What you think of my watersystem?

[FvH]

Hi everybody,

The land is in the hills not far from Chiang Mai

There is a well and i was looking for the right way to use it

I searched the net for info and designed a watersystem with 4 tanks

Please look the attached file, any suggestions

appreciated

Frans

Edited May 9, 2015 by FvH

[dragonfly94]

i see no file

[FvH]

Sorry, my first post

The image is there now

[canuckamuck]

You need to workout a backwash system.

I did a tank with sand and stone and then a reservoir tank behind it. when I want I can turn a valve and water from the house pump enters the outlet of tank 1 and forces the dirt out of the sand and then pours out an overflow that I can open just above the sand layer.

If I don't backwash every few months the water flow through the sand is reduced to a trickle.

Edit: I forgot to mention that my system is from a spring fed stream, so I get some muddy water days (not muddy at the tap though) especially in rainy season. So I would need to back wash much more often then a well sourced system.

Edited May 9, 2015 by canuckamuck

[Crossy]

Those are pretty large filters, what sort of daily water volume are you thinking of?

Have you had the water tested? It's useful to know what you need to remove other than the usual crunchy bits.

What use will the final water be put to, flushing and showering or drinking too?

[sappersrest]

Are the tanks going to be made out of concrete rings, or fabricated from s/s and will you have sealed lids on the tank, if you like pm me with more info.The filter tanks seem extremely large, it would seem that at a filtration rate of 10 cubic metres an hour per sq m of filter that filter should cope with approx 8000 litres per hour and of course if the target filtration rate was reduced then the final result would be a filter capable of half that amount and so on.

For that large scale of filtration the slower the filtration rate the better the water quality.One presumes it is for a large resort?

I would recommend the sand filter should be at least 1m deep and remember as previously stated a back wash system should be considered,also the carbon should be on a small bed of sand to support it.

As i said pm me if you require more info.

[FvH]

You need to workout a backwash system.

I did a tank with sand and stone and then a reservoir tank behind it. when I want I can turn a valve and water from the house pump enters the outlet of tank 1 and forces the dirt out of the sand and then pours out an overflow that I can open just above the sand layer.

If I don't backwash every few months the water flow through the sand is reduced to a trickle.

Edit: I forgot to mention that my system is from a spring fed stream, so I get some muddy water days (not muddy at the tap though) especially in rainy season. So I would need to back wash much more often then a well sourced system.

Like i point out in the image:

for cleaning tank 1 open valve X1 and wait til the water that come out is clean

for tank 2, open valve X2 and stirring a bit over the sand til the water come out clean

for tank 3, wich is just for bacterial cleaning, replace the charcoal every, what? 2 years?

The well have quite clean water

[FvH]

Those are pretty large filters, what sort of daily water volume are you thinking of?

Have you had the water tested? It's useful to know what you need to remove other than the usual crunchy bits.

What use will the final water be put to, flushing and showering or drinking too?

yeah, big tanks, almost 2 cubic meters a piece

at the end of the dry season there is not much groundwater left in the hills, so some extra can be usefull

The water is clear and even taste good, after the stone filter and then the sand filter we have the charcoal filter for bacteria removel

I might test this water to be sure, and maybe can use as drinking water as well

[FvH]

Are the tanks going to be made out of concrete rings, or fabricated from s/s and will you have sealed lids on the tank, if you like pm me with more info.The filter tanks seem extremely large, it would seem that at a filtration rate of 10 cubic metres an hour per sq m of filter that filter should cope with approx 8000 litres per hour and of course if the target filtration rate was reduced then the final result would be a filter capable of half that amount and so on.

For that large scale of filtration the slower the filtration rate the better the water quality.One presumes it is for a large resort?

I would recommend the sand filter should be at least 1m deep and remember as previously stated a back wash system should be considered,also the carbon should be on a small bed of sand to support it.

As i said pm me if you require more info.

The tanks are already built, just finished last week, and yes, concrete rings, 1m round 40cm high, 6 per tank, all sealed

Before i do the piping, i made this post to see if i got it all right.

