, only a small amounts of water is used to wet down, soap and pre rinse..

On the playa the main rinse can be filtered and possible reused.. While the per-waters go to evaperation.. leaving only the scum scabs and hair dryed to haul away..

I stand on a folded beach towel that stops most of the playa dust/mud from going into the waste water in the first place. Hang it up wet for the sun to deal with.. It will become crusty with playa dust.. so bring enough for each shower your planning on for the week.. Take your dry caked towels home, hang them on a drying rack, hose them off and throw em the washer.. but then again, a towels worth is all the water "I" need for a playa shower.. That's about one gallon..

So instead of all your filtering work.. Get all your campers on the same page in a new way to shower.. You will find some will want to bicer about it.. This may give you time to see the one s you don t need in your camp in the first place..

[Tom.Jennings]

The water going into my kitchen sink at home is filterd before it hits the drain.. . The water would be clean enough for bath..

!I bow before your deep thought and commitment!

That's pretty out there, you have my admiration. We try to be frugal here at home but we're Cheney and Bush compared to you.

On the playa the main rinse can be filtered and possible reused.. While the per-waters go to evaperation.. leaving only the scum scabs and hair dryed to haul away..

We've been doing a modest but similar method, of course the rinse water becomes the next wash water. The wash water got filtered (big funnel, paint filters and cheesecloth, into a 5 gal jug) and settled, and when clean enough sprinkle-canned onto the road. When our camp was 6 - 8 people that was "OK".

I stand on a folded beach towel that stops most of the playa dust/mud from going into the waste water in the first place..... but then again, a towels worth is all the water "I" need for a playa shower.. That's about one gallon..

I stand in a black plastic "mud tub" (used for stucco, etc) and wash off with a small bucket of water with dirty underpants. About a gallon also, and the tub of water just goes into the filter.

So instead of all your filtering work.. Get all your campers on the same page in a new way to shower..

You're right, minimizing "need" in the first place is best of all!

[current]

What is your strategy for floc? Kitchen water is exceptionally tough to deal with - we just haul it out. We have had reasonable success with shower water filtration (particulate, charcoal, UV) feeding an evap cooler. We did require use of castille soap and changed out the charcoal every 2-3 days. There are special oil absorbing charcoal media but the price is high. Bubbles in the cooler seemed a bit odd but were ultimately uneventful other than soapy smelling cool air. We managed to evaporate about 400 gallons this way in 2006, at a cost of well under one cubic foot of landfill material.

[Tom.Jennings]

What is your strategy for floc?

The plan is to settle it, separate and dry it, then haul it out. You are right, the kitchen stuff is nasty! Fats and soaps are the problem. Showers are easy. David was gonna test with home kitchen wash water, I forgot to ask him how that went.

Last year we had maybe 10 people; this year 20. I realize it's not a big camp, but we don't wanna wait for a big problem.

We're also bringing the simple filter and settling tank from last year, scaled up somewhat.

One C.F. of landfill, not bad! Congratulations!

[swampdog]

Don't know if it's etiquette to throw my plans into someone else's thread for comment. If it's rude, apologies in advance.

Here's my plan. Filter dishwater etc through a layer of screen-door material, then a layer of cloth, into a 32 gal trash can (raised up about 1 ft on blocks). I cut a drain hole in the trash can, and fitted (and sealed) a piece of garden hose in the drain hole. I'll attach a layer of paint strainer over the drain hose. The drain hose entrance is a little above the bottom of the trash can, so hopefully some of the nastiest stuff will settle below it.

From the drain hose, I've hooked up 200 ft of 1/2 inch black vinyl hose that I found for $15 at a local big chain hardware store. It's the stuff they use for automated drip sprinklers, for home or agriculture. I figure that's going to generate a fair bit of heat. Then I've got 20' of garden soaker hose. I figure by the time water drains thru all that it should be ready to hit the 12x6 foot evap pond.

There's another feed from the shower to another 200ft of 1/2 inch hose that Y connects into the soaker hose. Paint strainer also over the drain hose on the shower. Valves everywhere so I can control the flow.

I tested the main unit this afternoon. The only problem I had is that there wasn't enough water pressure to push the water from the reservoir (trashcan) through 200 ft of 1/2 inch hose. I haven't uncoiled the 1/2 inch hose (which I will do on the playa) so it may work better on the playa. I primed the 1/2 inch hose stack from the tap and it worked fine. Just to be safe, I got 2 of those pumps that you drive with a drill that I can use to prime the 200 ft of 1/2 in hose.

