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Precise Dairy Effluent
NZ’S LEADING DAIRY EFFLUENT STORAGE BLADDERS It’s unique design makes removing solids from the bladder easy
Vortex Bladders not only offer the many advantages of a standard storage bladder/ flexible tank, but also offer an effective and hassle-free solution to removing solids from the bladder.
This is done by delivering the solids to the centre and bottom of the bladder where the central drain hole is located, and with a few other innovations it makes the Vortex Bladder a leader in its field. Let’s face it the removal of solids from all types of storage options is a real challenge, but the Vortex Bladder was always designed to help address this issue.
When you get a Vortex Bladder from us, you also get expert and Regional Council recognised accredited advice on sizing your storage and how to get your Vortex Bladder to work effectively with the infrastructure you have already or are going to need, as we are experts
in “Anything and Everything Dairy Effluent” and are “Farm Dairy Effluent
System Design Accredited”, we are not just a supplier of bladders/flexible tanks.
Allan Crouch, Angus Clarke and Brian Nicholson are veterans in the dairy effluent world. With over 50 years of experience in the industry between them, and the designing of hundreds of effluent systems in New Zealand – and further abroad – under their belts.
‘For anything and everything dairy effluent’ is their slogan, and it’s not an exaggeration. At Precise DE Allan, Angus and Brian supply advice; design effluent systems suited to each specific farm they work on; supply products, from storage solutions to irrigation equipment; regardless of where in the country their customers are, through a network of
trusted and experienced dealers close to you.
Contact us at www.precisede.co.nz
Farm Dairy Effluent System Design Accredited
PRECISE DE
For ANYTHING and EVERYTHING Dairy Effluent www.precisede.co.nz
GREEN WATER YARD WASHING A NO-BRAINER!
By Logan Bowler
WHEN CALCULATING HOW MUCH EFFLUENT STORAGE
is required on individual farms, there are several options for reducing storage requirements.
One that has many benefits, other than just reducing storage, is using recycled effluent (green water) for washing the yard.
The volume of water used in the dairy shed and yard has a large impact on storage requirements.
In general, for a normal herringbone shed using 70 litres of water/cow/day, 10% of the water is used for plant washing, 25% is used for hosing out the bail area and the rest (65%) is used to hose the yard. So, by installing a green water yard washing system, daily water use can be slashed by up to 65%.
The many benefits add up to a compelling reason to seriously think about implementing this onfarm.
These include electricity saved from pumping a lot less water from source (surface water or bore), halved pumping time for effluent irrigation and labour-free washing of the dairy shed yard.
On an example Waikato farm, it resulted in a whopping 74 fewer effluent runs (200-metre runs) per year with the effluent irrigator.
That’s a saving of 74 times each season someone needs to turn the irrigator around and set up a new run. On top of all this, there is a significant drop in required storage volumes and the costs associated with that. If you are winter milking the benefits of storage reduction are even greater.
Depending on soil risk in the effluent block, an average Waikato dairy farm implementing green water yard washing will reduce storage by about 50%. Their modelled pond dimensions go from 50m x 46m x 4m to 36m x 36m x 4m, and their annual effluent production (including rainwater landing on the pond) goes from nearly 11 million litres to about 5.5 million litres!
For those who already have storage but it’s too small, green water yard washing may make the old pond “fit “the farm again. For those with sufficient storage, green water use effectively doubles storage giving easier and more flexible management of effluent. Effluent irrigation on any pasture also becomes more efficient. With increased nutrient concentration of effluent, each litre becomes more valuable. There has been no reduction in the volume of nutrients being captured - just the water that the nutrient is suspended in has been reduced.
If you are not convinced that this is a good idea all season because you think it might smell or attract flies (those that have made the change don’t find these an issue), just use green water on the shoulders of the season.
This is the time when soils are still often wet and effluent irrigation days few and far between. If you commit to using green water for the first three months of the season and the last six weeks of the season you will still get the full benefit of storage reduction. There is no real reason to not do this.
There are rules that must be met on how you use green water for washing the yard. Talk to your accredited effluent designer, your milk company or go to DairyNZ’s website for the actual rules.
