Types of sewage treatment plants?

[MikeABC]

I am needing to install a new sewage treatment plant/digester and am wondering what choice I have.

 

I am aware of 240v with an air pump, I have also come across a non electric type with worms. Perhaps there is a solar version with a 12V pump?

 

How can I check whether a particular plant is Environment Agency approved.

 

Many more questions but thats all for now.

 

Thanks

 

Mike

 

[Stewpot]

I've been researching the same thing. From my notes, here are a few to be going on with:

 

https://www.wte-ltd.co.uk/vortex_sewage_treatment_plant.html
https://clearfox.com/domestic-wastewater-treatment/
www.premiertechaqua.co.uk/products/wastewater/conder-asp-sewage-treatment-plant.aspx
https://webuildit-ltd.co.uk/bio-pure-1/

https://biorock.co.uk/
https://www.graf-water.co.uk/wastewater-treatment.html
www.kingspan.com/gb/en-gb/products/wastewater-management/domestic-sewage-treatment-plants
https://tricel.co.uk/sewage-treatment/sewage-treatment-plants/
https://marshindustries.co.uk/products/ensign-ultra-sewage-treatment-plants/
https://www.clenviro.co.uk/index.php/matrix-sewage-treatment
https://harlequinplastics.co.uk/product-category/wastewater-treatment-systems/
http://clearwatertanksolutions.com/
https://www.wplinternational.com/product/wpl-hipaf-compact-hpc/

 

I'd be interested to hear more about the ones with worms. Have you got a link|?

 

I can't imagine that any of these are not EA approved.

 

Edited August 24, 2021 by Stewpot

[joe90]

I installed a vortex and can’t fault it, it was a bit noisy at first (air pump on top of unit) but now it’s buried in the ground next  to it, it’s much better. From memory one of the cleanest outputs and it can drain to a ditch that’s dry part of the year.

[MikeABC]

Thanks for the replies.

 

Plenty for me to study.

 

The system that uses worms (non electric) is from septictank.co.uk - there may be others, sorry do not know how to put a link up.

 

The blurb says no maintenance required, you may never need to open the lid (or words to that effect). I emailed septictank yesterday to ask about emptying as if you never need to open the lid this suggests it will never get emptied. I await their reply.

 

Mike

[Stewpot]

The worms seem to be intended to unblock a soakaway, rather than as a sewage treatment process. They say their non-electric plant uses bacteria and enzymes, as would any other plant, though it uses 'worm' graphics to illustrate this.

 

The first video that I looked at (www.septictank.co.uk/ecosystem-non-electric-domestic-sewage-treatment-plant) doesn't seem credible, but I'd be interested in what others who use treatment plants would have to say:

 

The chap's five year running costs for a 1-12 person electric treatment plant (most people would use smaller):

Electricity - £3,750 - £5,000  (this equates to over 500W consumption 24/7)
Servicing - £1750+
Repairs - £1500+

 

So, a minimum of £1,400 per year running costs - nearly £27 per week.

 

He then compares that to a non-electric plant, which he tells us would cost £5 per year (a £25 bag of bacteria every 5 years).

 

He is, of course trying to sell his own brand plant. I get the feeling that in another life, he would have been selling pyramid schemes, but that's not to say the treatment plants themselves are no good. But the prices take a bit of, err..., digesting: 1-6P  £11k + VAT + delivery (reduced for Covid to £5K + VAT etc.).

 

[ToughButterCup]

On 24/08/2021 at 20:33, MikeABC said:

...

How can I check whether a particular plant is Environment Agency approved

...

 

Simples! Ask the manufacturer. I have no idea whether ours is - maybe I should.

 

[dpmiller]

1 hour ago, Stewpot said:

 

The chap's five year running costs for a 1-12 person electric treatment plant (most people would use smaller):

Electricity - £3,750 - £5,000  (this equates to over 500W consumption 24/7)
Servicing - £1750+
Repairs - £1500+

 

So, a minimum of £1,400 per year running costs - nearly £27 per week.

 

He's having a laugh. He looks like he's comparing to one of them rotary jobbies with the motor in the sh*te, but even at that...

Air blower units only use about 50W, and the blower often doesn't run 24/7

[MikeABC]

16 hours ago, ToughButterCup said:

 

Simples! Ask the manufacturer. I have no idea whether ours is - maybe I should.