I'm hoping that the water spends very little time in the actual evap pond, it should very very hot by the time it gets there. I'll shut off the valves at night and reopen them when things start to get hot in the daytime (and prime if necessary)

Comments? Suggestions? This is for a camp of about 20.

Thanks!

[unjonharley]

swamp dog.. you got some thing going there.. mind if i swipe some of it.. not much water at my single camp.. the evap pond will be a oil drain pan (black plastic).. then a free standing camp fire grill.. hang sheets of paper towel from the grill to the bottom of the pan.. hold the paper with cloths pins.. the water wicks up the paper and the air carries it away.. if it s laying in a black hose to heat for a while all the better..

[swampdog]

is the sincerest form of flattery. Unjon, I'd be delighted to have my ideas copied.

[Tom.Jennings]

Don't know if it's etiquette to throw my plans into someone else's thread for comment. If it's rude, apologies in advance.

Rude!? It's rude NOT to! :-)

Filter dishwater etc through a layer of screen-door material, then a layer of cloth, into a 32 gal trash can (raised up about 1 ft on blocks). /.../ The drain hose entrance is a little above the bottom of the trash can, so hopefully some of the nastiest stuff will settle below it.

I wonder about the cloth... small pores plug up ASAP with fats and oils, the main problem with kitchen waste. Your idea for settling is good, but it really needs to be still to settle; as you add water is stirs the mess and un-does the settling.

Make sure you have enough capacity on the INLET side of your filtration system... my crude system uses a huge funnel with about 1 gal capacity. It can take many minutes for water to filter through. Our filter was simply cheesecloth and mesh fabric paint filters with elastic edges, both from the hardware store. It plugs up daily or more and we have to empty the filter into a trashbag,

From the drain hose, I've hooked up 200 ft of 1/2 inch black vinyl hose /.../ that's going to generate a fair bit of heat. Then I've got 20' of garden soaker hose. I figure by the time water drains thru all that it should be ready to hit the 12x6 foot evap pond.

I suspect your soaker hose will plug up (playa dust concretizing on the outside, oily goo on the inside) but it could work out great! In fact, water might not even make it to the other end, through evaporation!

The only problem I had is that there wasn't enough water pressure to push the water from the reservoir (trashcan) through 200 ft of 1/2 inch hose.

YEah, it's only tiny fraction of a PSI, and with soaker hose plugging even slightly, flow could stop altogether.

However gravity is "free" (yeah but you gotta lift the water up to use it)...!

Suggestions?

Yeah, but I'm filled with opinions, worth what you paid for them... test, test, test! Test with real dirty water, and bring a backup system! Everything goes wrong on the playa...! :-)

[Tom.Jennings]

...the evap pond will be a oil drain pan (black plastic).. then a free standing camp fire grill.. hang sheets of paper towel from the grill to the bottom of the pan.. hold the paper with cloths pins.....

I think you have a good idea... simple is good! Wet with water, the paper will be weak and heavy, and the ever-present wind will tear it and blow it around... use cloth!

Something like an old towel (terry cloth has lots of surface area), put a rock in the mud tub, drape the towel over it, put a rock on each side on the towel; variations on that theme are obvious... Dead simple, will work in wind, and you can repair it drunk :-)

[MrGod]

We have used a sand filter for the past few years for our kitchen waste water. It works really well.

Get a small trash can with a lid, cut a hole near the bottom and glue (silicone) in a pvc fitting that will take a 2-diameter flexible plastic hose. The hose drains into your evap pond.
Put about 4 inches of gravel in the bottom.
Next is a piece of window screen.
On top of that is sand - about 12 inches deep.
There should be about 6 inches of empty space between the top of the sand and the top of the can.
Put a removable window screen on the top of the can.
Drain your kitchen water into the sand filter. The top screen filters out the big chunks which you scrape off into your compost dryer.
The water that comes out the bottom of the filter is pretty clean. I got the idea from the way they do water treatment for drinking in the poorer parts of Africa. They say that the sand filter actually produces potable water but I'm not that trusting.
For sure we don't end up with a stinky evap pond when we use a sand filter
Come see ours at Amphibia this year.

The drawback is that it's really heavy. You have to take the can home, full of sand, and then dump it in the garden or something like that.

[Tom.Jennings]

We have used a sand filter for the past few years for our kitchen waste water. It works really well.

Oh my! Evidence that God really exists! Well, circumstantial, but I'll test later.


Wow, I would like to see this filter. It smacks of robustness and brutal, subtle, simplicity. Many good ideas seem obvious in hindsight :-)

[unjonharley]

wounder how foam would work.. lighter than sand..

some gravel to support wet foam off the bottom.. then a couple of sofa pillows cut to a tight fit.. maybe some thin slices for first filter.. they could be removed/replaced when soiled, dryed and taken home..

