Choice of treatment plants

[Stones]

It's fast approaching the point where I have to decide which treatment plant i am going to install.  I've narrowed it down to either of these two, having discounted the unit normally installed locally (Klargester Biotec).

 

The two contenders which I can easily source or have delivered up here are:

 

Biopure - http://www.bio-pure.com/?gclid=CO2dvf2Qoc4CFUmeGwodXOoKxA  also available on Ebay at a lower price

 

Conder ASP6 - https://www.septictank-supplies.co.uk/index.php?route=product/product&path=66&product_id=597

 

Both seem to be in effect very similar units, operating on the same principle / in the same way.  Just looking for any feedback / comments.

[Calvinmiddle]

I have the bio- pure, no thing bad to say about it, although not yet been used in anger!

 

But they were helpful to deal with and were able to suggest alternatives when I didn't want the pump in the ground on top of unit.  I have it remotely sited and they helped sort out what I needed to do this.

[ToughButterCup]

From memory;

• The least number of moving parts
• An alarm system (power failure)  that warns you from inside the house
• if you are going to have an aerator, install it in the house  and bury the airline 
• install a grease trap in the line to the digester
• think about washing up liquid and washing powder

I'll look up the thread later today... might have been on ebuild

 

[Stones]

11 hours ago, Calvinmiddle said:

I have the bio- pure, no thing bad to say about it, although not yet been used in anger!

 

But they were helpful to deal with and were able to suggest alternatives when I didn't want the pump in the ground on top of unit.  I have it remotely sited and they helped sort out what I needed to do this.

 

Good to know, thanks.

 

10 hours ago, recoveringacademic said:

From memory;

• The least number of moving parts
• An alarm system (power failure)  that warns you from inside the house
• if you are going to have an aerator, install it in the house  and bury the airline 
• install a grease trap in the line to the digester
• think about washing up liquid and washing powder

I'll look up the thread later today... might have been on ebuild

 

 

Having previously paid a lot of money for something which really didn't work as advertised, I'm content that the two choices I've narrowed down to meet the simplicity / minimum moving parts test.  An alarm unit is in hand, as are grease traps and as we have lived with off mains drainage for many years, the consistent and sensible use of the same detergent and cleaning products.  The one thing on that list I wouldn't do is house an aeration pump inside the house.  We had such a pump in a garage two houses ago and it was far too noisy for me to consider having one inside.  For me, it's either in the dedicated space within the unit or a housing nearby.  

[Stones]

On 8/2/2016 at 07:47, Calvinmiddle said:

But they were helpful to deal with and were able to suggest alternatives when I didn't want the pump in the ground on top of unit.  I have it remotely sited and they helped sort out what I needed to do this.

 

Out of interest, why did you opt to remotely house the pump?

[Calvinmiddle]

Unit is in the corner of the lawn, we are tight for space so didn't want to have an unslighty green lid on the grass, so we have used a man hole cover that holds grass on the top so it's not really noticeable.

 

Pump sits a few metres away on a raised garden beds from where we had to dig down into the slight slope.

 

Some pics here

Edited August 4, 2016 by Calvinmiddle

[ProDave]

I have the Conder, the second link in your original post.  you might care to get a quote from TP if they have a branch on the island, they were the cheapest I could find so they supplied mine for less than I could find with any of the in line suppliers, and delivered and ofloaded by their own truck with a haib.

 

I chose the conder over the biopure, because of the ground anchoring arrangements. The ground anchor kit for the boipure appeared to require someone to go down into the hole to fix the anchor kit into the ground. With the Conder you just have to fill the bottom of the hole with concrete high enough to encompass the ring about 1/4 the way up from the bottom of the cone shaped bit. The Conder also sits on 3 legs in it's hole whereas the boipure requires the digger (or whatever you lowered it into the hole with) to hold it upright while you back fill the hole.

 

On the downside, I believe the Conder uses more power for it's air blower. 

 

[Stones]

Your description of the differences between the two matches what I've read,  although there is reference in the Biopure installation guide, that in high water areas you can back fill around the base of the Biopure with concrete to anchor it.  

 

As my builders will be installing rather than DIY, I don't have exactly the same requirements in terms of installation - we have a loadall on site so keeping it in position while they backfill wouldn't really be an issue for us.