The main rules are: • The green water must be free from sediments and solids • It can only be applied at low pressure to eliminate any aerosols • It can only be applied no higher than 300mm from the yard surface • It must not be used within 5m of any milk harvesting equipment • It cannot be used when cows are on the yard • You need to have the ability to wash the yard with clean water (this may just be from a hand-held hose)
Once a farm has storage there is a source of settled effluent ready to be pumped back to the yard for cleaning.
For those with flood wash, it’s simply changing the filling of the tanks from clean water to green water (talk to your milk company regarding the proximity of flood wash tanks to the shed).
Farms with under-gate washing systems need to organise a separate effluent line to the gate that enables getting the green water into the washing system with no chance of contamination of the shed’s fresh water supply.
If you are looking at putting storage onfarm the cost of implementing green water may well be met by the money saved from smaller storage. You’d be mad to not consider this!
• Logan Bowler is an independent effluent management expert.
He can be contacted directly on 021 225 9415 or email logan. bowler@yahoo.co.nz
Significant savings are there for the taking by installing a green water flood system for the yard.
Under-gate wash systems need a separate line for getting the green wash to the gate.
The Ecobags tank for storing shed effluent on Abe and Anita de Wolde’s Southland dairy unit can hold 8000 cubic metres of material.
EFFLUENT - IT’S IN THE BAG
SOUTHLAND DAIRY FARMER
Abe de Wolde installed his first Ecobag Effluent Storage System in New Zealand for the storage of wintering barn slurry last year.
“They’re well used and well regarded in Europe but this was a first for New Zealand,” he sAYS.
And he’s so impressed he’s installing a second one in mid-January at a new wintering barn he’s building.
The 45-metre by 45m bladder, supplied in NZ by Technipharm, is 4.8m deep, and can hold 8000 cubic metres of effluent. It sits in the ground and when full is 75cm above the surface of the land.
As the effluent is not exposed to the environment there is no crusting, no odour and it’s completely safe.
“You can walk over it, there are no worries about anyone falling in.
“The big benefit is there is no volatilisation of nitrogen as methane, as there is no contact with air so the slurry we’re spreading on to the farm from the Ecobag is higher in nutrients.
“Our slurry is giving off very little methane and nitrous oxide so it’s good for us and good for nature.”
Abe’s Woldwide Dairy Group milks 4200 cows on five dairy farms near Winton.
The 2300 hectares produces about 2.5 million kg of milksolids a year from the mainly Friesian cows which have a mix of NZ and Dutch genetics.
Abe and his wife Anita moved to NZ from Holland in 1992 after milking 40 cows there on 26ha. They were one of the first farming families to convert sheep farms into dairy in Western Southland.
Right from the start they saw the possibilities of bringing European technology and farming systems to Southland.
“It’s our goal to combine the best farming systems from around the world to produce food more efficiently,” Abe said.
Very soon their first dairy farm had a 625 free-stall wintering barn built on it.
Now cows on four of their five farms go in the wintering barns at night in April and May, extending the round so milking can continue through until the end of the season. Then they are in them fulltime in June and July with the cows milked until they are sixty days away from their expected calving.
Some of the barns are also used for calving in August and September.
Automatically scrapers travel the length of the barns eight to 10 times a day with no water added but the slurry still contains enough moisture for it to be spread when soil conditions are right.
And Technipharm’s Ecobag helps.
“As the effluent is completely enclosed it doesn’t dry out but also rain can’t get in so we don’t have more slurry than we need to spread on our paddocks.”
A 18kw stirrer keeps the contents from separating.
“It goes from about two until three in the morning, well I hope it’s going – no one is awake to hear it.”
He said regional council Environment Southland was supportive.
“The Ecobag came with very good instructions and specifications so they could see that it met all of the consent requirements.”
Effluent is spread mainly on silage paddocks using either a slurry tanker on an umbilical when soil moisture conditions allow which hasn’t been easy these past few months in Southland.
“We’ve had the most horrendous Spring, the worst we have known. It’s been very
