ASM1 beluchtingsmodel

This is the first EVOLV process node — a live software twin of the beluchting (aeration) step of a treatment plant.

What it models

In an aeration tank we blow air into the wastewater so that bacteria can eat the pollution. How fast they work depends on oxygen, food, temperature and more. The internationally standard way to describe that biology is the Activated Sludge Model No. 1 (ASM1) — published in 1987 by an IWA task group — a set of equations covering carbon oxidation, nitrification (ammonia → nitrate) and denitrification (Wikipedia: Activated sludge model). This node implements the plug-flow variant of ASM1 in JavaScript / Node-RED, so the aeration tank can run as a real-time software mirror of the real one.

Why it matters — grounded in a real case

At RWZI Bath, this model was used to test the PLC control software before rollout: engineers could watch how the new controls reacted against a software model of the aeration and catch its behaviour before it ever touched the live plant. That one exercise is estimated to have saved at least €50k — a one-off, but a concrete demonstration that a process twin pays for itself.

Savings on software like this are hard to put a recurring number on, so the business case here is illustrative rather than annual.