Wastewater lagoons
Three to four feet of crust across the lagoon, and a pump-out that took two full days because of it.
less pumping time
01The plant
A 67,500 cubic yard dairy waste lagoon, drawn on for irrigation.
02Before
A manure mat and crust three to four feet thick had set up across the whole surface — fibrous material arriving faster than it broke down, floating, matting together and consolidating. It cost the farm twice over: it occupied storage volume that should have been holding liquid, and it made drawing irrigation water off the lagoon slow. A single pump-out was taking eighty hours, on a schedule the crop set rather than the farm.
03Treatment
Dosed weekly across a forty-five day window. Nothing else about the operation changed — no dredging, no added agitation, no equipment and no extra labour, and the lagoon kept taking waste as it always had.
Every result in this library was measured at an operating plant treating with one of the formulations SediLogic supplies, over the window stated above. It is a field result published as reported, not a controlled trial we ran.
04Method
Open water across the surface, crust thickness and the hours needed to pump irrigation water off the lagoon, read at day 30 and again at day 45. The pumping hours are the useful number here, because they are the one the operation actually feels.
05Outcome
Forty-two hours back per irrigation event, and the storage volume the crust had been occupying returned to the lagoon.
At the start
Three to four feet of manure mat and crust across the surface, and eighty hours to pump a cycle.
At the close
Crust cleared, about 95 per cent open water, and thirty-eight hours to pump — a 52.5 per cent reduction. Scum, bottom sludge and suspended solids all reported substantially down.
06Limits
Pumping time is a proxy. It is a good one, because it is what the farm pays for, but it is not a measurement of solids and nothing here was sampled or analysed. Open water was assessed by eye. No volatile fraction is recorded at either end, nothing was left untreated, and forty-five days of a dairy lagoon is forty-five days of weather that nobody logged. That the routine did not otherwise change is the publisher's account of it.
Only the volatile organic fraction of a sludge responds to any of this. Grit, sand, silt, mineral precipitates and plastics remain at any dose, here and everywhere else.
—What we would supply
Spike and Puck are sinking solids for bottom sludge. Maintain is a soluble pouch for organic load in the water column, with Polar for cold-water conditions. The planner calculates quantities only for products with a written dose method; Puck and Polar need a separate review.
Use the written dose method for your product and lagoon. A quantity reported in a case study was chosen for that site and should not be used as your application rate.
—Read next
Wastewater lagoons
Municipal24 weeks
of accumulated solids digested
Just over five feet of accumulated solids in the primary aerated lagoon, assessed at 2,365 dry tons. The plant wanted a route that did not involve dredging.
Wastewater lagoons
MunicipalFive months, May to October
reduction in solids volume overall
Accumulated solids across two lagoon cells, against a specification calling for a 50 per cent reduction. The treatment window was bounded by water temperature, which has to stay above roughly 55°F for the organisms to work at all.
Wastewater lagoons
Municipal3 months
of organic solids digested
Decades of loading had taken the lagoon to a measured 20.5 per cent solids, with a dredging quotation in hand and no budget line to meet it.
Your lagoon next
This result came from a different plant. Your sludge composition and operating conditions need their own assessment. Send us your lagoon details for a dosing review; do not use the quantity on this page as your application rate.