 

Having made a few more enquiries, it's looking like it will be the Biopure, as they will deliver to me up here for an extra £120.  No TP up here (nearest Thurso), and despite me referencing your order they want £1750 for the Conder and I still have to arrange the last leg of transportation.  Tried the local BM's but all they want to sell (for a reasonable price) are Klargesters.  Most of the other online sellers will happily deliver to Aberdeen for free, but the onward transport costs (priced per pallet space) push the final cost up to more than the Biopure.  

 

The lower running costs of the Biopure, circa £35 p.a. will start adding up over the air blowers life time.

 

 

[ProDave]

Can you not get one to Cumbernauld in time to be delivered by the same transport company as your windows?

 

It was only the ease of DIY installation that swayed me to the Conder, I have every faith the Biopure would perform as well and be slightly cheaper to run.

 

At the moment the £120 delivery looks your best option.
 

[Stones]

9 hours ago, ProDave said:

Can you not get one to Cumbernauld in time to be delivered by the same transport company as your windows?

 

Unfortunately, doesn't really help, as I'm paying per pallet space for that particular haulier.  Just one of those purchases where I'll have to take the extra haulage hit.

[pauldoc]

Kinda jumping in here but on the same subject.

has anyone got an opinion on the vortex plant? 

Looking at it it allows you to reduce its capacity if it's underused 

 

[ProDave]

When I was looking to decide which one to use, I also looked at the Vortex. The Vortex, the Biopure and the Conder seemed to be the best 3 available in terms of effluent quality so it came down partly to price and partly to installation method in (in my case) ground with a high water table.

 

The Vortex, being a cylindrical unit, appeared to require the whole thing to be encased in concrete if installed in a high water table area so I discounted it for that reason.

 

If you are happy with the installation method for your ground conditions I see no reason not to use it.
 

[pauldoc]

Thanks Dave good to know , I haven't got a high water table so don't think that will be an issue. My main concern from research is that an under used one can be as much a problem as one not big enough. The vortex says it is unique in that it is the only one that can be adjusted if under used. I think we will poss have that problem (if indeed that is an issue?) as we will have 5 beds so will have to specify to that but as with most families won't be filling them all!

[Stones]

Just had a closer look at the Vortex - certainly looks to be a strong contender. Just waiting to hear back about delivery...

[ProDave]

If you are looking at alternatives still, there is also the diamond. http://www.drainstore.com/wpl-dms2-sewage-treatment-plant-6-population.html

 

Yet another Biopure conical type plant.  I discounted that one because for my ground conditions it would have to be fully encased in concrete to within 150mm of the lid.
 

[Stones]

After a bit more digging and establishing the additional carriage costs, I've discounted the Conder, which leaves the Biopure, and the late contender, the Vortex.

 

Delivered price for the Biopure £1820 

Delivered price for the Vortex £1922

 

Both use lower power air blowers, the main difference being the Vortex blower doesn't run 24/& so running costs are slightly cheaper.

 

The main question now is which design is better - conical or cylindrical?  There certainly appears to be a lot more conical designs on the market compared to only two (that I can find) cylindrical designs.  The relative abundance of conical designs suggests that this is a proven and tested design, whereas it is more of an unknown with the cylindrical design.

 

Any thoughts on the merits of conical vs cylindrical, pros and cons?

[Stones]

So, I've been looking a bit more into the Activate Sludge process to try and determine which is the optimum shape - conical or cylindrical.

 

The short answer is I can't find definitive information and that various shapes of 'tank' seem to work.  The main difference between the two units seem to be the size of bubbles produced by the air diffuser.  The Biopure appears to produce larger bubbles, as it has to both aerate and break up solids that are deposited directly into the digestion chamber.  The Vortex has an initial breaking up stage before using a diffuser that produces finer bubbles in the main chamber.  Whether there is a greater risk of a finer diffuser getting blocked / scaling up is something to think about.

 

The Vortex also appears to only aerate part of the time as compared to the Biopure which runs 24/7.  The Vortex also claims to be adjustable to deal with household under occupancy.  I'm not sure how bug an issue this is.  presumably a variable resistor fitted to the air blower would be an option to reduce the amount of air / oxygenation going into any treatment plant.

