IBN-AD Anaerobic Digestion

Hydrodynamic Cavitation (HDC) is a mechanical pretreatment step within ALPS Ecoscience's offering. High-shear forces create microscopic bubbles that collapse violently, physically reducing particle size and separating lignin from cellulose and hemicellulose, particularly relevant for fibrous or lignocellulosic feedstocks, ahead of IBN-AD's own hydrolysis mechanism. The full SMASH package adds a dual-stage configuration on top of HDC, separating hydrolysis and methanogenesis into two optimised stages, delivered as a modular, plug-in-place unit with a managed support service from ALPS Ecoscience, with optional add-on modules for ammonia stripping and nutrient recovery. This gives three tiers depending on the feedstock: IBN-AD standalone, IBN-AD plus HDC for fibrous or lignocellulosic feedstocks, and the full SMASH package for maximum conversion efficiency.

Fibrous and lignocellulosic feedstocks, food waste with packaging residue or high-fibre agricultural residues, for instance, are difficult for digesters to break down efficiently and difficult to pump and mix. ALPS Ecoscience's HDC step mechanically reduces particle size and opens up fibre structures, while IBN-AD's own solubilization and hydrolysis increase the amount of organic material available for conversion. Combined, this reduces the viscosity of thick or fibrous feedstocks.

In IBN's own case study at a UK food waste digester, continuous IBN-AD dosing (250 ml per tonne of dry organic matter, added straight after the primary feed silo) was run for 88 days against a 60-day baseline. Methane yield per tonne of feedstock rose by 22% over the trial, from 143 m³ to 175 m³, adding roughly 86,500 m³ of methane in total despite the trial running through several unrelated operational disruptions, including feed pump issues and feedstock supply interruptions, which if anything worked against the result. The full case study, including the financial return calculated over the trial period, is available on request. Separately, in pilot testing of the full SMASH system by ALPS Ecoscience, pretreated feedstock was run against an untreated control across parallel digesters, at a controlled temperature and retention time, with continuous gas monitoring. Depending on the feedstock mix, the pretreated lanes produced up to 43% more methane per tonne of volatile solids and up to 30% more methane per tonne of COD than the untreated control, with an absolute methane content increase of over 5 percentage points. Gas production also arrived faster, peaking around day 3 in the best-performing mix versus day 12 for the untreated control. As above, case studies with the full data set are available on request.

The same pilot testing measured dewaterability after digestion. Pretreated digestate needed up to 10% less polymer to dewater, turbidity of the drainage water dropped by up to 62%, and free drainage volume increased. As above, the full supporting case studies are available on request.

Lignin-heavy and fibrous materials resist conventional digestion because their structure limits the surface area available to biology. ALPS Ecoscience's HDC step opens that structure mechanically, and IBN-AD's hydrolysis mechanism continues the breakdown from there, together increasing the share of a difficult feedstock that actually converts to biogas rather than passing through undigested.

IBN-AD achieves the same molecular outcome associated with enzymatic breakdown through a stable, non-living physico-chemical mechanism instead. No substrate-specificity limits, no cofactor requirements, no sensitivity to the pH swings or temperature extremes that affect biological enzymes. Where a fully biological pretreatment stage is preferred, the full SMASH package adds ALPS Ecoscience's own microbial inoculation stage on top of the mechanical and chemical pretreatment, as a distinct process running alongside IBN-AD, not something IBN-AD itself performs.

Because hydrolysis is often the rate-limiting step in digesting complex or fibrous material, speeding it up gives operators room to move on two fronts: processing the same feedstock in a shorter retention time (HRT), or increasing throughput at a higher organic loading rate (OLR) without pushing the digester out of balance. Several IBN-AD customers have reported exactly this kind of shift, faster gas release supporting a shorter HRT, and more consistent conversion supporting a higher OLR, though the specific figures vary by site and feedstock and are best discussed case by case. In practice this means an existing digester can either free up capacity for additional feedstock, or shorten its cycle time on the same feedstock, without new tank volume. As with any OLR increase, this still needs to stay within the digester's own stability limits (loading, mixing, alkalinity), IBN-AD helps make more of the available hydrolysis capacity usable, it doesn't remove those limits.