Wastewater lagoons
A lagoon loaded well past what it was built for, carrying a foam layer across most of the surface and blocking the irrigation draw.
reduction in total suspended solids
01The plant
The waste lagoon of a South American agricultural company running eight thousand dairy cows.
02Before
The lagoon was taking considerably more than it was built for. Solids arrived faster than they broke down, a foam layer closed over most of the surface, and the irrigation draw had to come through it.
03Treatment
A solid dosing form that dissolves quickly, applied to the lagoon over four months from October through January, rather than a metered liquid.
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.
At the start
Suspended solids 18,650 mg/L, BOD₅ 5,195 mg/L, chemical oxygen demand 18,211 mg/L, foam across most of the water surface.
At the close
Suspended solids 3,220 mg/L and BOD₅ 2,752 mg/L. Chemical oxygen demand had risen, to 19,303 mg/L, and around seventy per cent of the surface was reported clear.
04Limits
The chemical oxygen demand figure is the one to sit with: it went up while suspended solids came down by eighty-three per cent, over the same four months in the same lagoon. A rising COD alongside falling suspended solids is what you would see if solids were being broken into dissolved organic material faster than that material was being oxidised — treatment part-finished rather than treatment failing — but that is a reading, and the record establishes none of it. The window ran October to January, which south of the equator is the warm half of the year, and warmth alone moves a lagoon. No volatile fraction at the start, no dosing detail, and nothing left untreated.
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
Municipal30 days
effluent suspended solids, from a starting figure that was never recorded
A forty-year-old lagoon carrying heavy accumulated solids and an effluent suspended-solids figure the resort could not hold.
Wastewater lagoons
Agricultural6 weeks
reduction in total suspended solids
Suspended solids and phosphorus in a manure lagoon at concentrations that constrained where the contents could go.
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.
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.
