Wastewater lagoons
A lagoon system less than two years old, taking 3,400 lb of BOD a day, already accumulating solids faster than the design allowed for.
reduction in sludge volume over twelve months
01The plant
Two facultative cells at an industrial works — a 6 million gallon primary and a 4 million gallon secondary — carrying about 3,400 lb/day of biochemical oxygen demand.
02Before
The lagoons were under two years old and already accumulating fast enough to cut working capacity, with the accumulation at 7.75 per cent of the primary cell.
03Treatment
An opening treatment of the primary cell followed by a monthly maintenance dose, run for twelve months.
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.
04Sizing
The opening charge was set against the volume of the primary cell, with monthly maintenance at a fraction of it thereafter — an opening charge against what is standing there, maintenance against what keeps arriving. The concentrations belong to this lagoon's volume and loading and are not carried here.
05Method
Sampled with a sludge judge every 60 to 90 days across the twelve months, with each sample sent to an outside laboratory.
06Outcome
Working volume was reported as restored. The shape of the curve is the useful part: most of the reduction arrived early, which is what a treatable organic fraction being consumed looks like.
At the start
Accumulation at 7.75 per cent of the primary cell, working capacity falling.
At the close
84 per cent less accumulation after twelve months, with 52 per cent of that inside the first ninety days.
07Limits
Nothing was left untreated. The secondary cell was not treated but was not reported either, so it cannot serve as a comparison. The volatile fraction is not given, so there is no way to tell how close the 84 per cent came to the ceiling on what could respond at all.
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
This is the duty SediLogic supplies and sizes. Which article depends on where the material sits: Sedivore Spike is the denser solid and carries down through depth to an established blanket, Sedivore Puck is a smaller unit that spreads a calculated dose across the bed, and SediLogic Maintain is a soluble pouch for load carried in the water column — with Sedivore Polar for that same duty where the water runs cold enough to stall a standard blend.
A quantity for your own lagoon comes from the dosing planner, sized against your dimensions and loading from the manufacturer's written dose method. It does not come from the figure on this page, which was set for a lagoon that is not yours.
—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
A different plant, a different loading and a different sludge. What decides your result is how much of your own accumulation is organic and treatable, and whether the dose is sized against the lagoon in front of us rather than read off this page. Tell us the dimensions and we will size it.
