Wastewater lagoons
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.
reduction in solids volume overall
01The plant
A three-cell municipal lagoon works. Cells 1 and 2 were treated; cell 3 has no aeration and was left out of the programme and out of the result.
02Before
Both treated cells were carrying heavy accumulation — averaging 52.3 inches in cell 1 and 43.6 in cell 2 — against a project specification that called for the solids volume to come down by half.
03Treatment
Weekly through the warm season, from 15 May to 11 October, mixed as a slurry in a five-gallon bucket and applied from a boat whose trolling motor was used to work it into the water. New aeration equipment went into both treated cells over the same period.
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
Weekly applications across the warm-water window rather than a single charge. The window itself is the constraint: below roughly 55°F the organisms effectively stop, which is why the programme starts in May and ends in October.
05Method
Sludge-gun surveys across each cell before and after — the same method at both ends, which is what makes the two numbers comparable with each other.
06Comparison
Cell 3 went untreated. It was excluded from the result rather than reported as a control, so it is not a control — but it is the nearest thing in this library to one, and the two treated cells differing by nearly forty points is the more useful comparison anyway.
07Outcome
48 per cent across the two treated cells, against a specification of 50. A reported drop in solids carried in the water column, and an accumulation layer that appeared less dense than it had been.
At the start
Cell 1 averaging 52.3 inches, cell 2 averaging 43.6 inches.
At the close
Cell 1 down to 11.7 inches, cell 2 down to 24.0 inches.
08Limits
Aeration equipment was installed in both cells during the same window, so the result cannot be attributed to the product alone — this is the clearest confounder in the library and it is why the record carries the mark. Cell 3's readings were not published, so the untreated cell cannot be used as a baseline.
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
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.
Wastewater lagoons
Industrial12 months
reduction in accumulated solids
Accumulated solids had cut hydraulic retention time to 13 days, capping what the facility could put through the plant and putting effluent quality within sight of a limit.
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.