 

Just read the following on WTE LTD web site

 

Sewage treatment plants must be to EN 12566 part 3

 

However.....

 

EN12566 part 3 only tests the percentage reduction of the influent pollutants in the sewage and gives no guarantee the final effluent quality will satisfy the Environment Agencies final consent standards.

 

Mike

[PeterW]

They are also the site that sells an IBC converted into a treatment plant that is somewhat “dubious” in its capabilities … 

 

If I’ve looked carefully, that is a pair of rotomoulded tanks and some baffles with standard pipe connectors - probably £3-400 of parts maximum in the £5k model …

[Stewpot]

3 hours ago, MikeABC said:

EN12566 part 3 only tests the percentage reduction of the influent pollutants in the sewage and gives no guarantee the final effluent quality will satisfy the Environment Agencies final consent standards.

 

That may be just a catch-all clause to cover themselves if the way you install it doesn't meet requirements, or if there are special circumstances pertaining to your site. I can't see how any manufacturer would hope to sell any units if they didn't make them to meet the requirements. You will need to get Building Regs. approval on your intended installation, and, depending on how you intend to deal with the outflow, you may need to consult with the EA, too.

 

Just to add, my Architectural person recommends Marsh Ensign or Klargester Biodisc  - from my research, the cheapest or the most expensive.

Edited August 27, 2021 by Stewpot
clarity

[joe90]

From what other,s have said avoid plant with moving parts in the smelly stuff.

[saveasteading]

On 27/08/2021 at 11:51, Stewpot said:

Marsh Ensign

Marsh are my favoured suppliers. Small business, really good advice on the phone. Also they deliver themselves (regardless of the merchant you go through) and are as keen as you are that there is access and offloading organised.

 

On 27/08/2021 at 12:18, joe90 said:

avoid plant with moving parts in the smelly stuff.

just an air pipe, like in a fish tank.

[saveasteading]

Another thing to look at is depth. Some of these tanks are high, others are long. This then requires an excavation to a greater or lesser depth.

Safety-wise it is always best to be shallow, and someone is going down that hole to spread the concrete base, whether shore or not.

It depends on the ground too as to easy or difficult digging.

 

A deeper one may be fine if there is limited space, or if your drains are already deep by that position (but if so, why?).

[ProDave]

1 hour ago, saveasteading said:

Another thing to look at is depth. Some of these tanks are high, others are long. This then requires an excavation to a greater or lesser depth.

Safety-wise it is always best to be shallow, and someone is going down that hole to spread the concrete base, whether shore or not.

It depends on the ground too as to easy or difficult digging.

 

A deeper one may be fine if there is limited space, or if your drains are already deep by that position (but if so, why?).

The "conical" shaped ones like the conder and the Bio Pure don't need much of a flat bottom to the hole, and don't need you to pour a flat base.  We lowered our Conder in, then started pouring the concrete, filling the tank with water as we went.  Nobody had to go down the hole.

[saveasteading]

1 hour ago, ProDave said:

don't need you to pour a flat base

interesting. worth another look perhaps. 

[ProDave]

31 minutes ago, saveasteading said:

interesting. worth another look perhaps. 

Yes, here it is being lowered into the hole:

 

It stands upright on those 3 legs just on the ground, then you start pouring the concrete in.

[saveasteading]

How many fills of that mixer? I don't suppose it has to be in one pour though as it is dead weight, not structural.

What size of digger is that?

[ProDave]

5 minutes ago, saveasteading said:

How many fills of that mixer? I don't suppose it has to be in one pour though as it is dead weight, not structural.

What size of digger is that?

That was my very old 3 ton Komatsu digger, i would guess 1980's.  It was a chance ebay purchase (cheeky low bid to test the market and I won it)  It came from Grantown, not far from you I guess.  It was old and very worn with a lot of play in all the joints but it worked if not always very gracefully.  After using it for 3 years and finished all the heavy work I sold it for exactly what I paid for it, still working.

 

Once we had put the tank in me and SWMBO spent the rest of that day and most of the next day mixing barrowing and pouring.  We were well worn out by the finish.

 

That old mixer still works, it's so tatty looking nobody would nick it.  I saw it in someones garden where I was working once and asked if he wanted to sell it.  No he said but you can borrow it.  So I borrowed it and when I had finished that job I contacted him to arrange to take it back.  "Oh no I don't want it back"