 

I'm still to confirm service requirements for the Vortex, but a chat with Biopure, it all seems straightforward.  Service the air blower (filter and diaphrams), sample treated liquor, desludge every 3 or so years, lift air line to check and clean diffuser.  I'm guessing the Vortex will be similar.

 

One advantage the Biopure does have is that the air blower can be housed in the top part of the unit whereas the Vortex seems to be a little box that sits on top of the unit.

[mafaldina]

I'm following you closely on this one. I had narrowed my choice down to the same two. My inclination is to the Biopure (feels better designed and as far as I can make out longer emptying intervals) but the Vortex has other merits: adjustable (I am connecting three properties, at least one of which, half of the population, is a seasonal let); possibly easier to put in, straight sided hole just backfill with sand rather than gravel; has built in sampling point and outlet higher than inlet: better positioning in soil – less deep, I have no running water near me). Don't like the above soil bit for blower on Vortex though.

 

Might end up tossing a coin

[Stones]

I'll hopefully confirm the servicing requirements of the Vortex tomorrow.  

 

Household under occupancy is an interesting one as building regs require us to install on a population basis which often bears no relation to the actual occupancy.  Not sure what the answer to that is, the dual approach of the Vortex (intermittent running of air blower and ability to adjust air blower), replicating that approach by timing air blower operation and fitting a variable resistor to control blower output or simply using a smaller air blower.

[ProDave]

the occupancy thing is interesting. Not so bad in our new house which will have 3 living in it, BR demand a unit sized for 5 people, which rounds up to a 6 person plant in out case.  but our existing 5 bedroom house (still with just 3 of us most of the time) has a system sized for 8 people.
 

[Roundtuit]

I've just ordered a Biopure 2.  After talking through the occupancy question with them (2 teenage kids that are not going to be around full-time in a few years..) it sounds as though a timer fitted to the air pump is good practice, so performance can be tweaked.  I'm siting the air pump external to the tank, just 'cos I don't fancy servicing anything that lives in the bog of eternal stench.

[mafaldina]

Useful info Roundtuit thanks. Stones are those prices ex VAT?

 

[SteamyTea]

Mafaldina

There must be a wealth of knowledge down here about sewage treatment plants as there are loads fitted.  Such a shame that there is no way of easily getting the info.

 

 

Ian

I am sure you meant to say the air pump should be in a building, not in the house.  If in the house, it will suck out the warm air (which may help digestion) and play havoc with the MVHR,

 

I don't know much about these units (just used to see Klargesters units a lot when I lived in Aylesbury), but I suspect that there is a lot of nonsense said in the brochures.

They basically work by agitating and aerating the sewage.  So bubble size should not make any difference (within reason) as it is the total energy needed, not the instantaneous energy.  So a simple timer is probably all you need to 'clean' each 'batch', think of it as a multiple batch process rather than a continuous process.  So air volume x time is the important metric rather than bubble size, which is a proxy for surface area (small bubble, greater area, but less energy).

Keeps as many things that have to be changed out of the ground (so all pumps, gears, switchgear in 'the shed).

 

As for shape, spherical or conical, this may make a difference for smaller volumes.  Just a case of knowing the sizes and volumes.  A sphere will have a greater top surface area than a cone for any given height, volume or in this case, the mass of waste in it.

 

Edited August 15, 2016 by SteamyTea

[ProDave]

If you turn off the air blower, would there not be a danger of sludge settling on the air vents and blocking them?
 

[pauldoc]

On ‎11‎/‎08‎/‎2016 at 09:24, Stones said:

After a bit more digging and establishing the additional carriage costs, I've discounted the Conder, which leaves the Biopure, and the late contender, the Vortex.

 

Delivered price for the Biopure £1820 

Delivered price for the Vortex £1922

 

Both use lower power air blowers, the main difference being the Vortex blower doesn't run 24/& so running costs are slightly cheaper.

 

The main question now is which design is better - conical or cylindrical?  There certainly appears to be a lot more conical designs on the market compared to only two (that I can find) cylindrical designs.  The relative abundance of conical designs suggests that this is a proven and tested design, whereas it is more of an unknown with the cylindrical design.

 

Any thoughts on the merits of conical vs cylindrical, pros and cons?

Could you tell me what occupancy 'size' these are pls?