Calcium lignosulfonate is used with cement at three points: in the cement mill, in the raw-mix slurry of wet-process plants, and in the concrete or mortar made from the cement. This page covers each use, the grade data and how to test it.
Three Uses at a Glance
| Where | Function | What to measure |
|---|---|---|
| Concrete and mortar | Water reducer and set retarder | Slump, water content, setting time, strength |
| Cement mill | Grinding aid | Fineness (Blaine), residue, mill output, setting and strength of the cement |
| Wet-process raw mix | Slurry thinner (deflocculant) | Slurry viscosity at the target water content |
In Concrete and Mortar
This is the largest use. The GAC-CaLS-Construction TDS recommends 0.20–0.30% by weight of cement and gives up to 12% water-demand reduction. Dosage, standards and trial steps are on the water reducing agent guide; delaying set is on the set retarder guide.
As a Cement Grinding Aid
Grinding aids adsorb on fresh clinker surfaces and reduce the re-agglomeration of fine particles in the mill. The general liquid grade TDS lists use as a cement grinding aid. Because the additive stays in the cement, check the cement standard you produce to.
- Run the mill without additive and record output, Blaine fineness (ASTM C204 or EN 196-6) and residue.
- Add the lignosulfonate at two or three rates, keeping the clinker feed and separator settings fixed.
- Compare mill output and fineness at each rate.
- Test setting time (ASTM C191 or EN 196-3) and strength (ASTM C109 or EN 196-1) of the cement made.
As a Raw-Mix Slurry Thinner
In wet-process plants, a thinner lowers slurry viscosity so less water is needed to pump the raw mix, and less water has to be evaporated in the kiln. The general liquid grade TDS lists use as a raw-mix slurry deflocculant. Test it by measuring viscosity at a fixed water content across a dosage series.
Grades
| Parameter | Construction Grade (GAC-CaLS-Construction), TDS Rev. 2.0 |
|---|---|
| Form | Light brown powder |
| Bulk density | 0.8 g/cm³ |
| Moisture | 5% max |
| pH (5% solution) | 4–6 |
| Recommended dosage | 0.20–0.30% by weight of cement; higher dosages may retard set beyond specified limits |
| Water-demand reduction | Up to 12% |
| Packaging | 25 kg woven bags with PE liner; 500 kg or 600 kg jumbo bags |
| Shelf life | 12 months |
| Parameter | Liquid Calcium Lignosulfonate (GAC-CaLS-L), TDS Rev. 2.0 |
|---|---|
| Solid content | 45% min |
| Lignosulfonate content | 45% min (dry basis) |
| Reducing sugar | About 4% |
| Density | 1.265 g/ml |
| pH | About 5.0 |
| Packaging | Flexitank or IBC |
Typical values from the current TDS. Each lot ships with a COA.
Frequently Asked Questions
How is calcium lignosulfonate used with cement?
In three ways: as a water reducer in concrete and mortar made with the cement, as a grinding aid in the cement mill, and as a thinner for raw-mix slurry in wet-process kilns.
What dosage is used in concrete?
The GAC-CaLS-Construction TDS recommends 0.20–0.30% by weight of cement, with up to 12% water-demand reduction.
Is it a cement grinding aid?
Yes. The general liquid grade TDS lists use as a cement grinding aid. Dosage is set by mill trial, measuring fineness, mill output and cement properties.
Which standard covers grinding aids?
In the US, processing additions for cement are evaluated under ASTM C465. In Europe, additives in cement are covered by EN 197-1; check the current edition for limits.
Samples and Documents
Send the cement type, mix design, target slump or setting time, and the test standard you work to, to info@greenagrochem.com or use the contact form.
Related: calcium lignosulfonate in construction · admixture compatibility testing
