System design - mains and well combination.

[Fallingditch]

On 10/01/2018 at 13:17, JSHarris said:

Thanks, I'm trying to work out the simplest system to reduce the manganese level in your water, that won't cost and arm and a leg and which can be easily DIY installed.  ...

 

... given your marginally high manganese level, with no other notable contaminants to take up oxygenation capacity, I would opt for their smallest Aquamandix unit, with the air draw kit (which is £27 extra and will be needed as manganese oxidises more slowly than iron).  This is the unit and it comes complete with media, timer, etc: http://gapswater.co.uk/acatalog/Aquamandix---sand-mix-Simplex-system-with-Autotrol-Logix-263-740-digital-TIME-controller-2968.html#SID=241

 

You have two choices as to where to fit this unit.  If your pump can deliver at least 1100 litres per hour (just over 18 litres/minute) at around 2 bar or more, for at least 8 minutes, then fit it immediately after the pump, and before the pressure vessel ...

 

 

I have recently received my water analysis results. (Should have done this some time ago!!). Results posted elsewhere on the site.

 

pH equals 7.1

Hardness equals 395 mg per litre (very hard)

Iron is less than 0.1 mg per litre

Manganese is 0.61 mg per litre

 

My 4/5 bed new build is on low lying land. All water is drawn from a borehole. Because the aquifer is only about 2 m below ground level, we use a simple self priming centrifugal pump ESPA Delta 1755m with a raising capacity of 9 m.

 

Water is stored in a 500L pressure vessel next to the pump in the garden shed.

 

It then flows through a 5 micron water filter, and then a blackthorn ultraviolet sterilising unit before travelling underground through 28mm pipe a short distance to the house

 

(I plan to install a water softener downstream of the sterilising unit in the house).

 

Part 42 of the House at Mill Orchard describes how Jeremy injects ozone into his supply using his home-brewed generator, feeds the water into an accumulator, and then passes it through an Aquamandix and sand filter to wash out the accumulated oxides, before passing it through filter and softener

 

An update to Part 42 suggests that Jeremy could have done it in a simpler manner by using a smaller filter with aeration, and Turbidex filtration media (rather than Aquamandix).

 

However in responding to Albert on this page, Jeremy suggests using the same Aquamandix unit as is installed at Mill House, but locating it upstream of the accumulator, and with no ozone generator.

 

I think I need to remove the manganese from my supply because of its undesirable staining effect on sanitary equipment and because of the effect it has on water taste.  So I need to install a Turbidex or Aquamandix, and I need to size its filter housing.

 

I wonder if @JSHarriscould suggest which solution I should go for?

 

[Jeremy Harris]

I'd suggest using the Aquamandix unit with the air injection option.  I went for ozone injection because we have a very high iron concentration in our water, well over the acceptable limit for drinking water, and also because we have some hydrogen sulphide, and the combination of the two still resulted in the water having a funny taste and smell, even after the aquamandix filter.  Injecting ozone into the raw water, and adding a contact tank, completely fixed our water taste and smell problem, and had the advantage of being a pretty good disinfection system.

 

However, finding a supplier of an ozone injection system here in the UK proved challenging and expensive, so I opted to make one.  This involved machining up the injection venturi (which itself involved a bit of trial and error) and building a home made ozone generator and air drier.  I'd not recommend that anyone goes down the ozone injection route unless they really need to, or they have an interest in making a system themselves.  The ozone system does work very well for our water, but we have 480µg/litre of iron, versus your 100µg/litre, with the acceptable maximum for drinking water being 200µg/litre.  Given that you don't have an iron problem and you don't have a hydrogen sulphide problem, then I think ozone injection would be over-kill for your needs and an added complication. 

 

Best keep it simple, with an off-the-shelf solution that you can easily get spares for, I think.