Waste Water/Effluent

[Dave Member Find all posts View Profile Close Dave]

Hi folks,

Im after detailed advice on the content of the waste water remaining after my water washing.

Im using methanol and KOH, and a prewash. After the prewash I am using bubble washing.

I am very concerned about what I do with this water as I am operating in a village in rural cambodia.

Directly beneath my site is a water table where the locals draw water from.
The area is also prone to flooding.

What exactly is in my wash water that I am pumping out.

What is best practice for me to deal with this wash water?

Nearby I have two concrete elevated tanks. Is it possible for me to use these to somehow recycle my wash water.

I really need some qualified advice on this, as I dont want to poison the locals.

Many thanks,

Dave

[Dave Member Find all posts View Profile Close Dave]

Re: Waste Water/Effluent

Hi folks,

Surely there is someone here who can advise me on the content of the water that comes from our biodiesel production...

Anyone?

Thanks!

Dave

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Waste Water/Effluent

The water will contain a small amount of soaps, a little caustic and possibly some biodiesel. If the biodiesel process was not of a high standard, the wash water may also contain some mono- and di- glycerides.

It is probably no more problematic than bath water. It is a lot less hazardous than sewage.

What do the residents of that area do with bath water, sewage, etc? This water can be disposed in the same manner.

How much wash water do you plan on using ?

[Dave Member Find all posts View Profile Close Dave]

Re: Waste Water/Effluent

The water will contain a small amount of soaps, a little caustic and possibly some biodiesel. If the biodiesel process was not of a high standard, the wash water may also contain some mono- and di- glycerides.

It is probably no more problematic than bath water. It is a lot less hazardous than sewage.

What do the residents of that area do with bath water, sewage, etc? This water can be disposed in the same manner.

How much wash water do you plan on using ?

Thanks for the reply Tony.

The locals are in a village environment, so going to the toilet is done in the trees. (which is not near the water source)

Water is gained from the 3 nearby old style hand pumps that are cemented in the ground.

Bathing is done by tipping water from buckets over themselves, and sometimes the women use soap and shampoos. This is usually done in homes nearby, again not near the pump.

Most homes are within 100-200 metres of the pumps, so I would assume all wash water being used by the villages is going into the same underground water basin that is feeding the water pumps (if indeed it goes into the water basin... the land here has a high clay content, so it may not even get that far).

My concern is that if I am making a lot of biodiesel, which I plan too, my wash water may put them at risk. While most people drink bottled water, some of the more hardened villagers have only ever drunk pump water,and are quite used to it.

I have been told that the wash water contains methanol, which will evaporate if its not contained to a small area. True or not?

You asked about how much water I plan on using. I am not sure about this, and need some advice, if you could...

Because I dont have a pressurised tap water supply, I am not using the spray method of washing. Im using a prewash, and then plan on bubble washing. I am unsure about how to go about the bubble washing though.

I have a 220 litre reaction tank, which feeds to a 750 litre settling tank, which feeds to a 750 wash tank. I have got a fish tank bubble with stones attached to a car battery.

How many litres of water do you recommend that I use for bubble washing? Do I need to do more than one bubble wash? And can I re-use the water from either the first, second, or both of the buibble washes for later batches?

What are other people doing with their waste water? Is anyone recycling it?

I hope that these two nearby outdoor cement storage tanks (open at the top) may be useful. Is there anyway I could pump my waste water in there and hope that soaps would separate or solidify,and I could easily use water from the top or the bottom for later washes?

Again, thanks for any advice!!

Dave

[Bio Popo Member Find all posts View Profile Close Bio Popo]

Re: Waste Water/Effluent

Hey Dave!
Cambodia eh? What's going on there?
During my research I came across material on recycling wash water. Apparently when you add water to the biodiesel an equilibrium is reached between the water and the biodiesel and the amount of soap and what not that the water can absorb. MEANING, that the 1st wash will have the most, and each progress wash will have less, SO, you could use the 2nd wash water again as 1st wash and a 3rd wash again as a 2nd wash. If you want to read the information for yourself, as I would bc I'm not 100% about it, go to another forum here http://biodiesel.infopop.cc/groupee/...rm/f/498605551
and search about recycling wash water.
Good luck dude!

Dave

[Sauman Senior Member Find all posts View Profile Close Sauman]

Re: Waste Water/Effluent

Hi Legend
Posted my thoughts on your personal mail.Not sure wether u got it.Server was playing up yesterday.
Hope it answered your questions.
Keep us all posted on the great stuff you are doing.
Folks we should be very proud as fellow citizens of good earth on what Dave has undertaken.
Dave I think when you get time elaborate a bit on the forum about the great stuff u are doing.All the best mate....we are there with you.

We can only do it together.....I call it a simple dream.......

Cheers

[Robert Administrator Find all posts View Profile Close Robert]

Re: Waste Water/Effluent

Yeah Dave, I echo Sauman's sentiments. I'd be happy to give you a bit of webspace if you wanted some room to host any photos or stories about what you are doing. Just PM me if you are interested.

Cheers,

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Waste Water/Effluent

Dave,
Have you considered methanol recovery as a simple cost reduction strategy?
Use a sealed drum for the byproduct, attached to a smaller drum in the shade, by a condensor. The bypriduct drum in the sun heats up the byprodict , causing methanol to evaporate. It passes thru the condensor and liquid methanol drips into the srum in the shade. Water cooling using a wet rag may assist, but all joints would need to be sealed to exclude air and moisture (I presume that the air has high humidity).

The biodiesel can also be allowed to settle for a month or more to allow the remaining byproduct and soaps to drop out as the methanol evaporates. There are reports that this is as good as washed biodiesel.

Have you considered using CNO as a diesel fuel without transesterification?