I don't know yet about sealed lids, i have the idea to let them breath, maybe some mesh

It might seem all that large but it is storage at the same time

The whole thing is for just my house, and if it have slow filtration, the better

See for the bachwash my earlier comment

the sand and carbon are on stones, is that ok?

thanks for reply

[sappersrest]

Slow filtration is always best, However to successfully back wash the filter you do need to back wash at a a rate of 25-30 cubic meters per hour per meter sq of filter to properly fluidise the filter bed and clean the filter properly, you should look to use your well pump to achieve this.

[Crossy]

Charcoal does NOT remove bacteria. It does however remove many dissolved chemicals.

A UV and / or RO system (or a very fine ceramic) is needed to remove the wildlife.

With gravity feed you're never going to get tank one less than 80% full, tanks 2 & 3 about 60% and the final tank empty.

It may be an idea (if you really need to use the last drop) to plumb the drain points together so you can balance the tanks without filtering if you are short of water.

[canuckamuck]

Are the tanks going to be made out of concrete rings, or fabricated from s/s and will you have sealed lids on the tank, if you like pm me with more info.The filter tanks seem extremely large, it would seem that at a filtration rate of 10 cubic metres an hour per sq m of filter that filter should cope with approx 8000 litres per hour and of course if the target filtration rate was reduced then the final result would be a filter capable of half that amount and so on.

For that large scale of filtration the slower the filtration rate the better the water quality.One presumes it is for a large resort?

I would recommend the sand filter should be at least 1m deep and remember as previously stated a back wash system should be considered,also the carbon should be on a small bed of sand to support it.

As i said pm me if you require more info.

The tanks are already built, just finished last week, and yes, concrete rings, 1m round 40cm high, 6 per tank, all sealed

Before i do the piping, i made this post to see if i got it all right.

I don't know yet about sealed lids, i have the idea to let them breath, maybe some mesh

It might seem all that large but it is storage at the same time

The whole thing is for just my house, and if it have slow filtration, the better

See for the bachwash my earlier comment

the sand and carbon are on stones, is that ok?

thanks for reply

The size of the tanks won't be a problem. The bigger the tank the slower the movement of the water. Water moves slower through a big pipe than a small one when the same pump is used. That's velocity not volume of course.

Lids are a good idea, they don't necessarily need to be sealed, but you should try to keep the light out to discourage algae and algae loving critters. Also it is good to keep out frogs and lizards and leaves and other stuff that blows around.

For the backwash I know you have it figured that you can just open the tap and the dirt will come out. but if you do not reverse the water flow, most of the dirt will stay right where it got stuck. Backwashing is the proven method of cleaning sand filters.

If I have time tomorrow I will try to draw up a workaround for you.

[worgeordie]

Or you could use Ozone,

regards worgeordie

[FvH]

Charcoal does NOT remove bacteria. It does however remove many dissolved chemicals.

A UV and / or RO system (or a very fine ceramic) is needed to remove the wildlife.

With gravity feed you're never going to get tank one less than 80% full, tanks 2 & 3 about 60% and the final tank empty.

It may be an idea (if you really need to use the last drop) to plumb the drain points together so you can balance the tanks without filtering if you are short of water.

Thanks for the info

But i not agree with your %s, tank 1 will be filled till the sensor on top unless the sensor in the well shut off regarding the waterlevel in the well.

Your'e right that tank1 have to be 80% full before the other tanks will be filled.

If tank 1 is 90% full, up until the sensor, all tanks will be 90% full, there is no other way

Maybe i lower the connection between tank 1 and 2 to speed up the process

[FvH]

Are the tanks going to be made out of concrete rings, or fabricated from s/s and will you have sealed lids on the tank, if you like pm me with more info.The filter tanks seem extremely large, it would seem that at a filtration rate of 10 cubic metres an hour per sq m of filter that filter should cope with approx 8000 litres per hour and of course if the target filtration rate was reduced then the final result would be a filter capable of half that amount and so on.

For that large scale of filtration the slower the filtration rate the better the water quality.One presumes it is for a large resort?

I would recommend the sand filter should be at least 1m deep and remember as previously stated a back wash system should be considered,also the carbon should be on a small bed of sand to support it.

As i said pm me if you require more info.

The tanks are already built, just finished last week, and yes, concrete rings, 1m round 40cm high, 6 per tank, all sealed

Before i do the piping, i made this post to see if i got it all right.

