Cement and clinker control with AI — the kiln drives the whole plant, and every kcal counts.

The problem

Three planes of the kiln — and the lab arrives afterwards.

A cement plant runs four parallel flows that rarely meet in time:

1. Raw meal chemistry — the LSF, MS and MA moduli. They define optimal burning. Raw material varies from one quarry face to another and from one batch of corrective additives to the next.
2. Kiln burning — burning-zone temperature, fuel flow (fossil + alternative: RDF, biomass, tires), free lime in the clinker. It lives in the DCS and, in modern plants, in an APC (Picasso, OptimizeIT) that closes local loops.
3. Final cement quality — Blaine fineness, particle size distribution, 2- and 28-day strengths under EN 197. It lives in the LIMS, in one-off tests.
4. Energy use and emissions — kcal/kg clinker, kWh/t cement, alternative fuel substitution rate, CEMS data for the environmental audit.

The kiln supervisor knows it — the kiln drives everything. An LSF deviation at the inlet costs hours further downstream in lost strength or excess fuel. Out-of-range free lime (>2%) lowers 28-day strength and is discovered in the lab hours later. The classic system works — and when it fails, it costs tons of fuel and downgraded batches.

How it fits the IRIS system

iLEAN does not replace the APC or the DCS — it sits on top and cross-checks what the APC never looks at.

The problem with cement control is not a lack of measurements: it is measurements the APC watches inside its own loop, but that nobody cross-checks with the LIMS, the quarry and the fuel mix at the same time. iLEAN acts as the putty that seals those cracks — without replacing the APC, without touching the DCS, respecting OT isolation with the three rings.

Edge sees the clinker on the conveyor. Connect reads the DCS, APC, LIMS and CEMS wherever they are. The Agents cross-check against the quarry and the fuel mix. The person signs — never the other way round.

The three iLEAN pieces applied to cement and clinker control:

• Edge — a vision-equipped terminal (CNN) over the clinker conveyor. It reads color, apparent particle size and texture — capturing the veteran's eye that spots excess free lime or under-burning at a glance. It turns that into a continuous 24/7 signal. It works with no network.
• Connect — reads raw meal proportioning, the kiln curve and fuel flow from the DCS. Reads current setpoints from the APC. Reads strengths and Blaine fineness from the LIMS. Reads stack emissions from the CEMS. And it captures what comes from outside: analysis of the active quarry face, the supplier's RDF certificate, the hourly energy bill. At second zero.
• Agents — they live in ring 3. They cross-check raw meal chemistry against burning, against final quality and against energy use. They identify energy optimization windows the APC cannot see because it only watches its own loop. They keep the CEMS dossier and the fuel mix dossier up to date for the environmental audit.

See the full IRIS architecture →

Before and after

Control with APC + LIMS + spreadsheets vs. cross-checked control with iLEAN

Aspect	Control with DCS + APC + LIMS	With iLEAN Edge + Connect + Agents
Reading the clinker on the conveyor	The veteran's eye when they walk past	Edge with vision 24/7, continuous signal
Detecting out-of-range free lime	LIMS, hours later	Anticipated hours ahead by cross-checking raw meal + burning
Change of quarry face	Phone call to the kiln supervisor	In the system at second zero, linked to the batch
Fuel mix (RDF, biomass)	Spreadsheet kept by the calciner operator	Cross-checked against LSF and expected quality
Energy optimization	The APC watches its own loop	The Agent sees the whole plant and proposes windows
CEMS dossier for the audit	Assembled by hand at month-end	Kept automatically, ready for the auditor

Impact estimate

Impact estimate for your plant — to be validated with your numbers.

The block below is an estimate to be validated with the specific data of your plant. We put it forward so the committee has an order of magnitude; we refine it during the diagnostic.

• Cement plant with a dry-process kiln, cyclone preheater, calciner running alternative fuel substitution (RDF, biomass), CEM I and CEM II.
• Edge pilot over the clinker conveyor + Connect + an Agent cross-checking LSF/free lime/energy use. First value in a few weeks.
• Indicative payback between 4 and 9 months, depending on current energy use (kcal/kg clinker) and the percentage of downgraded batches in recent years.
• Expected fuel consumption reduction of ≥ 3-5% in the optimization windows detected by the agent (conservative estimate, to be validated).
• The hard lever: a kiln burning tens of tons per hour saves hundreds of thousands of euros a year for every percentage point of fuel. The pilot pays for itself in the first quarter.

And the kiln supervisor's reasonable doubt

“What if the AI proposes cutting fuel and my kiln goes out?” — the Agents do not execute in the DCS or in the APC. They propose optimization windows to the kiln supervisor, who decides. The APC keeps closing its loops exactly as it does today. Reliability in anchored tasks (cross-checking DCS, LIMS and quarry data) sits below 1.5%^[1]. The AI here does not invent a new setpoint — it proposes an adjustment based on the raw meal history, the fuel mix and final quality. The person sees the why and signs.

^[1] OpenAI paper “Why Language Models Hallucinate”, 2025 — on the reliability of AI in anchored tasks.

Related topics you may find useful: asphalt and bitumen control · prestressed concrete control · float glass control.