Raw Mix Design Calculator

Executive summary

Enter the oxide analyses of 3–5 raw materials (limestone, clay/shale, sand/silica, iron corrective, optional correction) and target moduli. The tool solves a deterministic least-squares mass balance for candidate proportions, then reports the blended chemistry, achieved LSF/SM/AM, deviations from target, and warnings when a target cannot be met within material bounds. It is advisory: the output is a candidate for review, not an instruction to change feeders, quarry, or setpoints.

Calculator

{
  "input": {
    "materials": [
      {
        "name": "Limestone",
        "oxides": {
          "CaO": 52,
          "SiO2": 3.5,
          "Al2O3": 1,
          "Fe2O3": 0.5,
          "LOI": 42
        }
      },
      {
        "name": "Clay/shale",
        "oxides": {
          "CaO": 1.5,
          "SiO2": 58,
          "Al2O3": 16,
          "Fe2O3": 7,
          "LOI": 8
        }
      },
      {
        "name": "Sand/silica",
        "oxides": {
          "CaO": 0.2,
          "SiO2": 95,
          "Al2O3": 1.5,
          "Fe2O3": 0.8,
          "LOI": 0.5
        }
      },
      {
        "name": "Iron corrective",
        "oxides": {
          "CaO": 1,
          "SiO2": 10,
          "Al2O3": 3,
          "Fe2O3": 80,
          "LOI": 2
        }
      }
    ],
    "targets": {
      "lsf": 96,
      "sm": 2.5,
      "am": 1.5
    }
  },
  "output": {
    "proportions": [
      {
        "name": "Limestone",
        "percent": 81.51
      },
      {
        "name": "Clay/shale",
        "percent": 15.43
      },
      {
        "name": "Sand/silica",
        "percent": 2.15
      },
      {
        "name": "Iron corrective",
        "percent": 0.91
      }
    ],
    "blendedOxides": {
      "CaO": 42.63,
      "SiO2": 13.93,
      "Al2O3": 3.34,
      "Fe2O3": 2.23,
      "MgO": 0,
      "SO3": 0,
      "LOI": 35.5
    },
    "moduli": {
      "lsf": 96,
      "sm": 2.5,
      "am": 1.5
    },
    "targets": {
      "lsf": 96,
      "sm": 2.5,
      "am": 1.5
    },
    "deviations": {
      "lsf": 0,
      "sm": 0,
      "am": 0
    },
    "feasible": true,
    "warnings": [],
    "assumptions": [
      "Oxide analyses are representative and on a consistent basis.",
      "LSF/SM/AM are computed from the four main oxides; MgO/SO3/LOI are carried for reporting only and do not enter the moduli.",
      "The solver minimizes squared deviation from the three modulus targets subject to mass balance and bounds; it does not optimize cost, burnability, or minor-constituent limits."
    ],
    "verificationNotes": [
      "Candidate blend for lab / QC / process-engineering / supervisor review only.",
      "Confirm against actual, current material analyses and a lab burnability / free-lime check before any use.",
      "This tool does not authorize feeder, quarry, setpoint, environmental, or spec decisions."
    ]
  }
}

Method

Blended oxides are linear in the material mass fractions. Each modulus target is rearranged into a linear equation in those fractions (LSF, SM, AM), plus a mass-balance equation (fractions sum to 1). The system is solved by ridge-regularized least squares; fixed percentages are substituted out and min/max bounds are enforced by deterministic redistribution. When bounds make a target unreachable, the closest in-bounds candidate is returned with a warning rather than fabricated precision.

Inputs needed

Outputs expected

Limitations & cautions

• Candidate proportions only — for lab/QC/process-engineering/supervisor review. Not an instruction to act.
• Hits LSF/SM/AM only; it does not optimize cost, burnability, alkali/sulfate/chloride limits, or minor-constituent targets.
• Garbage-in/garbage-out: results depend entirely on representative, current material analyses on a consistent basis.
• Moduli are computed from the four main oxides; MgO/SO3/LOI are carried for reporting only.
• Solver targets exact moduli; it does not model kiln burnability or free lime. A lab burnability/free-lime check is still required.
• Not a substitute for plant-specific QC review, lab trials, or applicable standards.

AI agent use cases

• Produce a candidate blend from material analyses and target moduli for a human to review.
• Show which targets are reachable with the given materials and bounds, and flag those that are not.
• Replicate the deterministic method from the stated formulas when the UI cannot be run.
• Hand the candidate to the raw-mix-correction prompt and the LSF/SM/AM and Bogue tools for cross-checking.

Human use cases

• First-pass proportioning for a process engineer to evaluate before any lab trial.
• Teaching aid showing how proportions move the moduli.

Related

Tools:lsf sm am calculator, bogue calculator

Prompts:raw mix correction

Pages:raw mix design, lsf sm am, clinker phases

Sources & assumptions

Assumption: Oxide analyses are representative and on a consistent basis.

Assumption: Moduli are ratio-invariant to a uniform LOI/ignition renormalization, so they are computed directly from the provided oxides.

General cement process-chemistry practice — proportioning and modulus relationships are standard