I don't know yet about sealed lids, i have the idea to let them breath, maybe some mesh

It might seem all that large but it is storage at the same time

The whole thing is for just my house, and if it have slow filtration, the better

See for the bachwash my earlier comment

the sand and carbon are on stones, is that ok?

thanks for reply

The size of the tanks won't be a problem. The bigger the tank the slower the movement of the water. Water moves slower through a big pipe than a small one when the same pump is used. That's velocity not volume of course.

Lids are a good idea, they don't necessarily need to be sealed, but you should try to keep the light out to discourage algae and algae loving critters. Also it is good to keep out frogs and lizards and leaves and other stuff that blows around.

For the backwash I know you have it figured that you can just open the tap and the dirt will come out. but if you do not reverse the water flow, most of the dirt will stay right where it got stuck. Backwashing is the proven method of cleaning sand filters.

If I have time tomorrow I will try to draw up a workaround for you.

Yes, they have to be covered

For the backwash, i can connect from the house pump to the lower valve on tank2, close the valve from tank1 and open valve X2. Should be no problem

[FvH]

Or you could use Ozone,

regards worgeordie

Well, the whole idea is to make it as cheap as possible, also in maintenance

That's why the concrete tanks and stone, sand and charcoal

Not have to buy special filter elements that can be expencive and after some years not availeble anymore

Don't know much about ozone, but it will be expencive i guess and need electric?

[Crossy]

Charcoal does NOT remove bacteria. It does however remove many dissolved chemicals.

A UV and / or RO system (or a very fine ceramic) is needed to remove the wildlife.

With gravity feed you're never going to get tank one less than 80% full, tanks 2 & 3 about 60% and the final tank empty.

It may be an idea (if you really need to use the last drop) to plumb the drain points together so you can balance the tanks without filtering if you are short of water.

Thanks for the info

But i not agree with your %s, tank 1 will be filled till the sensor on top unless the sensor in the well shut off regarding the waterlevel in the well.

Your'e right that tank1 have to be 80% full before the other tanks will be filled.

If tank 1 is 90% full, up until the sensor, all tanks will be 90% full, there is no other way

Maybe i lower the connection between tank 1 and 2 to speed up the process

Read my post again.

You will never get tank 1 LESS than 80% full, if the well is dry you will have 80% of tank 1 full of water that you cannot use.

Same with 2 and 3 they will be stuck at 60%.

That's a lot of inaccessible water.

[sappersrest]

The house pump will not be big enough to back wash the filters, you will need a pump with an output of approx 23 meters cubed per hour at t around 10 m head to fluidise the bed.

[sappersrest]

You are looking at a very large scale plant to filter water for just one house you could utilise more tanks for storage,I live in Chiang Mai perhaps we could meet up for a coffee and disscuss your plans.

I can even test your water at no charge. pm me if that suits you .I have over 30 years experience of water filtration with flows up to 800 m/3 per hour, albeit for commercial pools the principal is just the same. but harder for pools as the water is reused.

I am retired and have no commercial interest at all.

[Naam]

Like i point out in the image:

for cleaning tank 1 open valve X1 and wait til the water that come out is clean

for tank 2, open valve X2 and stirring a bit over the sand til the water come out clean

for tank 3, wich is just for bacterial cleaning, replace the charcoal every, what? 2 years?

The well have quite clean water

the water from my well is very clean too but has an extremely low pH (4.8-5.2), that's something you should consider and do some testing.

as far as your eggsburt filtration system is concerned i refuse to comment. even moderator Crossy, who possesses a lot of humour, wouldn't like what i have to say

[worgeordie]

Or you could use Ozone,

regards worgeordie

Well, the whole idea is to make it as cheap as possible, also in maintenance

That's why the concrete tanks and stone, sand and charcoal

Not have to buy special filter elements that can be expencive and after some years not availeble anymore

Don't know much about ozone, but it will be expencive i guess and need electric?

You have nothing to kill bacteria or viruses,Ok if you use the water for washing,general use,

but if you also want to use for drinking,you better boil the water first,Ozone would be the less

maintenance method,as RO filters would cut down water flow and are expensive to maintain.

with Ozone all you would need is Ozone generator,airline,and airstones.

regards Worgeordie

[sappersrest]

Or you could use Ozone,

regards worgeordie

Well, the whole idea is to make it as cheap as possible, also in maintenance

That's why the concrete tanks and stone, sand and charcoal

Not have to buy special filter elements that can be expencive and after some years not availeble anymore

Don't know much about ozone, but it will be expencive i guess and need electric?

