Ash Content (Mineral Filler)
Compute the ash content of a paper, ash = (ash mass after ignition / paper mass)·100%, corresponding to the mineral filler (fillers and mineral pigments such as calcium carbonate, kaolin and titanium dioxide) added to the sheet. Fillers improve opacity, brightness, smoothness and cost (replacing expensive fiber), but in excess reduce strength. Printing papers have 10–25% ash. Enter the ash mass and the paper mass.
Result
—
Ash content (mineral filler)
Did you know that much of a sheet of printing paper is not fibre at all, but mineral? The ash content = (mass of ash after ignition / mass of paper)·100% measures exactly that: a sample is burned at ~525–900 °C, the organic part (the fibres) leaves as gas and what remains behind is the ash — the mineral fillers added to the sheet. The main ones are calcium carbonate (GCC and PCC, dominant today), kaolin (clay) and titanium dioxide (TiO₂, expensive, used for its extreme opacity). Why add mineral to paper? Several reasons: fillers improve opacity (print on the reverse side no longer shows through) and brightness; they leave the surface smoother and more uniform for printing; and — crucially — they replace costly fibre with cheap mineral, cutting cost (fibre is the largest single cost in papermaking). Printing and writing grades typically run 10–25% ash, and some reach 30%. There is a ceiling, though: excess filler gets in the way of the bonds between fibres, reducing strength (tensile, tear) and it can cause dusting and sizing trouble. Finding the optimum filler level is a central technical and economic decision in papermaking. Kraft packaging grades, by contrast, carry almost no filler at all (strength comes first). Enter the ash mass and the paper mass.
Related Tools
BW Photo Paper Print Time
Estimates exposure seconds to print on B&W photo paper.
Clinker C3S Content (Bogue)
Estimates the tricalcium silicate content, the alite or C₃S, of a clinker using the Bogue equation, the mass balance that splits the four main oxides among the mineral phases: C₃S = 4.071 × CaO − 7.600 × SiO₂ − 6.718 × Al₂O₃ − 1.430 × Fe₂O₃, with contents as mass percentages. Alite is the phase that gives cement its early strength, and ordinary Portland clinker sits between 50% and 65% — below that the 3-day and 7-day strengths collapse, above that kiln fuel consumption rises and the heat of hydration becomes a problem in mass concrete. The negative coefficients are large, so the result is very sensitive to the chemical analysis: half a point more silica knocks 3.8 points off C₃S, and a composition outside the clinker range can even return a negative value, which simply means that mixture has not enough lime to form alite. The classic four-term Bogue equation was adopted, the one for clinker without gypsum; for finished cement the ASTM C150 version also subtracts 2.852 × SO₃ and discounts free lime from CaO. Enter the CaO, SiO₂, Al₂O₃ and Fe₂O₃ contents.
Battery Charge Time (mAh)
Estimate charge time t (h) = capacity (mAh) / charger current (mA).
Pulping Yield
Compute the yield of a pulping (wood cooking) process, Y = (dry pulp mass / dry wood mass)·100%, the fraction of wood converted into usable cellulose. Chemical (kraft) pulping has a low yield (~45–55%), since it dissolves lignin and part of the hemicelluloses; mechanical pulping reaches ~95%, but with lower-quality fibers. It is a central indicator of the process economics and type. Enter the dry pulp mass and the dry wood mass.
Tons per Centimeter Immersion (TPC)
Compute the tons per centimeter of immersion (TPC), TPC = Awp·ρ/100, from the waterplane area (Awp, in m²) and the water density (ρ ≈ 1.025 t/m³ at sea). It indicates how many tons of cargo must be loaded (or removed) for the ship to sink (or rise) by 1 cm. It is essential in the loading plan and draft control. Enter the waterplane area and the water density.
Linear Explosive Charge
Calculate the linear loading density of a blast hole, q = (π/4) × d² × ρ, from the hole diameter d (mm) and the explosive density ρ (g/cm³). The result, in kg of explosive per meter of hole, is how much explosive fits in each meter of charged column — a central parameter of rock blast design. Multiplied by the hole charge height, it gives the charge per hole; combined with the blasted rock volume, it gives the powder factor. Larger diameters and denser explosives raise the linear charge. Enter the hole diameter and the explosive density.
The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.