[capjbadger]

I'm surprised I haven't seen this here (perhaps I missed it)...

If grease and oils are such a problem, why not make a simple grease trap? Oils float...

Badger

[Tom.Jennings]

I'm surprised I haven't seen this here (perhaps I missed it)...

If grease and oils are such a problem, why not make a simple grease trap? Oils float...

Badger

Read the rest of the thread... The problem is oils etc emulsified with soaps. Try this simple experiment: fill a sink with soapy water. Scrape your dinner dishes free of big stuff. Wash in the sink. Scoop all the soapy, greasy, foody water into a bucket. Now try to separate the stuff from the water. That's the goal here.

It's tougher than it appears to pull off without a lot of energy or 'magic' (eg. "it just goes down the drain. It's magic!").

[capjbadger]

Read the rest of the thread... The problem is oils etc emulsified with soaps. Try this simple experiment: fill a sink with soapy water. Scrape your dinner dishes free of big stuff. Wash in the sink. Scoop all the soapy, greasy, foody water into a bucket. Now try to separate the stuff from the water. That's the goal here.

It's tougher than it appears to pull off without a lot of energy or 'magic' (eg. "it just goes down the drain. It's magic!").

I did read the rest. Must of missed that bit. *facepalm* Of course. Emulsified fats. duh. The whole point of soap... lol I'll have to play with this a bit.

Badger

[swampdog]

Great idea flash! Thanks, Mr. God! I've got a deep round tub that I'll bet will fit in the top of my 32 gal trash can water reservoir. I can make a sand filter in that tub that'll flow directly into the reservoir that'll mean my evaporator is just running clean water! Bet it'll work! I can't wait to get done pretending-to-work-but-thinking-about-burning-man to get to work on it!

If I get really enthusiastic I may even put a clear tube up the side to see how much water is in the tank and whether I need to run the pump or not.

[unjonharley]

gotta butt in here again..

after the gresse trap question.. I tryed my mesh basket/colander per- filter.. It held the grease and soap and seeped & wicked the water out..

i never buy paper towels.. but for the playa i am going with the supper "picker upper" towel.. sitting the colander in a larger pan with paper wicks.. this will be covered with a rabbit wire mesh so no moop occures.. also in the back of the cuboard there was a screen lid for frieing pans.. that will cover the colander in it s drying stage.. i use paper to wipe heavy food stuff from pans/dishes and throw the paper into the baskets..
this sopps up extra water and makes it easy to tansferr to the drying rack...

this could work for a small theme camp if they would use three baskets/colanders.. one for each meal along with a screen covered drying rack.. there is little or no odor if you dry every thing right away

[skibear]

Rube Goldberg would be proud.

I'll may even try some of this stuff; especially a sand filter
with prestrainer and bleach post filtering.
LOL

[Tom.Jennings]

gotta butt in here again..

after the gresse trap question.. I tryed my mesh basket/colander per- filter.. It held the grease and soap and seeped & wicked the water out..

I think your trick is good, but I worry at the scale. Only a control bucket of soapy water vs. a dusty sink of gooey dishwater on the playa. I don't mean to be negative! I just worry about my own shit staying intact 7 days in...

When you mentioned 'wicking' it occurred to me that another way to separate water from the rest -- while this won't scale AT ALL! is basically the capilliary action that drives chromatography. This isn't practical for playa use, but if you take a glass of water with stuff mixed in, insert a paper towel or something like it vertically standing in the water, stuff crawls up the paper to various heights,

http://en.wikipedia.org/wiki/Paper_chromatography

...where we would not be concerned with the analytes, just the solvent (water)!

I did this recently to see if anything was dissolved in a tank of old gasoline. (second photo down here http://wps.com/AMC/1963-Rambler-American/Gas-tank/).

I wonder how much surface area it would take to do a gallon a day?!


But anyhoo I digress, though it is fun to chat about ideas.

I was wondering with this thread, /what are people ACTUALLY DOING NOW on the playa/. I think that maybe there's not a lot of actual greywater processing going on, the few examples here are standouts.

[unjonharley]

\/
forgot to mention: i use a 2 quart garden sprayer for water pressure in the sink area.. it has the handle pump and nozze all in one..

also a little soap sprizzer and tooth brush for the tough stuff..
then wipe it out with paper and throw the paper in the colander..

I will build a complete evaperation sink for the playa.. come see me at 8:30 and F street.. we have an 18 inch bright orange trash fence around our camp..

reading all that hi teck shit will rot your mind.. this is from an old man that has time to watch water evaperate and wave as the world passes by..