Tony

[Terry Syd Senior Member Find all posts View Profile Close Terry Syd]

Re: Waste Water/Effluent

Dave,

As Tony mentioned 'unwashed' biodiesel has a long history of use without harming an engine. The only problem that has been encounted is that glycerin can build up on the fuel filter.

You could let the unwashed biodiesel sit until the remaining glycerin drops out. It is the remaining methanol in the biodiesel that helps to keep the glycerin in solution, so it takes a fair bit of time.

However, since you are already doing a pre-wash, most (if not all) the methanol is being removed by the pre-wash. This means that the settling time will be reduced. Try taking a pre-washed batch of biodiesel and let it sit. It may only take a few days for the remaining glycerin to drop out. You will see a thin layer of darker fluid left in the bottom of the settling tank. Decant the top biodiesel and then throw the 'dregs' into the next batch of biodiesel during the pre-wash stage.

This technique will also avoid the production of the DWS that may occur in the later washes. You could then get away with making a biodiesel with a lower level of conversion. Since the climate you are in is rather warm, you may find that you won't have any viscosity problems with the lower conversion fuel.

Give it a go, you could save on the amount of methanol that you have to use in the esterification process, plus there is no wash water.

[Dave Member Find all posts View Profile Close Dave]

Re: Waste Water/Effluent

Thanks everyone for the kind words and great advice.

BIOPOPO, Im building a biodiesel plant in rural Cambodia, partially funded by an NGO (looking for extra funding to buy some bits and pieces if anyone has a few hundred $$ spare...).

The site is located at the country's largest rural university, which offers free education to students who normally wouldn't have the chance. The uni has limited power, with electricity being supplied at short intervals throughout the day (no power at night) by diesel generators.

As the school has limited funding, it relys on donations of diesel and money to supply the fuel for the generators.

My project aims to supply all of the uni's diesel needs, and produce some left overs to sell to put money back into the school, so we can offer more scholarships to rural Cambodians.

The project is also the first of its type in Cambodia and is attracting a lot of interest. Apart from the local interest that is being developed, the uni will also be teaching the technique to its agriculture students.

We are starting with converting used cooking oil (tough to find here, because everyone resells it), and are planting a Jatropha field that once at maturity will supply all the oil we need to operate the campus generators, and also add hours that we can supply electricity to the school.

I owe a great deal to Paul Martin from Melbourne, who kindly donated his time in training me on biodiesel production and continues to help me from abroad, and also to Sauman who has been very kind with sharing his experience and knowledge from abroad.

SAUMAN and ROBERT, thank you. Robert, Im in the process of getting a simple website designed to talk about the project and acknowledge contributors. I'd love a link, and anything else you can do to promote it. I'll have some pics of the plant in a few weeks. Thank you!

TERRY, thanks. I have a 750 litre settlng tank, and a 750 litre wash tank. I do 200 litre batches. Im worried that if I leave the unwashed product to settle for so long, instead of moving it on to my wash tank for washing, I will slow down my process... and have to wait longer before I can start processing my next batch. Im also really nervous about not washing the fuel. The generators we use at the Uni were donated and expensive. If I stuff up the generators, they will not get replaced and a lot of people will suffer.

TONY. Great advice. Thank you. Ive been wanting a simple solution for methanol recovery and the way you describe it, it sounds very suitable for my environment. Im am confused about the term "condenser". I dont know what one is or what it looks like. Being in Cambodia, things are hard to go shopping for..language barrier and market place... so Im not sure how I would go about finding one. Could you explain it more to me... perhaps the kind of places I could look for one, or can I make one myself? Cheers!

With regards to CNO, do you mean coconut oil? We dont have a lot available. However there has been a project running here that uses Jatropha oil without transesterification, and they have been generating electricity from old diesel engines for use in villages (recharging batteries and the like). They extract their own oil from Jatropha and got the oil tested.. the test came up OK. Still, havent seen any long term results on engine wear....

Cheers,

Dave

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Waste Water/Effluent

Dave,
Yes, CNO=Coconut Oil.

In a distillation process (eg methanol recovery), the liquid to be distilled is 'evaporated' from the liquid it is mixed with. In my example, I am suggesting solar heating of the drum containing the methanol.

The vapours are allowed to exit from the 'evaporator' and are cooled, so that the vapours condense back to a liquid. The 'condensor' can be as simple as a piece of copper pipe (air cooled), or it can be water cooled by running the copper in a coil thru a container of water. You could use a bucket with a hole in the bottom for the copper pipe to exit, sealed to contain the water.
You could (unlikewly) purchase a commercial condensor, or make one yourself from readily available copper pipe. Annealed copper pipe (soft) can be bent easily and normally comes in a coil, which could be either immersed in water, or just be kept in the shade. Depending on the effectiveness of the solar heating, greater of lesser cooling may be needed.
It is important to ensure that the evaporator, condensor and methanol receptacle are sealed to:
1. prevent loss of methanol, and
2. prevent water vapour diluting/contaminating the methanol.

I apologise if I wrote this at a 'low level', but to ensure that your understanding is complete, I felt the need to expalin as clearly as possible.

[Robert Administrator Find all posts View Profile Close Robert]

Re: Waste Water/Effluent

There's a recent thread on methanol recovery here as well.

[Bio Popo Member Find all posts View Profile Close Bio Popo]

Re: Waste Water/Effluent

Wow, great great stuff dave!! How did you get involved with this? It just sounds awesome, seriously, good on ya!

[Dave Member Find all posts View Profile Close Dave]

Re: Waste Water/Effluent

In a distillation process .....I apologise if I wrote this at a 'low level', but to ensure that your understanding is complete, I felt the need to expalin as clearly as possible.

That's great. Thank you! I've really wanted to do this but was unsure. This is something I can definitely do.

(No, I needed it dumbed down)