You have nothing to kill bacteria or viruses,Ok if you use the water for washing,general use,

but if you also want to use for drinking,you better boil the water first,Ozone would be the less

maintenance method,as RO filters would cut down water flow and are expensive to maintain.

with Ozone all you would need is Ozone generator,airline,and airstones.

regards Worgeordie

Ozone is getting to be very old technology now ,it is probably one of the best oxidisers around , but is very problematical especially with large scale water treatment plants.UV is the way to go now especially with modern medium pressure lamps. The technology in UV lamps is so advanced now full flow UV chambers exist to cope with flows up to 700 cubic meters per hour. I am a bit sceptical though with some of the the under sink treatment packages that claim to have UV lamps that are germicidal more info needs to be put on the packaging and leaflets to show that they are using the correct spectrum.

Phillips lighting produce a really good information pack on their web site.

[Crossy]

If you intend drinking the water too, I would add an RO system in the kitchen. If you get one with a pressurised storage tank the inherent low-flow is not an issue.

Ours has a 10 Litre tank, more than adequate for filling our upstairs drinking dispenser every couple of days and providing water for drinking and cooking.

[willyumiii]

Forget the UV and Ozone.

Save money.

I use the LEO system for drinking water.

It is prefiltered and safe.

Drink beer!

P.S. just a little humor.

This has been a very interesting and informative thread!

Edited May 10, 2015 by willyumiii

[Pib]

^^^Pretty much a ditto....most of my water consumption occurs via consumption of Chang Draught and Pepsi Max. But seriously, I'm lucky in that I live in western Bangkok where the tap water is supposedly drinkable and that's what my family (me included) have been doing for 7 years...but we still run the drinking water through some charcoal filters (one filter on the frig water dispenser and one on a sink drinking water tap) which I change once a year. We are still alive and never been sick from drinking Bangkok water for going on 7 years now.

Edited May 10, 2015 by Pib

[FvH]

Thanks a lot for all your comments

I don't think i need the stone filter after all

and added the backwash pipe

So, i changed the system a bit, see attached file

Still have some questions:

How do i prevent to the sand going into the pipe at tank1 ?

or is it no problem?

And what size of pipe do i use between the tanks, is 1-1/2" (40) enough?

[FvH]

new image:

[sappersrest]

Why do you think you need a charcoal filter?It will give you endless problems .

You will need a distribution pipe at the top of the filter to evenly distribute the water.The same for the charcoal filter

You need to have some sort of collector pipe in the stones either a system of bought swimming pool laterals or make your own ., to stop the sand entering the pipe.The same for the charcoal filter.

You must ensure the pump is correctly sized to backwash the filter.

The non return valves must be able to open under tank head pressure alone

The sand bed must be between 1m and 1.2 m deep.

You must have a final point of use Disinfection system if the water is to be used for showering.

A 100mm backwash drain pipe will be required if back washing at a suitable rate 28 cubic meters per hour per m sq of filter area

On a personal note you are trying to use primitive technology for a 21 century application.

A whole house filtration unit and a couple of storage tanks would be far better and nearly as cheap.

[canuckamuck]

Some good changes there. Take away tank 3 and 4, and the make tank 2 a simple storage tank, and it would look nearly exactly like what I have been using the last 4 years. Your 4 tanks are better than 2 though.

What does the inlet look like that is buried in the stone in Tank one. The one I have I made of 1/2" pipe covered in 2-3mm holes and laid out like a pair of intersecting letter E's. They connect to a 2" pipe at before exiting the tank. I covered them in several inches of stone. and then smaller stones and then aquarium gravel, followed by a plastic mesh with small openings, and then 20 cm of sand. The top sand being very fine.

Gravel in water organizes itself from largest to smallest from the bottom up. So it will tend to stay organized this way, except for some sand will find its way down.

[Naam]

On a personal note you are trying to use primitive technology for a 21 century application.

A whole house filtration unit and a couple of storage tanks would be far better and nearly as cheap.

on a personal note... you took the words right off my mouth. but then, to each his own sophisticated water treatment.