Decompose ΔR = R*_b − RCI(t) across operator-side levers. Each recommendation is bounded by historian-demonstrated operating points — guidance never exceeds what the plant has already achieved at this load.
| Lever | Handle (DCS) | Current | Target | Move | Attributed ΔR | Share |
|---|---|---|---|---|---|---|
CO breakthrough driver: CO | Burner tilt / secondary air staging | 65 ppm | 35.00 ppm | −30.00 ppm | 0.0253 | 41% |
Sootblowing cadence driver: Sootblowing | Wall-blower sequence interval | 240 min | 150.00 min | −90.00 min | 0.0152 | 24% |
Excess O₂ driver: O2 | FD fan bias / windbox damper | 3.6 % | 3.10 % | −0.50 % | 0.0127 | 20% |
FEGT driver: FEGT | Burner tilt / OFA bias | 1205 °C | 1170.00 °C | −35.00 °C | 0.0089 | 14% |
Attribution = (lever potential ÷ Σ potential) × ΔR. Lever potential = (current − target) × sensitivity, with target clamped to the historian-allowed range. Recommendations decay to zero as ΔR closes.
Lower excess air → higher flame T, higher ε_gas (more H₂O/CO₂ partial pressure), better radiative coupling. Bounded by CO breakthrough.
Persistent CO indicates incomplete combustion regime (soot-rich). Restoring clean-gas regime restores radiative attribution to gas species.
Elevated FEGT indicates radiative duty migrating downstream — water-wall coupling is degraded. Bounded by SH metal temps.
Longer cadence → fouling grows → ε_wall drops → ΔR widens. Bounded by erosion budget and steam-side stress.
ΔR(t) = R*_b − RCI(t)
→ attribute ΔR across { O2, CO, FEGT, sootblowing }
→ clamp each lever target to historian-allowed range
→ emit ranked guidance, decay to zero as ΔR closesEvery recommendation is bounded by points the plant has already demonstrated at the current load band. Guidance is advisory and auditable — not prescriptive control.