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SediLogic Technologies

The science

How bacterial enzymes break down organic sludge

Bacterial enzymes break organic material into smaller molecules that the organisms can use. Strain selection, product format, dose and temperature affect whether that happens where treatment is needed.

A technician pipetting samples into tube racks in an analytical microbiology laboratory.

01The mechanism

From organic solids to digestion

Light micrograph of stained Bacillus: dark blue rod-shaped bacterial cells and short chains against a pale background.

The organism · Bacillus, stained light micrograph. The rod-shaped cells and short chains are the spore-forming genus that secretes the proteases, lipases, amylases and cellulases the four links depend on — and that survives drying, which is why the two lead formats are dry.

01

Enzymes do the work

Published work shows that mixtures of protease, cellulase and lipase reduce total suspended solids by 30 to 50 per cent and improve settling. Protease plus cellulase outperforms either alone, and lipase augments the effect further.

02

Bacillus makes the enzymes

The genus Bacillus is the single most important bacterial source of exactly these enzymes, particularly proteases. That is why it is the backbone of essentially every serious product in this category.

03

Bacillus sporulates

Bacillus forms spores that tolerate drying, making it suitable for dry biological treatment products.

04

The format must sink

A liquid applied at the surface disperses into the water column. A sinking solid is engineered to fall through it and release at or within the sludge interface, which is where the target actually is.

02Organisms and format

Matching organisms to the treatment task

Different organisms perform different treatment tasks. The table shows why our dry sludge-treatment products do not address nitrogen permits.

Organism groupWhat it does to materialSurvives drying?Format implication
Bacillus spore-formers — subtilis, licheniformis, amyloliquefaciens, pumilus, megateriumBulk organic digestion. Proteases, lipases, amylases and cellulases acting on volatile solids.Yes, readilyFree choice of format. These carry the core sludge reduction work.
Nitrifiers — Nitrosomonas, NitrobacterAmmonia and nitrite oxidation. Directly relevant to nitrogen permit compliance.NoLiquid only. Roughly twelve-month shelf life, opaque packaging or refrigeration.
Pseudomonas and similar Gram-negative heterotrophsDegradation of more recalcitrant specific organics.PoorlyLiquid strongly preferred.
Photosynthetic and purple non-sulfur bacteriaMetabolic diversity in anaerobic zones; sulfide chemistry.NoLiquid only.

03The delivery problem

Getting bacteria to the sludge blanket

In a lagoon six to fifteen feet deep, surface-applied organisms need to reach the bottom sludge and remain there long enough to work. There is limited independent research on how effectively commercial products do this.

The peer-reviewed literature consistently identifies three dominant failure modes for freely suspended introduced cells: washout with effluent, predation by protozoa, and competitive exclusion by the resident community. Standard limnology adds that unmixed water bodies stratify, and that density gradients limit exchange between surface and bottom layers.

You cannot make a liquid sink. A tablet, puck or carrier particle is engineered to fall through the water column and release at or within the sludge interface. When the target is a blanket sitting under six to fifteen feet of water, that is a delivery advantage no reformulation of a liquid can match — which is why at least a dozen independent manufacturers have converged on sinking or carrier-based formats over two decades.

SURFACE-APPLIED LIQUIDDISPERSES IN THE COLUMNDENSE SINKING SOLIDREACHES THE INTERFACE6–15 FT
Peer-reviewedNot publishedIllustrative, not a result. The delivery advantage of a sinking format is why a dozen manufacturers converged on it — but even a solid reaches the sludge interface rather than distributing through the blanket, and no independent study measures what fraction of any surface-applied product reaches and persists at realistic depth. That gap is unsolved for every format, ours included.

04How to evaluate a supplier

Check the viable-count guarantee

Nearly every cell count published in this category is measured at manufacture. Almost nobody states a guaranteed count at the end of shelf life — which is the number that matters to the operator applying product eighteen months after it was fermented.

Ask for the viable count at manufacture and at the end of shelf life, and request the guarantee in writing.

While you are at it, treat cell count per gram as a weak proxy for performance. What reaches the sludge is concentration multiplied by dose, so a four billion CFU per gram block applied at thirty pounds delivers far more organisms than a ten billion CFU per gram tablet applied at five ounces. Neither figure tells you which species are present, which enzymes they produce, or whether they survive the descent. Use cell count to avoid buying something obviously weak, not to pick a winner.

Read the full evidence review

05Go deeper

Further reading and research

The articles below cover treatment mechanisms, organisms, delivery, operating conditions, field evidence and the claims boundary. Each includes its sources.

Prefer the primary sources? The scientific literature page is a cited bibliography of landmark research on bacteria in wastewater and on sludge reduction, from 1914 to now, each entry summarised.

Browse the bibliography