| Mill Power | kW | Electricity | €/kWh | ||
| Ancillaries | kW | R&M | €/t | ||
| Total | kW | Clinker | €/t | ||
| Clinker tonnes | €/t | ||||
| €/t | |||||
| CO₂ | €/t | ||||
| Currency, € = | Clinker CO₂ Factor | kg/t |
| Additive Cost/t | ||||
| Dosage g/t | ||||
| t/hr | ||||
| kWh/t | 0 | 0 | 0 | 0 |
| kWh/t cost | 0 | 0 | 0 | 0 |
| R&M Cost/t | 0 | 0 | 0 | 0 |
| Composition cost/t 1 | 0 | 0 | 0 | 0 |
| CO₂ cost/t 1 | 0 | 0 | 0 | 0 |
| Sum | 0 | 0 | 0 | 0 |
| Saving/t | 0 | 0 | 0 | 0 |
| Additive Cost/t | 0 | 0 | 0 | 0 |
| Net Saving/t | 0 | 0 | 0 | 0 |
| Annual Saving € | 0 | 0 | 0 | 0 |
| % Return | 0 | 0 | 0 | 0 |
| 1 Assumes 5% gypsum | ||||
The calculation quantifies the cost difference between a reference cement recipe and an optimized, lower‑clinker recipe, then deducts the additive cost to yield the net benefit per tonne.
Net Saving per tonne is defined as:
$$\Delta_{\text{net}} = (C_{\text{ref}} + E_{\text{ref}}) - (C_{\text{opt}} + E_{\text{opt}}) - C_{\text{add}}$$
Composition cost \(C\) includes raw‑material, CO₂ and maintenance expenses; Energy cost \(E\) is the mill’s kWh/tonne output times the electricity tariff; Additive cost \(C_{\text{add}}\) is dosage (g/t) × additive price, converted to €/t.
Annual Saving (€) is:
$$S_{\text{annual}} = \Delta_{\text{net}} \times V_{\text{annual}}$$
where \(V_{\text{annual}}\) is total annual cement production (t).
Drive power of the mill’s main motor, in kilowatts (kW). This is the primary grinding energy input.
Power consumption of all auxiliary equipment (e.g. separator fans, conveyors). Typically ~25% of main drive power.
Average cost of electricity in €/kWh (plant‑ and region‑specific tariff).
Repair & maintenance cost per tonne, driven by wear of grinding media. Typically 0.8–1.5€/t.
Variable production cost of clinker (€/t), excluding CO₂ cost. variable cost
Annual clinker output in tonnes. This drives both material and energy budgets.
Variable cost of limestone filler (€/t). See variable cost.
Variable cost of slag filler (€/t). See variable cost.
Price of CO₂ emissions in €/t. Plant‑ and region‑specific; depends on allowances and ETS regulation. Consult an environmental specialist.
Emissions per tonne of clinker (kg CO₂/t). According to the EU ETS, the average is ≈813 kg CO₂/t.
Price of the additive in €/t. Used with dosage to compute additive cost per tonne of cement.
Addition rate in grams per tonne of cement (g/t).
Throughput in tonnes per hour (t/hr), i.e. the mill’s output rate.